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Title: Remote Sensing of Water Quantity and Quality in Geospatial Education: Lake Sidney Lanier, Georgia, USA
To increase geospatial awareness about local water resources, our team developed learning resources for the 150 km² Lake Sidney Lanier reservoir located in North Georgia, USA. The reservoir is vital for hydroelectric power generation, recreation, tourism, and consumptive uses. Using geospatial analysis in Google Earth Engine (GEE), we analyzed precipitation trends in the watershed using Climate Hazards Group InfraRed Precipitation with Station (CHIRPS) data. We also quantified expansion and contraction of reservoir surface area using Landsat-derived Global Surface Water data. As Lake Sidney Lanier is a managed reservoir, surface water extent fluctuations are related to climatic variables, consumptive use, and hydropower generation. Water temperature varies based on seasonality, water depth, water clarity, and lake stratification. Changing temperature dynamics affect ecosystem health and determine other important water quality parameters such as dissolved oxygen concentrations. Landsat 8 Thermal Infrared Sensor (TIRS) data were used to examine temperature trends over multiple years and investigate the timing of lake stratification and mixing. Highly turbid waters are associated with pollutants and lower water quality and can affect ecosystem productivity by minimizing sunlight penetration into the water column. Sentinel 2 MSI data were processed using a turbidity algorithm to analyze temporal trends and spatial correlations with more » reservoir inflows. Finally, high concentrations of chlorophyll a were used as a proxy to identify harmful algal blooms. The spatial differences in headwaters and near-dam locations were examined and near real-time satellite data were explored for potential development of early-warning systems to protect ecosystem and human health. « less
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Apalachicola-Chattahoochee-Flint Waters Conference: Shared Resources in Changing Times. Albany, GA
Sponsoring Org:
National Science Foundation
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  1. Integration of remote sensing techniques and Environmental Science methodologies in place-based curriculum design creates unique learning opportunities. To promote introductory-level student engagement with STEM, our team designed a set of multidisciplinary teaching materials to intensely examine a single location: the Lake Sidney Lanier watershed of North Georgia, USA. Using a combination of scientific approaches from a variety of disciplines, course exercises encourage students to holistically learn about environmental conditions within the watershed. In addition, the learning materials require students to contemplate the process of knowledge-formation by considering the limitations and potential applications of different scientific approaches. Remote sensing exercises are embedded throughout the course content and include analysis of historic aerial imagery, Landsat-derived dynamic surface water extent, google timelapse land cover change, Sentinel 2 spectral bands, and evaluation of lidar-derived topography. Learning resources were intentionally designed to seamlessly integrate remote sensing approaches and traditional environmental science methods. Fundamental spatial concepts of scale and connectivity are considered using interdisciplinary approaches and local data. The environmental science theory of landscape ecology is presented alongside remote sensing concepts of spatial and temporal resolution. This allows students to think about the diverse ways scientists understand scale, pattern, and the definition of “place”. Multiple datamore »sources are also provided for each topic. For example, remote sensing imagery is used to investigate surface water conditions during drought and high-rainfall time periods. In addition, USGS streamgage river discharge data and rainfall estimates are provided for students to examine drought history using multiple parameters. Lastly, sensor deployment and limitations of each data source are described so that students understand both the history of place as well as the process and development of science. Through the use of a place-based curriculum design and interdisciplinary lab exercises, students gain a holistic understanding of a regional watershed.« less
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GLM–AED results indicated that the external P load would need to be reduced to about 4,060 kg/yr, a 57-percent reduction from that measured in 2014–18, to eliminate the occurrence of MOMs less than 5 mg/L during more than 75 percent of the years (the target provided by the WDNR). Large reductions in external P loading are expected to have an immediate effect on the near-surface TP concentrations and metalimnetic DO concentrations in Green Lake; however, it may take several years for the full effects of the external-load reduction to be observed because internal sediment recycling is an important source of P for the following spring.« less
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