Water Resources Research Act Program

Details for Project ID 2009AR215B

Land-use effects on resistance and resilience of stream metabolism to flood events in Ozark Highland headwater streams

Institute: Arkansas
Year Established: 2009 Start Date: 2009-03-01 End Date: 2010-02-28
Total Federal Funds: $20,000 Total Non-Federal Funds: $40,000

Principal Investigators: Michelle Evans-White

Abstract: Climate change models predict altered temperature and precipitation patterns across the globe. Altered precipitation frequency, amounts, and seasonality will likely alter nutrient, contaminant, sediment, and organic matter delivery to streams as well as in-stream processing of these materials. Watershed vegetation structure and land-use (e.g., urban, agriculture) can also mediate the delivery of water, nutrients, organic matter and sediments to streams. Therefore, studies examining the resistance or resilience of stream ecosystem processes to hydrologic disturbance within the major terrestrial biomes and major land-uses within those biomes are needed to predict the potential consequences of climate change for stream ecosystems. The Ozark Highlands region of Northwest Arkansas is a patchwork of predominantly forested watersheds to increasingly agricultural or urban watersheds, which lends well to natural experiments examining ecology within these different stream types. Water quality within this region affects water quality across state boundaries and in the Gulf of Mexico. The main objective of the proposed research is to determine whether resistance and resilience of stream metabolism, which includes gross primary production, ecosystem respiration, and net ecosystem production, to flood events differs among headwater streams draining watersheds dominated by forest, urban, or agricultural land-use in the Ozark Highlands. Stream metabolism will be measured in 12 streams (4 each from predominantly forested, urban, and agricultural watersheds) and related to measures of in-stream light levels, dissolved nutrients, turbidity, benthic organic matter standing stocks, periphyton biomass, grazer biomass, substrate size, and flood intensity. The proposed research would provide infrastructure in the form of multi-parameter sondes to help monitor water quality and to study the effects of regional climate and land-use change on stream ecosystems in northwest Arkansas. Infrastructure and funds would also be used to support spin-off projects for undergraduate and graduate students.