You have entered the website of the Water and Environmental Research Institute of the Western Pacific (WERI) at the University of Guam. We are currently six faculty and five staff and our mission is to seek solutions through research, teaching and outreach programs, to issues and problems associated with the location, production, distribution and management of freshwater resources in Guam, the CNMI and the FSM.
An investigation of the nitrogen-fixing, blue-green alga Nostoc muscorum Ag. as a possible contributor of nitrate to the groundwater of Guam was carried out from October 1977 to January 1979. Total potential nitrate contribution was determined by combining data obtained for ammonia excretion (a maximum of 1.39 μg/NH4/g Nostoc/hr), percent nitrogen (3.38%), and growth rates (40% increase per week) with algal biomass estimates for Guam (2.6 x 106 kg) to obtain a value of 1.3 μg NO3-N/mL rainwater. Soil percolate studies were similarly extrapolated to produce a corresponding value of 6.5 x 10-4 ug NO3-N/mL rainwater. Both values are well below those obtained from the groundwater, i.e., 2μg NO3-N/mL. It is concluded that Nostoc muscorum does not contribute significantly to the high nitrate content of Guam’s groundwater.
