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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. [...]

Results of a recent multiyear experiment conducted on an agricultural plot that was recently converted from boreal forest (Labrador, Canada) suggested that NPK fertilizers contributed to better crop establishment and higher yield but only when it was applied along with biochar. The failure of fertilizer only treatments to allow crop establishment and desirable growth and yield could be related to the deficiency of one or more micronutrients. Consequently, a missing element trial with a number of micronutrients (Mn, Cu, Zn, and Mo) was initiated on the same soil to investigate whether biochar can facilitate the availability of one or more of these micronutrients, contributing to crop growth and yields. Results show that the incorporation of chemical fertilizers with biochar produced significantly higher yields than in the absence of biochar. Furthermore, in the absence of biochar, the addition of micronutrients (i.e., Mn, Cu, Zn, and Mo) did not significantly increase yield. On the other hand, among the treatments that included biochar, the absence of a micronutrient (i.e., only three of the four micronutrients included) had either no effect (e.g., absence of Mn or Zn) or was associated with the increased yields (i.e., absence of Cu or Mo). Thus, it is proposed that while all tested micronutrients were present in the podzolic soil, with Cu and Mo possibly oversupplied, co-application with biochar enhanced both macronutrient and micronutrient utilization by plants. The data on the availability of micronutrients in the soil, their concentration in plants, and total uptake also support this conclusion. Thus, biochar facilitates the plant uptake of both naturally occurring and added micronutrients, and associated crop productivity, in a podzolic soil typical for lands converted from forest to agricultural use in the boreal ecoregion of Labrador. These results also challenge the view that micronutrients must always be added to Podzols to achieve maximum productivity; biochar-mediated micronutrient plant uptake deserves consideration when managing Podzols.

Carbon cycling in boreal regions is controlled naturally by fire disturbance, climate, hydrology, snowmelt, soil heterogeneity, acidity, low nitrogen and phosphorus availability, mycorrhizal distribution, plant cover, and cryoturbation/permafrost at the northern edge. It is primarily altered by human management via and following land clearance. Each factor interacts with others in complex ways, creating a system characterized by high carbon storage and shaped by natural and anthropogenic disturbance. This paper examines boreal research to answer the question: 'what are the primary factors controlling boreal carbon cycling?' Though climate change threatens boreal systems, they may yet be resilient given many natural feedback loops that resist massive carbon loss. Perhaps the greatest danger is land conversion, which causes permanent losses and drastic alteration of certain carbon pools. Accordingly, it might be argued that it would be overall better to implement policies that keep these lands as forests, including managed forests, rather than convert to agriculture. Conversely, farming of marginal boreal soils might be managed to enhance carbon storage while satisfying local food security needs. However, the impact of agriculture on soil carbon storage is yet to be effectively quantified and initial results offer inconsistent assessments, reflected in the as‐yet natural sciences data‐scarce policy development. Research targeting long‐term carbon cycling, land conversion practices, agroforestry, and communication between boreal scientists and other groups (climate scientists, policymakers, public, and farmers) must be addressed through creation of long‐term experiments. [ABSTRACT FROM AUTHOR]

Recovery of soil health offers insights into the mechanisms underpinning the stability of remediated ecosystems. Indirect assessment of enzymatic activity potential using substrate induced respiration (SIR), is commonly used to evaluate changes in soil microbial activity profiles, with their links to environmental and management factors. In this study, community level physiological profiling (CLPP) was employed to assess the impact of time on surface coal mine soil remediation. When compared with an adjoining control site, analysis of CLPP parameters offer useful insights and prospective tools for assessing soil health, following mining and remediation activities. [ABSTRACT FROM AUTHOR]

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 [...]