Bachelor of Science (B.S.)
Science & Environmental Policy
he Elkhorn Slough watershed has experienced significant landuse change between 1937 to the present. The watershed is made up of seven landuse classifications: chaparral, grasslands, marshland, oak woodland, riparian, agriculture and non-vegetated (urban). Using 1937 aerial photos as a study site I have found that landuse has changed by 1%, 7%, 0%, 4%, 0%, -7%, -4% respectively where the negative values indicate an increase in landuse. The study site covers 3,978 of a 13,142 ha watershed, which represents about 30% of the watershed. This was determined by using GIS processes to find the area of landuse in 1937 and what the current landuse is. The landuse change analysis was used to estimate annual runoff coming from four of the ecosystems: oak woodlands, chaparral, grasslands, and agriculture by using the Biogeochemical cycles (BGC) model and the runoff rational method. The results for the BGC model/runoff rational method as of now are inconclusive. More research needs to be done to validate the numbers presented in this paper. What was shown was that the BGC runoff and the runoff rational method, estimations of average annual runoff increased when landuse changed from native to agriculture. This suggests an inverse relationship between landcover and runoff.
Oberbauer, Brandon, "Analysis of runoff in the Elkhorn Slough Watershed as a result of land-use change using the BGC model, runoff rational method and GIS" (1999). Capstone Projects and Master's Theses. 162.