Changes in Soil Microbial Community Structure in a Tallgrass Prairie Chronosequence

Abstract

Understanding the mechanisms that regulate microbial community structure and activity is important if we Increasing the abundance of fungi relative to bacteria should favor are to manage C and N stocks in soils. In general, fungi C accrual, because fungi use C more efficiently, and are composed of more recalcitrant C compounds. We examined changes in soil become more important determinates of decomposition microbial community structure following cessation of tillage-based in soils returned to a more natural state (e.g., Bardgett agriculture and through subsequent succession in a C-accruing tall

Microbial Community Variation and Its Relationship With Nitrogen Mineralization in Historically Altered Forests

“…Previous work examining the influence of past management on soil microbial communities has focused on grassland communities (Steenwerth et al 2003, Allison et al 2005, where vegetation recovery and organic-matter accumulation may proceed slowly. In southern Appalachian cove-hardwood communities, conditions are highly conducive to vegetation reestablishment and nutrient re-accumulation following disturbance.…”

“…Rather, the observed patterns are consistent with the results of previous work investigating the short-term effects of land management on soil microbial communities. Cultivation and tillage substantially disrupt the soil by breaking up soil aggregates, increasing soil compaction, exposing previously protected organic matter, and mixing soil horizons (Beare 1997, Allison et al 2005. These changes cause significant declines in microbial biomass, reducing the abundance of fungi, aerobic microorganisms, and facultative anaerobes, while increasing the relative abundance of GmϪ bacteria (Doran 1980, Beare 1997.…”

Bacterial and Fungal Contributions to Carbon Sequestration in Agroecosystems

“…For these reasons, we argue that qCO 2 is not an appropriate measure of microbial efficiency and suggest that new approaches for measuring MGE in soils need to be developed. Based on the assumption of higher fungal MGE, it has been hypothesized that more MOM will be formed in less disturbed systems (such as no-tillage soils and abandoned agricultural soils) where fungi represent a higher proportion of the total microbial biomass (Beare et al, 1992;Holland and Coleman, 1987;Allison et al, 2005). This hypothesis that fungi have higher MGE has been in the literature for decades, yet there is little supporting evidence, and rigorous in situ testing is required.…”

“…These fungal-dominated agroecosystems require fewer inputs to sustain organic matter decomposition and nutrient cycling, that is, these systems show greater self-regulation (Bardgett and McAlister, 1999;Yeates et al, 1997). However, Allison et al (2005) concluded that an improved metabolic efficiency due to increased relative abundance of arbuscular mycorrhizal fungi (AMF) and saprophytic fungi does not promote the stabilization of C on cessation of tillage-based agriculture.…”

Inverse modeling of hydrologic parameters using surface flux and runoff observations in the Community Land Model

“…These sites/basins are chosen based on previous sensitivity analyses over a larger set of flux tower sites and MOPEX basins (Hou et al, 2012;Huang et al, 2013) that demonstrated the feasibility and necessity of parameter calibration at those locations and to provide representative and contrasting climate and environmental conditions within the United States for more robust conclusions. US-ARM is located in Oklahoma and is covered by croplands (Allison et al, 2005;Baer et al, 2002;Fischer et al, 2007;Riley et al, 2009;Suyker and Verma, 2009). US-MOz is located in Missouri and is covered by deciduous broadleaf (Gu et al, 2012(Gu et al, , 2006.…”