Search results for "soil"

Biogenic Fenton process - A possible mechanism for the mineralization of organic carbon in fresh waters.

2020

To explore the mechanisms that mineralize poorly bioavailable natural organic carbon (OC), we measured the mineralization of OC in two lake waters over long-term experiments (up to 623 days) at different pH and iron (Fe) levels. Both the microbial and photochemical mineralization of OC was higher at pH acidified to 4 than at the ambient pH 5 or an elevated pH 6. During 244 days, microbes mineralized up to 60% of OC in the 10-mu m filtrates of lake water and more than 27% in the 1-mu m filtrates indicating that large-sized microbes/grazers enhance the mineralization of OC. A reactivity continuum model indicated that the acidification stimulated the microbial mineralization of OC especially i…

Diuron mobility through vineyard soils contaminated with copper

2005

International audience; The herbicide diuron is frequently applied to vineyard soils in Burgundy, along with repeated treatments with Bordeaux mixture (a blend of copper sulfate and calcium hydroxide) that result in elevated copper concentrations. Cu could in principle affect the fate and transport of diuron or its metabolites in the soil either directly by complexation or indirectly by altering the populations or activity of microbes involved in their degradation. To assess the effect of high Cu concentrations on diuron transport, an experiment was designed with ten undisturbed columns of calcareous and acidic soils contaminated with 17–509 mg kg−1 total Cu (field-applied). Grass was plant…

Global monitoring of soil animal communities using a common methodology.

2022

Here we introduce the Soil BON Foodweb Team, a cross-continental collaborative network that aims to monitor soil animal communities and food webs using consistent methodology at a global scale. Soil animals support vital soil processes via soil structure modification, consumption of dead organic matter, and interactions with microbial and plant communities. Soil animal effects on ecosystem functions have been demonstrated by correlative analyses as well as in laboratory and field experiments, but these studies typically focus on selected animal groups or species at one or few sites with limited variation in environmental conditions. The lack of comprehensive harmonised large-scale soil anim…

Plant-soil interactions in cold climate

2013

Natural enemies emerging in cereal fields in spring may contribute to biological control

2022

1.Biological pest control is known to depend on landscape heterogeneity. However, such relationship shows irregular pattern and seems influenced by local farming practices and natural enemies that overwinter within crop fields. The objective of this study was to assess the contribution of emerging natural enemies in spring to biological control, and their response to the interaction between landscape heterogeneity and farming intensity. 2.We monitored the overwintering insect community using emergence traps and measured the local potential pest predation using prey cards in 30 cereal fields, in spring in France. Study fields were selected along a landscape heterogeneity gradient and farming…

Using static and dynamic indicators to evaluate soil physical quality in a Sicilian area

2016

Both capacitive indicators derived from the water retention curve and dynamic measurements of the flow-weighted mean pore radius, R0, were used to assess the soil physical quality of two agricultural areas (cropland and olive orchard) and two natural areas (grassland and managed woodlot plantation) potentially subject to soil degradation. The overall idea of the study was to investigate whether a dynamic indicator quantitatively derived from hydraulic conductivity measurements could be used to supplement the traditionally applied capacitive indicators retrieved from water retention measurements. According to the available criteria, only the surface layer of the cropland site showed optimal …

Sedimentation and tropical vegetation changes in Southern Benin (West Africa), carbon-13 tracing of organic matter dynamics and fluctuations of the s…

2007

12 pages; International audience

Global diversity and geography of soil fungi

2014

Fungi play integral roles in soil nutrient cycling, but the determinants of fungal diversity and biogeographic patterns of key functional groups remain poorly understood. By using pyrosequencing data from hundreds of globally distributed soil samples, we demonstrated fungal diversity that expands upon the taxonomic and molecular diversity recorded so far. Except for ectomycorrhizal symbionts, fungal functional group richness was unrelated to plant diversity and plant-to-fungus richness ratio declined exponentially towards the poles. Climatic factors, followed by edaphic and spatial variables, constituted the best predictors of fungal richness and community composition at the global scale. F…

Influence of cultivation techniques and use of two nutritive solution with different electrical conductivity on the production and quality of cucumbe…

2009

The most suitable techniques and use of F1 hybrids enable greenhouse production to achieve high yields, with crops all year round. In Sicily, greenhouse production of cucumber is for fresh use (slicers), producing large fruit. The cultivation technique most suited to greenhouses is the vertical single stem. However, an innovative technique being proposed is of cultivation on a trellis, eliminating lower branches, and training the remaining branches upwards (vertical shoot positioning, VSP). Cucumbers in the south of Italy are grown as the main crop or as a catch crop between 2 main crops. The crop should be rotated on the same soil only after 3-4 years with another crop, unless the land is …

Actual provision as an alternative criterion to improve the efficiency of payments for ecosystem services for C sequestration in semiarid vineyards

2016

The aim of this paper is to evaluate the efficiency of the PES scheme actually used in the Sicilian rural development program, based on an egalitarian criterion, and proposing an alternative scheme in order to guarantee a greater equity and fairness of premium distribution in relation to soil carbon (C) sequestration potential. We, first, assessed the ecosystem services (ES) provided by agri-environmental measures (AEM) in terms of SOC stock increase in Sicilian vineyards. Based on these data we evaluated the efficiency of agro-environmental payments according to an egalitarian criterion and simulated the effects of the actual provision criterion adoption. Results showed that the adoption o…