Page Banner

United States Department of Agriculture

Agricultural Research Service

Research Project: SUSTAINABLE AGRO-ECOSYSTEMS THAT CONTROL SOIL EROSION AND ENHANCE THE ENVIRONMENT

Location: Wind Erosion and Water Conservation Research

Title: Pyrosequencing reveal distinct bacteria are carried in different wind eroded sediments from the same soil

Authors
item Gardner, Terrence -
item Acosta-Martinez, Veronica
item Senwo, Zachary -
item Calderon, Francisco
item Dowd, Scot -
item Baddock, Matthew -
item Van Pelt, Robert
item Zobeck, Teddy

Submitted to: Journal of Environmental Quality
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: February 1, 2012
Publication Date: June 1, 2012
Citation: Gardner, T., Acosta Martinez, V., Senwo, Z., Calderon, F.J., Dowd, S., Baddock, M., Van Pelt, R.S., Zobeck, T.M. 2012. Pyrosequencing reveal distinct bacteria are carried in different wind eroded sediments from the same soil. Journal of Environmental Quality. 41(3):744-753.

Interpretive Summary: Sediments from wind erosion on agricultural soils have become a national concern because of the effects of the “fugitive” dust on visibility, air quality and the potential effects on human health. ARS scientists from Texas and Colorado utilized a novel (DNA sequencing) technique, named pyrosequencing to provide enhanced exploration into the microbes being lost from soil due to wind erosion. Our study evaluated the bacterial diversity of different sediments collected from three different organic-rich soils in Michigan by using a portable field wind tunnel instrument. Interestingly, the new, powerful sequencing technique revealed: (1) bacteria carried in sediment and dust were fingerprints of the soil source, although their distribution (predominance) may vary depending on the soil characteristics as certain bacteria may possibly be more protected in soil surfaces than others; (2) Coarse sediment (> 106 µm) showed higher bacterial diversity than fine dust (< 106 µm) and; (3) Certain bacteria were more predominant in fine dust (Bacteroidetes, Cloroflexi and Firmicutes) than coarse sediment (Proteobacteria and Acidobacteria), revealing different locations and niches of bacteria in soil. Our study provides evidence that eroded sediments carry away active organic soil particulates that participate readily in reactions containing key microbes involved in soil biogeochemical processes, which can have a negative impact on the quality and functioning of the soil source.

Technical Abstract: Little is known about the microbial communities carried in wind-eroded sediments from various soil types and land management systems. A novel technique, named pyrosequencing, promises to expand our understanding of the vast microbial diversity of soils and eroded sediments as it can sequence between 10-100 times higher number of DNA fragments than previous techniques (traditional cloning), providing enhanced exploration into what microbes are being lost from soil due to wind erosion. Our study evaluated the bacterial diversity of coarse sized fractions of wind-eroded sediment as well as dust collected from three different organic-rich soils in Michigan using a portable field wind tunnel. Our findings suggested: (1) Bacteria carried in the coarser sediment and dust were effective fingerprints of the soil source, although their distribution (predominance) may vary depending on the soil characteristics as certain bacteria may possibly be more protected in soil surfaces than others; (2) Coarser wind-eroded sediment (> 106 µm) showed higher bacterial diversity than fine dust (< 106 µm) and; (3) Certain bacteria were more predominant in fine dust (Bacteroidetes, Cloroflexi and Firmicutes) than coarse sediment (Proteobacteria and Acidobacteria), revealing different locations and niches of bacteria in soil, which depending on wind erosion processes, can have important implications on the soil sustainability and functioning. Our study provides evidence that eroded sediments remove the active labile organic soil particulates containing key microorganisms involved in soil biogeochemical processes, which can have a negative impact on the quality and functioning of the parent soil.

Last Modified: 10/25/2014