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- Effects of different fertilization practices on anammox activity,
abundance, and community compositions in a paddy soil-
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Abstract: Abstract The return of crop residue and green manure into agricultural soil is known to be important agricultural management strategies, yet how they affect the anammox process remains poorly characterized. A field experiment containing four treatments: chemical fertilizer (F), F plus rice straw (FS), FS plus green manure (FSM), FSM with integrated management (FSMM), was performed to examine the effects of incorporation of rice straw and green manure residues on anammox. The results showed that the anammox activities in FS and FSM treatments (0.65 and 0.80 nmol N g−1 soil h−1, respectively) were significantly lower than those in F and FSMM treatments (1.60 and 1.28 nmol N g−1 soil h−1, respectively). Anammox contributed 4.07%–4.95% of total N loss in soil incorporated with residues, lower than soil treated with chemical fertilizer only (9.13%), the remaining being due to denitrification. However, the abundance of the hzsB gene (the hydrazine synthase β-subunit gene) in FS and FSM treatments (1.13 × 106 and 1.18 × 106 copies g−1 soil) were significantly higher than soil using chemical fertilizer only (7.49 × 105 copies g−1 soil) while showed no significant difference with FSMM treatment (8.81 × 105 copies g−1 soil). Illumina sequencing indicated that Brocadia was the dominant anammox genus, following by Scalindua and Kuenenia. Anammox bacterial diversity was altered after 4-year incorporation of rice straw and green manure, as shown by α-diversity indices. We concluded that rice straw and green manure incorporated with mineral fertilizer reduce N removal from paddy soil in terms of anammox in spite of stimulating anammox bacterial growth. 
PubDate: 2022-09-01
- Immediate and long-term effects of invasive plant species on soil
characteristics-
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Abstract: Abstract Invasive plant species may alter soil characteristics or interact with the soil microbial community resulting in a competitive advantage. Our objectives were to determine: i) if invasive plant species alter soil properties; and ii) the long-term effects of invasive plant species on soil properties and subsequent implications on ecological restoration efforts. We focused on Lespedeza cuneata, a plant that may be allelopathic. Soil samples were collected from four locations in Central Missouri, USA: an old-field with abundant L. cuneata, two reconstructed sites, and a remnant prairie that has never been plowed. Soil health indictors were used to characterize soil properties at these sites. Nearly every soil property differed significantly between the unplowed prairie reference site and the other three sites. The reconstructed sites, however, generally did not differ from the invaded old-field. These results indicate that the reconstructed prairies are not fully recovered. Although above-ground traits, such as the plant community structure, appear similar to the prairie, the soil microbial community structure still resembles that of an invaded old-field site. These results indicate that more time may be needed before soil microbial populations fully recover after invasive plant removal. 
PubDate: 2022-09-01
- Assessment of microbial α-diversity in one meter squared topsoil
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Abstract: Abstract Due to the tremendous diversity of microbial organisms in topsoil, the estimation of saturated richness in a belowground ecosystem is still challenging. Here, we intensively surveyed the 16S rRNA gene in four 1 m2 sampling quadrats in a typical grassland, with 141 biological or technical replicates generating over 11 million sequences per quadrat. Through these massive data sets and using both non-asymptotic extrapolation and non-parametric asymptotic approaches, results revealed that roughly 15 919±193, 27 193±1076 and 56 985±2347 prokaryotic species inhabited in 1 m2 topsoil, classifying by DADA2, UPARSE (97% cutoff) and Deblur, respectively, and suggested a huge difference among these clustering tools. Nearly 500 000 sequences were required to catch 50% species in 1 m2, while any estimator based on 500 000 sequences would still lose about a third of total richness. Insufficient sequencing depth will greatly underestimate both observed and estimated richness. At least ∼911 000, ∼3461 000, and ∼1 878 000 sequences were needed for DADA2, UPARSE, and Deblur, respectively, to catch 80% species in 1 m2 topsoil, and the numbers of sequences would be nearly twice to three times on this basis to cover 90% richness. In contrast, α-diversity indexes characterized by higher order of Hill numbers, including Shannon entropy and inverse Simpson index, reached saturation with fewer than 100 000 sequences, suggesting sequencing depth could be varied greatly when focusing on exploring different α-diversity characteristics of a microbial community. Our findings were fundamental for microbial studies that provided benchmarks for the extending surveys in large scales of terrestrial ecosystems. 
PubDate: 2022-09-01
- Compatible package-based agriculture systems: an urgent need for
agro-ecological balance and climate change adaptation-
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Abstract: Abstract Besides contributing majorly in the growth of a country, agriculture is one of the severely affected sectors at present. Several modifications and adaptations are being made in agricultural practices to cope-up with the declining soil fertility and changing climate scenarios across the world. However, the development and adoption of a single agricultural practice may not help in the holistic mitigation of the impacts of climate change and may result in economic vulnerability to farmers. Therefore, it is high time to develop and recommend a group of agricultural practices i.e., package-based agriculture system having some compatibility for one another in the long term. In this article, a viewpoint has been given on some emergent agronomic practices adopted in the tropical agro-ecosystems which have potential to be developed as compatible agricultural package in combination. Moreover, we also emphasized on exploring some key indicators/environmental factors to assess the compatibility of different agronomic practices. For identifying the research transition from single to combined agricultural practices, a bibliometric analysis was performed by using conservation agriculture (CA), the system of rice intensification (SRI), organic agriculture and soil (biochar) amendment as the major agronomic practices being used for improving agro-ecological services such as improving nutrient cycling, soil fertility and crop productivity as well as climate change mitigation. The results revealed that scientific communities are now paying attention to exploring the role of combined agricultural practices for agro-ecological balance and climate change adaptation. Moreover, the limitations of the adoption of agronomic packages under different agro-climatic zones have also been highlighted. The recommendations of the study would further help the environmental decision-makers to develop potential measures for climate change mitigation without compromising the agro-ecological balance. 
PubDate: 2022-09-01
- Effect and mechanism of changes in physical structure and chemical
composition of new biochar on Cu(II) adsorption in an aqueous solution-
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Abstract: Abstract To improve the adsorption effect of biochar on heavy metal Cu(II), we prepared new biochar and explored its modification process influence on original biochar’s physical structure and chemical composition as well as its adsorption mechanism for Cu(II) in an aqueous solution. Through research work, we have reached some significant conclusions: (1) The modified biochar (M2–800) can adsorb Cu(II) at the rate of 98.039 mg g−1, 38.8 times higher than that of the original biochar C800 (2.525 mg g−1); (2) The biochar modification process boosts its etching and pore expansion, helping Cu(II) enter the inner surface of the adsorbent, but chemical adsorption is still the most essential fixation method for Cu(II); (3) The alkaline modification process promotes the formation of oxygen-containing functional groups, in which −OH/−COOH and iron ions would form C-O-Fe structures such as hydroxyl bridges (Fe-O−) and carboxy bridges (Fe-OOC−); (4) Carboxyl is the primary site of Cu(II) fixation in M2–800, and M2–800 has higher electronegativity (−47.8 mV) and larger pH (11.61), so that Cu(II) can be removed by electrostatic attraction and precipitation. 
PubDate: 2022-09-01
- Use of ciliate communities for monitoring ecological restoration of grain
for the green in north-western China-
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Abstract: Abstract A 1-year baseline survey was conducted in north-western China to evaluate the ecological restoration quality of grain for green (GFG) using soil ciliate communities. The aims of this study were focused on analyzing the changes of soil ciliate communities in four plots (A, GFG for 15 years; B, GFG for 13 years; C, layland; D, cultivated land) for GFG environmental assessment. Simultaneously we studied the effects of vegetation communities and physical-chemical variables with GFG changes on soil ciliates. A total of 114 species of ciliates were identified among the four sample sites, representing 9 classes, 14 orders, 22 families and 37 genera. The community patterns of the soil ciliates were significantly correlated with the individual abundance of aboveground plants, soil water content, and soil porosity. The contents of total nitrogen were the main factor affecting the soil ciliate community composition. The species number, individual abundance, and diversity index of the ciliates were each in the order A>B>C>D; that is, the community composition of ciliates was complicated with the implementation of the GFG. It was shown that the succession of ciliate community shifts toward promoting the complexity with the progress of GFG. These findings demonstrate that soil ciliate communities may be used as a useful indicator to evaluate the effects of the ecological restoration quality of GFG. 
PubDate: 2022-09-01
- Zooming in to acquire micro-reaction: Application of microfluidics on soil
microbiome-
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Abstract: Abstract Microfluidics confers unique advantages in microbiological studies as these devices can accurately replicate the micro- and even nano-scale structures of soil to simulate the habitats of bacteria. It not only helps us understand the spatial distribution of bacterial communities (such as biofilms), but also provides mechanistic insights into microbial behaviors including chemotaxis and horizontal gene transfer (HGT). Microfluidics provides a feasible means for real-time, in situ studies and enables in-depth exploration of the mechanisms of interactions in the soil microbiome. This review aims to introduce the basic principles of microfluidic technology and summarize the recent progress in microfluidic devices to study bacterial spatial distribution and functions, as well as biological processes, such bacterial chemotaxis, biofilm streamers (BS), quorum sensing (QS), and HGT. The challenges in and future development of microfluidics for soil microbiological studies are also discussed. 
PubDate: 2022-09-01
- Continuous cropping of alfalfa (Medicago sativa L.) reduces bacterial
diversity and simplifies cooccurrence networks in aeolian sandy soil-
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Abstract: Abstract Alfalfa is a perennial herbaceous forage legume that is remarkably and negatively affected by monocropping. However, the contribution of the changes in bacterial communities to soil sickness in alfalfa have not been elucidated. Therefore, we investigated bacterial community structures in response to monocropped alfalfa along the chronosequence. Continuous cropping remarkably reduced bacterial alpha diversity and altered community structures, and soil pH, total P and available P were strongly associated with the changes of bacterial diversity and community structures. Intriguingly, 10 years of monocropped alfalfa might be a demarcation point separating soil bacterial community structures into two obvious groups that containing soil samples collected in less and more than 10 years. The relative abundances of copiotrophic bacteria of Actinobacteria and Gammaproteobacteria significantly increased with the extension of continuous cropping years, while the oligotrophic bacteria of Armatimonadetes, Chloroflexi, Firmicutes and Gemmatimonadetes showed the opposite changing patterns. Among those altered phyla, Actinobacteria, Chloroflexi, Alphaproteobacteria and Acidobacteria were the most important bacteria which contributed 50.86% of the community variations. Additionally, the relative abundances of nitrogen fixation bacteria of Bradyrhizobium and Mesorhizobium obviously increased with continuous cropping years, while the abundances of Arthrobacter, Bacillus, Burkholderiaceae and Microbacterium with potential functions of solubilizing phosphorus and potassium remarkably decreased after long-term continuous cropping. Furthermore, bacterial cooccurrence patterns were significantly influenced by continuous cropping years, with long-term monocropped alfalfa simplifying the complexity of the cooccurrence networks. These findings enhanced our understandings and provided references for forecasting how soil bacterial communities responds to monocropped alfalfa. 
PubDate: 2022-06-01
- Rhizosphere bacteria degrade auxin to promote root growth
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PubDate: 2022-06-01
- The rhizosphere effect on soil gross nitrogen mineralization: A
meta-analysis-
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Abstract: Abstract Rhizosphere effects play crucial roles in determining soil carbon (C) and nitrogen (N) cycling. However, the rhizosphere effect on soil gross nitrogen (N) mineralization (Nmin) has not been quantitatively assessed on the global scale. Here we performed a meta-analysis of compiled data from 24 publications and 37 species to synthesize the rhizosphere effect on soil gross Nmin and its influencing factors. We found that the rhizosphere effect significantly enhanced soil gross Nmin by 81% on average. Such rhizosphere effect was significantly higher in woody species than in nonwoody species, and higher in ECM (ectomycorrhizal) associated species than in AM (arbuscular mycorrhizal) associated species. Moreover, the variations of the rhizosphere effect on soil gross Nmin were correlated with those on soil C mineralization, phenol oxidase activity and root biomass rather than with other plant (growth form and mycorrhizal association) and climatic (mean annual temperature and precipitation) factors. These results support the ‘microbial activation’ and ‘microbial N mining’ hypotheses of rhizosphere effects and indicate the coupling of soil C and gross N mineralization in the rhizosphere. Overall, these findings provide novel insights into the rhizosphere effect on soil gross Nmin among plant growth forms and mycorrhizal associations, and improve our mechanistic understanding of soil N dynamics in the rhizosphere. 
PubDate: 2022-06-01
- Research trends of microplastics in the soil environment: Comprehensive
screening of effects-
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Abstract: Abstract We collated and synthesized previous studies that reported the impacts of microplastics on soil parameters. The data were classified and integrated to screen for the proportion of significant effects, then we suggest several directions to alleviate the current data limitation in future experiments. We compiled 106 datasets capturing significant effects, which were analyzed in detail. We found that polyethylene and pellets (or powders) were the most frequently used microplastic composition and shape for soil experiments. The significant effects mainly occurred in broad size ranges (0.1–1 mm) at test concentrations of 0.1%–10% based on soil dry weight. Polyvinyl chloride and film induced significant effects at lower concentrations compared to other compositions and shapes, respectively. We adopted a species sensitivity distribution (SSD) and soil property effect distribution (SPED) method using available data from soil biota, and for soil properties and enzymes deemed relevant for microplastic management. The predicted-no-effect-concentration (PNEC)-like values needed to protect 95% of soil biota and soil properties was estimated to be between 520 and 655 mg kg−1. This study was the first to screen microplastic levels with a view toward protecting the soil system. Our results should be regularly updated (e.g., quarterly) with additional data as they become available. 
PubDate: 2022-06-01
- Fungi dominate denitrification when Chinese milk vetch green manure is
used in paddy soil-
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Abstract: Abstract Fungi play an important role in soil nitrous oxide (N2O) emission in many agricultural soil systems. However, the effect of fungi on N2O emission in Chinese milk vetch (CMV)-containing soils has not been examined sufficiently. This study investigated the contribution of bacteria and fungi to soil N2O emission in CMV-amended soils. We compared soils from an experimental field in the Fujian Academy of Agricultural Sciences that had been treated with 30 000 kg of CMV per 667 m2 per year with one that was not treated with CMV. We incubated soil using cycloheximide and streptomycin to differentiate fungal and bacterial N2O emissions, respectively. Quantitative PCR (qPCR) was performed to investigate bacterial and fungal abundances in the two agricultural soil ecosystems. The contribution of fungi to soil N2O emission in CMV-amended soils was greater than that in non-CMV-amended paddy soils, with fungi accounting for more than 56% of the emissions in CMV-amended soils. Quantitative PCR showed that the ratio of the internal transcribed spacer to 16S rDNA was significantly higher in CMV-amended soils than in non-CMV-amended paddy soils. Furthermore, soil properties, such as pH (P<0.05) and NH4+ concentration (P<0.05), significantly and negatively affected N2O emission by fungi in soil, whereas the total organic carbon (P<0.05) and NO3− concentration (P<0.05) showed significant positive effects. Fungi may be important contributors to N2O production in CMV-amended soils, which may create challenges for mitigating N2O production. 
PubDate: 2022-06-01
- Effects of acid deposition on the avoidance behavior of Folsomia candida
(Collembola, Isotomidae)-
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Abstract: Abstract Excessive acid deposition causes soil acidification, and changes the soil microhabitat, thus affecting the survival and reproduction of soil organisms. Folsomia candida (Collembola, Isotomidae), as a model organism, is widely used to assess the chemical toxicity in soil, and its avoidance response can indicate the environmental changes. In this study, we used Folsomia candida to assess the risks of acid deposition on soil ecosystems. Different pH (3.0, 3.5, 4.0, 4.5, 5.0, and 5.5) treatments were set up in petri dish experiments, and the avoidance behavior of Folsomia candida was measured after 12, 24, and 48 h exposure to the pH conditions. The results indicated that (1) both the exposure duration and pH level influenced avoidance behavior of collembolan. (2) After 12 h exposure, most of the individuals showed avoidance behavior but without significant differences among the treatments. (3) After 24 h exposure, significant avoidance behavior was observed at pH 3.0, 3.5, and 4.0. (4) After 48 h exposure, avoidance behavior was found in all treatment conditions except for pH 5.5. This study clarified the direct responses of soil fauna to acid deposition, and indicated that both pH and length of exposure influenced the avoidance behavior of Folsomia candida. During the experimental period, the collembolan reacted negatively and showed consistent avoidance behavior at pH 3.0, 3.5, and 4.0. Reversed avoidance behavior was apparent between pH 4.5 and 5.0 and not observed at pH 5.5, indicating that the latter was the preferred pH environment. 
PubDate: 2022-06-01
- Bacterial and eukaryotic community interactions might contribute to shrimp
culture pond soil ecosystem at different culture stages-
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Abstract: Abstract Sedimentary bacterial and eukaryotic communities are major components of the aquatic ecosystem. Revealing the linkages between their community structure and interactions is crucial to understand the diversity and functions of aquatic and soil ecosystems. However, how their diversity and assembly contribute to their interactions on time scale is unclear. This study examined sedimentary bacterial and eukaryotic communities in shrimp culture ponds at different culture stages. The most abundant bacteria were Proteobacteria (38.27%), whereas the most abundant eukaryotes were Chytridiomycota (27.48%). Bacterial and eukaryotic diversities were correlated (P<0.05), implying the strong interactions between bacteria and eukaryotes. Results showed that the bacterial and eukaryotic communities became increasingly similar on a local scale along with the shrimp culture. Only the eukaryotic community significantly increased in similarity along with the shrimp culture (P <0.05), suggesting that the sedimentary eukaryotic community structure is sensitive under shrimp culture. Co-occurrence network modeling indicated that positive microbial interactions were dominant. The homogeneous selection was the major driver of community assembly. Bacterial diversity negatively correlated with operational taxonomic units and positive links in networks (P<0.05), whereas eukaryotic diversities positively correlated with positive links in networks (P<0.05). This study broadens our knowledge about sedimentary microbial diversity, community assembly, and interaction patterns on time scale, providing a reference for the sustainable management in aquaculture production. 
PubDate: 2022-06-01
- Perspectives on ecological risks of microplastics and phthalate acid
esters in crop production systems-
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Abstract: Abstract Microplastics (MPs) and phthalate acid esters (PAEs) co-occur as emerging contaminants of global importance. Their abundance in soil is of increasing concern as plastic-intensive practices continue. Mulching with plastic films, inclusion in fertilizers, composts, sludge application, and wastewater irrigation are all major and common sources of MPs and PAEs in soil. Here, we review studies on the concentration and effects of MPs and PAEs in soil. While there is limited research on the interactions between MPs and PAEs in agroecosystems, there is evidence to suggest they could mutually affect soil ecology and plant growth. Therefore, we propose new research into 1) establishing an efficient, accurate, and simple method to quantify different types of microplastics in soils and plants; 2) exploring the behavior and understanding the mechanisms of co-transfer, transformation, and interactions with soil biota (especially in vegetable production systems); 3) assessing the risk and consequences of combined and discreet impacts of MPs and PAEs on plants and soil biota, and 4) preventing or reducing the transfer of MPs and PAEs into- and within- the food chain. 
PubDate: 2022-06-01
- Invasibility and recoverability of a plant community following invasion
depend on its successional stages-
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Abstract: Abstract Exotic species invasion represent important causes of harming the structure, function, and ecological environment in ecosystems. Yet, knowledge remains limited on the invasibility (invasion advantage of exotic species) and recoverability (recovery ability of native species) of a plant community following invasion depend on its successional stages. We selected three grasses of Setaria viridis, Artemisia gmelinii, and Bothriochloa ischemum representing early (E), middle (M), and late (L) successional species, respectively. Meanwhile, the grasses of Panicum virgatum was selected to represent exotic species (invasion species). Three types of soil were collected to treat the three E, M, and L successional species, and one type of soil was collected to treat the exotic species. We compared the performance of the three native plant species and one exotic species grown in their “own” and “other” soils in a 2-year greenhouse experiment. Our study showed that exotic species performed better in soils of E and M successional species than in the soil of L successional species. After exotic species removed, E and M successional species exhibited poor growth in the soil of exotic species, while that of L successional species performed poor in field exotic species soils, but performed better in soils disturbed by exotic species. Our study demonstrated that the invasibility and recoverability of native plant communities changed with vegetation succession. 
PubDate: 2022-06-01
- Activity-density and spatial distribution of termites on a fine-scale in a
tropical rainforest in Xishuangbanna, southwest China-
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Abstract: Abstract The community composition and activity-density of termites can influence nutrient cycling and other ecological functions. However, the spatial distribution and the activity-density of termites on a fine-scale in tropical forests are still unknown. We checked the spatial distribution patterns of the feeding groups and species of termites and their co-occurrence pattern in a 1-ha (100 m × 100 m) plot, and their correlation with the environmental factors. We used a standard protocol to collect termite assemblages and classified them into five feeding groups based on their preferred diet: fungus growers, litter feeders, soil feeders, soil-wood feeders, and wood feeders. We measured the environmental factors: soil pH, litter mass, aboveground plant biomass, and topographic position index (TPI). Soil-wood feeders showed the highest activity-density, followed by wood feeders, fungus growers, soil feeders, and litter feeders. Soil-wood feeders and fungus growers demonstated a strong correlation while litter feeders showed weak correlations with other feeding groups. Termite feeding groups and most of the termite species displayed a positive association with the high TPI and the low soil pH patches. Our results indicated that the examined environmental factors influenced the termite community assemblages and distribution patterns on a fine-scale in tropical rainforests. 
PubDate: 2022-05-04
- Influencing factors and partitioning methods of carbonate contribution to
CO2 emissions from calcareous soils-
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Abstract: Abstract In calcareous soils, recent studies have shown that soil-derived CO2 originates from both soil organic carbon (SOC) decomposition and soil inorganic carbon (SIC) dissolution, a fact often ignored in earlier studies. This may lead to overestimation of the CO2 emissions from SOC decomposition. In calcareous soils, there is a chemical balance between precipitation and dissolution of CaCO3-CO2-HCO 3 − , which is affected by soil environmental factors (moisture, temperature, pH and depth), root growth (rhizosphere effect) and agricultural measures (organic materials input, nitrogen fertilization and straw removal). In this paper, we first introduced the contribution of SIC dissolution to CO2 emissions from calcareous soils and their driving factors. Second, we reviewed the methods to distinguish two CO2 sources released from calcareous soils and quantify the 13C fractionation coefficient between SIC and SIC-derived CO2 and between SOC and SOC-derived CO2, and to partition three CO2 sources released from soils with plants and organic materials input. Finally, we proposed methods for accurately distinguishing three CO2 sources released from calcareous soils. This review helps to improve the accuracy of soil C balance assessment in calcareous soils, and also proposes the direction of further investigations on SIC-derived CO2 emissions responses to abiotic factors and agricultural measures. 
PubDate: 2022-04-25
- Effects of lead pollution on soil microbial community diversity and
biomass and on invertase activity-
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Abstract: Abstract Lead (Pb) pollution is one of the most widespread and harmful environmental problems worldwide. Determination of changes in soil properties and microbial functional diversity due to land use is needed to establish a basis for remediation of soil pollution. This study aimed to investigate soils contaminated by Pb from different sources and to analyze the functional diversity and metabolism of soil microbial communities using Biolog technology. Pb pollution (>300 mg kg−1) significantly influenced the diversity and metabolic functions of soil microbial communities. Specifically, Pb contamination significantly reduced soil microbial biomass carbon (C) and nitrogen (N) levels and catalase activity while increasing invertase activity. Furthermore, Biolog EcoPlate assays revealed that Pb pollution reduced the general activities of soil microorganisms, suppressing their ability to utilize C sources. In Pb-contaminated areas lacking vegetation cover, Shannon, Simpson, and McIntosh diversity indices of soil microorganisms were significantly reduced. The microbial diversity and biomass C and N levels were affected by land use and soil properties, respectively, whereas soil enzyme activity was primarily affected by the interaction between land use and soil properties. Our results provide a reference and a theoretical basis for developing soil quality evaluation and remediation strategies. 
PubDate: 2022-04-12
- Use of flue gas desulfurization gypsum to reduce dissolved phosphorus in
runoff and leachate from two agricultural soils-
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Abstract: Abstract Controlling dissolved phosphorus (DP) loss from high P soil to avoid water eutrophication is a worldwide high priority. A greenhouse study was conducted in which flue gas desulfurization gypsum (FGDG) was applied by using different application methods and rates to two agricultural soils. Phosphorus fertilizer was incorporated into the soils at 2.95 g kg−1 to simulate soil with high P levels. The FGDG was then applied at amounts of 0, 1.5, and 15 g kg−1 soil on either the soil surface or mixed throughout the soil samples to simulate no-tillage and tillage, respectively. Ryegrass was planted after treatment application. The study showed that FGDG reduced runoff DP loss by 33% and leachate DP loss 38% in silt loam soil, and runoff DP loss 46% and leachate DP loss 14% in clay loam soil, at the treatment of 15 g kg−1 FGDG. Mixing applied method (tillage) provided strong interaction with higher FGDG. To overall effect, the mixing-applied method performed better in controlling DP loss from silt loam soil, while surface-applied (no tillage) showed its advantage in controlling DP loss from clay loam soil. In practice it is necessary to optimize FGDG concentrations, application methods, and DP sources (runoff or leachate) to get maximized benefits of FGDG application. The FGDG application had no negative effects on the soil and ryegrass. 
PubDate: 2022-04-12
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