Seasonal physicochemical characteristics of thirty northern Ohio temporary pools along gradients of GIS-delineated human land-use

Abstract

Human development pollutes runoff and ground water. Temporary pools are good habitats to study the influence of general non-point source pollution because they are created by runoff and ground water, among other processes, which, in northern Ohio, can contain substances accumulated over the winter. Furthermore, little information on land-use effects on temporary pools exists. To ascertain if general human activities influenced the water quality of northern Ohio temporary pools, monthly measurements of pH, dissolved oxygen, temperature, conductivity, and depth were monitored from March–June 2004 in 30 dispersed pools of the Cuyahoga River basin, Ohio, USA. Nutrient measurements for most pools were taken in May and June 2004. Pools were located in ten sub-watersheds containing differing percentages of geographic information system (GIS)-delineated urban/suburban and agricultural lands. General water quality characteristics of northern Ohio temporary pools were variable, both spatially and temporally. Nutrient levels were generally low (oligotrophic). Spearman rank correlation coefficients between the characteristics and percent land-use showed that conductivity and percent agriculture were positively correlated, while depth and percent urban were negatively correlated. Temporally, dissolved oxygen and depth showed fairly strong seasonal decreases from March–June. Some measurements from pools in mostly natural sub-watersheds suggested poor water quality. Although large-scale (watershed) land-use influences can affect the physicochemical nature of temporary pools, local anthropogenic influences, both past and present, probably also affect the quality of temporary pool wetlands.