C. Brannon Andersen

Abundance of Boyeria vinosa larvae in the Enoree River basin, USA: chemical, physical, and biological correlates (Odonata: Aeshnidae)

Abstract Boyeria vinosa is a common anisopteran in the southeastern United States. Here we describe relationships between the abundance of B. vinosa larvae and the chemical, physical and biological properties of the Enoree River of South Carolina and nine of its tributary stream systems. Chemical profiles were conducted weekly for seven weeks at 63 sites in May-July 1999 and at 64 sites in May-July 2000. Fish, salamanders, crayfish, and odonate larvae were collected once at each site by electrofishing and seining, and were counted, sorted, and preserved. The abundance (number/sample) of B. vinosa was positively correlated with stream means for pH, bicarbonate, silicon, magnesium, and calcium (p < 0.01). Also, B. vinosa were more abundant in streams with a higher frequency of sandy bottoms sites (r = 0.622, p = 0.05). At the site scale, sites with B. vinosa had significantly more crayfish, fish, and other odonates, higher pH, and dissolved oxygen, and less chloride than sites without B. vinosa (Mann-Whitney U tests, p < 0.05). Where B. vinosa were present, abundance was positively correlated with fish abundance, odonate abundance, pH, conductivity, and concentrations of sodium, calcium, magnesium, bicarbonate, bromine, silicon, and aluminum (p < 0.05). As such, larval abundance of B. vinosa was strongly correlated with chemical and physical parameters at both site and stream scales, but only covaried with the abundance of other organisms at the site scale. Larval abundance did not correlate with the abundance of predatory centrarchid fish at either scale.

Chapter 24 Relations among land cover, vegetation index, and nitrate concentrations in streams of the Enoree River Basin, piedmont region of South Carolina, USA

Abstract Globally, high nitrate concentrations and fluxes in rivers are correlated with human population density and can lead to eutrophication of estuaries and coastal oceans. Although elevated nitrate concentrations often are associated with agricultural land cover, urban land cover also can contribute substantially to elevated nitrate concentrations in streams and rivers. In the piedmont region of the southeastern United States, urban areas typically are located in the headwater areas of watersheds. Because headwaters account for the majority of stream channel length in a watershed, the effect of urbanization on the biogeochemical cycling of nitrogen is magnified. We examined the relations between stream nitrate concentrations, land cover, and vegetation density in watersheds of nineteen tributaries of the Enoree River in northwestern South Carolina, USA. Based on data from 134 sample localities, stream nitrate concentrations generally increased with increasing urban land cover and decreased with increasing forest cover and vegetation density (normalized density vegetation index). Although watersheds with the highest percent urban land cover typically had the highest nitrate concentrations, nitrate concentrations were most variable spatially in drainage basins with 5 to 20% urban land cover. The relations between land cover, vegetation density, and nitrate concentrations are complicated by variation in the intensity of urbanization and spatial location of urban and forested land within the drainage basin of each sample locality. Artificial ponds in urban areas appear to play an important role in lowering stream nitrate concentrations and contribute to the spatial variability of nitrate concentrations.

The Effect of an Industrial Spill on the Macrofauna of a South Carolina Stream: Physiological to Community-Level Responses

ABSTRACT In 1985, a waste retainment pond ruptured at a galvanizing facility and spilled 75,700 liters of HCl and other contaminants into the groundwater above the Upper Enoree River in South Carolina USA. In 1999, we examined the residual effects of this spill by surveying the water chemistry and biota in the main channel of the Upper Enoree River and uncontaminated tributaries. We also transplanted yellowfin shiners (Notropis lutipinnis) to channel and tributary sites and monitoring their survivorship and the histological condition of their gills. The two upstream sites were significantly different in chemical composition from downstream sites and control tributaries. Conductivity and the concentrations of Na+, K+, Ca2+, Mg2+, Cl−, NO3− , PO3− , F−, Zn2+, and Mn2+ were highest at the headwater site and declined significantly downstream. The abundance and diversity of salamanders, fish, and macroinvertebrates correlated with these changes in water chemistry. Yellowfin shiners (Notropis lutipinnis) transplanted to the headwater site died within 24 hours, and fish in channel sites had significantly higher mortality than fish transplanted to tributary sites. At the tissue level, the size and density of gill pavement cells were significantly lower in fish transplanted into the two headwater sites closest to the spill compared to other channel and tributary sites. Thus, this spill continues to exert a significant effect on the chemistry and biota of the Upper Enoree River.

Relationships between Dry Deposition of Ions and Urban Land Cover in the South Carolina Piedmont

Atmospheric deposition can be an important source of ions to terrestrial and aquatic ecosystems. Previous studies have indicated that dry deposition of ions in and near large cities is greater than in nearby rural areas. However, few studies have compared dry deposition in and near smaller cities. We measured dry deposition of ions at various distances from Greenville, a smaller city in the piedmont of northwestern South Carolina. Dry deposition was estimated by exposure of artificial surfaces (glass Petri plates and paper filters) to the atmosphere at 13 locations during June–July 2008. Petri plates were expected to collect dust particles primarily, whereas filters were expected to collect both dust and gases. Fluxes measured by filters were significantly greater than those measured by Petri plates for nitrate and ammonium, suggesting that dry deposition of nitrogen in gases exceeded dry deposition in dust. Dry deposition of ammonium and nitrate declined significantly with distance from Greenville, and rates were significantly higher at urban than at rural locations. Also, dry deposition rates of ammonium correlated positively with road densities and traffic volumes around sampling locations, suggesting that automobiles were important sources of ammonia gas. Relationships between ammonium deposition and urban land cover and roads were stronger than for nitrate deposition, perhaps reflecting the influence of automobiles using catalytic converters. Base cation concentrations in dry deposition typically were below detection, precluding flux calculations. Overall, our results provide evidence that smaller cities influence atmospheric deposition of nitrogen, though perhaps not as strongly as larger cities.

Hydrogeochemical Characterization of Headwater Seepages Inhabited by the Endangered Bunched Arrowhead (Sagittaria fasciculata) in the Upper Piedmont of South Carolina

Abstract Sagittaria fasciculata (Bunched Arrowhead) is an endangered plant known to grow only in Greenville County, SC, and Henderson and Buncombe counties, NC. This study compared the hydrogeochemical characteristics (hydrologic setting, water chemistry, substrate grain size, and organic matter content) of fourteen Bunched Arrowhead sites across Greenville County. All Bunched Arrowhead were found in partially to fully shaded and saturated discharge areas in close proximity to and fed by continuous and consistent groundwater seeps. The plants grew in sandy substrata with highly variable organic matter contents. Surface waters at these sites were shallow, dilute, and acidic (pH 4.5–5.7). However, the degree to which water chemistry influences the plants growth and survival remains to be determined.