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1	Factors affecting nitrogen transformations in grazed grassland soils with specific reference to the effects of artificial land drainage and N-fertilization Blantern, Paul Jonathan January 1991 (has links) No description available. 631.4 Soil nitrogen content
2	Bromegrass Productivity in Relation to Precipitation, Shrub Canopy Cover and Soil Nitrogen Content Kline, Lawrence G. 01 May 1973 (has links) In seasons of above normal precipitation, populations of annual weedy species increase in great abundance in semi-arid desert plant communities. These increases in biomass tie up a considerable portion of the available nitrogen of such ecosystems and may depress subsequent annual grass germination. A big sagebrush-annual bromegrass plant community was irrigated to simulate a spring growth period of abundant precipitation amenable to annual bromegras s productivity. Productivity and nitrogen content parameters were monitored throughout the spring and summer to evaluate the short and potential long term effects of this seasonal increase in "precipitation". Irrigation increased annual bromegrass productivity almost 50 percent. This increase was a result of the combined factors of increased soil moisture content and increased nitrogen availability due, apparently, to increased soil microfloral nitrification activity under low water water stress conditions. The increased annual growth resulted in a greater nitrogen uptake despite an observed decrease in irrigated bromegrass percent nitrogen values. Both the tie up and irrigation effect were maintained throughout the summer and into the subsequent annual germination period. However, total soil nitrogen levels and bromegrass nitrogen mineralization rates suggest that soil nutrient conditions for subsequently germinating bromegrass seedlings do not differ because of previous spring irrigation treatment. bromegrass productivity precipitation shrub canopy cover soil nitrogen content Ecology and Evolutionary Biology Environmental Sciences Plant Sciences Soil Science
3	Behavioral and ecological consequences of multiple intraguild predators and connections between predators, prey, and ecosystem function Sitvarin, Michael Ian 25 August 2014 (has links) No description available. Biology Ecology Entomology Organismal Biology Soil Sciences Zoology predation ecology behavior predator prey nonconsumptive effects intraguild predation emergent multiple predator effects activity survival ecosystem function soil respiration soil nitrogen content trait-mediated interaction interference

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