October 1, 2017.
Water in the Sacramento-San Joaquin Delta has three main uses: it serves as a habitat for the fish, irrigation, and a small amount of the water is distributed to the city. The presence of water hyacinth and primrose, two invasive plants, kills fish by depleting the oxygen in the water, they also interfere with shipping and clog the water channels. Integrated Pest Management (IPM) strategies that include chemical, mechanical and bio-control have been used to eliminate water hyacinth and primrose at the delta. During this research, we obtained and analyzed pictures at the Delta and used their geospatial (longitude and latitude) information to calculate the presence of water hyacinth and primrose at different zones that were not chemically treated and other areas that were treated. Our analysis was object-based and we used ENVI software’s feature extraction tool to draw boundaries around the leaves of water hyacinth and primrose to segment the picture and create polygons. We used the polygons’s RGB (Red-Green-Blue) bands and their roundness to classify the polygons into six classes using ArcMap. Water hyacinth was seen in a lower percentage in our pictures because this year it rained more in the delta compared to 2015 and this allowed the plant to flow and be flushed out. An equation to calculate the velocity of the plant rafts can help to make predictions of the presence of water hyacinth at different sites in the Delta. This information will serve the economists to plan the mechanical and chemical efforts made to eradicate the plant. Our observations also confirm that the chemical treatments fulfill their purpose and water hyacinth is killed.
NASA Ames Research Center (ARC)
This material is based upon work supported by the National Science Foundation through the Robert Noyce Teacher Scholarship Program under Grant # 1340110. Any opinions, findings, and conclusions or recommendations expressed in this material are those of the author(s) and do not necessarily reflect the views of the National Science Foundation. The research was also made possible by the California State University STEM Teacher and Researcher Program, in partnership with Chevron (www.chevron.com), the National Marine Sanctuary Foundation (www.marinesanctuary.org) and NASA Ames Researcher Center.