Figure 1

Predicted total mercury concentrations based on fish tissue samples*. Spatial interpolation of total mercury concentrations in South Carolina largemouth bass (1995–2005, N = 3,828 samples) obtained via ordinary kriging with the following model specifications: a U-shaped trend was modeled via a second-order polynomial; the semivariogram was fitted with an exponential model; anisotropy was assigned from northwest to southeast following the flow of water in SC; the searching neighborhood was defined as a directional ellipse with four sectors (100 neighbors per sector, minimum = 5). Gray areas correspond to southern coastal plain; there are no largemouth bass in these areas.