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Title: Environmental Calcium Controls Alternate Physical States of the Caulobacter Surface Layer

Authors:
; ; ; ; ; ; ; ; ;
Publication Date:
Research Org.:
SLAC National Accelerator Lab., Menlo Park, CA (United States)
Sponsoring Org.:
USDOE Office of Science (SC), Basic Energy Sciences (BES) (SC-22); National Science Foundation (NSF)
OSTI Identifier:
1352491
Report Number(s):
SLAC-PUB-16957
Journal ID: ISSN 0006-3495
DOE Contract Number:
AC02-76SF00515
Resource Type:
Journal Article
Resource Relation:
Journal Name: Biophysical Journal; Journal Volume: 112; Journal Issue: 9
Country of Publication:
United States
Language:
English
Subject:
OTHER

Citation Formats

Herrmann, Jonathan, Jabbarpour, Fatemeh, Bargar, Paul G., Nomellini, John F., Li, Po-Nan, Lane, Thomas J., Weiss, Thomas M., Smit, John, Shapiro, Lucy, and Wakatsuki, Soichi. Environmental Calcium Controls Alternate Physical States of the Caulobacter Surface Layer. United States: N. p., 2017. Web. doi:10.1016/j.bpj.2017.04.003.
Herrmann, Jonathan, Jabbarpour, Fatemeh, Bargar, Paul G., Nomellini, John F., Li, Po-Nan, Lane, Thomas J., Weiss, Thomas M., Smit, John, Shapiro, Lucy, & Wakatsuki, Soichi. Environmental Calcium Controls Alternate Physical States of the Caulobacter Surface Layer. United States. doi:10.1016/j.bpj.2017.04.003.
Herrmann, Jonathan, Jabbarpour, Fatemeh, Bargar, Paul G., Nomellini, John F., Li, Po-Nan, Lane, Thomas J., Weiss, Thomas M., Smit, John, Shapiro, Lucy, and Wakatsuki, Soichi. 2017. "Environmental Calcium Controls Alternate Physical States of the Caulobacter Surface Layer". United States. doi:10.1016/j.bpj.2017.04.003. https://www.osti.gov/servlets/purl/1352491.
@article{osti_1352491,
title = {Environmental Calcium Controls Alternate Physical States of the Caulobacter Surface Layer},
author = {Herrmann, Jonathan and Jabbarpour, Fatemeh and Bargar, Paul G. and Nomellini, John F. and Li, Po-Nan and Lane, Thomas J. and Weiss, Thomas M. and Smit, John and Shapiro, Lucy and Wakatsuki, Soichi},
abstractNote = {},
doi = {10.1016/j.bpj.2017.04.003},
journal = {Biophysical Journal},
number = 9,
volume = 112,
place = {United States},
year = 2017,
month = 5
}
  • Carbon stocks and fluxes in inland waters have been identified as important, but poorly constrained components of the global carbon cycle. In this study, we compile and analyze particulate organic carbon (POC) concentration data from 1145 U.S. Geological Survey (USGS) hydrologic stations to investigate the spatial variability and environmental controls of POC concentration. We observe substantial spatial variability in POC concentration (1.43 ± 2.56 mg C/ L, Mean ± Standard Deviation), with the Upper Mississippi River basin and the Piedmont region in the eastern U.S. having the highest POC concentration. Further, we employ generalized linear regression models to analyze themore » impacts of sediment transport and algae growth as well as twenty-one other environmental factors on the POC variability. Suspended sediment and chlorophyll-a explain 26% and 17% of the variability in POC concentration, respectively. At the national level, the twenty-one selected environmental factors combined can explain ca. 40% of the spatial variance in POC concentration. Overall, urban area and soil clay content show significant negative correlation with POC concentration, while soil water content and soil bulk density correlate positively with POC. In addition, total phosphorus concentration and dam density covariate positively with POC concentration. Furthermore, regional scale analyses reveal substantial variation in environmental controls determining POC concentration across the 18 major water resource regions in the U.S. The POC concentration and associated environmental controls also vary non-monotonically with river order. These findings indicate complex interactions among multiple factors in regulating POC production over different spatial scales and across various sections of the river networks. This complexity together with the large unexplained uncertainty highlight the need for consideration of non-linear processes that control them and developing appropriate methodologies to track the transformation and transport of carbon in these terrestrial-aquatic systems. Such scientific advancements will also benefit greatly the Earth system models that are currently deficient in representing properly this component of global carbon cycle.« less
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