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Context. Although both plant cover and mulch are considered for erosion control in arid and semi-arid regions, they have divergent impacts on soil ecology. Aim. We examined the effects of orchard floor management practices on the density and diversity of soil free-living nematode communities and relevant soil abiotic properties. Methods. Soils were sampled in winter in a citrus orchard in the Sharon region of Israel from plots that for 6 years had been under (1) annual native species; or (2) Avena sativa and Vicia villosa, planted between tree rows; or (3) woodchip mulching along tree rows. There were two control sites: (4) bare soil between tree rows and (5) bare soil along the tree rows (both common practice). Key results. Nematode communities and their trophic diversity were significantly impacted by floor management. Significant increases in soil moisture under plant cover, and higher organic matter and water-holding capacity for all covered orchard floors could be related to nematode changes. Shifts in nematode feeding group structure suggest a shift in the type and availability of soil carbon pools. Conclusions. There was a strong association between orchard floor management and soil free-living nematode communities, indicating a shift in the soil food-web structure and functionality. Bare soil harboured fewer nematodes, but more complex communities dominated by persisters, while seeded plant cover had a greater nematode abundance dominated by coloniser communities, indicating increased availability of resources. Implications. Results reveal the importance of integrating biological information in performance index determinations for improving soil management decisions, suggesting these relationships as sensitive bio-indicators of soil health. Keywords: cover crops, functional diversity, mediterranean, mulching, nematodes, orchard, soil degradation, soil ecology., Introduction Any agricultural practice affects the functioning of soil biota (Dunn et al. 2021). This needs to be taken into consideration when contemplating a shift from conventional, intensive agriculture, characterised [...]

Conventional, sustainable or organic farming practices are assumed to have distinct effects on soil fertility and health. This is often supported by arguments linking management and resulting soil parameters to crop yield and produce quality. Soil microbial communities are sensitive to management practices that alter soil water fluxes and the pools and fluxes of nutrients. These effects might be accentuated in arid or semiarid agriculture. Conversion to vineyard use, under Mediterranean conditions, and the subsequent application of different management types creates the conditions for divergent soil microbial communities. An off-season survey of variably managed vineyards located in a Mediterranean climate showed that both organic and conventional vineyard management had the most distinct impact on soil abiotic parameters, and on the bacterial and fungal communities; both organic and sustainable management enhanced soil organic carbon, water holding capacity and nitrogen availability. The sustainable management led to soil microbial communities most similar to the natural conditions. Fungal diversity was better than bacterial diversity at discriminating between soils under different management types. Classes of the dominant Ascomycota phylum had best discriminating power; Mucoromycota declined significantly after conversion to vineyard use and was a key taxonomic indicator for such conversion. Regarding bacterial communities, a focus on functional categories, e.g. nitrogen-fixing taxa, may be more informative than total diversity assessments. Keywords: arbuscular mycorrhizae, land-use conversion, Mediterranean, microbial diversity, nitrogen-fixing bacteria, organic, soil fertility, vineyard., Introduction Demands from consumers and policy makers for more sustainable agriculture led to the emergence of numerous sustainable vineyard programs, which are then reflected in wine labels (Viers et al. [...]

Abstract: Land application of organic wastes can lead to contamination of ground- and surface waters. The pathway taken by particulate contaminants, such as microorganisms, is entirely dependent on the partitioning [...]

We evaluated the impact of the manure type used in soil--manure mixtures on the detection of culturable E. coli as tested in water quality monitoring. A series of incubation experiments, lasting up to 200 d, allowed evaluation of the potential impact of manure x soil interactions on the augmentation of culturable E. coil Two soil types (sandy loam and a silt loam), two manure types (liquid swine manure and solid beef cattle manure), and three temperature levels (4, 12, and 20[degrees]C) were investigated. The significance of the presence of competing microorganisms was estimated by comparing results from manure mixtures with sterile and nonsterile soils. Water content in the soil-manure mixtures was maintained close to field capacity to eliminate the specific impact of water availability. We found that culturability of the indicator organism, E. coil changed with time and was dependent on the type of manure used and its interaction with soil. Escherichia coli could be cultured fur a longer time from soils with liquid manure additions. Whereas E. coli numbers were initially higher from soils treated with solid beef cattle manure, their numbers decreased more rapidly and the duration of their apparent survival was shorter. Resilience of culturable E. coli was independent of their initial numbers in manure.

A hypothetical study was conducted to prove that addition of biosolid nutrients to soil would enhance recovery of Escherichia coli naturally found in soil. The experimental effect was most marked for the deeper soil layers, with increases of about 2.6 orders of magnitude in E. coli most probable number.