- cups filled with agar and nutrients
Hello, this is Maria Neidhardt. I am a rising junior studying environmental science technology and policy at the California State University Monterey Bay in Seaside, California. This summer I will be working with Dr. Denise Bruesewitz. For our project, we will be looking at nitrogen (N) and phosphorous (P) levels in the Copano Bay and the Mission and Aransas rivers that feed into the bay. Our research will help us to shed some light on the question: How much nutrients (especially N) can be added to this area before major problems like eutrophication and hypoxia occur? Eutrophication can occur when there is an excess of one nutrient, typically N or P. As more and more people utilize an area they can add excess nutrients to the water, having great environmental such as hypoxia, or very low levels of oxygen in the water. In order to address our question, we will be filling small plastic cups called ‘nutrient diffusing substrates’ with agar and different combinations of N and P (NO3, NO3+P, NH4, NH4+P, and P) and placing them in sites along the Mission and Aransas Rivers and at the mouth of the bay. Each cup is outfitted with either a glass disc or a cellulose sponge to select for algal and heterotrophic bacterial communities, respectively. After placing our nutrient diffusing substrates in the rivers we will collect the bacteria and algae growing on them in an attempt to see which nutrients are in higher demand by the algae and bacteria. We will measure gross primary production and respiration by algal and bacterial communities on our different treatments. Conducting our experiment at multiple sites in the rivers and bay will allow us to get a variety of different results, since we expect that different parts of the river-bay continuum have different nutrient limitations.