Bacterial community dissimilarity in soils is driven by long‐term land‐use practices

Abstract

Land‐use practices impact soil microbial functionality and biodiversity, with reports suggesting that anthropogenic activities potentially result in reduced microbial functions and loss of species. The objective of this study was to assess the effect of long‐term (>50 yr) land use (natural forest and grassland, and agricultural land) on soil bacterial community structure. A high‐throughput sequencing‐by‐synthesis approach of the 16S rRNA gene was used to study bacterial community and predicted functional profiles of Alfisols, as affected by variables including land‐use (forest, grass, agricultural) and soil/crop management (rotation and tillage) in long‐term experimental plots in Hoytville, OH. The distribution of the abundant phyla was different across samples. No‐till soils showed higher diversity indices than the plow‐till (PT) soils. Ordinations across locations suggested that no‐till soils had distinctly different community structure compared with plow‐till soils, while crop rotation within the no‐till plot had highest number of taxa. Overall land use (forest, grass, agronomic treatment) and tillage (within agricultural soils) were found to be significant when evaluating bacterial community dissimilarity. Predictive functional profiles showed that the forest soil had greatest proportion of PICRUSt‐assignable gene functions followed by the no‐till and grassland soils whereas plow‐till soils had the lowest predicted gene abundances across all samples. The results provide a view of soil bacterial diversity and predictive functional capacity in long‐term land‐use and soil/crop management practices, with a potential to inform future experiments to increase our understanding of long‐term impacts of land use on microbial community structure and function.

Metagenomic Analyses of Plant Growth-Promoting and Carbon-Cycling Genes in Maize Rhizosphere Soils with Distinct Land-Use and Management Histories

“…This result is also consistent with the amounts of N-NO 3 and N-NH 4 found in the soils, as N in the form of nitrate (NO 3 ) increases the pH in the rhizosphere, while N in ammonium (NH 4 ) results in the acidification of the rhizosphere [ 68 ]. On the other hand, Sengupta et al [ 69 ] reported lower pH in plow-till soils and higher pH in no-till soils, in line with the results of this study. Furthermore, the canonical correspondence analysis (CCA) showed that N-NO 3 , with a significance level of 0.05, contributed the most (31%) to the differences observed in the diversity and abundance of carbon-cycling and plant growth-promoting genes in the samples ( Figure 7 and Table S4 ).…”

Spatial variation of soil bacteria communities and its alpha diversity as a potential bioindicator of land degradation

“…Conversely, the findings of this analysis confirmed a distinctly different matter where the Acidobacteria relative abundance was found to be higher in areas with elevated soil pH (PI and RS). The findings of this study were also similar to those stated by Sengupta et al (2020) that several Acidobacteria subgroups did not present in soils with low pH caused related to broad metabolic and physiological adaptations. Except for Proteobacteria and Acidobacteria, the relative abundance of Actinobacteria exhibited a significant difference in unmanaged soil (RS) and was lower than the abundance in managed soils in this study.…”

“…In line with Sengupta et al (2020), plowing activities affected low residue input in the soils, decreasing food sources for bacterial growth demands. Actinobacteria are a community of bacteria that play a crucial part in soil litter decomposition (Kopecky et al, 2011), induce plant growth promoters, biogeochemical nutrient cycles, increase abundance of nutrients (Bhatti et al, 2017;Zhang et al, 2019).…”

“…The soil bacteria are the fundamental pillar of the biosphere and are accountable for the stability of various essential processes in the ecosystem (Hendershot et al, 2017;Liu et al, 2020). Soil bacteria contribute to fundamental ecological processes such as decomposition, greenhouse gas regulation, xenobiotic compound breakdown, biogeochemical nutrient cycles, and plant growth (Sengupta et al, 2020). Soil bacteria are organisms that are susceptible to changing environmental conditions.…”

Structural and functional microbial community response to short-term impact of switching between tillage and no-tillage at soil aggregate level

“…NT combined with crop rotation constitute a conservative and sustainable way of doing agriculture, and the conversion from conventional tillage to no-till has led many benefits like avoid soil degradation, increase SOM, aggregation and enhance soil health (Derpsch et al, 2010) and also show significant differences at the prokaryotic community level (Sengupta and Dick, 2015;Sengupta et al, 2020). However, the transition to a new tillage systems is not immediate and many studies had explored this changes at SOM containing (Alvarez & Steinbach, 2009;a -Zorita et al, 2002;Du et al, 2014;Franzluebbers & Arshad, 1996;Martinez et al, 2020;West & Post, 2002), at microbial community's composition analy ed by PLFA (Feng et al, 2003;Jiang et al, 2011b;Simmons & Coleman, 2008;Wortmann et al, 2008) and at functional level through the use of enzymes activities (Gabbarini, in revision;Pandey et al, 2014).…”