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Publisher: Elsevier   (Total: 3049 journals)

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Showing 1 - 200 of 3089 Journals sorted alphabetically
A Practical Logic of Cognitive Systems     Full-text available via subscription   (Followers: 7)
AASRI Procedia     Open Access   (Followers: 15)
Academic Pediatrics     Hybrid Journal   (Followers: 25, SJR: 1.402, h-index: 51)
Academic Radiology     Hybrid Journal   (Followers: 22, SJR: 1.008, h-index: 75)
Accident Analysis & Prevention     Partially Free   (Followers: 86, SJR: 1.109, h-index: 94)
Accounting Forum     Hybrid Journal   (Followers: 25, SJR: 0.612, h-index: 27)
Accounting, Organizations and Society     Hybrid Journal   (Followers: 30, SJR: 2.515, h-index: 90)
Achievements in the Life Sciences     Open Access   (Followers: 4)
Acta Anaesthesiologica Taiwanica     Open Access   (Followers: 5, SJR: 0.338, h-index: 19)
Acta Astronautica     Hybrid Journal   (Followers: 363, SJR: 0.726, h-index: 43)
Acta Automatica Sinica     Full-text available via subscription   (Followers: 3)
Acta Biomaterialia     Hybrid Journal   (Followers: 25, SJR: 2.02, h-index: 104)
Acta Colombiana de Cuidado Intensivo     Full-text available via subscription   (Followers: 1)
Acta de Investigación Psicológica     Open Access   (Followers: 2)
Acta Ecologica Sinica     Open Access   (Followers: 8, SJR: 0.172, h-index: 29)
Acta Haematologica Polonica     Free   (SJR: 0.123, h-index: 8)
Acta Histochemica     Hybrid Journal   (Followers: 3, SJR: 0.604, h-index: 38)
Acta Materialia     Hybrid Journal   (Followers: 229, SJR: 3.683, h-index: 202)
Acta Mathematica Scientia     Full-text available via subscription   (Followers: 5, SJR: 0.615, h-index: 21)
Acta Mechanica Solida Sinica     Full-text available via subscription   (Followers: 9, SJR: 0.442, h-index: 21)
Acta Oecologica     Hybrid Journal   (Followers: 10, SJR: 0.915, h-index: 53)
Acta Otorrinolaringologica (English Edition)     Full-text available via subscription   (Followers: 1)
Acta Otorrinolaringológica Española     Full-text available via subscription   (Followers: 3, SJR: 0.311, h-index: 16)
Acta Pharmaceutica Sinica B     Open Access   (Followers: 1)
Acta Poética     Open Access   (Followers: 4)
Acta Psychologica     Hybrid Journal   (Followers: 24, SJR: 1.365, h-index: 73)
Acta Sociológica     Open Access  
Acta Tropica     Hybrid Journal   (Followers: 6, SJR: 1.059, h-index: 77)
Acta Urológica Portuguesa     Open Access  
Actas Dermo-Sifiliograficas     Full-text available via subscription   (Followers: 4)
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Actualites Pharmaceutiques     Full-text available via subscription   (Followers: 5, SJR: 0.141, h-index: 3)
Actualites Pharmaceutiques Hospitalieres     Full-text available via subscription   (Followers: 4, SJR: 0.112, h-index: 2)
Acupuncture and Related Therapies     Hybrid Journal   (Followers: 4)
Acute Pain     Full-text available via subscription   (Followers: 13)
Ad Hoc Networks     Hybrid Journal   (Followers: 11, SJR: 0.967, h-index: 57)
Addictive Behaviors     Hybrid Journal   (Followers: 15, SJR: 1.514, h-index: 92)
Addictive Behaviors Reports     Open Access   (Followers: 6)
Additive Manufacturing     Hybrid Journal   (Followers: 7, SJR: 1.039, h-index: 5)
Additives for Polymers     Full-text available via subscription   (Followers: 21)
Advanced Cement Based Materials     Full-text available via subscription   (Followers: 3)
Advanced Drug Delivery Reviews     Hybrid Journal   (Followers: 132, SJR: 5.2, h-index: 222)
Advanced Engineering Informatics     Hybrid Journal   (Followers: 11, SJR: 1.265, h-index: 53)
Advanced Powder Technology     Hybrid Journal   (Followers: 17, SJR: 0.739, h-index: 33)
Advances in Accounting     Hybrid Journal   (Followers: 9, SJR: 0.299, h-index: 15)
Advances in Agronomy     Full-text available via subscription   (Followers: 15, SJR: 2.071, h-index: 82)
Advances in Anesthesia     Full-text available via subscription   (Followers: 26, SJR: 0.169, h-index: 4)
Advances in Antiviral Drug Design     Full-text available via subscription   (Followers: 3)
Advances in Applied Mathematics     Full-text available via subscription   (Followers: 6, SJR: 1.054, h-index: 35)
Advances in Applied Mechanics     Full-text available via subscription   (Followers: 11, SJR: 0.801, h-index: 26)
Advances in Applied Microbiology     Full-text available via subscription   (Followers: 22, SJR: 1.286, h-index: 49)
Advances In Atomic, Molecular, and Optical Physics     Full-text available via subscription   (Followers: 16, SJR: 3.31, h-index: 42)
Advances in Biological Regulation     Hybrid Journal   (Followers: 4, SJR: 2.277, h-index: 43)
Advances in Botanical Research     Full-text available via subscription   (Followers: 3, SJR: 0.619, h-index: 48)
Advances in Cancer Research     Full-text available via subscription   (Followers: 25, SJR: 2.215, h-index: 78)
Advances in Carbohydrate Chemistry and Biochemistry     Full-text available via subscription   (Followers: 9, SJR: 0.9, h-index: 30)
Advances in Catalysis     Full-text available via subscription   (Followers: 5, SJR: 2.139, h-index: 42)
Advances in Cell Aging and Gerontology     Full-text available via subscription   (Followers: 4)
Advances in Cellular and Molecular Biology of Membranes and Organelles     Full-text available via subscription   (Followers: 12)
Advances in Chemical Engineering     Full-text available via subscription   (Followers: 27, SJR: 0.183, h-index: 23)
Advances in Child Development and Behavior     Full-text available via subscription   (Followers: 10, SJR: 0.665, h-index: 29)
Advances in Chronic Kidney Disease     Full-text available via subscription   (Followers: 9, SJR: 1.268, h-index: 45)
Advances in Clinical Chemistry     Full-text available via subscription   (Followers: 29, SJR: 0.938, h-index: 33)
Advances in Colloid and Interface Science     Full-text available via subscription   (Followers: 18, SJR: 2.314, h-index: 130)
Advances in Computers     Full-text available via subscription   (Followers: 16, SJR: 0.223, h-index: 22)
Advances in Dermatology     Full-text available via subscription   (Followers: 12)
Advances in Developmental Biology     Full-text available via subscription   (Followers: 11)
Advances in Digestive Medicine     Open Access   (Followers: 7)
Advances in DNA Sequence-Specific Agents     Full-text available via subscription   (Followers: 5)
Advances in Drug Research     Full-text available via subscription   (Followers: 22)
Advances in Ecological Research     Full-text available via subscription   (Followers: 45, SJR: 3.25, h-index: 43)
Advances in Engineering Software     Hybrid Journal   (Followers: 26, SJR: 0.486, h-index: 10)
Advances in Experimental Biology     Full-text available via subscription   (Followers: 7)
Advances in Experimental Social Psychology     Full-text available via subscription   (Followers: 43, SJR: 5.465, h-index: 64)
Advances in Exploration Geophysics     Full-text available via subscription   (Followers: 3)
Advances in Fluorine Science     Full-text available via subscription   (Followers: 8)
Advances in Food and Nutrition Research     Full-text available via subscription   (Followers: 51, SJR: 0.674, h-index: 38)
Advances in Fuel Cells     Full-text available via subscription   (Followers: 16)
Advances in Genetics     Full-text available via subscription   (Followers: 15, SJR: 2.558, h-index: 54)
Advances in Genome Biology     Full-text available via subscription   (Followers: 11)
Advances in Geophysics     Full-text available via subscription   (Followers: 6, SJR: 2.325, h-index: 20)
Advances in Heat Transfer     Full-text available via subscription   (Followers: 22, SJR: 0.906, h-index: 24)
Advances in Heterocyclic Chemistry     Full-text available via subscription   (Followers: 9, SJR: 0.497, h-index: 31)
Advances in Human Factors/Ergonomics     Full-text available via subscription   (Followers: 26)
Advances in Imaging and Electron Physics     Full-text available via subscription   (Followers: 2, SJR: 0.396, h-index: 27)
Advances in Immunology     Full-text available via subscription   (Followers: 36, SJR: 4.152, h-index: 85)
Advances in Inorganic Chemistry     Full-text available via subscription   (Followers: 9, SJR: 1.132, h-index: 42)
Advances in Insect Physiology     Full-text available via subscription   (Followers: 3, SJR: 1.274, h-index: 27)
Advances in Integrative Medicine     Hybrid Journal   (Followers: 6)
Advances in Intl. Accounting     Full-text available via subscription   (Followers: 4)
Advances in Life Course Research     Hybrid Journal   (Followers: 8, SJR: 0.764, h-index: 15)
Advances in Lipobiology     Full-text available via subscription   (Followers: 2)
Advances in Magnetic and Optical Resonance     Full-text available via subscription   (Followers: 9)
Advances in Marine Biology     Full-text available via subscription   (Followers: 16, SJR: 1.645, h-index: 45)
Advances in Mathematics     Full-text available via subscription   (Followers: 10, SJR: 3.261, h-index: 65)
Advances in Medical Sciences     Hybrid Journal   (Followers: 6, SJR: 0.489, h-index: 25)
Advances in Medicinal Chemistry     Full-text available via subscription   (Followers: 5)
Advances in Microbial Physiology     Full-text available via subscription   (Followers: 4, SJR: 1.44, h-index: 51)
Advances in Molecular and Cell Biology     Full-text available via subscription   (Followers: 22)
Advances in Molecular and Cellular Endocrinology     Full-text available via subscription   (Followers: 10)
Advances in Molecular Toxicology     Full-text available via subscription   (Followers: 8, SJR: 0.324, h-index: 8)
Advances in Nanoporous Materials     Full-text available via subscription   (Followers: 4)
Advances in Oncobiology     Full-text available via subscription   (Followers: 3)
Advances in Organ Biology     Full-text available via subscription   (Followers: 2)
Advances in Organometallic Chemistry     Full-text available via subscription   (Followers: 15, SJR: 2.885, h-index: 45)
Advances in Parallel Computing     Full-text available via subscription   (Followers: 7, SJR: 0.148, h-index: 11)
Advances in Parasitology     Full-text available via subscription   (Followers: 7, SJR: 2.37, h-index: 73)
Advances in Pediatrics     Full-text available via subscription   (Followers: 24, SJR: 0.4, h-index: 28)
Advances in Pharmaceutical Sciences     Full-text available via subscription   (Followers: 13)
Advances in Pharmacology     Full-text available via subscription   (Followers: 15, SJR: 1.718, h-index: 58)
Advances in Physical Organic Chemistry     Full-text available via subscription   (Followers: 8, SJR: 0.384, h-index: 26)
Advances in Phytomedicine     Full-text available via subscription  
Advances in Planar Lipid Bilayers and Liposomes     Full-text available via subscription   (Followers: 3, SJR: 0.248, h-index: 11)
Advances in Plant Biochemistry and Molecular Biology     Full-text available via subscription   (Followers: 8)
Advances in Plant Pathology     Full-text available via subscription   (Followers: 5)
Advances in Porous Media     Full-text available via subscription   (Followers: 4)
Advances in Protein Chemistry     Full-text available via subscription   (Followers: 17)
Advances in Protein Chemistry and Structural Biology     Full-text available via subscription   (Followers: 20, SJR: 1.5, h-index: 62)
Advances in Psychology     Full-text available via subscription   (Followers: 62)
Advances in Quantum Chemistry     Full-text available via subscription   (Followers: 5, SJR: 0.478, h-index: 32)
Advances in Radiation Oncology     Open Access  
Advances in Small Animal Medicine and Surgery     Hybrid Journal   (Followers: 2, SJR: 0.1, h-index: 2)
Advances in Space Biology and Medicine     Full-text available via subscription   (Followers: 5)
Advances in Space Research     Full-text available via subscription   (Followers: 360, SJR: 0.606, h-index: 65)
Advances in Structural Biology     Full-text available via subscription   (Followers: 8)
Advances in Surgery     Full-text available via subscription   (Followers: 7, SJR: 0.823, h-index: 27)
Advances in the Study of Behavior     Full-text available via subscription   (Followers: 30, SJR: 1.321, h-index: 56)
Advances in Veterinary Medicine     Full-text available via subscription   (Followers: 16)
Advances in Veterinary Science and Comparative Medicine     Full-text available via subscription   (Followers: 13)
Advances in Virus Research     Full-text available via subscription   (Followers: 5, SJR: 1.878, h-index: 68)
Advances in Water Resources     Hybrid Journal   (Followers: 44, SJR: 2.408, h-index: 94)
Aeolian Research     Hybrid Journal   (Followers: 5, SJR: 0.973, h-index: 22)
Aerospace Science and Technology     Hybrid Journal   (Followers: 331, SJR: 0.816, h-index: 49)
AEU - Intl. J. of Electronics and Communications     Hybrid Journal   (Followers: 8, SJR: 0.318, h-index: 36)
African J. of Emergency Medicine     Open Access   (Followers: 5, SJR: 0.344, h-index: 6)
Ageing Research Reviews     Hybrid Journal   (Followers: 8, SJR: 3.289, h-index: 78)
Aggression and Violent Behavior     Hybrid Journal   (Followers: 417, SJR: 1.385, h-index: 72)
Agri Gene     Hybrid Journal  
Agricultural and Forest Meteorology     Hybrid Journal   (Followers: 16, SJR: 2.18, h-index: 116)
Agricultural Systems     Hybrid Journal   (Followers: 30, SJR: 1.275, h-index: 74)
Agricultural Water Management     Hybrid Journal   (Followers: 40, SJR: 1.546, h-index: 79)
Agriculture and Agricultural Science Procedia     Open Access  
Agriculture and Natural Resources     Open Access   (Followers: 2)
Agriculture, Ecosystems & Environment     Hybrid Journal   (Followers: 55, SJR: 1.879, h-index: 120)
Ain Shams Engineering J.     Open Access   (Followers: 5, SJR: 0.434, h-index: 14)
Air Medical J.     Hybrid Journal   (Followers: 5, SJR: 0.234, h-index: 18)
AKCE Intl. J. of Graphs and Combinatorics     Open Access   (SJR: 0.285, h-index: 3)
Alcohol     Hybrid Journal   (Followers: 11, SJR: 0.922, h-index: 66)
Alcoholism and Drug Addiction     Open Access   (Followers: 8)
Alergologia Polska : Polish J. of Allergology     Full-text available via subscription   (Followers: 1)
Alexandria Engineering J.     Open Access   (Followers: 1, SJR: 0.436, h-index: 12)
Alexandria J. of Medicine     Open Access   (Followers: 1)
Algal Research     Partially Free   (Followers: 8, SJR: 2.05, h-index: 20)
Alkaloids: Chemical and Biological Perspectives     Full-text available via subscription   (Followers: 3)
Allergologia et Immunopathologia     Full-text available via subscription   (Followers: 1, SJR: 0.46, h-index: 29)
Allergology Intl.     Open Access   (Followers: 4, SJR: 0.776, h-index: 35)
Alpha Omegan     Full-text available via subscription   (SJR: 0.121, h-index: 9)
ALTER - European J. of Disability Research / Revue Européenne de Recherche sur le Handicap     Full-text available via subscription   (Followers: 9, SJR: 0.158, h-index: 9)
Alzheimer's & Dementia     Hybrid Journal   (Followers: 46, SJR: 4.289, h-index: 64)
Alzheimer's & Dementia: Diagnosis, Assessment & Disease Monitoring     Open Access   (Followers: 4)
Alzheimer's & Dementia: Translational Research & Clinical Interventions     Open Access   (Followers: 4)
Ambulatory Pediatrics     Hybrid Journal   (Followers: 5)
American Heart J.     Hybrid Journal   (Followers: 49, SJR: 3.157, h-index: 153)
American J. of Cardiology     Hybrid Journal   (Followers: 48, SJR: 2.063, h-index: 186)
American J. of Emergency Medicine     Hybrid Journal   (Followers: 40, SJR: 0.574, h-index: 65)
American J. of Geriatric Pharmacotherapy     Full-text available via subscription   (Followers: 9, SJR: 1.091, h-index: 45)
American J. of Geriatric Psychiatry     Hybrid Journal   (Followers: 14, SJR: 1.653, h-index: 93)
American J. of Human Genetics     Hybrid Journal   (Followers: 32, SJR: 8.769, h-index: 256)
American J. of Infection Control     Hybrid Journal   (Followers: 26, SJR: 1.259, h-index: 81)
American J. of Kidney Diseases     Hybrid Journal   (Followers: 32, SJR: 2.313, h-index: 172)
American J. of Medicine     Hybrid Journal   (Followers: 46, SJR: 2.023, h-index: 189)
American J. of Medicine Supplements     Full-text available via subscription   (Followers: 3)
American J. of Obstetrics and Gynecology     Hybrid Journal   (Followers: 199, SJR: 2.255, h-index: 171)
American J. of Ophthalmology     Hybrid Journal   (Followers: 59, SJR: 2.803, h-index: 148)
American J. of Ophthalmology Case Reports     Open Access   (Followers: 6)
American J. of Orthodontics and Dentofacial Orthopedics     Full-text available via subscription   (Followers: 6, SJR: 1.249, h-index: 88)
American J. of Otolaryngology     Hybrid Journal   (Followers: 25, SJR: 0.59, h-index: 45)
American J. of Pathology     Hybrid Journal   (Followers: 27, SJR: 2.653, h-index: 228)
American J. of Preventive Medicine     Hybrid Journal   (Followers: 25, SJR: 2.764, h-index: 154)
American J. of Surgery     Hybrid Journal   (Followers: 35, SJR: 1.286, h-index: 125)
American J. of the Medical Sciences     Hybrid Journal   (Followers: 12, SJR: 0.653, h-index: 70)
Ampersand : An Intl. J. of General and Applied Linguistics     Open Access   (Followers: 6)
Anaerobe     Hybrid Journal   (Followers: 4, SJR: 1.066, h-index: 51)
Anaesthesia & Intensive Care Medicine     Full-text available via subscription   (Followers: 58, SJR: 0.124, h-index: 9)
Anaesthesia Critical Care & Pain Medicine     Full-text available via subscription   (Followers: 12)
Anales de Cirugia Vascular     Full-text available via subscription  
Anales de Pediatría     Full-text available via subscription   (Followers: 2, SJR: 0.209, h-index: 27)
Anales de Pediatría (English Edition)     Full-text available via subscription  
Anales de Pediatría Continuada     Full-text available via subscription   (SJR: 0.104, h-index: 3)
Analytic Methods in Accident Research     Hybrid Journal   (Followers: 4, SJR: 2.577, h-index: 7)
Analytica Chimica Acta     Hybrid Journal   (Followers: 37, SJR: 1.548, h-index: 152)
Analytical Biochemistry     Hybrid Journal   (Followers: 167, SJR: 0.725, h-index: 154)
Analytical Chemistry Research     Open Access   (Followers: 8, SJR: 0.18, h-index: 2)
Analytical Spectroscopy Library     Full-text available via subscription   (Followers: 12)
Anesthésie & Réanimation     Full-text available via subscription   (Followers: 1)
Anesthesiology Clinics     Full-text available via subscription   (Followers: 22, SJR: 0.421, h-index: 40)
Angiología     Full-text available via subscription   (SJR: 0.124, h-index: 9)
Angiologia e Cirurgia Vascular     Open Access  

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Journal Cover Agricultural Water Management
  [SJR: 1.546]   [H-I: 79]   [40 followers]  Follow
    
   Hybrid Journal Hybrid journal (It can contain Open Access articles)
   ISSN (Print) 0378-3774
   Published by Elsevier Homepage  [3049 journals]
  • Agro-industrial wastewater reuse for irrigation of a vegetable crop
           succession under Mediterranean conditions
    • Authors: Angela Libutti; Giuseppe Gatta; Anna Gagliardi; Pompilio Vergine; Alfieri Pollice; Luciano Beneduce; Grazia Disciglio; Emanuele Tarantino
      Pages: 1 - 14
      Abstract: Publication date: 31 January 2018
      Source:Agricultural Water Management, Volume 196
      Author(s): Angela Libutti, Giuseppe Gatta, Anna Gagliardi, Pompilio Vergine, Alfieri Pollice, Luciano Beneduce, Grazia Disciglio, Emanuele Tarantino
      In many countries of the Mediterranean region, characterized by frequent drought periods, agricultural production often occurs under water deficiency or conditions that cause the depletion of the existing water resources. In these areas, the reuse of reclaimed wastewater for crop irrigation could contribute to mitigate/decrease water shortage, support the agriculture sector and protect groundwater resources. In 1.5-year field experiments in Southern Italy (Apulia Region), the effects of irrigation with treated agro-industrial wastewater on soil properties, crops yield and qualitative traits of crop products, including their microbiological safety, were assessed. Groundwater (GW), secondary treated wastewater (SW) and tertiary treated wastewater (TW) from an innovative “on-demand” UV disinfection system were used to irrigate tomato and broccoli, cultivated in succession. The three irrigation water sources and the corresponding irrigated soils, plants and crop products were analyzed for the main physico-chemical characteristics, quali-quantitative parameters and fecal indicators. SW and TW showed higher values of the main physico-chemical parameters than GW. SW irrigated soil resulted in a significant increase of NH4-N, Na+, SAR, EC (below the threshold value beyond which a soil is defined as saline) during the first tomato crop cycle, and of pH during the broccoli growing season. Irrigation with treated wastewater did not significantly affect the marketable yield nor the qualitative traits of tomato and broccoli crops, except for the Na+ and NO3 − content (below the threshold levels defined by the European guidelines for vegetables). High levels of E. coli (above the Italian limit for reuse), Fecal coliforms and Fecal enterococci (up to 104 CFU 100ml−1) were observed in the SW and, when chlorination was not done, in the TW. Nevertheless, E. coli was not isolated from any sample of soil, plant and crop product, probably due to its rapid die-off. Moreover, low concentrations of Fecal coliforms and Total heterotrophic count were found in plant and crop product. The drip irrigation system used, which avoided the close contact between water and plant, may have contributed to this. Under the conditions applied in this study, the reuse of treated agro-industrial wastewater for irrigation can be considered an effective way to cope with agricultural water shortage in the Mediterranean area.
      Graphical abstract image

      PubDate: 2017-10-28T15:50:03Z
      DOI: 10.1016/j.agwat.2017.10.015
      Issue No: Vol. 196 (2017)
       
  • Measurement and simulation of water-use by canola and camelina under
           cool-season conditions in California
    • Authors: Nicholas George; Sally E. Thompson; Joy Hollingsworth; Steven Orloff; Stephen Kaffka
      Pages: 15 - 23
      Abstract: Publication date: 31 January 2018
      Source:Agricultural Water Management, Volume 196
      Author(s): Nicholas George, Sally E. Thompson, Joy Hollingsworth, Steven Orloff, Stephen Kaffka
      The agricultural sector of California is one of the most diverse and economically valuable in the world, but is dominated by woody perennial, and annual warm-season crops, dependent on irrigation. These face potential problems from restrictions to irrigation water supply and climate change. Canola and camelina could be used to diversify cool-season cropping in the state, but the water use of these species in the region is poorly understood. In this study, both the total and temporal water use of canola and camelina under cool-season production conditions in California were investigated using field-based and computer modeling approaches. Total and temporal water-use of both species were found to be similar to what has been observed in other regions under cool-season conditions. Observed seasonal water uptake patterns also closely matched predictions by the Agricultural Production Systems Simulator (APSIM) model. These results inform the utilization of these species as new crops in California and also contribute to estimates of water use by these globally significant oilseeds under Mediterranean to arid climate conditions.

      PubDate: 2017-10-28T15:50:03Z
      DOI: 10.1016/j.agwat.2017.09.015
      Issue No: Vol. 196 (2017)
       
  • An interval multi-objective programming model for irrigation water
           allocation under uncertainty
    • Authors: Mo Li; Qiang Fu; Vijay P. Singh; Dong Liu
      Pages: 24 - 36
      Abstract: Publication date: 31 January 2018
      Source:Agricultural Water Management, Volume 196
      Author(s): Mo Li, Qiang Fu, Vijay P. Singh, Dong Liu
      An interval linear multi-objective programming (ILMP) model for irrigation water allocation was developed, considering conflicting objectives and uncertainties. Based on the generation of interval numbers through statistical simulation, the ILMP model was solved using a fuzzy programming method. The model balances contradictions among economic net benefit, crop yield and water-saving in irrigation systems incorporating uncertainties in both objective functions and constraints that are based on the conjunctive use of surface water and groundwater. The model was applied to Hulan River irrigation district, northeast China. Tradeoffs between various crops in different subareas under different frequencies were analyzed, and scenarios with different objectives were considered to evaluate the changing trend of irrigation water allocation.Results indicated that the ILMP model provided effective linkages between revenue/output promotion and water saving, and offers insights into tradeoffs for irrigation water management under uncertainty.

      PubDate: 2017-10-28T15:50:03Z
      DOI: 10.1016/j.agwat.2017.10.016
      Issue No: Vol. 196 (2017)
       
  • Root system characterization and water requirements of ten perennial
           herbaceous species for biomass production managed with high nitrogen and
           water inputs
    • Authors: A. Barco; C. Maucieri; M. Borin
      Pages: 37 - 47
      Abstract: Publication date: 31 January 2018
      Source:Agricultural Water Management, Volume 196
      Author(s): A. Barco, C. Maucieri, M. Borin
      Although several studies have investigated the aboveground production of perennial herbaceous species for biomass production, only a few details are available on their root systems and water balance. This paper provides a root system characterization and a water balance calculation for ten perennial herbaceous species (Arctium lappa L., Arundo donax L., Carex acutiformis Ehrh., Carex riparia Curtis, Glyceria maxima (Hartm.) Holmb., Helianthus tuberosus L., Iris pseudacorus L., Lythrum salicaria L., Miscanthus x giganteus Greef et Deu., Symphitum x uplandicum Nyman) cultivated with high fertilizer and water inputs in a four-year study. Crop evapotranspiration (ETc) maintained the same seasonal trend for all studied species, with the highest cumulative seasonal average water losses for A. donax (1675.1mm) and the lowest for G. maxima (1406.0mm). During the growing season, crop coefficients followed a similar trend to that reported for ETc, with average seasonal values ranging from 1.9 for A. lappa and G. maxima to 2.6 for M. x giganteus. For all species soil moisture was higher in the deeper soil layers (20–50 and 50–90cm) than in the upper (0–20cm) where a high root system biomass was observed. At the end of the study, different root system biomass productions were found between species with the highest median value at 0–50cm depth for M. x giganteus (62.6Mgha−1) and the lowest for S. x uplandicum (0.5Mgha−1). Since these topics have not been well investigated in other studies, our initial results need to be confirmed in different climatic conditions.

      PubDate: 2017-11-11T10:15:33Z
      DOI: 10.1016/j.agwat.2017.10.017
      Issue No: Vol. 196 (2017)
       
  • Genotypic variation of physiological and morphological traits of seven
           olive cultivars under sustained and cyclic drought in Mendoza, Argentina
    • Authors: E.R. Trentacoste; O. Contreras-Zanessi; V. Beyá-Marshall; C.M. Puertas
      Pages: 48 - 56
      Abstract: Publication date: 31 January 2018
      Source:Agricultural Water Management, Volume 196
      Author(s): E.R. Trentacoste, O. Contreras-Zanessi, V. Beyá-Marshall, C.M. Puertas
      The effects of two deficit irrigation regimes on the physiological, morphological, vegetative, and reproductive traits of seven olive cultivars were studied in a pot experiment. Specific leaf area (SLA) and SPAD chlorophyll meter reading (SCMR) were measured over the experimental period. Their relationships with physiological traits and with each other were also tested. Three-year-old plants in pots were subjected to control regime (CI replaced daily water use), sustained deficit regime (SDI was applied daily at 35% of CI), and five successive drought cycles of 30days followed by rewatering (CDI). In all cultivars, SDI decreased stem water potential compared to CI. Under CDI, stem water potential reached the minimum, ∼–8MPa, but all cultivars recovered to potentials similar to the rewatering period. Stomatal conductance was significantly reduced in both deficit irrigation regimes compared to the control. Rewatering caused a slower recovery of stomatal conductance in ‘Selección Mendoza’, ‘Villalonga’ and ‘Arbequina’ than in the rest of cultivars. Across cultivars, specific leaf area decreased with water deficit, while SCMR increased. Specific leaf area was positively related with stem water potential (R2 =0.60), stomatal conductance (R2 =0.44) and trunk growth (R2 =0.31). In contrast, SCMR values were negatively related with stem water potential (R2 =0.59), stomatal conductance (R2 =0.52) and trunk growth (R2 =0.62). ‘Changlot’, ‘Arauco’ and ‘Nevadillo Blanco’ cultivars maintained lower SLA and higher SCMR under both deficit irrigation regimes and higher stomatal conductance recovery after rewatering. These cultivars also appear to be better adapted to drought prone environments.

      PubDate: 2017-11-11T10:15:33Z
      DOI: 10.1016/j.agwat.2017.10.018
      Issue No: Vol. 196 (2017)
       
  • Low and variable atmospheric coupling in irrigated Almond (Prunus dulcis)
           canopies indicates a limited influence of stomata on orchard
           evapotranspiration
    • Authors: Gerardo M. Spinelli; Richard L. Snyder; Blake L. Sanden; Matthew Gilbert; Ken A. Shackel
      Pages: 57 - 65
      Abstract: Publication date: 31 January 2018
      Source:Agricultural Water Management, Volume 196
      Author(s): Gerardo M. Spinelli, Richard L. Snyder, Blake L. Sanden, Matthew Gilbert, Ken A. Shackel
      The degree of coupling to the environment of almond (Prunus dulcis) orchards during periods of transient water stress was investigated in a two-year study in California. Plant water status was monitored weekly, before and/or after irrigation, measuring midday stem water potential (Ψstem) that ranged from −0.5 to −2MPa, while actual evapotranspiration (ETa) was measured with an eddy covariance tower. Irrigation was applied weekly following common commercial practice, resulting in weekly cycles of Ψstem. Despite Ψstem reaching levels shown to induce substantial stomatal closure, the ratio actual to reference evapotranspiration (ETa/ETo =Ka) did not show a decrease during weekly periods of low Ψstem in the two years of the study. Midday average canopy surface resistance (rcmid), computed by reversing the Penman-Monteith equation from eddy covariance ET data, yielded a statistically significant increase with a decrease in Ψstem, but just in the first year of the study. However, rcmid did not show a significant relationship with stomatal resistance measured at the leaf level with porometry and scaled-up to the canopy level. In the first year, rcmid showed a sharp increase after harvest, when Ka also decreased, perhaps produced by the composite effect of defoliation associated with harvest and stomatal closure associated with water stress. During the growing season, rcmid ranged from 0 to 100sm−1 and midday average aerodynamic resistance (ramid) ranged between 0 and 50sm−1. Despite rcmid being generally larger than ra, the midday average decoupling factor (Ω) averaged 0.7 during the irrigation season, indicating decoupled conditions. However, there was a large day to day fluctuation of midday Ω ranging from 0.16 to 0.98 mostly associated with rcmid and wind speed. This study indicated that tall and rough canopies can be relatively decoupled depending on the effect of wind speed and canopy resistance on the decoupling factor. From a water management point of view, this result suggests that inducing transient mild to moderate water stress may not produce substantial water savings in areas having low to moderate winds.

      PubDate: 2017-11-11T10:15:33Z
      DOI: 10.1016/j.agwat.2017.10.019
      Issue No: Vol. 196 (2017)
       
  • Viticultural irrigation demands under climate change scenarios in Portugal
    • Authors: H. Fraga; I. García de Cortázar Atauri; J.A Santos
      Pages: 66 - 74
      Abstract: Publication date: 31 January 2018
      Source:Agricultural Water Management, Volume 196
      Author(s): H. Fraga, I. García de Cortázar Atauri, J.A Santos
      Climate change projections for Southern Europe reveal warming and drying trends for the upcoming decades, bringing important challenges to Portuguese viticulture in particular. The present study analyses irrigation as an adaptation measure to ensure the future sustainability of viticultural yields in Portugal. The STICS crop model was used to simulate baseline (1981–2005) and future (2041–2070) grapevine yields in Portugal. Future yield decreases (yields are 60% with respect to baseline) over some of the innermost and most renowned winemaking regions of the country are found, following the decrease of precipitation in the growing season. As an adaptation measure, grapevine irrigation was tested for future climates. STICS irrigation replicates a highly efficient water use strategy, only applied when a certain water stress level is reached. The results indicate higher yields with this irrigation strategy, thus largely alleviating the projected yield decreases. Nonetheless, in some warmer and dryer regions, such as inner Alentejo and Douro/Porto, yield levels are still projected to decrease with irrigation (70–80% of baseline yields), though to a lesser extent when compared to non-irrigated simulations. This decrease is attributed to the synergistic effect of severe heat and water stresses in the future. Although these simulations aim at achieving the same yields and alcohol level in future scenarios as in baseline, applying irrigation may modify the wine typicity of each region and threaten the currently scarce water resources. Outlining appropriate, timely and cost-effective adaptation measures is critical for the sustainability of both the environment and the national Portuguese winemaking sector.

      PubDate: 2017-11-11T10:15:33Z
      DOI: 10.1016/j.agwat.2017.10.023
      Issue No: Vol. 196 (2017)
       
  • Informing regional water-energy-food nexus with system analysis and
           interactive visualization – A case study in the Great Ruaha River of
           Tanzania
    • Authors: Y.C. Ethan Yang; Sungwook Wi
      Pages: 75 - 86
      Abstract: Publication date: 31 January 2018
      Source:Agricultural Water Management, Volume 196
      Author(s): Y.C. Ethan Yang, Sungwook Wi
      In sub-Saharan Africa, water resources are scarce and subject to competing uses – especially for agricultural production, energy generation, and ecosystem services. These water intensive activities in the Usangu plains and the Ruaha National Park in southern Tanzania, present a typical case for such water competition at the water-energy-food nexus. To decipher the coupled human-nature interactions in the Great Ruaha River basin and effectively communicate the results to non-technical practitioners, the water-energy-food nexus competition in the system is simulated using an advanced water system modeling approach and findings are visualized via interactive web-based tools (Data-Driven Document, D3) that foster fuller understanding of the findings for both practitioners and stakeholders. Our results indicate that a combination of infrastructural and procedural measures, each acceptable from a social and economic perspective, and understanding that zero flows cannot be totally eliminated during dry years in the Ruaha National Park, are likely to be the best way forward. This study also reveals that the combination of improvements in irrigation efficiency, cutbacks on proposed expansion of irrigated lands, and a low head weir at the wetland outlet, significantly reduces the number of zero flow days (i.e., increasing ecosystem function), resulting in positive effects on agricultural sector from limited (if any) reduction in rice crop yields. These upstream measures are all relatively cost efficient and can combine to free-up resources for other economic activity downstream (i.e. more stable hydropower production).

      PubDate: 2017-11-11T10:15:33Z
      DOI: 10.1016/j.agwat.2017.10.022
      Issue No: Vol. 196 (2017)
       
  • Performance assessment of factory and field calibrations for
           electromagnetic sensors in a loam soil
    • Authors: J. Singh; T. Lo; D.R. Rudnick; T.J. Dorr; C.A. Burr; R. Werle; T.M. Shaver; F. Muñoz-Arriola
      Pages: 87 - 98
      Abstract: Publication date: 31 January 2018
      Source:Agricultural Water Management, Volume 196
      Author(s): J. Singh, T. Lo, D.R. Rudnick, T.J. Dorr, C.A. Burr, R. Werle, T.M. Shaver, F. Muñoz-Arriola
      Accurate continuous measurements of temperature (T), apparent electrical conductivity (ECa), apparent dielectric permittivity (εra), and volumetric water content (θv) are extremely valuable to irrigation management and other agronomic decisions. The performance of eight electromagnetic (EM) sensors (TDR315, CS655, HydraProbe2, 5TE, EC5, CS616, Field Connect, AquaCheck), were analyzed through a field study in a loam soil. T, ECa, and εra were compared in reference to overall average among all sensors, and θv in reference to a neutron moisture meter (NMM). The reported T and ECa difference among the sensors were within 1°C and 1dSm−1, respectively, at 0.15 and 0.76m depths. Among the single-sensor probes, the range of depth-combined (0.15 and 0.76m) RMSD for factory calibration varied from 0.039m3 m−3 (5TE) to 0.157m3 m−3 (CS616). In comparison to single-sensor probes, RMSD of Field Connect at combined depths (0.30 and 0.51m) was moderate (0.083m3 m−3), and RMSD of AquaCheck at combined depths (0.30 and 0.61m) was high (0.163m3 m−3). Regression calibrations improved θv accuracy substantially beyond factory calibrations, as RMSD of the evaluated sensors except Field Connect was below 0.025m3 m−3 using regression calibrations. The betterment in θv accuracy gained by using offset calibrations was smaller and less consistent than the improvements gained by using regression calibrations. The lower and upper bounds of the 95% confidence interval for mean RMSD of most sensors were below 0.02 and 0.04m3 m−3, respectively, when using depth-specific offset calibrations. The relative success of offset calibrations for certain sensors in this study is encouraging and may signal new opportunities. Because much of the uncertainty in sensor-reported θv for the sensors under evaluation was systematic, future work should aim to develop universal calibrations or facilitate site-specific calibrations.

      PubDate: 2017-11-11T10:15:33Z
      DOI: 10.1016/j.agwat.2017.10.020
      Issue No: Vol. 196 (2017)
       
  • An investigation of farm-scale adaptation options for cotton production in
           the face of future climate change and water allocation policies in
           southern Queensland, Australia
    • Authors: Allyson Williams; Shahbaz Mushtaq; Louis Kouadio; Brendan Power; Torben Marcussen; David McRae; Geoff Cockfield
      Pages: 124 - 132
      Abstract: Publication date: 31 January 2018
      Source:Agricultural Water Management, Volume 196
      Author(s): Allyson Williams, Shahbaz Mushtaq, Louis Kouadio, Brendan Power, Torben Marcussen, David McRae, Geoff Cockfield
      Modelling cotton production at the farm-scale provides insight into the importance of water management options in adapting to climate change, especially given the renewed focus of government policies on irrigation water access and allocations. Using an irrigated cotton farm in southern Queensland as a case study, we investigated two possible adaptation strategies in response to changes in water resources from projected climate change (CSIRO Mk3.5, A1FI scenario). The modelled farm produced irrigated cotton, wheat, maize, and non-irrigated sorghum. The adaptation Strategy 1 allowed the substitution of current (baseline) production system with a system of less intensive cotton (2m row spacing) and a maximum of 2 in-crop irrigations instead of 4. Whereas Strategy 2 allowed for the production option of dryland cotton in the rotation and implied as much 2m row spacing cotton planting as possible depending on the other cropping rules regardless of the state of water storages. These two strategies were examined using a bio-economic farm enterprise model by evaluating the effects of projected changes in yield, water use and farm profitability (gross margin, GM), which resulted from crops competing for resources (i.e. irrigation water). Results showed 14% less water available in the 2030s and 2050s compared to the baseline (1960–2010), as a result of climate change and water policy decisions, thereby reducing the input costs. Under Strategy 1 there were 12.1% and 4.4% yield decreases in 2030 and 2050, respectively; while under Strategy 2 the inter-annual yield variability and proportion of low yields (<5bales/ha) increased over the same periods. Without adaptation GMs were reduced by 27% and 43% in 2030 and 2050, respectively. Strategy 1 resulted in 8.8% increase and 15.8% decrease in 2030 and 2050, respectively. However with Strategy 2, GM increases were observed (49% and 12%, respectively in 2030 and 2050). Moreover, without appropriate adaptation options, the enterprise would have to reduce the area of irrigated cotton, causing reductions in farm business gross margins. Our findings suggested that decreased water availability would not significantly impact the cotton production system and profitability if suitable adaptation options are available.

      PubDate: 2017-11-11T10:15:33Z
      DOI: 10.1016/j.agwat.2017.10.026
      Issue No: Vol. 196 (2017)
       
  • Soil and irrigation heterogeneity effects on drainage amount and
           concentration in lysimeters: A numerical study
    • Authors: Iael Raij; Alon Ben-Gal; Naftali Lazarovitch
      Pages: 1 - 10
      Abstract: Publication date: 1 January 2018
      Source:Agricultural Water Management, Volume 195
      Author(s): Iael Raij, Alon Ben-Gal, Naftali Lazarovitch
      Water and solute fluxes measured from lysimeters located in the field can be used to estimate evapotranspiration, for irrigation scheduling and in solute leaching management. System-imposed heterogeneities are expected to affect the variability of the measured fluxes, and therefore the uncertainty of data obtained using lysimeters. In this study, local heterogeneities in soil hydraulic conductivity and dripper discharge rate were studied and their effect on drainage amount and concentration assessed. Three-dimensional simulations were performed with HYDRUS (2D/3D) with 100 simulations per treatment. The effect of three levels of soil and irrigation heterogeneities was studied for lysimeters of two different sizes (1m2 and 0.5m2). Additionally, three leaching fraction levels and water uptake reduction due to solute stress were evaluated. Coefficient of variations of the drainage amount and solute concentrations were evaluated for the different scenarios. Irrigation heterogeneity caused higher variability in drainage amount while soil heterogeneity caused higher variability in drainage concentration. The larger the lysimeter, or the higher the leaching fraction, the lower the variability for both drainage concentration and amount. Combined soil and irrigation heterogeneities produced no synergistic effect, suggesting that the variability measured in lysimeters was governed by the factor that caused the highest variability. When water uptake reduction due to salinity was considered, the same trends were observed. The results from this study can help to decide if to use either drainage concentration or amount values, for saline water irrigation management using lysimeters, according to the soil or irrigation heterogeneity levels.

      PubDate: 2017-10-08T15:27:58Z
      DOI: 10.1016/j.agwat.2017.09.012
      Issue No: Vol. 195 (2017)
       
  • Assessing potato transpiration, yield and water productivity under various
           water regimes and planting dates using the FAO dual Kc approach
    • Authors: Paula Paredes; Daniela D’Agostino; Mahdi Assif; Mladen Todorovic; Luis S. Pereira
      Pages: 11 - 24
      Abstract: Publication date: 1 January 2018
      Source:Agricultural Water Management, Volume 195
      Author(s): Paula Paredes, Daniela D’Agostino, Mahdi Assif, Mladen Todorovic, Luis S. Pereira
      Two years of experimental field data on potato (var. Spunta) were used to calibrate and validate the SIMDualKc model. This model adopts the FAO dual Kc approach that provides the partition of crop evapotranspiration into crop transpiration and soil evaporation. Results of model calibration show a good agreement between soil water observations and predictions, with low errors of estimate – RMSE <3.7% of the mean observed soil water – and high modelling efficiency (>0.87). The calibrated basal crop coefficients for the initial stage, mid-season and end of season are 0.15, 1.10 and 0.35, respectively. After model calibration, the crop transpiration simulations were used to derive the yield response factor (Ky =1.09). Coupling SIMDualKc with the Stewart’s model provided for a good prediction of yields, with NRMSE lower than 8%. Irrigation scheduling scenarios were simulated with SIMDualKc model for various planting dates and limited stress conditions. Related results have shown that anticipating planting dates to the second half of February could lead to less irrigation requirements, higher yields and better water productivity relative to consumptive water use (WPET), crop transpiration (WPT) and seasonal water use (WPWU). These WP indicators were useful comparators. Contrarily, the WP relative to season irrigation depths (WPIrrig) showed a great variation among scenarios and a tendency to be higher when deficit irrigation was applied, which contradicts the objectives of farmers in terms of obtaining high yields and economic returns. The model and methodologies used were adequate to support irrigation management advising for farmers.

      PubDate: 2017-11-11T10:15:33Z
      DOI: 10.1016/j.agwat.2017.09.011
      Issue No: Vol. 195 (2017)
       
  • How water amounts and management options drive Irrigation Water
           Productivity of rice. A multivariate analysis based on field experiment
           data
    • Authors: Federica Monaco; Guido Sali
      Pages: 47 - 57
      Abstract: Publication date: 1 January 2018
      Source:Agricultural Water Management, Volume 195
      Author(s): Federica Monaco, Guido Sali
      Rice cultivation is globally hampered by several conditions, which urge farmers to maintain adequate production levels while properly managing irrigation water. This has noticeable repercussions on the efficient use of the resource and on water productivity. Nonetheless, more often, this latter topic is addressed by estimating the respective values, without deeply investigating the possible causes behind such discrepancies. The main objective of this paper is to overcome such limitations, by (i) providing a comprehensive and updated overview of Irrigation Water Productivity (IWP) for rice, and (ii) exploring the role of irrigation water in determining IWP value. The analysis of experimental data collected from 51 studies reveals IWP to vary between 0.09 and 8.10kgm−3, with mean and median values of 1.36 and 0.85kgm−3 respectively; moreover, a non-linear relationship between irrigation water amounts and IWP (r2 =0.81) is depicted. Further on, data are analyzed using an econometric approach. Specifically, a multivariate linear regression model is used to shed light on the joint contribution of water inputs, regime and irrigation method to productivity. This demonstrates the significant roles of irrigation (β=−1.006) and rainfall (β=0.062) amounts, while aerobic regime and irrigation method is proved to be a further key driver (β=−0.305). Such results enable identifying the elements to be enforced, if increasing IWP for rice is the prime objective. Finally, some implications are derived for water policy and the connections with weather-climatic and environmental conditions that are globally affecting the availability of water in agriculture.

      PubDate: 2017-10-13T23:03:31Z
      DOI: 10.1016/j.agwat.2017.09.014
      Issue No: Vol. 195 (2017)
       
  • Predicting design water requirement of winter paddy under climate change
           condition using frequency analysis in Bangladesh
    • Authors: A.R.M.Towfiqul Islam; Shuang-He Shen; Shen-Bin Yang
      Pages: 58 - 70
      Abstract: Publication date: 1 January 2018
      Source:Agricultural Water Management, Volume 195
      Author(s): A.R.M.Towfiqul Islam, Shuang-He Shen, Shen-Bin Yang
      The effects of climate change on the agricultural sector are tremendous. Thus, it is essential to determine its impacts on agricultural water resources and to minimize adverse effects on crop production. The present study aims to simulate climate data based on SRES A1B scenario from the outputs of three General Circulation Models (GCMs) namely, FGOAL, HADCM3 and IPCM4 and examine the design water requirement (DWR) of winter paddy using frequency analysis under climate change condition in Bangladesh. The average change rates of DWR in four climatic zones were compared to baseline and the results were −12.16% (2020s), −0.28% (2055s), and 1.25% (2090s) for the FGOAL, −4.44% (2020s), 0.57% (2055s) and 1.25% (2090s) for the HADCM3, and −1.12% (2020s), 2.22% (2055s) and 6.69% (2090s) for the IPCM4. The change rates of gross paddy water demand (GPWD) for three GCMs ranged from −3.01% to 11.16%. In both cases of the DWR and GPWD, the change rates were above 3%, indicating a warning signal to the future winter paddy water management. The outcomes of this study can be used as basic data for the development of agricultural water resource management, which will help to minimize the drought-risk and to implement future agricultural water resource policies in Bangladesh.

      PubDate: 2017-10-13T23:03:31Z
      DOI: 10.1016/j.agwat.2017.10.003
      Issue No: Vol. 195 (2017)
       
  • Deficit irrigation provokes more pronounced responses of maize
           photosynthesis and water productivity to elevated CO2
    • Authors: Xiaojie Li; Shaozhong Kang; Xiaotao Zhang; Fusheng Li; Hongna Lu
      Pages: 71 - 83
      Abstract: Publication date: 1 January 2018
      Source:Agricultural Water Management, Volume 195
      Author(s): Xiaojie Li, Shaozhong Kang, Xiaotao Zhang, Fusheng Li, Hongna Lu
      It is very significant to study the impact of deficit irrigation on crop growth and water use under the future scenarios with elevated CO2 concentrations and reduced water availability. This study investigated the growth and yield differences of maize grown in a phytotron in response to elevated CO2 concentrations under different irrigation treatments. Two irrigation treatments were carried out: regular irrigation (RI) and deficit irrigation (DI), in which the irrigation amounts were respectively 100 and 70% of evapotranspiration (ET), with four CO2 concentrations (400, 550, 700, and 900μmolmol−1). Thus eight treatments, i.e. RI400, RI550, RI700, RI900, DI400, DI550, DI700, and DI900 were included in this study. Results show that, the relative reductions of stomatal conductance (gs ) and transpiration rate (Tr ) in response to elevated CO2 concentrations were higher under DI than RI, thus causing leaf temperature (Tleaf ) rose higher under DI due to the transpiration cooling effect. As photosynthetic rate (Pn ) and its physiological process were positively correlated with Tleaf , the relative increases of Pn and the resulting maximum leaf area index (LAImax ), total dry matter weight (TDW), and grain yield (GY) react to elevated CO2 concentrations were higher under DI than RI, as well as the leaf water use efficiency (WUEL ) and water productivity (WP). The DI900 treatment in which the irrigation amount was reduced by 30% only decreased the TDW and GY by 7 and 5% when compared with RI900. The variation of GY was consistent with the variation of kernels per ear (KPE), but was not directly related to hundred-grain weight (HGW). The above results show that when atmospheric CO2 concentrations rise in the future, deficit irrigation would be an effective way of saving water and would not only have a mitigating effect on water crises, but would also contribute to improving WP, which is more important in terms of actual production.

      PubDate: 2017-10-13T23:03:31Z
      DOI: 10.1016/j.agwat.2017.09.017
      Issue No: Vol. 195 (2017)
       
  • Water use of irrigated almond trees when subjected to water deficits
    • Authors: Manuel López-López; Mónica Espadador; Luca Testi; Ignacio Jesús Lorite; Francisco Orgaz; Elías Fereres
      Pages: 84 - 93
      Abstract: Publication date: 1 January 2018
      Source:Agricultural Water Management, Volume 195
      Author(s): Manuel López-López, Mónica Espadador, Luca Testi, Ignacio Jesús Lorite, Francisco Orgaz, Elías Fereres
      Recently planted intensive almond plantations may have access to limited water supply due to water scarcity thus, information on almond water use under limited irrigation is needed. Here, the soil water balance was used to assess the consumptive use (ET) of full irrigated, moderately stressed and severely stressed almond trees over a three-year study, as well as the relation between applied water and ET. Sap flow measurements in eight experimental trees were used to obtain independent transpiration (T) measurements. Evaporation from soil (ES) was modelled to estimate tree T from the water balance. Relative consumptive use in the deficit irrigation (DI) treatments largely exceeded the relative applied water, highlighting the need to measure ET in stressed treatments for hydrologic purposes. The moderately stressed treatments (irrigated at 65.5% of full irrigation) consumed 79.0% of maximum evapotranspiration (ET of 897mm), while the severely stressed treatment consumed 63.6% of ETc (ET of 722mm) when applied water was only 39.6% of control. On average, almond ETc approached 1200mm, Seasonal evolution of the transpiration coefficient yielded maximum peak values ranging from 0.99 to 1.08, and minimum peak values of 0.33 attained with a severe deficit irrigation strategy. Transpiration measured by Compensated Heat Pulse-Calibrated Average Gradient sap-flow (x), was compared to water balance T estimates (y), and yielded a very good relation over the three years of study (y=0.90x+4.23, r2 =0.81). The sap flow measurements proved to be useful to overcome the limitations of the soil water balance technique, revealing that almond trees were able to extract water from below the monitored depths and suggesting that deep percolation event must have occurred in spring and autumn.

      PubDate: 2017-10-13T23:03:31Z
      DOI: 10.1016/j.agwat.2017.10.001
      Issue No: Vol. 195 (2017)
       
  • Realistic evaluation of crop water productivity for sustainable farming of
           wheat in Kamin Region, Fars Province, Iran
    • Authors: Behrouz Abolpour
      Pages: 94 - 103
      Abstract: Publication date: 1 January 2018
      Source:Agricultural Water Management, Volume 195
      Author(s): Behrouz Abolpour
      Currently, the economic wheat production faces severe challenges due to an increasing number of droughts. In an effort to enhance yields, most arid and semi-arid areas increase the water volume used for irrigation and cultivation of wheat, resulting in an intensified pressure on water resource systems. Therefore, it has become increasingly important to determine the required water volume per unit area in relation to expected wheat performance. However, such an estimation of relevant performance factors has been difficult due to unpredictable water supply capacities and the lack of reliable estimates for the demand of water. The potential crop water productivity (PCWP) defined in this study was comparing with its actual value has which obtained from field measurements based on a new approach of risk quantification. Using this comparison of water use, the management coefficient was estimated, and the production reliability of wheat was calculated. Based on these factors, farms that had competently adapted their management in line with climate change and water availability were selected. The results reveal that only 26 of a total of 666 wheat farms which evaluated for this case study have had reliable crop water productivity and could thus be used as models for other farms. The results showed 100% increasing in CWP with a 27% reducing in hydro-module on these farms, in which case more than 34% will be reduced the groundwater withdrawal. Therefore, the sustainability of groundwater resources would be better, whereas the benefit cost ratio of the whole region and the superior farms has no significant difference. The amount of water that these farms use and the resulting yield can be a suitable reference to determine the expected yield and required water volume per unit area.

      PubDate: 2017-10-28T15:50:03Z
      DOI: 10.1016/j.agwat.2017.10.006
      Issue No: Vol. 195 (2017)
       
  • The role of superabsorbent hydrogel in bean crop cultivation under deficit
           irrigation conditions: A case-study in Southern Italy
    • Authors: A. Satriani; M. Catalano; E. Scalcione
      Pages: 114 - 119
      Abstract: Publication date: 1 January 2018
      Source:Agricultural Water Management, Volume 195
      Author(s): A. Satriani, M. Catalano, E. Scalcione
      This study was planned for investigating the role of biodegradable cellulose-based superabsorbent polymers in the management of water irrigation systems in bean crop cultivations in areas affected by water scarcity. The paper focused the attention on the bean crop (Phaseolus vulgaris L.) cultivated in the Mediterranean region during the summer seasons characterised by optimal thermal conditions, but with a systematic absence of water for irrigation due to the low level of precipitations. We analysed the performance and the role of cellulose-based superabsorbent in the irrigation systems where it is necessary to ensure a continuous and adequate level of soil moisture. Based on crop evapotranspiration demand calculated from the analysis of weather data, deficits and full-drip irrigation strategies were applied. Full and deficit irrigation treatments received 100, 70 and 50% of evapotranspiration demand, respectively. In addition, given amounts of superabsorbent polymer granules (SAPs) were mixed with the soil, in particular, 0, 5 and 10g were added to the soil for full and deficit irrigation treatments.This study highlights a significant difference between the treatments, the combination of deficit irrigation and soil amendment hydrogel leads to a maximization of the crop water productivity index. In fact, the highest water use efficiency indexes were obtained with soil amendment hydrogel strategies under water deficit irrigation conditions. Our findings could be useful to optimize the consume of water resources in bean crop cultivations in the Mediterranean regions.

      PubDate: 2017-10-28T15:50:03Z
      DOI: 10.1016/j.agwat.2017.10.008
      Issue No: Vol. 195 (2017)
       
  • Willingness to pay for irrigation water when groundwater is scarce
    • Authors: T. Knapp; K. Kovacs; Q. Huang; C. Henry; R. Nayga; J. Popp; B. Dixon
      Pages: 133 - 141
      Abstract: Publication date: 1 January 2018
      Source:Agricultural Water Management, Volume 195
      Author(s): T. Knapp, K. Kovacs, Q. Huang, C. Henry, R. Nayga, J. Popp, B. Dixon
      Conversion to surface water irrigation is one of the critical initiatives to address the decline in groundwater supply. A double-bounded dichotomous choice contingent valuation survey is used to estimate producers’ willingness to pay (WTP) for surface water supplied by irrigation districts in Arkansas, United States. The estimated mean WTP for irrigation water is 2.7¢/m3 ($33.21/acre-foot). Comparison indicates a significant share of producers are likely to have higher WTPs for surface water than the average pumping cost in the study area. Producers located in areas with less groundwater resources have higher WTPs. Producers that are more concerned with a water shortage occurring in the state in the next 10 years have higher WTPs. A somewhat unexpected result is that participation in the Conservation Reserve Program predicts lower WTPs. One possible explanation is that farmers see the transfer of land out of crop production as a more viable financial decision when groundwater supply decreases.

      PubDate: 2017-10-28T15:50:03Z
      DOI: 10.1016/j.agwat.2017.10.013
      Issue No: Vol. 195 (2017)
       
  • Irrigation with brackish water changes evapotranspiration, growth and ion
           uptake of halophytes
    • Authors: Omer Faruk Ozturk; Manoj K. Shukla; Blair Stringam; Geno A. Picchioni; Charlotte Gard
      Pages: 142 - 153
      Abstract: Publication date: 1 January 2018
      Source:Agricultural Water Management, Volume 195
      Author(s): Omer Faruk Ozturk, Manoj K. Shukla, Blair Stringam, Geno A. Picchioni, Charlotte Gard
      Water shortage due to low precipitation, less river flows and high evaporation, and salinity stress related to use of brackish groundwater for irrigation are prevalent in the arid and semi-arid southwestern United States. The brackish groundwater desalinated using a reverse osmosis (RO) system produces a highly concentrate waste and creates a disposal problem. The objectives of this greenhouse study in pots were to assess irrigation water salinity induced changes to the evapotranspiration (ET), volumetric leaching fractions (LF), soil salinity, and dry biomass yields of two halophyte species (Hordeum vulgare, and xTriticosecale). Plants were arranged in a completely randomized design and four irrigation treatments (EC=0.8, 5, 8 and 10dS/m) were applied for 90days during the two seasons. No significant differences were observed in the saturated hydraulic conductivity and soil water retention of sandy loam soil irrigated with different brackish waters. Total ET obtained from water balance was higher for plants irrigated with control than brackish waters only in season one. An increase in irrigation water salinity increased soil salinity and mean leaching fraction (LF) while mean ET decreased. There were no differences in dry biomass yield for both species in season 1, and very small differences in season 2. The sodium uptake primarily from irrigation water confirmed that both species were halophyte, can be grown with RO concentrate, and used as a salt substitute in animal fodder. However, in order to prevent soil salinization, RO irrigation should be done intermittently or until vegetation establishment in nonagricultural areas.

      PubDate: 2017-10-28T15:50:03Z
      DOI: 10.1016/j.agwat.2017.10.012
      Issue No: Vol. 195 (2017)
       
  • Modelling stover and grain yields, and subsurface artificial drainage from
           long-term corn rotations using APSIM
    • Authors: Jonathan J. Ojeda; Jeffrey J. Volenec; Sylvie M. Brouder; Octavio P. Caviglia; Mónica G. Agnusdei
      Pages: 154 - 171
      Abstract: Publication date: 1 January 2018
      Source:Agricultural Water Management, Volume 195
      Author(s): Jonathan J. Ojeda, Jeffrey J. Volenec, Sylvie M. Brouder, Octavio P. Caviglia, Mónica G. Agnusdei
      The Agricultural Production Systems Simulator (APSIM) is a key tool to identify agricultural management practices seeking to simultaneously optimize agronomic productivity and input use efficiencies. The aims of this study were to validate APSIM for prediction of stover and grain yield of corn in four contrasting soils with varied N fertilizer applications (156–269kgNha−1) and to predict timing and volume from artificial subsurface drains in continuous corn and corn-soybean rotations in a silty clay loam soil at West Lafayette, IN. The APSIM validation was carried-out using a long-term dataset of corn stover and grain yields from the North Central Region of IN. The CCC (Concordance Correlation Coefficient) and SB (Simulation Bias) were used to statistically evaluate the model performance. The CCC integrates precision through Pearson’s correlation coefficient and accuracy by bias, and SB indicates the bias of the simulation from the measurement. The model demonstrated very good (CCC=0.96; SB=0%) and satisfactory (CCC=0.85; SB=2%) ability to simulate stover and grain yield, respectively. Grain yield was better predicted in continuous corn (CCC=0.73–0.91; SB=19–21%) than in corn-soybean rotations (CCC=0.56–0.63; SB=17–18%), while stover yield was well predicted in both crop rotations (CCC=0.85–0.98; SB=1–17%). The model demonstrated acceptable ability to simulate annual subsurface drainage in both rotations (CCC=0.63–0.75; SB=2–37%) with accuracy being lower in the continuous corn system than in corn-soybean rotation system (CCC=0.61-0.63; SB=9–12%). Daily subsurface drainage events were well predicted by APSIM during late spring and summer when crop water use was high, but under-predicted during fall, winter and early spring when evapotranspiration was low. Occasional flow events occurring in summer when soils were not saturated were not predicted by APSIM and may represent preferential flow paths currently not represented in the model. APSIM is a promising tool for simulating yield and water losses for corn-based cropping systems in north central Indiana US.

      PubDate: 2017-10-28T15:50:03Z
      DOI: 10.1016/j.agwat.2017.10.010
      Issue No: Vol. 195 (2017)
       
  • Microbial-based soil quality indicators in irrigated and rainfed soil
           portions of Mediterranean olive and peach orchards under sustainable
           management
    • Authors: Silvia Pascazio; Carmine Crecchio; Marina Scagliola; Alba N. Mininni; Bartolomeo Dichio; Cristos Xiloyannis; Adriano Sofo
      Pages: 172 - 179
      Abstract: Publication date: 1 January 2018
      Source:Agricultural Water Management, Volume 195
      Author(s): Silvia Pascazio, Carmine Crecchio, Marina Scagliola, Alba N. Mininni, Bartolomeo Dichio, Cristos Xiloyannis, Adriano Sofo
      The main objective of this study was to apply microbial indicators of soil quality in drip-irrigated olive and peach orchards managed with sustainable agricultural practices. Soil characterization was carried out in different areas of the orchards along the row, under the drippers (Rdr), and along the inter-row, rainfed (IRrf), to evaluate the effects of irrigation. Two parameters were followed during one year: a) a biochemical soil indicator (Nc/Nk ratio) based on soil N/C turnover and soil enzyme activities, and b) the abundance of three important N-cycling genes (nifH, amoA and nosZ). Localized irrigation caused higher values of water content in the Rdr areas, compared to IRrf. The Nc/Nk ratio exhibited all the attributes of a reliable soil fertility indicator, being generally higher in irrigated Rdr areas. The abundance of nifH and amoA in the soil showed a trend similar to Nc/Nk, being affected by higher soil water content, while nosZ abundance was generally insensitive to irrigation. Both Nc/Nk and gene abundances, much more than the measured chemical, biochemical and molecular soil parameters considered alone, can give a precise idea on N and C soil dynamics, that in turn, affect soil quality and fertility.
      Graphical abstract image

      PubDate: 2017-10-28T15:50:03Z
      DOI: 10.1016/j.agwat.2017.10.014
      Issue No: Vol. 195 (2017)
       
  • Geothermal heat pumps for sustainable farm climatization and field
           irrigation
    • Authors: Luca Alberti; Matteo Antelmi; Adriana Angelotti; Giovanni Formentin
      Pages: 187 - 200
      Abstract: Publication date: 1 January 2018
      Source:Agricultural Water Management, Volume 195
      Author(s): Luca Alberti, Matteo Antelmi, Adriana Angelotti, Giovanni Formentin
      In intensive breeding farms, maintaining an adequate indoor thermal environment and air quality is crucial in order to establish healthy conditions and increase productivity. In the EU, fossil fuels and electricity are the main energy sources adopted for this purpose, yet introducing renewable energy sources and efficient Heating Ventilating Air Conditioning systems would reduce energy consumption and improve sustainability. Another environmental concern in agricultural production is related to the intensive use of fertilizers, causing nitrate contamination in surface water and groundwater. Therefore, innovative strategies to reduce fertilizers and simultaneously reduce primary energy consumption are worthy of investigation. This paper addresses both issues, studying the application of geothermal heat pumps in the agro-zootechnical sector, where they are rarely applied and thus their potential needs to be verified. The study considers systems based on the closed loop configuration, i.e. Ground Source Heat Pumps (GSHP), and on the open loop configuration, i.e. Groundwater Heat Pumps (GWHP). Firstly, a pilot GSHP system for a piglet stable in Northern Italy is presented. Thanks to the use of both ground source and thermal recovery of air ventilation, the system achieves an appreciable reduction in both primary energy consumption and running costs, compared with a more traditional system typically adopted in this kind of farm. Secondly, the feasibility of an innovative concept of a GWHP combined with the irrigation system is studied through numerical modelling. The area of the piglet stable is represented in a flow and heat transport model; groundwater used by the heat pump is re-injected up-gradient during the cold season, while it is used for irrigation during the warm season. The system would provide energy-efficient climatization to the farm stables and, at the same time, promote the reuse of nitrogen in cultivated fields as a result of groundwater recirculation through irrigation.
      Graphical abstract image

      PubDate: 2017-10-28T15:50:03Z
      DOI: 10.1016/j.agwat.2017.10.009
      Issue No: Vol. 195 (2017)
       
  • Modelling subsurface drainage and nitrogen losses from artificially
           drained cropland using coupled DRAINMOD and WHCNS models
    • Authors: Hao Liang; Zhiming Qi; Kelin Hu; Baoguo Li; Shiv O. Prasher
      Pages: 201 - 210
      Abstract: Publication date: 1 January 2018
      Source:Agricultural Water Management, Volume 195
      Author(s): Hao Liang, Zhiming Qi, Kelin Hu, Baoguo Li, Shiv O. Prasher
      For the simulation of soil water movement, nitrogen (N) dynamics, and crop growth under tile drainage, current interdisciplinary models or modules were integrated into an established model through a typical technique for solving specific soil-crop modeling issues. A DRAINMOD-based drainage component was developed for the soil Water Heat Carbon Nitrogen Simulator (WHCNS) model. The newly developed model was validated using two field experiment datasets from Iowa: (i) four year data of daily/monthly/annual subsurface drain flow and N losses, and seasonal crop growth data, and (ii) 16year data of subsurface drain flow. For the drainage-enhanced WHCNS model, the mean (n = 4; calibration/validation×corn/soybean) normalized root mean square errors (nRMSE) for soil water storage, crop dry matter, yield, and crop N uptake simulation were 8.0%, 18.9%, 6.9% and 12.5%, respectively. The nRMSE values for annual subsurface drainage and N losses totals were 5.8% and 37.9%, respectively. Meanwhile, the monthly subsurface drainage was 12.1%, and the N losses was 63.0%. For the 16-year drainage plots, the annual subsurface drainage simulated during the validation phase closely matched measured values in most years (coefficient of determination, R 2 =0.92; RMSE =59mm, nRMSE = 23.4%, index of agreement, IA =0.97, and Nash-Sutcliffe efficiency, NSE =0.9). Thus, indicating that the integrated model can be used to simulate water balance, N losses and crop growth in a subsurface drained crop production system. Based on scenario analyses, an optimal N application rate ranging from 100 to 120kgNha−1 was recommended to reduce subsurface drainage water nitrate concentrations within the federal drinking water standard (<10mgL−1) while maintaining corn yield. The newly developed model showed a great potential to evaluate the short-/long-term effects of subsurface drainage system operations on water balance, N losses and crop growth.

      PubDate: 2017-10-28T15:50:03Z
      DOI: 10.1016/j.agwat.2017.10.011
      Issue No: Vol. 195 (2017)
       
  • Prediction of wind drift and evaporation losses from sprinkler irrigation
           using neural network and multiple regression techniques
    • Authors: Hussein M. Al-Ghobari; Mohamed S. El-Marazky; Ahmed Z. Dewidar; Mohamed A. Mattar
      Pages: 211 - 221
      Abstract: Publication date: 1 January 2018
      Source:Agricultural Water Management, Volume 195
      Author(s): Hussein M. Al-Ghobari, Mohamed S. El-Marazky, Ahmed Z. Dewidar, Mohamed A. Mattar
      Wind drift and evaporation losses (WDEL) play a significant role in the development of water conservation strategies in sprinkler irrigation. In this study, artificial neural network (ANN) and multiple linear regression (MLR) models were developed by taking data collected from published studies on predicted WDEL for several design, operational, and meteorological conditions of variables in sprinkler irrigation. Five combinations of input variables, including riser height, operating pressure, main nozzle diameter, auxiliary nozzle diameter (da), water discharge by main nozzle, water discharge by auxiliary nozzles, wind speed (WS), air temperature, and relative humidity were used to create prediction models for WDEL. The ANN and MLR models were trained and tested on 70% and 30% of the data points, respectively. The accuracy of the models was assessed by the coefficients of correlation (r), overall indices of model performance (OI), root mean square errors (RMSE), and mean absolute errors (MAE). Statistical results showed that the ANN and MLR models with all input variables had the best predicting capabilities. When comparing the results of different ANN and MLR models, it was seen that the ANN models had more success in predicting WDEL. The ANN models gave higher r (0.843–0.956) and OI (0.794–0.909) values, and lower RMSE (2.662%–4.886%) and MAE (2.197%–3.729%) values compared to the MLR models in the training stage. The MLR models’ r values ranged from 0.794 to 0.864, OI values ranged from 0.747 to 0.816, RMSE values ranged from 4.562% to 5.514%, and MAE values ranged from 3.513% to 4.414%. Furthermore, a contribution analysis found that the design parameter da and the climatic parameter WS were considered to obtain the most robust estimation model. It can be stated that the ANN model is a more suitable tool than the MLR model for the prediction of WDEL from sprinkler-irrigation.

      PubDate: 2017-10-28T15:50:03Z
      DOI: 10.1016/j.agwat.2017.10.005
      Issue No: Vol. 195 (2017)
       
  • Response of sap flux and evapotranspiration to deficit irrigation of
           greenhouse pear-jujube trees in semi-arid northwest China
    • Authors: Yu Feng; Ningbo Cui; Taisheng Du; Daozhi Gong; Xiaotao Hu; Lu Zhao
      Pages: 1 - 12
      Abstract: Publication date: December 2017
      Source:Agricultural Water Management, Volume 194
      Author(s): Yu Feng, Ningbo Cui, Taisheng Du, Daozhi Gong, Xiaotao Hu, Lu Zhao
      The objective of this study was to investigate the response of sap flux (SF) and evapotranspiration (ET) to deficit irrigation (DI) at different growth stages of greenhouse pear-jujube trees (Zizyphus jujube Mill.). Taking full irrigation (FI) as the control treatment (CK), moderate water deficit (50% of FI) at bud burst to leafing stage (stage I) (T2), flowering to fruit set stage (stage II) (T3), fruit growth stage (stage III) (T4), and fruit maturation stage (stage IV) (T5) were treated on greenhouse 8-year old pear-jujube trees in two growing seasons. Water deficit at different growth stages reduced SF, after the re-watering, SF had significant compensatory effects. Therefore, compared with CK, water deficit treatments (T2–T5) didn’t decrease SF significantly for the whole growing seasons, with maximum decrease of 10.5%. Simultaneously, SF under T2–T5 showed typical diurnal patterns on sunny and cloudy days, and nighttime SF accounted for 23.7%–52.3% of total SF for all the weather conditions. There was significantly positive relationship between SF and reference evapotranspiration, with R2 of 0.349–0.594. Principal component analysis (PCA) indicated that 97% of SF of pear-jujube can be characterized by relative humidity (RH), solar radiation (Rs), air temperature (Ta), and vapor pressure deficit (VPD), and VPD was the main variable affecting SF for all the treatments (P<0.001). Averaging the two years, ET of pear-jujube were 258–288mm for all the treatments, compared with CK, T2–T5 could decrease ET by 2.3%–10.3%.

      PubDate: 2017-09-06T05:13:40Z
      DOI: 10.1016/j.agwat.2017.08.019
      Issue No: Vol. 194 (2017)
       
  • Field and numerical experiment of an improved subsurface drainage system
           in Huaibei plain
    • Authors: Yuan Tao; Shaoli Wang; Di Xu; Hongwei Yuan; Haorui Chen
      Pages: 24 - 32
      Abstract: Publication date: December 2017
      Source:Agricultural Water Management, Volume 194
      Author(s): Yuan Tao, Shaoli Wang, Di Xu, Hongwei Yuan, Haorui Chen
      New requirements are put forward for agricultural drainage system due to frequent floods and cultivated land shortage in Huaibei plain, China. The improved subsurface drainage is a more efficient drainage system by laying high permeability materials as filter above the drains based on conventional subsurface drainage whose function is limited by soil hydraulic conductivity. Field experiments was used to evaluate the performance of the improved subsurface drainage preliminarily and numerical experiments was used to explore the capacity of the improved subsurface drainage deeply. Based on calibration and validation by field experiment data, HYDRUS model was used to evaluate the impacts of design parameters of filter hydraulic conductivity, filter width and height, drain spacing and depth on improved subsurface drainage discharge with constant ponding depth. Then, water table depths at different distances from the pipe drain for improved and conventional subsurface drainage were simulated under initial conditions of saturated soil and no surface ponding. Besides, the daily water balance under improved subsurface drainage had been also studied. The result of field experiment showed that the discharge of improved subsurface drainage was about 1.9 times of the conventional subsurface drainage discharge under conditions of same surface ponding depths. The results of numerical experiments indicated that the improved subsurface drainage had a real-time drainage function for the reason that cumulative outflow increased by about 87% than conventional subsurface drainage within 12h after beginning draining. The improved subsurface drainage lowered water table to an appropriate depth faster than conventional ones, which could provide a more favourable soil moisture condition for crop growth. Furthermore, through daily water balance analysis of improved and conventional subsurface drainage with different rainfalls and initial water table depths, the results showed that subsurface drainage could reduce surface runoff effectively, especially for improved subsurface drainage. Good drainability of the improved subsurface drainage was beneficial to decrease the amount of soil water storage after rainfall and helpful to shorten subsequent draining time of water table drawdown. The research results could provide scientific basis for improved subsurface drainage design and lay a good foundation for its application. Meanwhile, it would be beneficial to enrich agricultural drainage technologies and promote development of agricultural drainage in China.

      PubDate: 2017-09-11T03:03:49Z
      DOI: 10.1016/j.agwat.2017.07.015
      Issue No: Vol. 194 (2017)
       
  • Identifying changes in irrigation return flow with gradually intensified
           water-saving technology using HYDRUS for regional water resources
           management
    • Authors: Qiuli Hu; Yonghui Yang; Shumin Han; Yanmin Yang; Zhipin Ai; Jiusheng Wang; Fengyun Ma
      Pages: 33 - 47
      Abstract: Publication date: December 2017
      Source:Agricultural Water Management, Volume 194
      Author(s): Qiuli Hu, Yonghui Yang, Shumin Han, Yanmin Yang, Zhipin Ai, Jiusheng Wang, Fengyun Ma
      Irrigation return flow is critical for both surface and groundwater resources in downstream catchments. However, studies sufficiently clarifying the dynamics of hydrological processes in relation to irrigation return flow are scarce. In this study, HYDRUS-2D/3D model was used to analyze four irrigation development scenarios in Aksu River Basin, a major tributary of Tarim River. The study determined the effect of agricultural water saving on the dynamics of irrigation return flow in the basin. The results showed that for the 1990s, the irrigation return flow coefficient for flood irrigation was 0.50. This suggested that 50% of the water used in irrigation returned as discharge in the lower reaches. With increasing water scarcity, irrigation amount dropped while drip irrigation with plastic mulch was intensified. Accordingly, the irrigation return flow coefficient dropped from 0.44 in the 2000s to 0.34 in the 2010s under flood irrigation and from 0.42 to 0.23 under drip irrigation. With the drastic drop, irrigation was no longer enough to stabilize soil salinity in the region. The recent irrigation plan requires further reduction in irrigation amount. Based on the projected effects of the new irrigation scheme on soil salt build-up, an optimized irrigation scheme showed that the irrigation return flow coefficient should remain at 0.25. And with the use of water-saving technology, irrigation return flow has dropped from 594.01mm in the 1990s to 164.62mm in the 2010s, which should be maintained at 186.37mm for the sustainability of the optimized irrigation scheme. The study also suggested that salinity was increasing in the downstream water systems due to irrigation return flow from land reclamation and water saving. This was a potential threat to the fragile riparian ecosystems in the study area.

      PubDate: 2017-09-11T03:03:49Z
      DOI: 10.1016/j.agwat.2017.08.023
      Issue No: Vol. 194 (2017)
       
  • Interactive effects of pH, EC and nitrogen on yields and nutrient
           absorption of rice (Oryza sativa L.)
    • Authors: Lihua Huang; Xuan Liu; Zhichun Wang; Zhengwei Liang; Mingming Wang; Miao Liu; Donald L. Suarez
      Pages: 48 - 57
      Abstract: Publication date: December 2017
      Source:Agricultural Water Management, Volume 194
      Author(s): Lihua Huang, Xuan Liu, Zhichun Wang, Zhengwei Liang, Mingming Wang, Miao Liu, Donald L. Suarez
      Soil salinity and sodicity can not only directly restrain crop growth by osmotic and specific ion stresses, it also may reduce grain yield indirectly by impacting plant absorption of essential nutrients. Ensuring adequate nitrogen is an important management aspect of rice production in saline-sodic soils. The objective of this study was to investigate the interaction of soil pH, salinity and nitrogen application on rice yield and nutrient absorption. We conducted a rice experiment in containers in a greenhouse. The soils were first leached with 9 target salt solutions of pH 7, 8 and 9 and electrical conductivity (EC) of 2, 6 and 10dSm−1. Nitrogen application rates were 100, 200 and 300kgNha−1. Rice grain yield and shoot weight significantly decreased with increasing soil pH and increasing soil EC, and significantly increased with increasing nitrogen application (P <0.001). However, at high EC and/or high pH yield was not significantly increased by increased N. High pH and high EC in soil significantly influenced the mineral nutrient content of rice shoots (P <0.05). High soil pH and soil EC stresses were superimposed on each other, the negative effects on rice were compounded. The results by stepwise regression analysis showed that soil pH very significantly and adversely impacts grain yield and was the major factor impacting rice grain yield (R2 =0.565, P <0.001). Nitrogen application provided a positive response under control and pH 7 at all salinity values, and at pH 8 under low salinity only. There was no significant response to additional N under pH 8 and elevated EC and no significant response at pH 9 for all EC values. Thus, adequate nitrogen application is an important technical measure for improving rice yield and promoting nutrient absorption in rice of high EC soils but not of high pH soils where pH is the major limiting factor for rice production in saline-sodic soils.

      PubDate: 2017-09-11T03:03:49Z
      DOI: 10.1016/j.agwat.2017.08.012
      Issue No: Vol. 194 (2017)
       
  • Identifying best crop management practices for chickpea (Cicer arietinum
           L.) in Northeastern Ethiopia under climate change condition
    • Authors: Adem Mohammed; Tamado Tana; Piara Singh; Adamu Molla; Ali Seid
      Pages: 68 - 77
      Abstract: Publication date: December 2017
      Source:Agricultural Water Management, Volume 194
      Author(s): Adem Mohammed, Tamado Tana, Piara Singh, Adamu Molla, Ali Seid
      Chickpea (Cicer arietinum L.) is one of the important cool season food legumes in the semi-arid northeastern Ethiopia; however, its productivity is adversely affected by a number of abiotic and biotic factors. The objectives of this study were to assess impacts of projected climate change on grain yield of chickpea by 2030s (2020–2049) and 2050s (2040–2069) and to identify crop management options that increase productivity of the crop. The CROPGRO-chickpea model in DSSAT (Decision Support System for Agrotechnology Transfer) was used to assess impacts of projected climate change on chickpea and to identify adaptation options. The crop model was first calibrated and evaluated in the study area for simulating growth, yield and water balance of the soil. The result of the model calibration and evaluation showed that there were close agreement between the simulated and observed values that showed the performance of the model to simulate growth, phenology and yield of chickpea under semi-arid northeastern Ethiopian condition. The calibrated model was used to assess impacts of projected climate changes on chickpea and identify crop management options. The impact of projected climate change was assessed for 2030s and 2050s time periods under all the RCPs with and without CO2 fertilization. To identify crop management options, different varieties of chickpea, supplemental irrigation and change in planting dates have been evaluated. The result of climate change impact analysis on chickpea showed that grain yield is predicted to significantly increase both by 2030s and 2050s under CO2 fertilization condition across all the RCPs as compared to baseline grain yield (1961–1990). However, simulation without CO2 showed that grain yield will not significantly increase by 2030s and 2050s across all the scenarios. Based on the prediction result it can be generalized that chickpea will be benefited from the projected climate changes in northeastern Ethiopia. According to the simulation result application of two supplemental irrigation (flower initiation and pod setting stages) and early sowing significantly (P <0.05) increase grain yield of chickpea in northeastern Ethiopia under the present and future climate conditions. Selection of appropriate cultivars based on the agroecology of the area has paramount important to increase chickpea productivity under the present and future climate condition.

      PubDate: 2017-09-11T03:03:49Z
      DOI: 10.1016/j.agwat.2017.08.022
      Issue No: Vol. 194 (2017)
       
  • Water saving practices enhance regional efficiency of water consumption
           and water productivity in an arid agricultural area with shallow
           groundwater
    • Authors: Jingyuan Xue; Huade Guan; Zailin Huo; Fengxin Wang; Guanhua Huang; Jan Boll
      Pages: 78 - 89
      Abstract: Publication date: December 2017
      Source:Agricultural Water Management, Volume 194
      Author(s): Jingyuan Xue, Huade Guan, Zailin Huo, Fengxin Wang, Guanhua Huang, Jan Boll
      Improving the efficiency of water consumption and water productivity is the key approach to satisfy sustainable water resource supply and food demand. As effective measures, water saving practices are implemented in arid and semi-arid regions. For areas with shallow groundwater, water used for irrigation is not entirely consumptively used. The majority of irrigation water infiltrations below the root zone are stored in shallow groundwater. This can be reused as groundwater based evapotranspiration (ETg) at the regional scale. Thus, actual regional efficiency of water consumption (REWC) based on all water within the hydrological system is greater than based on consumptive use only. Accurately evaluating the response of REWC and regional water productivity (RWP) to water saving practices is essential due to the complexity of the hydrological system. In this study, regional ETg and regional evapotranspiration (ET) of the past 20 years were reproduced in a typical arid irrigation district with shallow groundwater based on the water balance method. Furthermore, REWC and RWP were estimated to investigate the impact of water saving practices to regional water use. Simulation results show that groundwater is a significant water source of regional ET in arid regions with a shallow aquifer and contributes more than 16% of regional ET for the irrigation district. Water saving practice implementation enhances the contribution of groundwater to ET. After water saving practices implementation, annual REWC and RWP have been improved by 0.07 and 0.1kg/m3, respectively. Furthermore, negative correlation between REWC and I+P (the total water supply including rainfall and irrigation water diversion) and positive correlation between RWP and REWC demonstrate that water saving practices can reduce the non-beneficial water losses by evaporation and enhance productivity by a lower groundwater table. Overall, shallow groundwater plays an important role to enhance REWC and RWP and the contribution of groundwater to regional water use needs to be considered as part of a reasonable water saving strategy towards a sustainable agricultural system.

      PubDate: 2017-09-18T01:34:50Z
      DOI: 10.1016/j.agwat.2017.09.003
      Issue No: Vol. 194 (2017)
       
  • Essential irrigation and the economics of strawberries in a temperate
           climate
    • Authors: J. Morris; M.A. Else; D. El Chami; A. Daccache; D. Rey; J.W. Knox
      Pages: 90 - 99
      Abstract: Publication date: December 2017
      Source:Agricultural Water Management, Volume 194
      Author(s): J. Morris, M.A. Else, D. El Chami, A. Daccache, D. Rey, J.W. Knox
      Strawberries are a high value crop in the UK soft fruit sector, with the majority of production grown at field-scale and under protected (polytunnel) conditions. Despite its importance to the rural economy, there is surprisingly little published scientific evidence on the economics of irrigated strawberry production and the value of water in this horticultural sector. A survey of growers, supplemented by secondary data and industry sources, shows considerable variation in key physical and financial performance indicators, both within and between different strawberry production systems, as well as evidence of good practice. Water application depths ranged widely from 800 to over 2000m3 ha−1 according to grower and crop variety. Irrigation costs typically range between £1.30 and £2.50m−3 of water applied, highest where storage reservoirs and public water supplies are used. The average value of irrigation water for strawberry net of costs was about £6m−3, much higher than for field crops such as potatoes. The importance of a reliable water supply to support irrigated strawberry production is highlighted. Climate change and growing pressures on water resources are likely to force a greater interest in irrigation economics in the soft fruit sector, especially in the face of restrictions on summer abstraction and rising competition and charges for using public water supply.

      PubDate: 2017-09-18T01:34:50Z
      DOI: 10.1016/j.agwat.2017.09.004
      Issue No: Vol. 194 (2017)
       
  • Food and water security: Analysis of integrated modeling platforms
    • Authors: Kelsie McNeill; Kiera Macdonald; Ashutosh Singh; Andrew D. Binns
      Pages: 100 - 112
      Abstract: Publication date: December 2017
      Source:Agricultural Water Management, Volume 194
      Author(s): Kelsie McNeill, Kiera Macdonald, Ashutosh Singh, Andrew D. Binns
      Food and water security are directly linked through the agricultural sector and food production and processing. Increasing stresses on food and water resources, influenced by factors such as population growth and climate change, threaten global food and water security. Previous studies have attempted to address this issue with the development of various modeling frameworks, often combining food security and water security models to address the inter-relationship between the two concepts. This study first introduces some of the background and foundational principles behind food and water security models, then critically reviews models that jointly analyze the two concepts. Initially, the dynamic definitions and historic development of water and food security concepts are reviewed. Current global hydrological models and food production/consumption models are then discussed to provide requisite background on available modeling platforms that separately assess water and food security. This study then focuses on an evaluation of ten models that assess food and water security from an interdisciplinary perspective, providing in-depth analysis regarding input parameters, model processes, advantages and limitations. Results suggest that there is a need to further develop input datasets as well as spatial and temporal resolution in existing food and water security models. This will provide the foundation for the development of effective policies and strategies to mitigate future food and water security issues, while considering the protection of the natural environment.

      PubDate: 2017-09-23T03:45:31Z
      DOI: 10.1016/j.agwat.2017.09.001
      Issue No: Vol. 194 (2017)
       
  • Sticks and carrots to manage groundwater over-abstraction in La Mancha,
           Spain
    • Authors: Alvar Closas; François Molle; Nuria Hernández-Mora
      Pages: 113 - 124
      Abstract: Publication date: December 2017
      Source:Agricultural Water Management, Volume 194
      Author(s): Alvar Closas, François Molle, Nuria Hernández-Mora
      Over recent decades, groundwater-fed irrigation has sustained the social and economic development of La Mancha, Spain. Without much initial regulation and control, groundwater resources and aquifer levels decreased dramatically, threatening agriculture and also highly valuable groundwater-dependant wetland ecosystems. This paper presents as a historical analysis of the different policy tools used to manage and regulate groundwater abstraction in the Western Mancha Aquifer after Spain approved its 1985 Water Law. It analyses the panoply of control and management instruments laid out by the state to counter the resource depletion trend, demonstrating the necessity by regulatory bodies to complement soft incentives (carrots) with the threat of sanctions and groundwater access limitations (sticks). As this case study shows however, each policy modality has its legal and practical loopholes which can be negotiated and exploited by groundwater users to their own advantage. Improvements in groundwater levels starting in 2010 seem to be linked to aquifer recharge following an unprecedented wet cycle rather than the effectiveness of the policy tools.

      PubDate: 2017-09-18T01:34:50Z
      DOI: 10.1016/j.agwat.2017.08.024
      Issue No: Vol. 194 (2017)
       
  • A modified soil water deficit index (MSWDI) for agricultural drought
           monitoring: Case study of Songnen Plain, China
    • Authors: Huicai Yang; Huixiao Wang; Guobin Fu; Haiming Yan; Panpan Zhao; Meihong Ma
      Pages: 125 - 138
      Abstract: Publication date: December 2017
      Source:Agricultural Water Management, Volume 194
      Author(s): Huicai Yang, Huixiao Wang, Guobin Fu, Haiming Yan, Panpan Zhao, Meihong Ma
      Available soil water in the root zone is an essential component of the water balance process since it greatly affects the crop water uptake and crop growth. In this study, a modified soil water deficit index (MSWDI) was established on the basis of the concept of readily available water (RAW), with the accumulated effect considered. This modified index was applied in six agro-meteorological stations in Songnen Plain of China to monitor the agricultural drought. The results showed that: 1) The MSWDI showed similar spatial and temporal agricultural drought patterns as its inherent indices, such as the soil water deficit (SWD), soil moisture deficit index (SMDI) and atmospheric water deficit (AWD), but exhibited a delay between atmospheric and soil water processes; 2) The MSWDI has a better correlation with the crop yield than its inherent indices. For example, its overall correlation coefficient is about 0.6 with the crop yields among six study stations and −0.7 for the number of droughts, while their corresponding values are 0.5 and −0.6, 0.5 and −0.6, and 0.3 and −0.4 for SMDI, SWD and AWD, respectively; 3) The MSWDI could also identify a slightly higher number of reported drought events during the 2000–2012 in comparison with SMDI, SWD and AWD, although it also over-predicts the number of drought events same as other indices. It mainly comes from the uncertainty of reported drought events. The proposed index can be used for agricultural drought monitoring and provides a useful tool for agricultural meteorology and water resource management.

      PubDate: 2017-09-18T01:34:50Z
      DOI: 10.1016/j.agwat.2017.07.022
      Issue No: Vol. 194 (2017)
       
  • Effects of microbial community variation on bio-clogging in drip
           irrigation emitters using reclaimed water
    • Authors: Bo Zhou; Tianzhi Wang; Yunkai Li; Vincent Bralts
      Pages: 139 - 149
      Abstract: Publication date: December 2017
      Source:Agricultural Water Management, Volume 194
      Author(s): Bo Zhou, Tianzhi Wang, Yunkai Li, Vincent Bralts
      Drip irrigation emitter clogging is one of the key barriers to the development and application of reclaimed water drip irrigation technology. Reclaimed water typically contains large amounts of bacteria, and their excretions, the sticky extracellular polymeric substances (EPS). Indeed, different amounts and types of microorganisms affect drip irrigation emitter clogging, especially bio-clogging process, via excretive EPS. Therefore, it is important to study the dynamic microbial community structure and its effect on the emitter bio-clogging process. In this paper, a drip irrigation experiment using reclaimed water was carried out. Phospholipid fatty acids (PLFAs) in biofilm (bio-clogging substance) were taken as the biomarker of microbial community inside emitters, and the dynamic variation of microbial community in drip irrigation emitter and its effect on the clogging process were studied. The results showed that the microbial growth of biofilms inside 9 types of drip irrigation emitters could enhance emitter clogging, and the PLFAs showed S-shaped pattern with emitter clogging degrees (R2 >0.95, p< 0.01), which was closely associated with the variation of microbial community. There were 3–7 types of PLFAs commonly in biofilms within drip irrigation emitters, among which gram positive bacteria (i15:0, 16:0 and 18:0) were dominant in amounts, with the close contents of 24.4%–34.2%, 24.8%–37.2% and 24.2%–39.0%, respectively, and their total proportion exceeding 76.3%. The Pseudomonas (16:0) was found to be the most critical bacteria to affect emitter clogging as it performed better to decompose and utilize organic matters, and showed the best relation with clogging degrees, along with significant relations with other types of bacteria. Therefore, controlling gram positive bacteria, especially Pseudomonas was the most effective way to relieve emitter clogging. Their variation also changed the microbial community structure, and the diversity index (H), evenness index (J) and dominance index (D) of microbial community in biofilms varied within 1.08–1.53, 0.75–1.11 and 0.65–0.75. The diversity index and dominance index both decreased as the amounts and types of microorganisms increased. The total amount of the gram positive bacteria increased after their decrement, and resulted in the similar variation of the microbial community evenness index. The results of this study will establish a theoretical basis for exploring the effects of microbial community variation on emitter bio-clogging, and provide insight into the emitter clogging mechanisms and possible mitigation strategies.

      PubDate: 2017-09-23T03:45:31Z
      DOI: 10.1016/j.agwat.2017.09.006
      Issue No: Vol. 194 (2017)
       
  • Socio-economic factors influencing utilisation of rain water harvesting
           and saving technologies in Tharaka South, Eastern Kenya
    • Authors: F.W. Muriu-Ng’ang’a; M. Mucheru-Muna; F. Waswa; F.S Mairura
      Pages: 150 - 159
      Abstract: Publication date: December 2017
      Source:Agricultural Water Management, Volume 194
      Author(s): F.W. Muriu-Ng’ang’a, M. Mucheru-Muna, F. Waswa, F.S Mairura
      Low levels of soil moisture makes rain water harvesting and saving technologies important interventions for water supply and food production in arid and semi-arids lands of Kenya. Despite much research around this theme, factors affecting utilisation of these technologies by farmers have not been well understood and the low adoption and adaptation levels of these beneficial technologies remains a challenge. This paper extends this dimension with emphasis on Tharaka South sub-county where water scarcity, unreliable rainfall and soil water stress is a major cause of household food insecurity. Farm and social data were collected using a cross-sectional survey design targeting a total of 351 household heads. Data was analysed using descriptive statistics and logistic regression. The utilization of in situ rainwater harvesting and saving technologies was higher for trashlines (73%) as compared to micro-catchments, Zai pits (26%) and Negarims (13%). Socio-economic characteristics that were positively and significantly associated with Zai pit utilisation included household size (p<0.01), training in Zai pits (p<0.002), while total farm size (p<0.01) and land tenure (p<0.01) showed negative co-efficients. Both formal and informal sources of training were important tools in disseminating rain-water harvesting and saving technologies. The study concluded that farmer age, household size, farm size, farming history, training, and formal education were important factors which influenced utilisation of rain water harvesting and saving technologies in Tharaka sub-county. Specific approaches are needed to scale-up resource-intensive technologies (Fanya juu, Zai pits, and Negarims) compared to less resource-intensive technologies.

      PubDate: 2017-09-23T03:45:31Z
      DOI: 10.1016/j.agwat.2017.09.005
      Issue No: Vol. 194 (2017)
       
  • Evaluation of the best management practices in a semi-arid region with
           high agricultural activity
    • Authors: Zeynep Özcan; Elçin Kentel; Emre Alp
      Pages: 160 - 171
      Abstract: Publication date: December 2017
      Source:Agricultural Water Management, Volume 194
      Author(s): Zeynep Özcan, Elçin Kentel, Emre Alp
      The arid and semi-arid regions with water scarcity are vulnerable to several stressors such as urbanization, high water demand created by agricultural and industrial activities, point and non-point pollution sources, and climate change. Hence, proactive policies and sustainable water management strategies that are based on decision support systems are crucial in arid and semi-arid regions. Because of large expenses and implementation difficulties associated with the diffuse pollution abatement plans, many authorities are hesitant to initiate, especially those that may present a financial burden on population. Lake Mogan, a shallow lake, is located in a semi-arid region dominated by dry agricultural activities and has been in eutrophic state for the past 20 years. There has been several management alternatives suggested to improve the water quality in Lake Mogan and one of the alternative is the application of BMPs that include fertilizer management, conservation/no tillage, contouring, and terracing to reduce the amount of diffuse source pollutants. In this study, Soil and Water Assessment Tool (SWAT) Model is applied to evaluate the effectiveness of agricultural best management practices (BMPs) in the Lake Mogan watershed located in a semi-arid region. The most effective BMP scenario was found as the one in which three individual BMP scenarios (30% fertilizer reduction, no tillage, and terracing) were combined. With this scenario average annual load reductions of 9.3%, 8.6%, 8.0%, and 11.1% were achieved in sediment, nitrate, total nitrogen, and total phosphorus, respectively. Even with the most effective BMP strategy, high levels of nutrient reduction will not be achieved since non-irrigated agriculture and intermittent low-flow streams accounts majority of the study area. The outcomes suggest integrated solutions should be developed to improve water quality in Lake Mogan. It is aimed that this study will aid decision makers to implement effective best management practices in watersheds showing similar characteristics (i.e. topographical, hydrologic processes, LULC (Land use land cover) characteristics, agricultural activities, meteorological etc.) with the study area.

      PubDate: 2017-09-23T03:45:31Z
      DOI: 10.1016/j.agwat.2017.09.007
      Issue No: Vol. 194 (2017)
       
  • Inside Front Cover - Editorial Board Page
    • Abstract: Publication date: 1 January 2018
      Source:Agricultural Water Management, Volume 195


      PubDate: 2017-11-11T10:15:33Z
       
  • Inside Front Cover - Editorial Board Page
    • Abstract: Publication date: December 2017
      Source:Agricultural Water Management, Volume 194


      PubDate: 2017-10-13T23:03:31Z
       
  • Spatio-temporal salinity dynamics and yield response of rice in
           water-seeded rice fields
    • Authors: Mathias Marcos; Hussain Sharifi Stephen Grattan Bruce Linquist
      Abstract: Publication date: 1 January 2018
      Source:Agricultural Water Management, Volume 195
      Author(s): Mathias Marcos, Hussain Sharifi, Stephen R. Grattan, Bruce A. Linquist
      The scarcity of high quality irrigation water is a global issue facing rice growers, forcing many to adopt water management systems that may result in increased salinity and yield reductions. While salt concentrations in field water have been shown to vary depending on water management, the distribution and build-up patterns of dissolved salts are unclear. This study was conducted to elucidate the within field spatial and temporal salinity dynamics in water-seeded rice cropping systems, and to assess current salinity thresholds for rice yield reduction. In this two-year study, water and soil salinity concentrations of eleven field sites were monitored weekly, with three sampling points being established in the top, middle and bottom basins of each field. There was a consistent spatio-temporal water salinity pattern among all fields: the maximum water salinity within a field occurred during week 2 to week 7 after planting, and was greatest farther from the irrigation inlet and where soil salinity was high. A model developed to predict water salinity within a field indicates that, averaged over an entire growing season, the position within a field contributed to 82% of the variation explained by the model, while preseason soil salinity contributed to 18%. Importantly, field water salinity was determined to be the most sensitive salinity metric for rice yield, as preseason soil salinity was a poor predictor of yield loss. The threshold field water salinity concentration was estimated at 0.88dSm−1, lower than the previous report of 1.9dSm−1. These results illustrate the ability to predict water salinity in a rice field with few parameters, while highlighting the importance of field water salinity as the main salinity metric for rice cropping systems.

      PubDate: 2017-10-08T15:27:58Z
       
 
 
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