Open Access. Powered by Scholars. Published by Universities.®
Physical Sciences and Mathematics Commons™
Open Access. Powered by Scholars. Published by Universities.®
Articles 1 - 2 of 2
Full-Text Articles in Physical Sciences and Mathematics
A Bat-Guano-Derived Δ15N And Δ13C Record Of Paleoenvironmental Change: Zidită Cave, Romania, Daniel Martin Cleary
A Bat-Guano-Derived Δ15N And Δ13C Record Of Paleoenvironmental Change: Zidită Cave, Romania, Daniel Martin Cleary
USF Tampa Graduate Theses and Dissertations
Because nitrogen isotopes are fractionated along the soil-plant-insect-bat-guano pathway, it may be possible to reconstruct environmental and climatic changes reflected in the nitrogen isotopic composition of guano. A 1.5-m core of bat guano from Zidită Cave (western Romania) provides a record of climatic and anthropogenic influence on the regional nitrogen cycle and paleoenvironmental controls on nitrogen transforming processes. Increasing and decreasing trends of nitrogen isotopic composition (δ15N values) correspond well with changes in the influence of farming practices, deforestation, and forest expansion. These influences likely had a significant effect on the openness of the nitrogen cycle, resulting in …
At-Grade Stabilization Structure Impact On Surface Water Quality Of An Agricultural Watershed, Kyle R. Minks, Matthew D. Ruark, Birl Lowery, Fred W. Madison, Dennis Frame, Todd D. Stuntebeck, Matthew J. Komiskey, George J. Kraft
At-Grade Stabilization Structure Impact On Surface Water Quality Of An Agricultural Watershed, Kyle R. Minks, Matthew D. Ruark, Birl Lowery, Fred W. Madison, Dennis Frame, Todd D. Stuntebeck, Matthew J. Komiskey, George J. Kraft
United States Geological Survey: Staff Publications
Decades of farming and fertilization of farm land in the unglaciated/Driftless Area (DA) of southwestern Wisconsin have resulted in the build-up of P and to some extent, N, in soils. This build-up, combined with steep topography and upper and lower elevation farming (tiered farming), exacerbates problems associated with runoff and nutrient transport in these landscapes. Use of an at-grade stabilization structure (AGSS) as an additional conservation practice to contour strip cropping and no-tillage, proved to be successful in reducing organic and sediment bound N and P within an agricultural watershed located in the DA. The research site was designed as …