AN006
Lotic Intersite Nitrogen eXperiment II (LINX II): a cross-site study of the effects of anthropogenic land use change on nitrate uptake and retention in 72 streams across 8 different biomes (2003 – 2006).

CREATOR(S): Clifford N. Dahm, Walter K. Dodds, Stanley V. Gregory, Sherri L. Johnson, Judy L. Meyer, Patrick J. Mulholland, Jackson R. Webster, Nancy B. Grimm, William H. McDowell, Jennifer L. Tank, Stephen K. Hamilton, Bruce J. Peterson, H. Maurice Valett, Robert O. Jr. Hall

PRINCIPAL INVESTIGATOR(S): Patrick J. Mulholland, Clifford N. Dahm, Walter K. Dodds, Stanley V. Gregory, Nancy B. Grimm, Robert O. Jr. Hall, Stephen K. Hamilton, Sherri L. Johnson, Bruce J. Peterson, William H. McDowell, Judy L. Meyer, Jennifer L. Tank, H. Maurice Valett, Jackson R. Webster

ORIGINATOR(S): Patrick J. Mulholland

OTHER RESEARCHER(S): Clay P. Arango, Linda R. Ashkenas, Jake J. Beaulieu, Melody J. Bernot, Amy J. Burgin, Lee W. Cooper, Chelsea L. Crenshaw, Stuart G. Findlay, Ashley M. Helton, Laura T. Johnson, Eugènia Martí, Jeff L. Merriam, B. R. Niederlehner, Jonathan M. O'Brien, Geoffrey C. Poole, Jody D. Potter, Richard W. Sheibley, Daniel J. Sobota, Suzanne M. Thomas, Kym Wilson, Lydia Zeglin

DATA SET CONTACT PERSON: Linda R. Ashkenas

ABSTRACTOR: Linda R. Ashkenas

METHOD CONTACT: Stephen K. Hamilton

DATA SET CREDIT:

This work was supported by National Science Foundation (NSF) grant DEB-0111410 to the University of Tennessee, NSF Long Term Ecological Research (LTER) grants to some of the individual sites, and numerous smaller grants and fellowships to other institutions. More than 100 students and scientists gathered the information for the experiments. The NSF LTER network, U.S. Forest Service, National Park Service and many municipal and private landowners facilitated the field research. The NSF DEB provided supplemental funding to organize the online database. When using these data, we suggest you cite one or both of these two core LINX papers as appropriate: Mulholland, P. J, , R. O. Hall, Jr., D. J. Sobota, W. K. Dodds, S. Findlay, , N. B. Grimm, S. K. Hamilton, W. H. McDowell, J. M. O’Brien, J. L. Tank, L.R. Ashkenas, L. W. Cooper, C. N. Dahm, S. V. Gregory, S. L. Johnson, J. L. Meyer, B. J. Peterson, G. C. Poole, H. M. Valett, J. R. Webster, C. Arango, J. J. Beaulieu, M. J. Bernot, A. J. Burgin, C. Crenshaw, A. M. Helton, L. Johnson, B. R. Niederlehner, J. D. Potter, R. W. Sheibley, and S. M. Thomas. 2009. Nitrate removal in stream ecosystems measured by 15N addition experiments: denitrification. Limnology and Oceanography 54: 666-680. Hall, R. O., Jr., J. L. Tank, D. J. Sobota, P. J. Mulholland, J. M. O’Brien, W. K. Dodds, J. R. Webster, H. M. Valett, G. C. Poole, B. J. Peterson, J. L. Meyer, W. H. McDowell, S. L. Johnson, S. K. Hamilton, N. B. Grimm, S. V. Gregory, C. N. Dahm, L. W. Cooper, L.R. Ashkenas, S. M. Thomas, R. W. Sheibley, J. D. Potter, B. R. Niederlehner, L. Johnson, A. M. Helton, C. Crenshaw, A. J. Burgin, M. J. Bernot, , J. J. Beaulieu, C. Arango. 2009. Nitrate removal in stream ecosystems measured by 15N addition experiments: total uptake. Limnology and Oceanography 54: 653-665.

METADATA CREATION DATE:

9 Nov 2012

MOST RECENT METADATA REVIEW DATE:

19 Feb 2015

KEYWORDS:

stream ecology, nitrogen cycling, aquatic ecosystems

PURPOSE:

Excess nitrogen in the environment from fertilizers, crops, human and animal waste and air pollution is currently a major issue in freshwater and coastal marine ecosystems. Recent evidence suggests that small streams in the headwaters of river networks are particularly important in taking up and retaining nitrogen, thereby potentially alleviating downstream pollution effects. However, anthropogenic changes to land use, including conversion to agriculture and urban areas, may be reducing this retentive capacity. This study was designed to examine these impacts, using standardized experimental protocols, at 72 headwater streams in 8 biomes across the North America. A key technique was the use of experimental additions of nitrate enriched in the stable isotope of nitrogen, 15N. This study focused on nitrate (NO3-), one of the major forms of nitrogen pollution in aquatic ecosystems. Using a spatially explicit model of river networks, the results from the experimental studies were expanded to a landscape analysis of larger river basins.

METHODS:

Experimental Design - AN006:

Description: See LINX 2 Stream 15N Experiment Protocols.pdf in 'Related Materials' link from main abstract page.

Field Methods - AN006:

Description: See LINX 2 Stream 15N Experiment Protocols.pdf in 'Related Materials' link from main abstract page.

Laboratory Methods - AN006:

Description: See LINX 2 Stream 15N Experiment Protocols.pdf in 'Related Materials' link from main abstract page.

SITE DESCRIPTION:

See SiteID_Notes document as well as Data1 table. Eight of the 72 streams were affiliated with LTER sites.

TAXONOMIC SYSTEM:

None

GEOGRAPHIC EXTENT:

Eight different clusters of sites were represented: northern deciduous forest (Massachusetts, Michigan/Indiana); southern deciduous forest (North Carolina/Georgia); tallgrass prairie (in Kansas); shrub steppe (Wyoming); desert (New Mexico/Arizona); wet coniferous forest (Oregon) and tropical forest (Puerto Rico). Within each of these eight clusters, nine different stream reaches were selected for the study for a total of 72 sites. The nine streams were further subdivided into reference, agriculture, and urbanized sites.

MEASUREMENT FREQUENCY:

variable from continuous to single sample

PROGRESS DESCRIPTION:

Complete

UPDATE FREQUENCY DESCRIPTION:

notPlanned

CURRENTNESS REFERENCE:

Ground condition

RELATED MATERIAL:

See List of LINXII publications from main data abstract page under 'Related Materials'.