Impact/Purpose:

The overall objective of this task is to identify or develop useful indicators of organic waste enrichment in aquatic systems that are easily measured and based on basic underlying ecosystem processes so that they will be widely applicable. These activities will primarily contribute to an APG within Long Term Goal 2 of the Water Quality Research Program Multiyear Plan: the 2008 APG on equipping EPA Regions, States, and Tribes with knowledge, skills and tools to determine the causes of impairments for freshwater and coastal systems required in various regulations and will also contribute to EPA Strategic Plan 2003-2008 Sub-objective 2.2.2: Improve Coastal and Ocean Waters. Activities that address the 2008 Water Quality APG will focus primarily on small streams of the Georgia Piedmont, which receive human and agricultural waste inputs. The activities related to EPA Sub-objective 2.2.2 will focus on the nearshore marine ecosystem of the Pacific Ocean, which receives treated wastes from the approximately 15 million people who live in the coastal zone of southern California and northern Baja California, Mexico, and on the nearshore marine ecosystem of the Gulf of California, which receives little anthropogenic pollution. The indicators that will be evaluated or developed will include concentrations of trace gases (N2O, CH4, and CO2), dissolved oxygen (DO), nutrients, and dissolved organic matter (DOM), other key parameters such as temperature, conductivity or salinity, flow rate, alkalinity, and pH, rates of key processes such as denitrification and DO consumption, and stable isotope ratios of various pools and substrates such as plants, animals, sediments, and DO.

Description:

Loadings of excess organic wastes and associated nutrients to aquatic systems has numerous deleterious consequences with respect to the ecosystem services provided by these important ecosystems including perturbation of organic matter and nutrient cycling rates, reduction in dissolved oxygen levels, and undesirable changes in aquatic biological communities. The primary goal of this task is to evaluate and develop indicator tools to diagnose aquatic ecosystem stress due to organic waste enrichment and to improve understanding of the underlying ecosystem properties and processes upon which the indicators are based.

Record Details:

Record Type:PROJECT

Start Date:10/01/2004

Projected Completion Date:09/01/2006

OMB Category:Other

Record ID: 84967

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Project Information:

Progress :I have continued to analyze previously collected data and am working on a manuscript with a former NRC postdoc which evaluates the influence of land use on DOM concentrations and major element (C,N,P) composition in small Georgia streams and also have prepared and presented or am preparing to present several talks and/or posters describing this work. I have also arranged for some equipment to be repaired and other equipment to be acquired to allow measurements planned for this year. I also analyszed the stable C and N isotope ratios of many samples of marine organisms, marine sediments, and particulates from wastewater treatment plants for the purpose of tracing wastewater C and N input to the nearshore marine food web from wastewater this spring. I hosted a graduate student from the Instituto de Investigaciones Oceanolõgicas (IIO) of the Universidad Autõnoma de Baja California (UABC) this summer for two weeks during which we measured methane concentrations in Pacific Ocean water by GC. I also hosted an IIO/UABC professor and another graduate student for two weeks this fall during which we performed compound specific isotope analysis on extracts from marine sediments, wastewater treatment plants, and other point sources for the purpose of tracing the input of contaminants to the nearshore Pacific Ocean. This summer I attended a week long WASP model training course for the purpose of learning more about needed inputs for improving this important model. I have also had extensive discussions with modelers from ERD and from the academic community about model development needs and have refined my planned research to make it more compatible with model development needs. I have had extensive discussions with Region 4 personnel about sediment oxygen demand (SOD) and hope to participate in the testing of a simple ORD-developed SOD method with the more complex method used by Region 4 to determine if the simpler technique might provide useful data for model improvement. I also attended a training course about groundwater/ surface water interactions this fall and will incorporate this important process in my research if possible.

The following talks related to this task have been presented in addition to those listed in TIMS:

Biogeochemical indicators in small Piedmont streams, seminar presented to EPA Region 8 scientific staff, Denver, Co, November 4, 2003.

Stable carbon isotope ratio and composition of microbial fatty acids in Rondonia pasture and forest soils, presented at the Second Workshop on Biogeochemical Changes Associated with Agroecosystems, Third LBA Scientific Conference, Brasilia, Brazil, July 25-26, 2004, with M. Molina, J. E. Cox, P. A. Stuedler, and C. C. Cerri.

Relevance :Small streams are critical components of watersheds, exhibiting high rates of organic matter, nutrient and contaminant cycling, but are not as well protected by regulations as they should be. Also, they are so numerous that detailed study of even a significant fraction of this is impractical so development of easily measured but effective indicators of their function could have a considerable impact with regards to their protection. The ocean covers over 70% of the Earth's surface and plays a critical role in supplying food and recreation to humans and provides critical global ecosystem services. Protection of oceanic ecosystems would also be greatly enhanced by development of effective indicators of their function.

Clients :Office of Water (Richard Sumner, 541 754 4444) and Region 4 (Jennifer Derby, 404 562 9401)

Project IDs:

ID Code :20162

Project type :OMIS