Open Access. Powered by Scholars. Published by Universities.®

Digital Commons Network

Open Access. Powered by Scholars. Published by Universities.®

Articles 1 - 8 of 8

Full-Text Articles in Entire DC Network

Deep-Water Antipatharians: Proxies Of Environmental Change, B. Williams, M.J. Risk, S.W. Ross, K.J. Sulak Sep 2006

Deep-Water Antipatharians: Proxies Of Environmental Change, B. Williams, M.J. Risk, S.W. Ross, K.J. Sulak

United States Geological Survey: Staff Publications

Deep-water (307–697 m) antipatharian (black coral) specimens were collected from the southeastern continental slope of the United States and the north-central Gulf of Mexico. The sclerochronology of the specimens indicates that skeletal growth takes place by formation of concentric coeval layers. We used 210Pb to estimate radial growth rate of two specimens, and to establish that they were several centuries old. Bands were delaminated in KOH and analyzed for carbon and nitrogen stable isotopes. Carbon values ranged from _16.4‰ to _15.7‰; the oldest specimen displayed the largest range in values. Nitrogen values ranged from 7.7‰ to 8.6‰. …


Economics Of Manure Phosphorus Distribution From Beef Feeding Operations, William F. Kissinger, Raymond E. Massey, Richard K. Koelsch, Galen E. Erickson Jul 2006

Economics Of Manure Phosphorus Distribution From Beef Feeding Operations, William F. Kissinger, Raymond E. Massey, Richard K. Koelsch, Galen E. Erickson

Department of Biological Systems Engineering: Conference Presentations and White Papers

An economic model was developed to evaluate cost and value of manure distribution. Feedlots ranging in size from 2,500 head to 25,000 head one-time capacities were used as case studies to calculate excretion amounts from cattle fed diets with a range of phosphorus. Diet P and subsequent costs of distributing the manure were used to analyze the corresponding costs of manure distribution, in addition to determining the required available land needed to be in compliance with a nutrient management plan based on utilization of manure P by the crops grown.

The model illustrated when animals are fed diets of increasing …


Coupling Between Primary Terrestrial Succession And The Trophic Development Of Lakes At Glacier Bay, Alaska, D. R. Engstrom, Sherilyn C. Fritz Jan 2006

Coupling Between Primary Terrestrial Succession And The Trophic Development Of Lakes At Glacier Bay, Alaska, D. R. Engstrom, Sherilyn C. Fritz

Department of Earth and Atmospheric Sciences: Faculty Publications

The natural eutrophication of lakes is still an accepted concept in limnology, arising as it does from the earliest efforts to classify lakes and place them in an evolutionary sequence. Recent studies of newly formed lakes at Glacier Bay, Alaska, only partially support this idea, and suggest more variable trends in lake trophic development which are under local (catchment-level) control. Here we use sediment cores from several lakes in Glacier Bay National Park to examine the relationship between successional changes in catchment vegetation and trends in water-column nitrogen (a limiting nutrient) and lake primary production. Terrestrial succession at Glacier Bay …


Wet Corn Gluten Feed And Alfalfa Hay Levels In Dry-Rolled Corn Finishing Diets: Effects On Finishing Performance And Feedlot Nitrogen Mass Balance, T. B. Farran, Galen E. Erickson, Terry Klopfenstein, C. N. Macken, R. Lindquist Jan 2006

Wet Corn Gluten Feed And Alfalfa Hay Levels In Dry-Rolled Corn Finishing Diets: Effects On Finishing Performance And Feedlot Nitrogen Mass Balance, T. B. Farran, Galen E. Erickson, Terry Klopfenstein, C. N. Macken, R. Lindquist

Department of Animal Science: Faculty Publications

One-hundred ninety-two crossbred steers (initial BW= 351 ± 11 kg) were used to determine the effects of removing alfalfa hay (AH) from dry-rolled corn-based diets containing wet corn gluten feed (WCGF) on animal performance and nutrient (N and OM) mass balance in open feedlot pens. Steers were stratified by weight and assigned randomly to 24 pens (2 × 3 factorial) and fed for 132 d from June to October 2002. Experimental diets contained either 0 or 35% WCGF and 0, 3.75, or 7.5% AH, and were formulated to be isonitrogenous. For efficiency of gain, an interaction occurred (P = 0.09) …


Ec06-155 Nutrient Management For Agronomic Crops In Nebraska, Richard B. Ferguson Jan 2006

Ec06-155 Nutrient Management For Agronomic Crops In Nebraska, Richard B. Ferguson

University of Nebraska-Lincoln Extension: Historical Materials

Nebraska is blessed with fertile soil and vast supplies of groundwater which combine to create an environment well-suited to the production of corn, wheat, grain sorghum, alfalfa, edible beans, and other agronomic crops used for human or animal consumption.

This manual is a guide to nutrient use from all sources for the production of Nebraska's major agronomic crops: corn, winter wheat, grain sorghum, oats, alfalfa, dry edible beans, soybean, sugar beets, popcorn, sunflower, millet, potatoes, and cool and warm season grasses for hay and pasture. Part I of the manual contains information focusing on basic principles of soil fertility for …


G06-1621 Soybean Inoculation: Understanding The Soil And Plant Mechanisms Involved (Part One Of A Two-Part Series), Lori J. Abendroth, Roger Wesley Elmore, Richard B. Ferguson Jan 2006

G06-1621 Soybean Inoculation: Understanding The Soil And Plant Mechanisms Involved (Part One Of A Two-Part Series), Lori J. Abendroth, Roger Wesley Elmore, Richard B. Ferguson

University of Nebraska-Lincoln Extension: Historical Materials

Nitrogen gas (N2) comprises nearly 80 percent of total atmospheric gases, yet most organisms are unable to use N2 as a source of nitrogen. Legumes, such as soybean, are able to capture atmospheric nitrogen and utilize it through the process of nitrogen fixation. This NebGuide is part one of a two-part series on soybean inoculation. Here, we will investigate how soybean inoculation occurs and which environmental conditions impact nitrogen fixation.


2006 Beef Report Summaries, James Gosey Jan 2006

2006 Beef Report Summaries, James Gosey

University of Nebraska-Lincoln Extension: Historical Materials

Reports on recent beef research are briefly summarized in this publication. Summaries of the research featured in the 2006 Beef Report appear here. Topics include cow-calf, growing, finishing and beef products.


Fire Does Not Alter Vegetation In Infertile Prairie, Johannes M.H. Knops Jan 2006

Fire Does Not Alter Vegetation In Infertile Prairie, Johannes M.H. Knops

School of Biological Sciences: Faculty Publications

The paradigm in prairie ecology is that fire is one of the key factors deter-mining vegetation composition. fire can impact grassland ecosystems in various ways, including changing plant species composition and inducing nitro-gen loss. I found that 17 years of different burning frequencies in infertile grassland had only a minor impact on the vegetation composition and diversity. The only major impact from increasing the frequency of fires was a decrease of Poa pratensis abundance. However, other plant species did not r-spond to the change in Poa abundance. This result contrasts with previous studies in savannas and more productive grasslands, where …