Cohort Level: Cohort - IV

Career Goal: Get a job in scientific research, preferably in a field work type job.

Expected Graduation Date: May 20, 2022

Degree: M.S Geography

Research Title: Developing a sediment budget and understanding sediment accumulation in the Tijuana Estuary.

Research Synopsis: Coastal salt marshes have many environmental services that they provide to their surrounding ecosystems. One of the largest salt marshes in Southern California is the Tijuana Estuary. This estuary has come under threat from increased sediment accumulation. In order to maintain and develop regulations that can preserve this valuable ecosystem, a sediment budget must be produced. A sediment budget will allow the policy makers and researchers alike to gain an understanding of sediment input, output, and retention in the estuary. In addition, sediment accumulation will be studied to quantify patterns in sediment deposition throughout the estuary, to highlight areas with the greatest accumulation and the greatest need for mitigation/intervention.

Land cover and its dynamics over time are critical to models of human impacts on coastal ecosystems. In American Samoa, land-based sources of pollution (LBSP) have harmed coral ecosystems, but there is only land cover data for one year (2010) for American Samoa, and there is an urgent need to detect change over time and to map current land cover conditions in watersheds that drain directly to impacted reefs. This project will use time series of Landsat and Planet data to 1) detect changes in land cover in American Samoa and 2) create an updated map of land cover based on high-resolution imagery. Code will be developed in Google Earth Engine to identify and classify trajectories of NDVI over American Samoa. An existing 2010 land cover map will be used to develop rules for classifying land use, based first on NDVI, then on other bands as needed to create a final updated land cover map with acceptable accuracy. The maps will be summarized both by creating maps of change, and by quantifying change in land cover over time in watersheds draining to impacted reefs (Vatia, Fagaalu, and Nuuli).