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Full-Text Articles in Earth Sciences
Water Quality In Southeastern Minnesota Streams: Observations Along A Gradient Of Land Use And Geology, Nels H. Troelstrup Jr., James A. Perry
Water Quality In Southeastern Minnesota Streams: Observations Along A Gradient Of Land Use And Geology, Nels H. Troelstrup Jr., James A. Perry
Journal of the Minnesota Academy of Science
ABSTRACT-Surface water quality in southeastern Minnesota's driftless area exhibits subregional and local spatial patterns which are highly correlated with subsurface geology and land-use practices. Some variables appear to respond on subregional or watershed scales. Nitrate, specific conductance, alkalinity, and surface water atrazine concentrations were lower in streams originating from the Prairie Du Chien or Jordan sandstone ~quifers of easte:n Fillmore and Houston Counties than those originating from the Galena limestone aquifer m west-central Fillmore County. In addition, the numbers of pollution intolerant and functionally specialized invertebrates in the benthic community were higher in the eastern streams. Gross primary production on …
Nitrogen Management Related To Groundwater Quality In Minnesota, James L. Anderson, Gary L. Malzer, Gyles W. Randall, George W. Rehm
Nitrogen Management Related To Groundwater Quality In Minnesota, James L. Anderson, Gary L. Malzer, Gyles W. Randall, George W. Rehm
Journal of the Minnesota Academy of Science
ABSTRACT-Minnesota ranks fifth in overall fertilizer nitrogen (FN) use. Nitrogen is essential for crop production; however, there are concerns about this use relative to profitability and potential impacts on groundwater. There are many sources and sinks of nitrogen in ecosystems. The impact of agricultural management practices on groundwater requires that all sources and fates be considered before FN rates are determined. Research is underway to evaluate relationships between FN application for continuous com and movement of nitrate through soil profiles. Growers making N management decisions have to be able to evaluate the complex nature of N in the environment when …
The Water Quality And Management Of Lakes In The Twin Cities Metropolitan Area, Richard A. Osgood, Gary L. Oberts
The Water Quality And Management Of Lakes In The Twin Cities Metropolitan Area, Richard A. Osgood, Gary L. Oberts
Journal of the Minnesota Academy of Science
ABSTRACT-We have detected a slow degradation in the water quality of Twin Cities Metropolitan Area lakes du~ to phospho_rus enrichment. While the water quality of the lakes does not appear to limit most uses, nmsances do exist. We have further discovered that commonly-used watershed treatments such as wetland diversions and ponding, are ineffective ~t reversing or completely mitigating the degradati~n following land development. Th_erefore, we are su~gestmg that lake managers reduce the external loading of phosphorus to the greatest ~oss_1ble extent; then, 1f further water quality improvements are necessary, that measures which treat eutroph1cat1on-related symptoms be considered for the long-term …
Lake Mixing Dynamics And Water Quality Models, Heinz G. Stefan
Lake Mixing Dynamics And Water Quality Models, Heinz G. Stefan
Journal of the Minnesota Academy of Science
ABSTRACT-To forecast water quality changes or to evaluate the potential success of restoration measures in lakes, it is necessary to formulate "models" which relate lake water quality to the inflows and outflows of materials and energy. Concepts of dynamic deterministic (cause-effect) models and examples are presented. The relationship between internal thermo-hydraulic processes and water quality is stressed. Stratification mixing, and nutrient kinetics are included in these models.
Viruses And Drug Resistant Bacteria In Groundwater Of Southeastern Minnesota, Sagar M. Goyal, Daniel Amundson, Robert A. Robinson, Charles P. Gerba
Viruses And Drug Resistant Bacteria In Groundwater Of Southeastern Minnesota, Sagar M. Goyal, Daniel Amundson, Robert A. Robinson, Charles P. Gerba
Journal of the Minnesota Academy of Science
ABSTRACT-Karst topography of soils in southeastern Minnesota is responsible for the formation of sinkholes, subsurface cracks, and underground rivers which may enhance the transportation of surface contaminants into groundwater. The present study was conducted to determine the presence of human pathogenic viruses, coliforms, fecal coliforms and coliphages in private rural wells of this area. The occurrence of drug resistance in bacteria isolated from groundwater also was studied. Coliform bacteria were detected at least once from 22 of the 26 sites sampled over 34 months. Water from 10 sites yielded drug-resistant indicator bacteria; 25 of 38 (65.8 percent) total coliforms and …
The Regional Nature Of Lake Water Quality Across Minnesota: An Analysis For Improving Resource Management, Steven A. Heiskary, C. Bruce Wilson
The Regional Nature Of Lake Water Quality Across Minnesota: An Analysis For Improving Resource Management, Steven A. Heiskary, C. Bruce Wilson
Journal of the Minnesota Academy of Science
ABSTRACT-The diversity and number of lakes in Minnesota may be better understood by the use of regional characterizations of lake and watershed information. Recent efforts have utilized the ecoregion approach to define seven regions across Minnesota, four of which contain 98 percent of our lake resources. Typical land use patterns vary regionally as do lake water quality patterns. Understanding these patterns will assist lake managers to develop realistic goals and minimize false expectations. Regional assessments facilitate the definition of reasonable goals, expressed in terms of: average summer nutrient concentrations, probability of nuisance conditions ( e.g., estimates of algal bloom frequency), …
The Legislative Commission On Minnesota Resources Involvement In Water Resource Programs, John Velin, George Orning
The Legislative Commission On Minnesota Resources Involvement In Water Resource Programs, John Velin, George Orning
Journal of the Minnesota Academy of Science
ABSTRACT :--The Legislative Commission on Minnesota Resources (LCMR) has funded over $32 million worth of projects m three water-related areas since 1963. The authors describe the process the Commission uses to allocate money and summarize the general nature and accomplishments of many of the water projects.