Geology topics

Research about Upper Tennessee River Basin

Source-linked reports with geographic coverage including Upper Tennessee River Basin.

2 recordsLinked to original sources

USGS2006

Integrating human impacts and ecological integrity into a risk-based protocol for conservation planning

Conservation planning aims to protect biodiversity by sustainng the natural physical, chemical, and biological processes within representative ecosystems. Often data to measure these components are inadequate or unavailable. The impact of human activities on ecosystem processes complicates integrity assessments and might alter ecosystem organization at multiple spatial scales. Freshwater conservation targets, such as populations and communities, are influenced by both intrinsic aquatic properties and the surrounding landscape, and locally collected data might not accurately reflect potential impacts. We suggest that changes in five major biotic drivers—energy sources, physical habitat, flow regime, water quality, and biotic interactions—might be used as surrogates to inform conservation planners of the ecological integrity of freshwater ecosystems. Threats to freshwater systems might be evaluated based on their impact to these drivers to provide an overview of potential risk to conservation targets. We developed a risk-based protocol, the Ecological Risk Index (ERI), to identify watersheds with least/most risk to conservation targets. Our protocol combines risk-based components, specifically the frequency and severity of human-induced stressors, with biotic drivers and mappable land- and water-use data to provide a summary of relative risk to watersheds. We illustrate application of our protocol with a case study of the upper Tennessee River basin, USA. Differences in risk patterns among the major drainages in the basin reflect dominant land uses, such as mining and agriculture. A principal components analysis showed that localized, moderately severe threats accounted for most of the threat composition differences among our watersheds. We also found that the relative importance of threats is sensitive to the spatial grain of the analysis. Our case study demonstrates that the ERI is useful for evaluating the frequency and severity of ecosystemwide risk, which can inform local and regional conservation planning.

Tennessee↗

USGS2002

Water quality of springs in the Valley and Ridge Physiographic Province in the upper Tennessee River basin, 1997

In the fall of 1997, 35 springs in the carbonate rocks of the Valley and Ridge Physiographic Province of the upper Tennessee River Basin were sampled for nutrients, fecal-indicator bacteria, pesticides, and volatile organic compounds (VOCs) as part of the National Water-Quality Assessment (NAWQA) Program. About half of the randomly selected springs were used as untreated domestic drinking-water supplies, either by direct pumpage from the spring or as roadside filling sites. Nutrient concentrations generally were less than 2 milligrams per liter. Nitrate, the most frequently detected nutrient, ranged from 0.091 to 2.17 milligrams per liter, with a median concentration of 1.16 milligrams per liter. Fecal-indicator bacteria were detected at all springs, with total coliform ranging from 10 to 1,900 colonies per 100 milliliters and Escherichia coli ranging from less than 1 to 660 colonies per 100 milliliters. Concentrations of bacteria at all springs sampled exceeded bacteriological drinking-water standards for public water supplies. Eight pesticides or degradation byproducts, all below U.S. Environmental Protection Agency drinking-water maximum contaminant levels, were detected in samples from 24 of the 35 springs. The most frequently detected pesticide was atrazine and its degradation byproduct, deethylatrazine, which were found in water samples from 57 and 54 percent of the springs, respectively. Some pesticides were detected more frequently in water samples from the springs than in ground-water samples from wells in similar NAWQA studies nationwide. Concentrations of VOCs in the springs also were below maximum contaminant levels. The most frequently detected VOCs were chloroform (20 springs), methyl chloride (18 springs), styrene (12 springs), and tetrachloroethene (11 springs). These detection frequencies of VOCs are consistent with the national NAWQA results when comparing wells and springs in a mixture of urban and rural land uses.

Upper Tennessee River Basin↗