Abstract
Manure amendments are a common soil amendment in forage and row cropping systems used to provide plant-available nutrients, build soil organic matter, and enhance soil health. Many of the benefits of manure applications are thought to be driven via their impacts on soil microbial communities. However, manure amendments may also introduce potential undesirable microbes (pathogens, or those with antibiotic resistance elements) to soils. Despite the widespread use of manure amendments and their importance in agricultural systems, the forces governing the assembly of bacterial communities in soil in response to manure amendments are poorly characterized, limiting our ability to predict their impacts on soil communities. We constructed soil microcosms using five soils from different locations to investigate the impacts of liquid dairy manure on bacterial communities. Moreover, we used combinations of autoclaved liquid dairy manure and soils to determine the roles of abiotic and biotic factors in the response of indigenous soil communities to manure and the fate of manure-borne bacteria. Bacterial amplicon sequence variants (ASVs) that responded to manure amendment were largely dependent on soil origin. Initial shifts in soil communities after manure amendment were driven by the introduction of manure-borne taxa. However, introduced taxa died off rapidly while some indigenous taxa increased in relative abundance over time. Introduced taxa died off even in the absence of indigenous microbiota, suggesting that the soil abiotic environment is a strong barrier to colonization by manure-borne bacteria. Finally, autoclaved manure amended to soil elicited a similar response from indigenous soil microbes as did live manure, indicating that organic matter, nutrients, or other physiochemical factors associated with manure amendments are responsible for changes in indigenous soil populations.
Original language | English (US) |
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Article number | 104618 |
Journal | Applied Soil Ecology |
Volume | 180 |
DOIs | |
State | Published - Dec 2022 |
Bibliographical note
Funding Information:We thank Curtis Dell, USDA-ARS University Park, PA; David Tarkalson, USDA-ARS Kimberly, ID; and the Minnesota Long-Term Agricultural Research Network for supplying soil for this experiment. Melinda Dornbusch, Sue Miller, and Ted Jeo were instrumental in the setup of microcosms. Mention of trade names or commercial products in this publication is solely for the purpose of providing specific information and does not imply recommendation or endorsement by the U.S. Department of Agriculture. USDA is an equal opportunity provider and employer. This research was supported by the U.S. Department of Agriculture, Agricultural Research Service (project no. 5062-12210-004-000-D).
Publisher Copyright:
© 2022
Keywords
- Community assembly
- Dairy manure
- Ecological resistance
- Environmental filters
- Microbial dynamics
- Soil microbiome