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Matthias C. Rillig - One of the best experts on this subject based on the ideXlab platform.
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Effects of Microplastic Fibers on Soil Aggregation and Enzyme Activities Are Organic Matter Dependent
Frontiers in Environmental Science, 2021Co-Authors: Yun Liang, Anika Lehmann, Eva F. Leifheit, Gaowen Yang, Matthias C. RilligAbstract:Microplastic as an anthropogenic pollutant accumulates in terrestrial ecosystems over time, threatening Soil quality and health, for example by decreasing aggregate stability. Organic matter addition is an efficient approach to promote aggregate stability, yet little is known about whether microplastic can reduce the beneficial effect of organic matter on aggregate stability. We investigated the impacts of microplastic fibers in the presence or absence of different organic materials by carrying out a Soil incubation experiment. This experiment was set up as a fully factorial design containing all combinations of microplastic fibers (no microplastic fiber addition, two different types of polyester fibers, and polyacrylic) and organic matter (no organic matter addition, Medicago lupulina leaves, Plantago lanceolata leaves, wheat straw, and hemp stems). We evaluated the percentage of water-stable aggregates (WSA) and activities of four Soil enzymes (β-glucosidase, β-D-celluliosidase, N-acetyl-b-glucosaminidase, phosphatase). Organic matter addition increased WSA and enzyme activities, as expected. In particular, Plantago or wheat straw addition increased WSA and enzyme activities by 224.77 or 281.65% and 298.51 or 55.45%, respectively. Microplastic fibers had no effect on WSA and enzyme activities in the Soil without organic matter addition, but decreased WSA and enzyme activities by 26.20 or 37.57% and 23.85 or 26.11%, respectively, in the presence of Plantago or wheat straw. Our study shows that the effects of microplastic fibers on Soil Aggregation and enzyme activities are organic matter dependent. A possible reason is that Plantago and wheat straw addition stimulated Soil Aggregation to a greater degree, resulting in more newly formed aggregates containing microplastic, the incorporated microplastic fibers led to less stable aggregates, and decrease in enzyme activities This highlights an important aspect of the context dependency of microplastic effects in Soil and on Soil health. Our results also suggest risks for Soil stability associated with organic matter additions, such as is common in agroecosystems, when microplastics are present.
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Protists and collembolans alter microbial community composition, C dynamics and Soil Aggregation in simplified consumer–prey systems
Biogeosciences, 2020Co-Authors: Amandine Erktan, Matthias C. Rillig, Andrea Carminati, Alexandre Jousset, Stefan ScheuAbstract:Abstract. Microbes play an essential role in Soil functioning including biogeochemical cycling and Soil aggregate formation. Yet, a major challenge is to link microbes to higher trophic levels and assess consequences for Soil functioning. Here, we aimed to assess how microbial consumers modify microbial community composition (PLFA markers), as well as C dynamics (microbial C use, SOC concentration and CO2 emission) and Soil Aggregation. We rebuilt two simplified Soil consumer–prey systems: a bacterial-based system comprising amoebae (Acanthamoeba castellanii) feeding on a microbial community dominated by the free-living bacterium Pseudomonas fluorescens and a fungal-based system comprising collembolans (Heteromurus nitidus) grazing on a microbial community dominated by the saprotrophic fungus Chaetomium globosum. The amoeba A. castellanii did not affect microbial biomass and composition, but it enhanced the formation of Soil aggregates and tended to reduce their stability. Presumably, the dominance of P. fluorescens, able to produce antibiotic toxins in response to the attack by A. castellanii, was the main cause of the unchanged microbial community composition, and the release of bacterial extracellular compounds, such as long-chained polymeric substances or proteases, in reaction to predation was responsible for the changes in Soil Aggregation as a side effect. In the fungal system, collembolans significantly modified microbial community composition via consumptive and non-consumptive effects including the transport of microbes on the body surface. As expected, fungal biomass promoted Soil Aggregation and was reduced in the presence of H. nitidus. Remarkably, we also found an unexpected contribution of changes in bacterial community composition to Soil Aggregation. In both the bacterial and fungal systems, bacterial and fungal communities mainly consumed C from Soil organic matter (rather than the litter added). Increased fungal biomass was associated with an increased capture of C from added litter, and the presence of collembolans levelled off this effect. Neither amoebae nor collembolans altered SOC concentrations and CO2 production. Overall, the results demonstrated that trophic interactions are important for achieving a mechanistic understanding of biological contributions to Soil Aggregation and may occur without major changes in C dynamics and with or without changes in the composition of the microbial community.
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Bacterial and fungal predator – prey interactions modulate Soil Aggregation
2020Co-Authors: Amandine Erktan, Matthias C. Rillig, Andrea Carminati, Alexandre Jousset, Stefan ScheuAbstract:Abstract. The formation and stabilisation of Soil macro-aggregates protects Soils from erosion, a major worldwide threat on Soils. While the role of bacteria and fungi in Soil Aggregation is well established, how predators feeding on microbes modify Soil Aggregation has hardly been tested. Here, we studied how predators modulate the effect of microbial prey on Soil Aggregation. We focused on two predator – prey interactions: bacterial-based interactions comprising amoebae (Acanthamoeba castellanii) grazing on free-living bacteria (Pseudomonas fluorescens), and fungal-based interactions comprising collembolans (Heteromurus nitidus) grazing on saprotrophic fungi (Chaetomium globosum). We conducted a microcosm experiment lasting six weeks and assessed changes in Soil aggregate formation and stabilisation, together with modifications in Soil microbial communities (PLFAs). We further traced the food resource consumed by microbes using δ13C isotopic tracing. The protist A. castellanii increased the formation of Soil aggregates but decreased their stability, without affecting bacterial abundance and community composition, suggesting that the changes were due to amoebae-mediated changes in the production of bacterial mucilage. Saprotrophic fungi showed the highest positive effect on Soil aggregate formation and stabilisation, associated with a more efficient use of particulate organic carbon (chopped litter) added to the microcosms. Adding collembolans decreased the abundance of fungi and their ability to capture carbon of litter origin, with negative consequences on Soil Aggregation. Our work here has demonstrated that trophic interactions are important for achieving a mechanistic understanding of biological contributions to Soil Aggregation.
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Increasing Temperature and Microplastic Fibers Jointly Influence Soil Aggregation by Saprobic Fungi
Frontiers in Microbiology, 2019Co-Authors: Yun Liang, Max-bernhard Ballhausen, Ludo A. H. Muller, Anika Lehmann, Matthias C. RilligAbstract:Microplastic pollution and global warming are two aspects of global change that potentially influence Soil quality; yet little is known about their effects on Soil Aggregation, a key determinant of Soil quality. Given the importance of fungi for Soil Aggregation, we investigated the impacts of rising temperature and microplastic fibers on Aggregation by carrying out a Soil incubation experiment in which we inoculated Soil individually with specific strains of Soil saprobic fungi (Chaetomium elatum, Truncatella angustata, Fusarium redolens, Mucor fragilis, and Fusarium sp.). Our treatments were temperature (ambient temperature of 25℃ or temperature increased by 3℃, abruptly versus gradually) and microplastic fibers (control and 0.4% w/ w). We evaluated the percentage of water stable aggregates (WSA) and hydrolysis of fluorescein diacetate (FDA). Microplastic fiber addition was the main factor influencing the WSA, decreasing the percentage of WSA except in Soil incubated with M. fragilis, and mitigated the effects of temperature or even caused more pronounced decrease in WSA under elevated temperature. We also observed clear differences between temperature change patterns. Our study shows that the interactive effects of warming and microplastic fibers are important to consider when evaluating effects of global change on Soil Aggregation and potentially other Soil processes.
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Fungal traits important for Soil Aggregation
2019Co-Authors: Anika Lehmann, Weishuang Zheng, Masahiro Ryo, Katharina Soutschek, Rebecca Rongstock, Stefanie Maaß, Matthias C. RilligAbstract:Abstract Soil health and sustainability is essential for ecosystem functioning and human well-being. Soil structure, the complex arrangement of Soil into aggregates and pore spaces, is a key feature of Soils under the influence of Soil life. Soil biota, and among them filamentous saprobic fungi, have well-documented effects on Soil Aggregation. However, it is unclear what fungal properties, or traits, contribute to the overall positive effect on Soil Aggregation. So far, we lack a systematic investigation of a broad suite of fungal species for their trait expression and the relation of these traits to their Soil Aggregation capability. Here, we apply a trait-based approach to a set of 15 traits measured under standardized conditions on 31 fungal strains including Ascomycota, Basidiomycota and Mucoromycota, all isolated from the same Soil. We found a spectrum of Soil aggregate formation capability ranging from neutral to positive and large differences in trait expression among strains. We identified biomass density (positive effects), leucine aminopeptidase activity (negative effects) and phylogeny as important modulators of fungal aggregate formation capability. Our results point to a typical suite of traits characterizing fungi that are good Soil aggregators; this could inform screening for fungi to be used in biotechnological applications, and illustrates the power of employing a trait-based approach to unravel biological mechanisms of Soil Aggregation, which could now be extended to other organism groups.
Anika Lehmann - One of the best experts on this subject based on the ideXlab platform.
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Effects of Microplastic Fibers on Soil Aggregation and Enzyme Activities Are Organic Matter Dependent
Frontiers in Environmental Science, 2021Co-Authors: Yun Liang, Anika Lehmann, Eva F. Leifheit, Gaowen Yang, Matthias C. RilligAbstract:Microplastic as an anthropogenic pollutant accumulates in terrestrial ecosystems over time, threatening Soil quality and health, for example by decreasing aggregate stability. Organic matter addition is an efficient approach to promote aggregate stability, yet little is known about whether microplastic can reduce the beneficial effect of organic matter on aggregate stability. We investigated the impacts of microplastic fibers in the presence or absence of different organic materials by carrying out a Soil incubation experiment. This experiment was set up as a fully factorial design containing all combinations of microplastic fibers (no microplastic fiber addition, two different types of polyester fibers, and polyacrylic) and organic matter (no organic matter addition, Medicago lupulina leaves, Plantago lanceolata leaves, wheat straw, and hemp stems). We evaluated the percentage of water-stable aggregates (WSA) and activities of four Soil enzymes (β-glucosidase, β-D-celluliosidase, N-acetyl-b-glucosaminidase, phosphatase). Organic matter addition increased WSA and enzyme activities, as expected. In particular, Plantago or wheat straw addition increased WSA and enzyme activities by 224.77 or 281.65% and 298.51 or 55.45%, respectively. Microplastic fibers had no effect on WSA and enzyme activities in the Soil without organic matter addition, but decreased WSA and enzyme activities by 26.20 or 37.57% and 23.85 or 26.11%, respectively, in the presence of Plantago or wheat straw. Our study shows that the effects of microplastic fibers on Soil Aggregation and enzyme activities are organic matter dependent. A possible reason is that Plantago and wheat straw addition stimulated Soil Aggregation to a greater degree, resulting in more newly formed aggregates containing microplastic, the incorporated microplastic fibers led to less stable aggregates, and decrease in enzyme activities This highlights an important aspect of the context dependency of microplastic effects in Soil and on Soil health. Our results also suggest risks for Soil stability associated with organic matter additions, such as is common in agroecosystems, when microplastics are present.
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Increasing Temperature and Microplastic Fibers Jointly Influence Soil Aggregation by Saprobic Fungi
Frontiers in Microbiology, 2019Co-Authors: Yun Liang, Max-bernhard Ballhausen, Ludo A. H. Muller, Anika Lehmann, Matthias C. RilligAbstract:Microplastic pollution and global warming are two aspects of global change that potentially influence Soil quality; yet little is known about their effects on Soil Aggregation, a key determinant of Soil quality. Given the importance of fungi for Soil Aggregation, we investigated the impacts of rising temperature and microplastic fibers on Aggregation by carrying out a Soil incubation experiment in which we inoculated Soil individually with specific strains of Soil saprobic fungi (Chaetomium elatum, Truncatella angustata, Fusarium redolens, Mucor fragilis, and Fusarium sp.). Our treatments were temperature (ambient temperature of 25℃ or temperature increased by 3℃, abruptly versus gradually) and microplastic fibers (control and 0.4% w/ w). We evaluated the percentage of water stable aggregates (WSA) and hydrolysis of fluorescein diacetate (FDA). Microplastic fiber addition was the main factor influencing the WSA, decreasing the percentage of WSA except in Soil incubated with M. fragilis, and mitigated the effects of temperature or even caused more pronounced decrease in WSA under elevated temperature. We also observed clear differences between temperature change patterns. Our study shows that the interactive effects of warming and microplastic fibers are important to consider when evaluating effects of global change on Soil Aggregation and potentially other Soil processes.
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Fungal traits important for Soil Aggregation
2019Co-Authors: Anika Lehmann, Weishuang Zheng, Masahiro Ryo, Katharina Soutschek, Rebecca Rongstock, Stefanie Maaß, Matthias C. RilligAbstract:Abstract Soil health and sustainability is essential for ecosystem functioning and human well-being. Soil structure, the complex arrangement of Soil into aggregates and pore spaces, is a key feature of Soils under the influence of Soil life. Soil biota, and among them filamentous saprobic fungi, have well-documented effects on Soil Aggregation. However, it is unclear what fungal properties, or traits, contribute to the overall positive effect on Soil Aggregation. So far, we lack a systematic investigation of a broad suite of fungal species for their trait expression and the relation of these traits to their Soil Aggregation capability. Here, we apply a trait-based approach to a set of 15 traits measured under standardized conditions on 31 fungal strains including Ascomycota, Basidiomycota and Mucoromycota, all isolated from the same Soil. We found a spectrum of Soil aggregate formation capability ranging from neutral to positive and large differences in trait expression among strains. We identified biomass density (positive effects), leucine aminopeptidase activity (negative effects) and phylogeny as important modulators of fungal aggregate formation capability. Our results point to a typical suite of traits characterizing fungi that are good Soil aggregators; this could inform screening for fungi to be used in biotechnological applications, and illustrates the power of employing a trait-based approach to unravel biological mechanisms of Soil Aggregation, which could now be extended to other organism groups.
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Abiotic and Biotic Factors Influencing the Effect of Microplastic on Soil Aggregation
Soil Systems, 2019Co-Authors: Anika Lehmann, Katharina Fitschen, Matthias C. RilligAbstract:Plastic is an anthropogenic, ubiquitous and persistent contaminant accumulating in our environment. The consequences of the presence of plastics for Soils, including Soil biota and the processes they drive, are largely unknown. This is particularly true for microplastic. There is only little data available on the effect of microplastics on key Soil processes, including Soil Aggregation. Here, we investigated the consequences of polyester microfiber contamination on Soil Aggregation of a sandy Soil under laboratory conditions. We aimed to test if the microfiber effects on Soil Aggregation were predominantly physical or biological. We found that Soil biota addition (compared to sterile Soil) had a significant positive effect on both the formation and stabilization of Soil aggregates, as expected, while wet-dry cycles solely affected aggregate formation. Polyester microfiber contamination did not affect the formation and stability of aggregates. But in the presence of Soil biota, microfibers reduced Soil aggregate stability. Our results show that polyester microfibers have the potential to alter Soil structure, and that these effects are at least partially mediated by Soil biota.
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Soil biota contributions to Soil Aggregation
Nature Ecology and Evolution, 2017Co-Authors: Anika Lehmann, Weishuang Zheng, Matthias C. RilligAbstract:Humankind depends on the sustainability of Soils for its survival and well-being. Threatened by a rapidly changing world, our Soils suffer from degradation and biodiversity loss, making it increasingly important to understand the role of Soil biodiversity in Soil Aggregation—a key parameter for Soil sustainability. Here, we provide evidence of the contribution of Soil biota to Soil Aggregation on macro- and microaggregate scales, and evaluate how specific traits, Soil biota groups and species interactions contribute to this. We conducted a global meta-analysis comprising 279 Soil biota species. Our study shows a clear positive effect of Soil biota on Soil Aggregation, with bacteria and fungi generally appearing to be more important for Soil Aggregation than Soil animals. Bacteria contribute strongly to both macro- and microaggregates while fungi strongly affect macroAggregation. Motility, body size and population density were important traits modulating effect sizes. Investigating species interactions across major taxonomic groups revealed their beneficial impact on Soil Aggregation. At the broadest level, our results highlight the need to consider biodiversity as a causal factor in Soil Aggregation. This will require a shift from the current management and physicochemical perspective to an approach that fully embraces the significance of Soil organisms, their diversity and interactions. The structuring of Soil into distinct aggregates is a key element in biogeochemical cycling. Here, a meta-analysis reveals a strong positive effect of Soil biota on Soil Aggregation, with the largest influence coming from bacteria and fungi.
Xinhua Peng - One of the best experts on this subject based on the ideXlab platform.
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effects of residue stoichiometric biochemical and c functional features on Soil Aggregation during decomposition of eleven organic residues
Catena, 2021Co-Authors: Shiping Liu, M Halder, Zengxiang Zhang, Z C Guo, Xinhua PengAbstract:Abstract Soil Aggregation is deeply impacted by the quality of organic materials. However, the organic material features that control Soil Aggregation dynamics are still largely unknown. In this study, a total of 11 organic residues including vetch (alfalfa, hairy, and Chinese milk), straw (rice, maize, wheat, miscanthus, soybean, and sorghum) and manures (cattle and pig) were characterized by stoichiometric, biochemical and C functional features. The Soil respiration, mean weight diameter (MWD) and glomalin-related Soil protein (GRSP) levels were measured during 56 d of incubation. The results showed that stoichiometric features had no impact on Soil respiration and aggregate stability except the N content. Residue decomposition was positively affected by soluble sugars but negatively affected by lignin and cellulose in the first 14 d (P straw > vetch. The GRSP content had a negative effect on the MWD up to 28 d (P
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does animal manure application improve Soil Aggregation insights from nine long term fertilization experiments
Science of The Total Environment, 2019Co-Authors: Zichun Guo, Jiabao Zhang, Jun Fan, Xueyun Yang, Xiaori Han, Daozhong Wang, Ping Zhu, Xinhua PengAbstract:Abstract Manure application is widely recognized as a method of improving Soil structure and Soil fertility due to additional organic matter and nutrient inputs. However, the salinity of animal manure may have a detrimental effect on Soil Aggregation. The objective of this study was to determine the effects of long-term animal manure application on Soil Aggregation, binding agents (Soil organic carbon, SOC and glomalin-related Soil protein, GRSP), and dispersing agents (e.g., Na+) and their relationships based on nine long-term fertilization experiments (12 to 39 yr) across China. The two red Soil experiments (Qiyang, QY and Jinxian, JX) and one paddy Soil experiment in Jinxian (JX-P) were conducted in southern China (precipitation above 1200 mm yr−1), whereas the other six experiments were established in semi-humid or arid regions in China with precipitation in the range of 500–900 mm yr−1. Each experiment included three treatments as follows: no fertilization (Control), inorganic fertilizer (NP or NPK), and a combination of inorganic fertilizer and animal manure (NPM or NPKM). Long-term animal manure application not only significantly increased the biological binding agents (i.e., SOC and GRSP) in the nine experiments but also considerably increased the dispersing agents (i.e., exchangeable Na+) (P
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Biochar enhances Soil hydraulic function but not Soil Aggregation in a sandy loam
European Journal of Soil Science, 2018Co-Authors: Hu Zhou, Huajun Fang, Q. Zhang, Q. Wang, Chong Chen, Sacha J. Mooney, Xinhua PengAbstract:© 2018 British Society of Soil Science Biochar has the potential to modify Soil structure and Soil hydraulic properties because of its small particle density, highly porous structure, grain size distribution and surface chemistry. However, knowledge of the long-term effects of biochar on Soil physical properties under field conditions is limited. Using an 8-year field trial, we investigated the effects of successive additions of high-dose maize-cob-derived biochar (9.0 t ha −1 year −1 , HB), low-dose maize-cob-derived biochar (4.5 t ha −1 year −1 , LB), straw return (SR) and control (no biochar or straw, CK) on Soil aggregate distribution, three-dimensional (3-D) pore structure, hydraulic conductivity and water retention in the upper 10 cm of a sandy loam Soil from the North China Plain. Results showed that LB and HB treatments increased Soil organic C content by 61.0–116.3% relative to CK. Interestingly, biochar amendment did not enhance the proportion of macroaggregates (> 2 and 0.25–2 mm) or aggregate stability, indicating limited positive effects on Soil Aggregation. The HB treatment decreased Soil bulk density, and increased total porosity and macroporosity (> 30 μm). The retention of Soil water, including gravitational water (0–33 kPa), capillary water (33–3100 kPa) and hygroscopic water (> 3100 kPa), was improved under HB Soil. The HB and LB treatments increased plant-available water content by 17.8 and 10.1%, respectively, compared with CK. In contrast, SR showed no significant increase in Soil porosity and water retention capacity but improved the water stability of macroaggregates. We concluded that biochar used in the coarse-textured Soil enhanced saturated hydraulic conductivity and water-holding capacity, but did not improve Soil Aggregation. Highlights: Pore structure and hydraulic properties were studied in an 8-year biochar-amended sandy loam. HB (high-dose biochar) increased total Soil porosity and CT-identified macroporosity (> 30 μm). Water retention improved under HB Soil. Biochar addition had no effect on the formation of macroaggregates.
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Long-term animal manure application promoted biological binding agents but not Soil Aggregation in a Vertisol
Soil and Tillage Research, 2018Co-Authors: Zichun Guo, Z.b. Zhang, Hu Zhou, M.t. Rahman, D.z. Wang, X.s. Guo, Xinhua PengAbstract:Abstract To improve Soil Aggregation through proper fertilization is very important for enhancing Soil quality and crop productivity. However, the response of Soil Aggregation varies with the fertilization practices. The objective of this study was to determine the effects of long-term application of inorganic fertilizer, straw and manure on water-stable aggregate distribution (>2 mm, 0.25–2.0 mm, 0.053–0.25 mm, and P + . Consequently, the straw incorporation promoted the formation of >2 mm macroaggregates significantly ( P P > 0.05). The SOC, GRSP and MBC played an important role in the formation and stabilization of 0.25–2.0 mm aggregates. Our results indicate that animal manure may degrade Soil structure due to the high salt content but straw incorporation is a judicious practice for sustainable agriculture in the Vertisol.
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effects of organic and inorganic fertilization on Soil Aggregation in an ultisol as characterized by synchrotron based x ray micro computed tomography
Geoderma, 2013Co-Authors: Hu Zhou, Xinhua Peng, E Perfect, Tiqiao 肖体乔 Xiao, Guanyun PengAbstract:Long-term fertilization practices generally improve Soil Aggregation through associated increases in organic matter over time. However, the influence of organic versus inorganic fertilization on aggregate structures may be quite different. In this paper, we aimed to quantify the three-dimensional (3D) microstructure of Soil aggregates as influenced by different long-term fertilization practices. Soil aggregates with diameters of approximately 5 mm were collected from an Ultisol with a long-term fertilization trial established in 1986. The treatments were no fertilizer (CK), chemical fertilizer (NPK), and chemical fertilizer plus organic manure (NPK + OM). The aggregate microstructure was determined with synchrotron based X-ray micro-computed tomography (SR-mu CT) and digital image analysis techniques. Mean corn yields and Soil organic carbon were the highest in NPK + OM, followed by NPK and then by CK. Aggregate stability was highest in NPK + OM, and lowest in NPK. The number of pores, number of pore throats, and number of paths between adjacent nodal pores were all significantly decreased by the NPK + OM treatment relative to the NPK and CK treatments. However, microstructural pore properties were mostly not different between NPK and CM treatments. This study demonstrates that organic fertilization can improve Soil Aggregation, while inorganic fertilization is ineffective, even after 25 years. The different mechanisms by which organic and inorganic fertilization practices influence Soil Aggregation deserve further investigation. (c) 2012 Elsevier B.V. All rights reserved.
Weishuang Zheng - One of the best experts on this subject based on the ideXlab platform.
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Fungal traits important for Soil Aggregation
2019Co-Authors: Anika Lehmann, Weishuang Zheng, Masahiro Ryo, Katharina Soutschek, Rebecca Rongstock, Stefanie Maaß, Matthias C. RilligAbstract:Abstract Soil health and sustainability is essential for ecosystem functioning and human well-being. Soil structure, the complex arrangement of Soil into aggregates and pore spaces, is a key feature of Soils under the influence of Soil life. Soil biota, and among them filamentous saprobic fungi, have well-documented effects on Soil Aggregation. However, it is unclear what fungal properties, or traits, contribute to the overall positive effect on Soil Aggregation. So far, we lack a systematic investigation of a broad suite of fungal species for their trait expression and the relation of these traits to their Soil Aggregation capability. Here, we apply a trait-based approach to a set of 15 traits measured under standardized conditions on 31 fungal strains including Ascomycota, Basidiomycota and Mucoromycota, all isolated from the same Soil. We found a spectrum of Soil aggregate formation capability ranging from neutral to positive and large differences in trait expression among strains. We identified biomass density (positive effects), leucine aminopeptidase activity (negative effects) and phylogeny as important modulators of fungal aggregate formation capability. Our results point to a typical suite of traits characterizing fungi that are good Soil aggregators; this could inform screening for fungi to be used in biotechnological applications, and illustrates the power of employing a trait-based approach to unravel biological mechanisms of Soil Aggregation, which could now be extended to other organism groups.
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Soil biota contributions to Soil Aggregation
Nature Ecology and Evolution, 2017Co-Authors: Anika Lehmann, Weishuang Zheng, Matthias C. RilligAbstract:Humankind depends on the sustainability of Soils for its survival and well-being. Threatened by a rapidly changing world, our Soils suffer from degradation and biodiversity loss, making it increasingly important to understand the role of Soil biodiversity in Soil Aggregation—a key parameter for Soil sustainability. Here, we provide evidence of the contribution of Soil biota to Soil Aggregation on macro- and microaggregate scales, and evaluate how specific traits, Soil biota groups and species interactions contribute to this. We conducted a global meta-analysis comprising 279 Soil biota species. Our study shows a clear positive effect of Soil biota on Soil Aggregation, with bacteria and fungi generally appearing to be more important for Soil Aggregation than Soil animals. Bacteria contribute strongly to both macro- and microaggregates while fungi strongly affect macroAggregation. Motility, body size and population density were important traits modulating effect sizes. Investigating species interactions across major taxonomic groups revealed their beneficial impact on Soil Aggregation. At the broadest level, our results highlight the need to consider biodiversity as a causal factor in Soil Aggregation. This will require a shift from the current management and physicochemical perspective to an approach that fully embraces the significance of Soil organisms, their diversity and interactions. The structuring of Soil into distinct aggregates is a key element in biogeochemical cycling. Here, a meta-analysis reveals a strong positive effect of Soil biota on Soil Aggregation, with the largest influence coming from bacteria and fungi.
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Soil biota contributions to Soil Aggregation.
Nature ecology & evolution, 2017Co-Authors: Anika Lehmann, Weishuang Zheng, Matthias C. RilligAbstract:Humankind depends on the sustainability of Soils for its survival and well-being. Threatened by a rapidly changing world, our Soils suffer from degradation and biodiversity loss, making it increasingly important to understand the role of Soil biodiversity in Soil Aggregation-a key parameter for Soil sustainability. Here, we provide evidence of the contribution of Soil biota to Soil Aggregation on macro- and microaggregate scales, and evaluate how specific traits, Soil biota groups and species interactions contribute to this. We conducted a global meta-analysis comprising 279 Soil biota species. Our study shows a clear positive effect of Soil biota on Soil Aggregation, with bacteria and fungi generally appearing to be more important for Soil Aggregation than Soil animals. Bacteria contribute strongly to both macro- and microaggregates while fungi strongly affect macroAggregation. Motility, body size and population density were important traits modulating effect sizes. Investigating species interactions across major taxonomic groups revealed their beneficial impact on Soil Aggregation. At the broadest level, our results highlight the need to consider biodiversity as a causal factor in Soil Aggregation. This will require a shift from the current management and physicochemical perspective to an approach that fully embraces the significance of Soil organisms, their diversity and interactions.
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Ectomycorrhizal fungi in association with Pinus sylvestris seedlings promote Soil Aggregation and Soil water repellency
Soil Biology and Biochemistry, 2014Co-Authors: Weishuang Zheng, E. Kathryn Morris, Matthias C. RilligAbstract:Research on fungal effects on Soil Aggregation has been heavily biased towards arbuscular mycorrhiza. Even though ectomycorrhizal fungi are thought to be as important as arbuscular mycorrhizal fungi and saprotrophic fungi in contributing to Soil structure, there are few experimental studies on this topic. Here we quantified how nine ectomycorrhizal fungi in association with Pinus sylvestris seedlings affected Soil Aggregation and Soil water repellency (SWR) of a sandy loamy Soil. Water-stable aggregates (>0.25 mm diameter) increased by 6–12% when plants were associated with Laccaria bicolor, Laccaria laccata, Lactarius theiogalus, Paxillus involutus and Suillus bovinus. Mean weight diameter (MWD) of Soil aggregates also increased, primarily in the 2–4 mm diameter size class. However, Suillus granulatus increased water-stable aggregates but not MWD, conversely Rhizopogon roseolus and Suillus luteus increased MWD but not water-stable aggregates. We also found Lt. theiogalus, R. roseolus and S. luteus promoted SWR. Furthermore, hyphal length was weakly correlated with MWD (R = 0.27, P
M.v. López - One of the best experts on this subject based on the ideXlab platform.
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Tillage and cropping intensification effects on Soil Aggregation: Temporal dynamics and controlling factors under semiarid conditions
Geoderma, 2008Co-Authors: Jorge Álvaro-fuentes, J.l. Arrúe, R. Gracia, M.v. LópezAbstract:Abstract During decades, in semiarid agroecosystems of the Ebro valley, intensive Soil tillage and low crop residue input has led to a loss of Soil structure. Conservation tillage and cropping intensification can improve Soil structure in these areas. The objective of this study was to determine the influence of three different tillage systems (conventional tillage, CT; reduced tillage, RT; and no-tillage, NT) under two cropping systems (barley–fallow rotation, CF; and continuous barley, CC) on Soil Aggregation dynamics during two consecutive growing seasons (2003–2004 and 2004–2005). At the same time, the role that different Soil and climatic factors play on Soil Aggregation in these semiarid areas was studied. Soil samples were collected at the Soil surface (0–5 cm depth) from a long-term tillage experiment with a loamy Soil (Xerollic Calciorthid). Two Aggregation indexes were studied: dry aggregate size distribution and water aggregate stability from both air-dried and field-moist macroaggregates. A decrease in tillage intensity resulted in a higher mean size of dry aggregates and a greater water aggregate stability in both cropping systems particularly under NT. During the whole experiment, the dry aggregate size distribution (measured as the mean weight diameter, MWD) and the water stability of field-moist and air-dried Soil aggregates (WAS AD and WAS FM , respectively) were greater under NT than under RT and CT due to a higher Soil organic matter content under NT. Intensification of cropping system resulted in a greater water aggregate stability (both WAS AD and WAS FM ) but it did not have any effect in the MWD. Differences among tillage treatments were more pronounced under the CC system than under the CF rotation due to the lower Soil organic matter content and microbial biomass when long-fallowing was used. Variations in Soil Aggregation dynamics during the cropping season were mainly affected by crop growth and the associated activity of Soil microorganisms. These findings indicate that the use of alternative management practices as NT and CC are viable strategies to improve Soil Aggregation from semiarid Ebro valley.
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Tillage and cropping intensification effects on Soil Aggregation: Temporal dynamics and controlling factors under semiarid conditions
Geoderma, 2008Co-Authors: Jorge Álvaro-fuentes, J.l. Arrúe, R. Gracia, M.v. LópezAbstract:The definitive version is available at:\ud \ud http://www.sciencedirect.com/science/journal/00167061During decades, in semiarid agroecosystems of the Ebro valley, intensive Soil tillage and low crop residue input has led to a loss of Soil structure. Conservation tillage and cropping intensification can improve Soil structure in these areas. The objective of this study was to determine the influence of three different tillage systems (conventional tillage, CT; reduced tillage, RT; and no-tillage, NT) under two cropping systems (barley–fallow rotation, CF; and continuous barley, CC) on Soil Aggregation dynamics during two consecutive growing seasons (2003–2004 and 2004–2005). At the same time, the role that different Soil and climatic factors play on Soil Aggregation in these semiarid areas was studied. Soil samples were collected at the Soil surface (0–5 cm depth) from a long-term tillage experiment with a loamy Soil (Xerollic Calciorthid). Two Aggregation indexes were studied: dry aggregate size distribution and water aggregate stability from both air-dried and field-moist macroaggregates. A decrease in tillage intensity resulted in a higher mean size of dry aggregates and a greater water aggregate stability in both cropping systems particularly under NT. During the whole experiment, the dry aggregate size distribution (measured as the mean weight diameter, MWD) and the water stability of field-moist and air-dried Soil aggregates (WASAD and WASFM, respectively) were greater under NT than under RT and CT due to a higher Soil organic matter content under NT. Intensification of cropping system resulted in a greater water aggregate stability (both WASAD and WASFM) but it did not have any effect in the MWD. Differences among tillage treatments were more pronounced under the CC system than under the CF rotation due to the lower Soil organic matter content and microbial biomass when long-fallowing was used. Variations in Soil Aggregation dynamics during the cropping season were mainly affected by crop growth and the associated activity of Soil microorganisms. These findings indicate that the use of alternative management practices as NT and CC are viable strategies to improve Soil Aggregation from semiarid Ebro valley.This research was supported by the Comisión Interministerial de Ciencia y Tecnología of Spain (Grants AGL2001-2238-CO2-01, AGL2004-07763-C02-02 and AGL2007-66320-CO2-02/AGR) and the European Union (FEDER funds). The first author was awarded a FPI fellowship by the Spanish Ministry of Science and Education.Peer reviewe
