摘要:

In 1987, lime (250 mg/L calcium carbonate or 250 mg/L calcium hydroxide) was added to four hardwater dugouts in northwestern Alberta to precipitate the phosphorus and algae and improve water quality. Calcium carbonate reduced algal biomass to 39 percent of pretreatment concentrations between June and August of 1987, but dugouts recovered to pretreatment concentrations during the next summer. Calcium hydroxide treatments reduced algal biomass to 12 percent of pretreatment concentrations and dugouts remained at that level over the following summer. Phosphorus concentrations were decreased by 80 percent in calcium hydroxide-treated dugouts but were relatively constant in calcium carbonate-treated dugouts. Calcium hydroxide treatments can improve water quality in dugouts for a chemical cost of $200–$400.

ISSN:1040-2381    

DOI:10.1080/07438149009354700

出版商:Taylor & Francis Group    

年代:1990

数据来源: Taylor

摘要:

Lake management often requires assessment of water quality impacts on lake users. Lake user surveys provide a means for linking sampling parameters such as total phosphorus, chlorophylla, or transparency and user impacts such as nuisance algae levels and recreational impairment. A lake user survey was conducted on nearly 500 lakes in Minnesota and Vermont concurrently with citizens' water quality sampling programs. The results showed that quantifiable and statistically significant relationships existed between eutrophication-related water quality measurements and user perceptions of nuisance algal conditions. However, strong differences existed in these relationships between the two states and among lake regions within each state, indicating that specific regional relationships should be developed whenever possible. This report describes applications of lake user survey results, including statewide lake assessments, wastewater discharge impact evaluations, lake management goal setting, and water quality standards development.

ISSN:1040-2381    

DOI:10.1080/07438149009354701

出版商:Taylor & Francis Group    

年代:1990

数据来源: Taylor