University of Rhode Island
The Santa Maria River spans approximately 148 kilometers from its headwaters in the district of Santa Fe, Veraguas to its mouth at the Golfo de Parita, Herrera. The objective of this study was to determine the relation between land-use and site-specific water quality using benthic macroinvertebrates as indicators. To assess water quality of the upper portion of the Santa Maria River, benthic macroinvertebrates were collected at 10 points within the river from Santa Fe national park to the town of San Francisco, approximately 62.8 kilometers. This study examines how land-use near the banks of the Santa Maria River effect water quality, taking into consideration both point and non-point sources of pollution within the watershed. Sample areas encompassed a variety of land-uses throughout the watershed. Water quality was assessed at each sample site by measuring dissolved oxygen levels, pH, river flow, percent canopy cover, and water temperature. Benthic macroinvertebrates were collected using a 250-μm mesh D-Frame kicknet in 3 riffle habitats per site and identified and ranked based on pollution tolerance using the EPT index. The site-specific water quality was determined for each location and assessed based on the primary land-use within the immediate area around each river sample site. The water quality at each point was ranked as either very good, good, intermediate, or disturbed according to the EPT index and the benthic macroinvertebrates collected. Land-use and land-cover percentages of the surrounding area of the river were evaluated using geospatial data and direct observation. Generally, percent forest cover decreased with distance from Santa Fe and the area surrounding San Francisco was primarily cattle ranches and farms. It was observed that water quality decreased as distance from Santa Fe increased and as elevation decreased. The analysis of sample site water quality values ranked this portion of the Santa Maria River as good water quality overall, however, some of the sites further downstream near ranches and farms were ranked as disturbed. Therefore, this study supports evidence that the variety of water quality rankings of the upper portion of the Santa Maria River from Santa Fe to San Francisco are dependent on primary land-use of the area surrounding the river.
Environmental Indicators and Impact Assessment | Environmental Sciences | Water Resource Management
Steeves, Charlotte, "Water Quality in Relation to Land-use of the upper 62.8 Kilometers of the Santa Maria River, Santa Fe, Veraguas Using Benthic Macroinvertebrates as Indicators" (2016). Independent Study Project (ISP) Collection. 2389.