خيارات البحث
النتائج 31 - 40 من 101
Waste wool as a scavenger for mercury pollution in waters
1972
Tratnyek, Joseph P.
[Papers]
1972
Murphy, R. Sage | Nyquist, David
The effects of artificial aeration on lake ecology
1972
Fast, Arlo W.
Hypochlorite generator for treatment of combined sewer overflows
1972
Leitz, F. B. | Michalek, Steven A. | Greatorex, J. L.
The Economic impact of pollution control
1972
Filtration of municipal waste with a moving bed contactor
1972
Mixon, F. O.
Erosion and sediment pollution control
1972
Beasley, R. P. (Robert Patrick)
Trickling filter treatment of fruit processing waste waters
1972
Rose, Walter W. | Mercer, Walter A.
Role of bacteria in the nitrogen cycle in lakes
1972
McCoy, Elizabeth
Biological nitrification as contributing nitrite and nitrate to lakes and streams was explored by determining: nitrifiers, growth sites and activity; denitrifying bacteria numbers and their potential activity as opposing nitrification; field data on nitrite-nitrogen and nitrate-nitrogen in terms of nitrifier and denitrifier populations. Biological nitrification, both heterotrophic and autotrophic, was demonstrated. Even though opposing processes, nitrification and denitrification can coexist in close succession or in adjoining microhabitats. Field values for nitrate-nitrogen and nitrite-nitrogen vary considerably and must be viewed as net values at any given time. Thirteen species of fishes varied greatly in resistance to nitrite-nitrogen. Nitrite toxicity may influence fish species dominance in a eutrophic lake.
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