The US National Mall Microbiome: A Census of Rhizosphere Bacteria Inhabiting Landscape Turf

Abstract

A groecosystems are increasingly at risk due to the movement of nonindigenous microorganisms into new environments (Waage and Mumford, 2008). More than half of all documented plant pathogen invasions are directly attributable to humanmediated transfer of nonindigenous microorganisms (Anderson et al., 2004). It is generally accepted that heightened levels of microbial invasions in recent years are correlated with intensified globalization, specifically due to growing levels of world trade in agricultural commodities, tourism, transportation, and travel (Waage and Mumford, 2008). In turfgrass ecosystems, the introduction of nonindigenous microorganisms occurs through numerous human-mediated processes, including foot traffic and recreational use, machinery and irrigation systems, and the use of commercially sourced materials such as sand, organic matter, sod, etc.

Urban Grassland Management Implications for Soil C and N Dynamics: A Microbial Perspective

“…Schedonorus phoenix (Scop.)] and P. pratensis L., the soil microbiome was compared pre-and postrenovation with the originating sod farm (Crouch et al, 2017). Bacterial 16S rRNA sequencing revealed that across all four lawns in the study, the Gram-negative, Proteobacteria phylum was 52.2-58.6% of the observed sequences, of which the genus Rhodoplanes was widely abundant (26.4-37.3%).…”

“…Increased SOM if turf species are deeper rooting (Qian et al, 2010); specific turfgrass species differences in soil C, N, and SOM accumulation (Law et al, 2017); increased soil N retention and turf productivity with diverse turf systems (Thompson and Kao-Kniffin, 2016); the soil microbiome across different urban grasslands in the Mid-Atlantic region pre-and post-construction were more similar than different, but were enriched with copiotrophic bacteria (Crouch et al, 2017) Soil disturbances/cultivation May stimulate SOM mineralization due to soil aeration and degradation of soil aggregates, but SOM effects may be offset by improved plant growth (Murphy and Ebdon, 2013); soil disturbance does not appear to significantly alter the soil microbiome once adapted to typical lawn edaphic and management conditions (Yao et al, 2006;Bartlett et al, 2007;Shi et al, 2012;Crouch et al, 2017) These potential effects may vary by the intensity of each management practice, geographically, and under different management goals. This review and this table present preliminary attempts to link multiple management practices to different soil nutrient cycles via impacts on the soil microbiome.…”

“…Soil microorganisms mediate many fundamental belowground ecological processes, such as nutrient cycling and SOM accumulation or depletion, thus even typical urban grassland management practices such as mowing, the return or removal of mowed-off grass clippings, irrigation, fertilization, lawn species composition, or soil disturbance, have the potential to affect soil microbial structure and function. Changes in soil microbial processes may have tremendous influence on long-term C and N dynamics, including determining the fate of SOM in urban grasslands (Shi et al, 2012;Zhalnina et al, 2015;Crouch et al, 2017;Wang et al, 2017). Shifts in the composition of the soil microbiome could signify alterations to microbial functions that regulate biogeochemical transformations and other valuable ecosystem services (Shi et al, 2007(Shi et al, , 2012.…”

“…Shifts in the composition of the soil microbiome could signify alterations to microbial functions that regulate biogeochemical transformations and other valuable ecosystem services (Shi et al, 2007(Shi et al, , 2012. Despite the complexity and heterogeneous nature of soils, research has shown that soil microbiota respond to changes in environmental conditions and management practices that are at resolutions detectable with standard sequencing approaches (Janssen, 2006;Fierer et al, 2009a;Crouch et al, 2017;Wang et al, 2017). While relative abundances and diversity matrices of broad taxa can be tracked to show microbiome structural changes, soil functional attributes are also detectable (Schimel et al, 2005;Isobe and Ohte, 2014;Reisinger et al, 2016;Wang et al, 2017).…”

Prokaryotic taxa play keystone roles in the soil microbiome associated with woody perennial plants in the genus Buxus

“…The importance of these microbial groups has motivated efforts to understand their ecology in global ecosystems and develop ways to manipulate their impacts on plants through management or plant breeding (Bakker, Manter, Sheflin, Weir, & Vivanco, ; Fierer, ; Walters et al, ). Despite the potential to leverage the microbial diversity in soil to influence plant growth, aside from work in turfgrass (Beirn et al, ; Crouch, Carter, Ismaiel, & Roberts, ), relatively little research has focused on plants that are cultivated for their ornamental traits.…”