Project Research Results
Grantee Research Project Results
2003 Progress Report: Adaptive Management for Improved Water Quality in Multi-Use WatershedsEPA Grant Number: CR830653
Title: Adaptive Management for Improved Water Quality in Multi-Use Watersheds
Investigators: Lehman, John
Institution: University of Michigan
EPA Project Officer: Sergeant, Anne
Project Period: January 1, 2003 through January 1, 2006 (Extended to January 31, 2007)
Project Period Covered by this Report: January 1, 2003 through January 1, 2004
Project Amount: $745,883
RFA: Nutrient Science for Improved Watershed Management (2002)
Research Category: Water and Watersheds
The objectives of this research project are to: (1) identify sources and sinks of nitrogen, phosphorus, silicon, and biologically important trace metals through a heterogeneous watershed containing multiple impoundments; (2) measure transformation rates of nutrient elements, biological availability, anaerobic metabolism, biomass production, and community composition; (3) identify potential modes of intervention that could ameliorate nuisance algae conditions; and (4) communicate findings and recommendations to municipal and state officials, citizen advisory commissions, and environmental advocacy groups. The research project is focused on the Huron River of southeastern Michigan, but results are generalizable on a regional and national scale.Progress Summary:
Although the grant was awarded in February 2003, funding was not available until May and field work commenced in June 2003; therefore, the progress described in this report was for the period June 1, 2003 to June 30, 2004. Eleven sampling stations were established along the middle reach of the Huron River and six additional sites were established in three of the major impoundments, including one used for drinking water and two that have been notorious for nuisance cyanobacterial blooms. Sampling frequency has ranged from 3- and 4-day intervals during the summer to 2-week intervals during ice and snow cover during the winter. Automated instruments also are deployed in the lakes during the summer.
Routine measurements from field-collected river samples include pH, specific conductance, ammonium, nitrate, total dissolved nitrogen, particulate nitrogen, soluble reactive phosphorus, total dissolved phosphorus, total phosphorus, soluble reactive silicon, major cations, arsenic, aluminum, manganese, iron, copper, zinc, molybdenum, and lead. Lake sampling includes an additional vertical profile structure for temperature, oxygen, pH, light attenuation, in vivo fluorescence (chlorophyll), and turbidity. Laboratory assays include assays for chlorophyll a, phycocyanin, diatom silicon, and alkaline phosphatase activity.
Various experiments have been conducted to evaluate nutrient conditions and growth potentials of water from different sources. These experiments have examined: (1) phosphate uptake kinetics; (2) rates of uptake of nitrate and ammonium; (3) rates of oxygen consumption; (4) rates of nitrification; (5) rates of nitrogen fixation; (6) growth potential by both native and cultured algae; (7) effects of zooplankton grazing; and (8) types of nutrient limitation judged by nutrient addition bioassays. The experiments also have been used to ascertain the stoichiometries among nitrogen, phosphorus, silicon, and chlorophyll during periods of algal growth.
The years 2003 and 2004 have been strikingly different in weather and hydrology, with major consequences for lake community dynamics, nutrient fluxes, and algal bloom developments. River discharge during the summer of 2003 was at the lowest 10th percentile, as indicated by historical records from the last 20 years. In contrast, 2004 is among the coolest and wettest of recent record; daily river discharges on May 22 and 23, 2004, were the 9th and 14th highest discharges of the last 20 years, and the only ones not associated with snowmelts during winter. As a consequence, differences emerged between years in terms of vertical stratification, oxygen depletion, denitrification, nitrogen depletion of surface water, metal concentrations, and algal community dynamics.
Mass balance models for nitrogen and phosphorus have been constructed and are updated continually. The results reveal greater differential loss of nitrogen with respect to phosphorus in the impoundments in 2003 compared with 2004. This appears to coincide with excess nitrate consumption and phosphate regeneration during periods of anoxia. Although Aphanizomenon developed large biomass in 2004, warm stagnant conditions conducive to concentrations at the surface rarely developed; hence, the putrid mats of recent past years did not materialize.
All of the impoundments exhibit diatom blooms in the spring, which deplete silica virtually to zero in the most nutrient-enriched basins. The diatom bloom is followed by a clear water phase associated with large Daphnia. Then, cyanobacterial populations emerge even though silica recovers to high levels. Nutrient bioassay experiments have demonstrated that the diatoms are differentially limited by iron at this time, and the dissolved iron levels are severely depressed.
Partnerships and Communications
We established lines of communication and collaboration with the various municipalities and agencies that have jurisdiction over the watershed segments, impoundments, and hydroelectric dams that comprise our study region. In addition to meetings with municipal and regional boards, commissions, and councils, the research project has received feature attention in regional news media and National Public Radio interviews cited below.Future Activities:
With the advent of mass balance models for the River by segment and impoundment, we identified sink and source regions for nutrient elements. We will be working with existing geographic information system-based land use and digital elevation models to characterize loadings more specifically, and to possibly recommend control strategies.
The main sampling effort will continue, with particular attention toward the interaction between hydrology and environmental conditions. We also will examine further the competitive interface between diatoms and bluegreens, including the potential for trace metal limitations.
During the fall of 2004, we will explore the prospect of performing hypolimnetic oxygen manipulation by hyperbaric injection during the summer of 2005, if anoxic conditions develop. This large-scale experiment will involve discussions with municipal officials and citizen advisory groups, as well as an engineering firm that is volunteering an innovative technology.Journal Articles:
No journal articles submitted with this report: View all 15 publications for this projectSupplemental Keywords:
water, drinking water, watersheds, soil, sediments, adsorption, absorption, chemical transport, ecological effects, bioavailability, metabolism, organism, cellular, population, enzymes, stressor, chemicals, toxics, particulates, metals, heavy metals, effluent, discharge, dissolved solids, ecosystem, indicators, restoration, regionalization, scaling, terrestrial, aquatic, habitat, integrated assessment, innovative technology, remediation, oxidation, public policy, decisionmaking, community-based, cost benefit, survey, preferences, environmental assets, environmental chemistry, biology, physics, mathematics, ecology, hydrology, geology, limnology, zoology, modeling, monitoring, analytical, surveys, measurement methods, remote sensing, Great Lakes, Midwest, Michigan, MI, Huron River, Barton Pond, Ford Lake, Belleville Lake, Secchi depth, nutrient flux, watershed assessment, watershed management, watershed restoration, anaerobic nitrate respiration,, RFA, Scientific Discipline, INTERNATIONAL COOPERATION, Water, ECOSYSTEMS, Ecosystem Protection/Environmental Exposure & Risk, POLLUTANTS/TOXICS, Aquatic Ecosystems & Estuarine Research, Water & Watershed, Arsenic, Aquatic Ecosystem, Water Quality Monitoring, algal blooms, Environmental Monitoring, Terrestrial Ecosystems, Ecology and Ecosystems, Water Pollutants, Watersheds, anthropogenic processes, anthropogenic stress, bioassessment, biodiversity, bloom dynamics, watershed management, ecosystem monitoring, conservation, nutrient kinetics, biota diversity, diagnostic indicators, ecosystem indicators, redox chemistry, aquatic ecosystems, water quality, bioindicators, watershed sustainablility, dissolved organic nitrogen, biological indicators, ecosystem stress, watershed assessment, conservation planning, aquatic biota, nitrogen, restoration planning, watershed restoration