Bacteria (microorganisms)

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.
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.
Climate change and population growth generates a decrease in water availability around the world which can compromise the maintenance of sustainable agriculture. Thus, treated wastewater (TWW) became an alternative to minimize water shortage. However, this may indirectly affect the soil's microbial properties. In this study different soils irrigated for 0, 1, 8 and 20 years with TWW were sampled and from the east central region of Tunisia.
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.
Although the effects of nitrogen (N) fertilization on soil microflora have been well studied, the effects should be verified across soil types and N-added levels. To understand the impacts of N fertilization on shifts in soil biological traits and bacterial communities and to further explore the coupling mediation of these parameters with respect to crop yields, we sampled soils from three experimental sites (each site received three levels of N fertilization (0, 168 and 312 kg N ha−1)) that share the same climatic conditions but have different soil types (clay, alluvial and sandy soils).
This study assessed the carbon (C) budget and the C stocks in major compartments of the soil food web (bacteria, fungi, protists, nematodes, meso- and macrofauna) in an arable field with/without litter addition. The C stocks in the food web were more than three times higher in topsoil (0–10 cm) compared to subsoil (>40 cm). Microorganisms contained over 95% of food web C, with similar contributions of bacteria and fungi in topsoil. Litter addition did not alter C pools of soil biota after one growing season, except for the increase of fungi and fungal feeding nematodes in the topsoil.
As emerging contaminants, antibiotic resistance genes (ARGs) have become a public concern. This study aimed to investigate the occurrence and diversity of ARGs, and variation in the composition of bacterial communities in source water, drinking water treatment plants, and tap water in the Pearl River Delta region, South China. Various ARGs were present in the different types of water. Among the 27 target ARGs, floR and sul1 dominated in source water from three large rivers in the region.
Over the last two decades, there has been growing interest on the effects of agricultural practices on soil biology in Europe. As soil biota are known to fluctuate throughout the season and as agro-environmental conditions may influence the effect of agricultural practices on soil organisms, conclusions cannot be drawn from a single study. Therefore, integrating the results of many studies in order to identify general trends is required. The main objective of this study was to investigate how soil biota are affected by repeated applications of organic amendments (i.e.