Soils

Elsevier, Soil Biology and Biochemistry, Volume 149, October 2020
Fire is an ecological disturbance that alters soil microbiomes and the functions they mediate in terrestrial ecosystems. Soil microbial diversity in Mediterranean Basin ecosystems shows resilience to fire following the restoration of plant-soil feedbacks. We hypothesised that microbial functions related to organic matter decomposition and nutrient cycling might show similar patterns of recovery.
The biochemical effects of trees may significantly influence local pedogenesis as well as pedocomplexity, biodiversity and forest dynamics on both stand and landscape scales. One such effect is the decay of tree trunks, which is driven by organisms, and especially by the microbiome. Decomposition modifies soil formation, which due to the existence of many feedbacks affects the composition of the decomposer community.
Urbanisation involves major changes in environmental conditions such as light, temperature, humidity and noise levels, but the effect of urbanisation on soil conditions and soil biodiversity has received less attention. The reported effects on species richness across a rural to urban landscapes are not unequivocal. Positive, negative and neutral effects have been found, but what is causing this ambiguity in the relationship between species richness and urbanisation is poorly understood.
Non-target effects of deliberately released organisms into a new environment are of great concern due to their potential impact on the biodiversity and functioning of ecosystems. Whereas these studies often focus on invasive species of macro-organisms, the use of microbial inoculants is often expected to have specific effects on particular functions but negligible overall effects on resident microbial communities. Here, we posit that such introductions often impact native microbial communities, which might influence ecosystem processes.
Non-ribosomal peptides (NRPs) and polyketides (PKs) are among the most profuse families of secondary metabolites (SM) produced by bacteria. These compounds are believed to play an important ecological role in microbe-microbe and microbe-plant interactions in soil and roots microbiomes. Over the years, screening of NRPs and PKs in soil bacteria has resulted in high rates of rediscovery, mainly due to challenges associated with bacterial isolation.
Soil organic matter (OM) stratification and macro and micro fauna are both good indicators for the evaluation of soil ecological functioning, which is interrelated with nutrient cycles. To the best of the authors’ knowledge, responses of the degree of OM stratification with soil depth expressed as a ratio, and belowground biota to forest degradation and land cover changes have received little attention, particularly in northern Iran.
There is a wide array of biomass utilisation pathways to mitigate greenhouse gas emissions. The characteristic of biomass, the demand for products, and the local constraints determine the sustainability of utilisation. Generic principles and criteria can be applied to the analysis of specific instances. This work develops a decision-making tool for determining the most sustainable use of biomass for carbon management. The mathematical principles are based on break-even analysis and are visualised in the form of a graphical display for transparent communication of results to decision-makers.
The artificial drainage of heavy textured gley soils is prevalent on pasture. Drainage of a soil profile reduces the water filled pore space (WFPS) in the upper soil horizons with consequences for N2 and N2O emissions, the fate of nitrogen (N), transformational processes and microbial and bacterial communities. The present intact soil column study with isotopically enriched fertiliser investigates all these aspects simultaneously under two WFPS treatments (80% (HS) and 55% (LS) saturation).
Elsevier, Soil Biology and Biochemistry, Volume 143, April 2020
Improving rice yield potential is crucial for global food security. Taoyuan, China, is famous worldwide as a special ecosite for ultrahigh rice yield. Climatological factors affecting this phenomenon have been identified, but the potential molecular processes and environmental mechanisms promoting ultrahigh yield remain mysteries.
Soil contamination by potentially toxic elements (PTEs) has led to adverse environmental impacts. In this review, we discussed remediation of PTEs contaminated soils through immobilization techniques using different soil amendments with respect to type of element, soil, and amendment, immobilization efficiency, underlying mechanisms, and field applicability. Soil amendments such as manure, compost, biochar, clay minerals, phosphate compounds, coal fly ash, and liming materials are widely used as immobilizing agents for PTEs.

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