Belowground response of prairie restoration and resiliency to drought

• Published in: Agriculture, ecosystems & environment ecosystems & environment, 2018-11, Vol.266 (C), p.122-132
• Main Authors: Upton, Racheal N., Bach, Elizabeth M., Hofmockel, Kirsten S.
• Format: Article
• Language: English
• Subjects: Agricultural land; Agricultural management; Agricultural production; Agriculture; Alternative crops; bacteria; Biodiversity; Biofuels; Biological activity; Biomass; Cellulose; Community structure; Corn; Cropping systems; Divergence; Drought; Ecosystem services; Ecosystems; Environmental changes; Environmental restoration; Environmental Sciences & Ecology; Enzymatic activity; Enzyme activity; Fertilization; fungi; Land use; Management systems; Microbial activity; microbial ecology; Microbiomes; Microorganisms; Monoculture; Nitrogen; Nutrients; Plant communities; Plant diversity; Plant populations; prairie restoration; Prairies; Redundancy; Renewable energy; Resilience; resiliency; Restoration; Sequences; soil; Soil dynamics; Soil management; Soil microorganisms; Soil structure; Soils; Structure-function relationships; Sustainability; tallgrass prairie
• ISSN: 0167-8809; 1873-2305
• DOI: 10.1016/j.agee.2018.07.021

•Planted prairie bioenergy systems with high plant diversity supported greater microbial diversity than corn systems.•Microbial activity increased with increasing plant root inputs and greater precipitation.•Prairies with increased microbial diversity exhibited increased functional resiliency, as measured by cellulose-degrading enzyme activity, than corn systems. Agricultural land use is a major threat to biodiversity and ecosystem functions in tallgrass prairies. However, there are proposed bioenergy systems that can use biomass harvested from restored tallgrass prairie, creating a potential free market incentive for landowners to restore prairies. These alternative management practices may alter associated soil microbial communities and their ecosystem services. We examined changes in soil microbial community structure, function, and resiliency to drought following two prairie restorations from row-crop agriculture and through subsequent succession in a fertilized and unfertilized tallgrass prairie. The soil microbial community structure was assessed through amplicon (16S and ITS) sequencing, function through potential extracellular enzyme activity, and resiliency indices were calculated for both microbial diversity measures and extracellular enzyme activity. We hypothesized that 1) distinct soil microbial communities in each management system will continue to develop over time reflecting the extent of divergence between the plant communities, due to the strong selective forces plant communities have on the soil microbiome. 2) Microbial extracellular enzymatic function will continue to diverge between the management systems across sampling years. 3) We will see increased resiliency to drought in the prairies potentially due to the greater diversity in this management system for the microbial and plant community, creating a possible enhancement in functional redundancy. Our experiment demonstrates that soil microbial communities continue to diverge from row-crop agriculture as prairie restoration progresses. Planted prairie bioenergy systems with higher plant diversity supported greater microbial diversity than corn systems. Corn monocultures were less resistant to drought stress, as evidenced by decreased microbial activity and richness. Prairies with increased microbial diversity exhibited increased functional resiliency than corn systems, as measured by cellulose-degrading enzyme activity. Prairies that received nitrogen fertilization maintained high m