Effects of golf course facilities on stream function in anthropogenically impacted streams

We sampled six streams in southern Ontario, Canada near 18-hole golf courses to determine how they affect stream function in the context of land use, land cover, and human activities in the upstream watershed. Water quality, optical dissolved organic matter (DOM), and benthic characteristics (e.g., leaf decomposition, ergosterol content, and N2 and O2 flux) were followed up and downstream of the golf courses over a three-week period in summer. Comparisons of univariate paired samples revealed lower dissolved organic carbon concentrations and higher total dissolved phosphorus concentrations, with relative losses in humic-like and gains in protein-like DOM downstream of golf courses. Total dissolved nitrogen and bacterial production were similar up and downstream of golf courses. Multivariate analysis indicated that streams did not significantly differ up and downstream of golf courses for landscape, water quality, and DOM groups, but significantly differed among streams. A significant multivariate benthic group interaction between stream and sampling location indicated, however, that the magnitude and the direction of change exerted by the golf course differed across streams. Streams did not change, lose, or recover benthic functionality after passing through a golf course. This response depended on the percent anthropogenic land use in the watershed's riparian zone and was not simply a uniform environmental response to golf course facilities. These findings show promise that in moderately human impacted streams golf course facilities could be managed to improve stream function. In severely human impacted streams, however, landscape management strategies that use golf courses as green spaces will unlikely improve stream function.