The Experts below are selected from a list of 312 Experts worldwide ranked by ideXlab platform
Tamara Münkemüller - One of the best experts on this subject based on the ideXlab platform.
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Effects of plant functional traits on Soil Stability: intraspecific variability matters
Plant and Soil, 2017Co-Authors: Hamada E Ali, Björn Reineking, Tamara MünkemüllerAbstract:Soil Stability is a key ecosystem function provided by agricultural landscapes. A multitude of influential factors such as Soil texture and plant community structure have been suggested, but few studies compare the relative importance of these factors for Soil Stability in the field. In addition, studies on effects of plant traits on Soil Stability have ignored intraspecific trait variability despite growing evidence of its importance for ecosystem functioning. Using path model analysis, we quantified the effect of plant functional traits (PFTs), abiotic Soil characteristics and vegetation characteristics on three Soil Stability measures in 30 field margins of an agriculture landscape of Korea. We compare models with and without intraspecific trait variability. Variance in Soil Stability was relatively well explained by our conceptual path model (81 % explained variance for Soil aggregate Stability, 50 % for penetration resistance and 35 % for Soil shear vane strength). The overall most influential variable was root density while vegetation cover and species richness was much less important. Accounting for intraspecific trait variability improved the goodness-of-fit of all path models but not the overall explained variance. However, intraspecific trait variability allowed identifying important direct and indirect effects of PFTs on Soil Stability that would have remained hidden otherwise. We have demonstrated that the consideration of intraspecific trait variability – even though measuring it could strongly limit achievable sample sizes – is essential for uncovering the substantial effect of plant functional community composition on a key ecosystem function, Soil Stability.
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Effects of plant functional traits on Soil Stability: intraspecific variability matters
Plant and Soil, 2017Co-Authors: Hamada Ali, Björn Reineking, Tamara MünkemüllerAbstract:Background and aims: Soil Stability is a key ecosystem function provided by agricultural landscapes. A multitude of influential factors such as Soil texture and plant community structure have been suggested, but few studies compare the relative importance of these factors for Soil Stability in the field. In addition, studies on effects of plant traits on Soil Stability have ignored intraspecific trait variability despite growing evidence of its importance for ecosystem functioning. Methods: Using path model analysis, we quantified the effect of plant functional traits (PFTs), abiotic Soil characteristics and vegetation characteristics on three Soil Stability measures in 30 field margins of an agriculture landscape of Korea. We compare models with and without intraspecific trait variability. Results: Variance in Soil Stability was relatively well explained by our conceptual path model (81 % explained variance for Soil aggregate Stability, 50 % for penetration resistance and 35 % for Soil shear vane strength). The overall most influential variable was root density while vegetation cover and species richness was much less important. Accounting for intraspecific trait variability improved the goodness-of-fit of all path models but not the overall explained variance. However, intraspecific trait variability allowed identifying important direct and indirect effects of PFTs on Soil Stability that would have remained hidden otherwise. Conclusion: We have demonstrated that the consideration of intraspecific trait variability – even though measuring it could strongly limit achievable sample sizes – is essential for uncovering the substantial effect of plant functional community composition on a key ecosystem function, Soil Stability.
Hamada Ali - One of the best experts on this subject based on the ideXlab platform.
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Effects of plant functional traits on Soil Stability: intraspecific variability matters
Plant and Soil, 2017Co-Authors: Hamada Ali, Björn Reineking, Tamara MünkemüllerAbstract:Background and aims: Soil Stability is a key ecosystem function provided by agricultural landscapes. A multitude of influential factors such as Soil texture and plant community structure have been suggested, but few studies compare the relative importance of these factors for Soil Stability in the field. In addition, studies on effects of plant traits on Soil Stability have ignored intraspecific trait variability despite growing evidence of its importance for ecosystem functioning. Methods: Using path model analysis, we quantified the effect of plant functional traits (PFTs), abiotic Soil characteristics and vegetation characteristics on three Soil Stability measures in 30 field margins of an agriculture landscape of Korea. We compare models with and without intraspecific trait variability. Results: Variance in Soil Stability was relatively well explained by our conceptual path model (81 % explained variance for Soil aggregate Stability, 50 % for penetration resistance and 35 % for Soil shear vane strength). The overall most influential variable was root density while vegetation cover and species richness was much less important. Accounting for intraspecific trait variability improved the goodness-of-fit of all path models but not the overall explained variance. However, intraspecific trait variability allowed identifying important direct and indirect effects of PFTs on Soil Stability that would have remained hidden otherwise. Conclusion: We have demonstrated that the consideration of intraspecific trait variability – even though measuring it could strongly limit achievable sample sizes – is essential for uncovering the substantial effect of plant functional community composition on a key ecosystem function, Soil Stability.
Björn Reineking - One of the best experts on this subject based on the ideXlab platform.
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Effects of plant functional traits on Soil Stability: intraspecific variability matters
Plant and Soil, 2017Co-Authors: Hamada E Ali, Björn Reineking, Tamara MünkemüllerAbstract:Soil Stability is a key ecosystem function provided by agricultural landscapes. A multitude of influential factors such as Soil texture and plant community structure have been suggested, but few studies compare the relative importance of these factors for Soil Stability in the field. In addition, studies on effects of plant traits on Soil Stability have ignored intraspecific trait variability despite growing evidence of its importance for ecosystem functioning. Using path model analysis, we quantified the effect of plant functional traits (PFTs), abiotic Soil characteristics and vegetation characteristics on three Soil Stability measures in 30 field margins of an agriculture landscape of Korea. We compare models with and without intraspecific trait variability. Variance in Soil Stability was relatively well explained by our conceptual path model (81 % explained variance for Soil aggregate Stability, 50 % for penetration resistance and 35 % for Soil shear vane strength). The overall most influential variable was root density while vegetation cover and species richness was much less important. Accounting for intraspecific trait variability improved the goodness-of-fit of all path models but not the overall explained variance. However, intraspecific trait variability allowed identifying important direct and indirect effects of PFTs on Soil Stability that would have remained hidden otherwise. We have demonstrated that the consideration of intraspecific trait variability – even though measuring it could strongly limit achievable sample sizes – is essential for uncovering the substantial effect of plant functional community composition on a key ecosystem function, Soil Stability.
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Effects of plant functional traits on Soil Stability: intraspecific variability matters
Plant and Soil, 2017Co-Authors: Hamada Ali, Björn Reineking, Tamara MünkemüllerAbstract:Background and aims: Soil Stability is a key ecosystem function provided by agricultural landscapes. A multitude of influential factors such as Soil texture and plant community structure have been suggested, but few studies compare the relative importance of these factors for Soil Stability in the field. In addition, studies on effects of plant traits on Soil Stability have ignored intraspecific trait variability despite growing evidence of its importance for ecosystem functioning. Methods: Using path model analysis, we quantified the effect of plant functional traits (PFTs), abiotic Soil characteristics and vegetation characteristics on three Soil Stability measures in 30 field margins of an agriculture landscape of Korea. We compare models with and without intraspecific trait variability. Results: Variance in Soil Stability was relatively well explained by our conceptual path model (81 % explained variance for Soil aggregate Stability, 50 % for penetration resistance and 35 % for Soil shear vane strength). The overall most influential variable was root density while vegetation cover and species richness was much less important. Accounting for intraspecific trait variability improved the goodness-of-fit of all path models but not the overall explained variance. However, intraspecific trait variability allowed identifying important direct and indirect effects of PFTs on Soil Stability that would have remained hidden otherwise. Conclusion: We have demonstrated that the consideration of intraspecific trait variability – even though measuring it could strongly limit achievable sample sizes – is essential for uncovering the substantial effect of plant functional community composition on a key ecosystem function, Soil Stability.
Louise Deschênes - One of the best experts on this subject based on the ideXlab platform.
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Effect of copper on Soil functional Stability measured by relative Soil Stability index (RSSI) based on two enzyme activities.
Chemosphere, 2008Co-Authors: Marylène Dussault, Valérie Bécaert, Matthieu François, Sébastien Sauvé, Louise DeschênesAbstract:Abstract Copper can affect essential processes in Soils, often for long periods. Enzyme activity is considered a sensitive indicator to evaluate Soil health and the potential toxic impact of a Soil contaminant. Nevertheless, there is heterogeneity in the responses from enzyme activity assays because of the influence of pH and other physicochemical parameters on both enzyme activity and metal speciation. This leads to complications when comparing Soils and limits the validity of the results. To overcome these problems, this paper evaluates resistance and recovery, quantified by using a relative Soil Stability index (RSSI), of the β-glucosidase and protease activities towards an additional heat disturbance (17 h at 60 °C) in Soils where Soil organic matter, pH and Cu content were modified in a factorial setup. Chemical analyses (dissolved Cu, pCu 2+ , dissolved organic carbon, pH) were performed both before the heat-perturbation and after the enzyme activity monitoring period. Results show that Soil pH did not interfere with the RSSI scores of both enzymes. β-glucosidase RSSI scores were scarcely affected by copper, making it inappropriate for evaluating copper-induced stress to Soils. Protease activity shows stimulations of up to 2.5 times the activity of the unperturbed control in uncontaminated samples only. Thus, the protease RSSI score seems a good indicator for Soil health relative to copper contamination given that all samples were affected by the presence of copper and high correlations were observed between RSSI scores and the different copper forms.
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Effect of 2,4-D contamination on Soil functional Stability evaluated using the relative Soil Stability index (RSSI)
Chemosphere, 2006Co-Authors: Valérie Bécaert, Réjean Samson, Louise DeschênesAbstract:Abstract Soil functional Stability is the capacity of Soil functions to resist and recover from an environmental perturbation and can be used to evaluate Soil health. It can be influenced by the presence of xenobiotics such as herbicides. The impact of a fresh 2,4-D contamination (36 mg kg −1 dry Soil) on Soil functional Stability was evaluated by comparing the capacity of Soil enzyme activities to resist and recover from a heat perturbation for both a clean and 2,4-D-contaminated Soil. The functional stabilities of the Soils (uniform sands, pH 6.9, 7% (w/w) organic matter) were calculated using the relative Soil Stability index (RSSI). The RSSI scores indicate the proportion of potential enzyme activity the Soil retains after a perturbation compared to the potential activity of an unperturbed Soil. Six extra-cellular enzyme activities (acid and alkaline phosphatases, arylsulfatase, urease, protease and β-glucosidase) were monitored in Soil microcosms during a 15-day period. During this period, a 60 °C heat perturbation was applied to the Soil for 24 h. The activities of arylsulfatase and protease were found to be the most stable following heat perturbation obtaining the highest RSSI scores (87% and 77%, respectively). Urease activity showed the lowest RSSI score (38%). Although all enzyme activities were inhibited by the presence of 2,4-D, the RSSI results indicated that contamination lowered the Stability of only three enzyme activities (arylsulfatase, β-glucosidase and urease). The RSSI adequately described resistance, recovery and recovery rate parameters and enabled differentiation between functional stabilities of clean and contaminated Soil and between different Soil types.
Matthias C. Rillig - One of the best experts on this subject based on the ideXlab platform.
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Visualizing the dynamics of Soil aggregation as affected by arbuscular mycorrhizal fungi
The ISME Journal, 2019Co-Authors: E. K. Morris, D. J. P. Morris, Sophie Charlotte Gleber, MANFRED BIGALKE, S Vogt, Wolfgang Wilcke, Matthias C. RilligAbstract:Stable Soils provide valuable ecosystem services and mechanical Soil Stability is enhanced by the presence of arbuscular mycorrhizal fungi (AMF). Soil aggregation, which is the major driver of mechanical Soil Stability, is often treated as a static phenomenon, even though aggregate turnover is continually ongoing. In fact, some breakdown of macroaggregates is necessary to allow new aggregate formation and inclusion of new organic matter into microaggregates. We determined how aggregate turnover times were affected by AMF by tracking movement of rare earth elements (REE), applied as their immobile oxides, between aggregate size classes, and using X-ray fluorescence microscopy to spatially localize REEs in a sample of aggregates. Here we show that AMF increased large macroaggregate formation and slowed down disintegration of large and small macroaggregates. Microaggregate turnover was increased in the presence of AMF. Internal aggregate organization suggested that although formation of microaggregates by accretion of Soil to particulate organic matter is common, it is not the only mechanism in operation.
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Untangling the biological contributions to Soil Stability in semiarid shrublands
Ecological Applications, 2009Co-Authors: V. Bala Chaudhary, Matthias C. Rillig, Matthew A. Bowker, Thomas E. O'dell, James B. Grace, Andrea Redman, Nancy Collins JohnsonAbstract:Communities of plants, biological Soil crusts (BSCs), and arbuscular mycorrhizal (AM) fungi are known to influence Soil Stability individually, but their relative contributions, interactions, and combined effects are not well understood, particularly in arid and semiarid ecosystems. In a landscape-scale field study we quantified plant, BSC, and AM fungal communities at 216 locations along a gradient of Soil Stability levels in southern Utah, USA. We used multivariate modeling to examine the relative influences of plants, BSCs, and AM fungi on surface and subsurface Stability in a semiarid shrubland landscape. Models were found to be congruent with the data and explained 35% of the variation in surface Stability and 54% of the variation in subsurface Stability. The results support several tentative conclusions. While BSCs, plants, and AM fungi all contribute to surface Stability, only plants and AM fungi contribute to subsurface Stability. In both surface and subsurface models, the strongest contributions to Soil Stability are made by biological components of the system. Biological Soil crust cover was found to have the strongest direct effect on surface Soil Stability (0.60; controlling for other factors). Surprisingly, AM fungi appeared to influence surface Soil Stability (0.37), even though they are not generally considered to exist in the top few millimeters of the Soil. In the subsurface model, plant cover appeared to have the strongest direct influence on Soil Stability (0.42); in both models, results indicate that plant cover influences Soil Stability both directly (controlling for other factors) and indirectly through influences on other organisms. Soil organic matter was not found to have a direct contribution to surface or subsurface Stability in this system. The relative influence of AM fungi on Soil Stability in these semiarid shrublands was similar to that reported for a mesic tallgrass prairie. Estimates of effects that BSCs, plants, and AM fungi have on Soil Stability in these models are used to suggest the relative amounts of resources that erosion control practitioners should devote to promoting these communities. This study highlights the need for system approaches in combating erosion, Soil degradation, and arid-land desertification.
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Disentangling the impact of AM fungi versus roots on Soil structure and water transport
Plant and Soil, 2008Co-Authors: Paul D. Hallett, Matthias C. Rillig, Debbie S. Feeney, A. Glyn Bengough, Charles M. Scrimgeour, Iain M. YoungAbstract:The relative importance of roots and AM-fungi on Soil physical processes was investigated by controlling the presence of roots and AM fungi in pot experiments using a mycorrhiza-defective tomato mutant and a wild-type tomato (Solanum lycopersicum L.). Root-Zone and Bulk Soil sections were established by splitting pots into two lengthwise halves using a nylon mesh that contained roots whilst allowing the free movement of fungal hyphae. Post-incubation microbial populations and fungal biomass were measured and related to Soil Stability, pore structure and water repellency. Unplanted controls consistently had the least fungal biomass, fatty acids, water-stable aggregates (WSA) and water repellency. Wild-type-planted treatments had significantly more WSA than mycorrhiza-defective treatments (P < 0.01). Fluctuations in water content induced by transpiration caused significant changes in Soil pore structure, measured using high-resolution X-Ray computer tomography. Porosity and mean pore size increased in Soil aggregates from planted treatments, which had larger more heterogeneous pores than those in the unplanted Soils. AM fungi accentuated Soil Stability. However, changes were not linked to repellency and fungal biomass. The presence of plants, regardless of AM fungi, appears to have the greatest impact on increasing Soil Stability.