Paper No. JAWRA-11-0082-P of the Journal of the American Water Resources Association (JAWRA). Discussions are open until six months from print publication.
Water Quality and Land Use Changes in the Alafia and Hillsborough River Watersheds, Florida, USA1
Version of Record online: 7 SEP 2012
© 2012 American Water Resources Association
JAWRA Journal of the American Water Resources Association
Volume 48, Issue 6, pages 1276–1293, December 2012
How to Cite
Khare, Y. P., Martinez, C. J. and Toor, G. S. (2012), Water Quality and Land Use Changes in the Alafia and Hillsborough River Watersheds, Florida, USA. JAWRA Journal of the American Water Resources Association, 48: 1276–1293. doi: 10.1111/j.1752-1688.2012.00686.x
- Issue online: 3 DEC 2012
- Version of Record online: 7 SEP 2012
- Received June 28, 2011; accepted July 25, 2012.
- water quality;
- land use;
Abstract: Spatial distribution of land use can have a substantial effect on surface and groundwater quality. Our objective was to test for trends in flow components and water quality related to changes in land use in the Alafia and Hillsborough River watersheds in Florida, USA, over the period 1974-2007. In addition, water quality statistics were evaluated in the perspective of numeric water quality criteria and proposed reclassification of segments of the Alafia River. Trends in 10 water quality parameters and three discharge variables were evaluated using a nonparametric trend detection test. Results of land use analysis indicated substantial urbanization and loss of agricultural land in the study area. Discharge variables did not exhibit significant trends, whereas trends in the majority of water quality concentrations were negative or nonsignificant with total nitrogen and total Kjeldahl nitrogen as exceptions showing positive trends. Changes in nutrient pathways could not be clearly identified. Considering recently promulgated numeric nutrient criteria and standards for dissolved fluoride, much of the Alafia River was found to be out of compliance. While there were land use changes and changes in water quality over the study period, it was difficult to identify a direct cause-effect relationship. Responses to regulatory efforts, such as the Clean Water Act and improvements in phosphate mining practices, may have had greater impacts on water quality than changes in land use.