The Green Mineral

For my summer research I will be directing my attention to a peculiar green mineral called Glauconite, which is iron-potassium rich and has been formed from chemically altered fecal pellets of aquatic creatures.
A limiting nutrient is scare in natural environments (without any human influence) and one that is necessary for the growth of organisms, plants, and animals. Nitrogen and phosphorous are limiting nutrients for freshwater ecosystems since aquatic plants feed off of those nutrients. With a low source of those nutrients available, the productivity of the lake will be low -- the plants serve as a food source for zooplankton and small fish which are then are meals for larger fish and so on. A high input of nutrients from soil runoff of agricultural fields and urban areas causes blooms to occur of microscopic plants and bacteria -- especially of cyanobacteria. Cyanophyta blooms are problematic for they interfere with water clarity, which prevents the penetration of sunlight to the lake bottom needed for aquatic plant growth. Additionally, oxygen is depleted from the increased decomposition of cyanobacteria causing fish kills. This is a widespread occurrence in many freshwater bodies including Lake Menomin and Lake Tainter.

My research question is if iron is a limiting nutrient in addition to nitrogen and phosphorous. The motivation behind this question comes from the predicted increase in storm frequency and strength due to global warming and the possible increase in erosion rates as a result. Glauconite is imbedded within the Lone, Mazomanic, and Eau Claire Rock Formations of the Red Cedar Basin and the mineral has a low resistance to weathering events, which can indicate increases iron input. One question I have additionally is what the abundance of Glauconite within the bedrock layers is and how much would be added to the waterways of the Red Cedar Basin with erosion.

From my studies, I hope to learn more about the various creative ways in which freshwater bodies such as Lake Menomin can be saved from hypereutrophication by reducing the runoff into waterways and the nutrient concentration within the water bodies. I am also very interested in what my co-interns will be researching, both of which I can learn about when I shadow my co-interns in the next week or so. Updates to come, stay tuned!!