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University of Georgia (2002)

The effects on water quality of restricting cattle access to a Georgia Piedmont stream

Thomas Zachary P

Titre : The effects on water quality of restricting cattle access to a Georgia Piedmont stream

Auteur : Thomas Zachary P

Université de soutenance : University of Georgia

Grade : Master of Science 2002

Résumé
Past research on the benefits of excluding cattle from streams has mostly been conducted in the western U.S. in arid regions with low grazing intensity (usually <1 AUM ha -1 ). This study was conducted on a Georgia Piedmont stream bisecting an intensively grazed dairy pasture (4 to 7.5 AUM ha -1 ). Nutrients, fecal coliforms, and the aquatic insect community were sampled before and after fencing was installed to restrict stream access. Restricting access resulted in decreases in nutrients (17 to 72%, p<0.05) and fecal coliforms (95%, p<0.1) and an increase in aquatic insect diversity. Coincident with fencing installation was cessation of a severe drought that caused an increase in nutrients (67 to 214%) and fecal coliforms (18%) and a decrease in aquatic insect diversity at an upstream reference site. Opposite trends at the study site suggest the effects of cattle access to streams outweigh those of severe drought.

Mots-clés : Water Quality ; Fencing Effects ; Cattle Grazing ; Fecal Coliforms ; Agricultural Pollution ; Nutrients ; Phosphorus ; Drought

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Page publiée le 27 avril 2011, mise à jour le 11 septembre 2018