Orr, Alexandra, Ecosystem Science and Management, Penn State University, 222 Forest Resources Building, University Park, Pennsylvania, 16802, aso124@psu.edu; Boyer, Elizabeth, Ecosystem Science and Management, Penn State University, 304 Forest Resources BL, University Park, Pennsylvania, 16802, ewb100@psu.edu; Duncan, Jon, Ecosystem Science and Management Penn State University 306 Forest Resources Building University Park Pennsylvania, 16802, jmduncan@psu.edu; Groh, Tyler, Ecosystem Science and Management, tag5611@psu.edu.
Water temperature is an important physical property of stream and river networks, influencing in-stream biochemical processes, water quality, and aquatic life. The critical zone is the earth’s outer skin from bedrock to treetop. Critical zone processes in the atmosphere, lithosphere, and hydrosphere all influence a stream’s thermal regime, and anthropogenic effects such as changes in land-use or natural flow patterns, can greatly impact stream temperature and ecosystem processes. The Spring Creek Watershed in Centre County, Pennsylvania is a karstic, mixed land use watershed that has undergone steady development over the last century. We analyzed 20 years of stream temperature and flow data to examine natural and anthropogenic factors contributing to the variability in stream temperature in sub-basins of varying geology and land use. Results suggest that streams with less groundwater contribution and higher levels of impervious cover exhibit the highest average and maximum summer temperatures respectively. Further, impervious cover can cause thermal surges following summer storm events that can increase stream temperatures rapidly to temperatures unsuitable for certain aquatic species. Quantifying stream reaches that may experience temperatures outside critical ecological habitat ranges can help to prioritize planning for streambank restoration, stormwater management and other innovative strategies.
temperature, karst geology