Physical Sciences and Mathematics Commons^™

A Perspective On Economic Impact, L. Douglas James, Donald M. Soule, William O. Thompson, John L. Fulmer, John C. Redman, Robert C. Tussey, John M. Higgins, Claude M. Vaughan, David H. Rosenbaum, Billy R. Prebble, Charles O. Dowell, John E. Sirles, Michael B. Hargrove, Clyde T. Bates, Kenneth G. Holbrook, Dennis H. Bianchi, John P. Breaden, Kenneth R. Harman

KWRRI Research Reports

The institutions responsible for water resources management in the United States have originated as political responses to major social issues. Each agency institutionalized a procedure for structuring and comparing alternatives in the formulation of its total program. Each agency originally sought to promote effective resolution of its social issue (flood control, development of arid lands, soil erosion, etc.), but more recent efforts have sought better coordination among agency practices through a common procedure largely derived from economic theory. Any procedure, however, varies in application with the interpretation and judgment of individual planners. Today, public pressures have brought political directives requiring …

Degradation Of Riparian Leaves And The Recycling Of Nutrients In A Stream Ecosystem, Louis A. Krumholz, Roger G. Lambert, Charles R. Liston, Harry H. Woodward

KWRRI Research Reports

Leaves collected at 4 stations in the upper 5 km of Doe Run, Meade County, Kentucky, indicated an annual accumulation within the stream of 354 g/m²/year (17,700 kg). Leaves of sycamore (23.6%), red oak (21.7%), sugar maple (9.7%), beech (9.6%), white oak (7.1%), and hickory (6.0%) trees were most abundant, and leaves from 14 other kinds made up the remaining 22.3%. About a third of the annual leaf fall occurred during the last half of October and about two-thirds in the last 3 months of the year.

Calorific equivalents for different kinds of leaves ranged from 3,789 cal/g …

Factors Regulating The Growth Of Algae In Continuous Culture In Diluted Secondary Sewage Treatment Plant Effluent And Subsequent Biodegradability, Edward G. Foree, Caroline P. Wade

KWRRI Research Reports

Heterogeneous algal cultures were grown in laboratory continuous culture in continuous flow, completely mixed chemostats in secondary sewage treatment plant effluent diluted to give an ammonia nitrogen concentration of 10 mg/1. Variables were lighting, pH, carbon dioxide availability, and hydraulic residence time.

Optimum growth occurred under pH 7.0, excess CO₂, and continuous lighting conditions. The availability of artificially supplied excess CO₂ greatly increased the mass (standing crop) at steady-state over that produced under otherwise identical conditions for all residence times studied. For the case of excess CO₂ availability, the nitrogen concentration in the algal cells regulated …