Physical Sciences and Mathematics Commons^™

Long-Term Impacts Of Conservation Management Practices On Soil Carbon Storage, Stability, And Utilization Under Cotton Production In West Tennessee, Candace Brooke Wilson

Masters Theses

Biogeochemical cycling of soil carbon (C) is heavily influenced by conservation agricultural (CA) practices. This study examined SOC stability under three CA practices: reduced nitrogen (N) fertilizer application rate, cover cropping, and zero-tillage implemented for 31 years. Respiration rates measured from a 602-day incubation period were fitted to a double-pool first order exponential model of SOC decomposition. The active [respired] SOC pool showed distinct differences between applications of reduced (34N kg ha^-1 [-1]) and high fertilization rates (101N kg ha^-1) combined with tillage, and suggest that high fertilizer applications with conventional tillage allocated more C into a …

Working With Locals To Restore Biodiversity To A Rubber Dominated Landscape, Francis Commercon

Independent Study Project (ISP) Collection

Xishuangbanna, in Yunnan,China, contains the country’s highest concentration of biodiversity. Since the 1980s,rubber plantations have replaced a significant portion of the prefecture’s lowland Seasonal Tropical Rainforest, leading to wildlife habitat loss and other environmental issues.Monoculture farming practices also leave farmers economically vulnerable to market fluctuations. To learn the best solutions for increasing ecosystem services and income stability in rubber-dominated areas, the World Agroforestry Center (ICRAF) project Green Rubber engages smallholders directly in establishing and maintaining scientifically rigorous intercropping experiments in their villages.

Using Man’e village and the Green Rubber project as a case study, I asked to what degree and …

The Agricultural Footprints On The Environment, Philip Houtz

Kaleidoscope

Industrialized agricultural systems have given America a convenient and affordable means to supply a surplus of food products to its citizens. Transgenic technology, synthesized fertilizers, advanced pesticides, concentrated animal feeding operations (CAFOs), and the use of farm machinery have all contributed to humanity’s ability to feed the world’s rapidly growing population. However, the energy-intensive food operation of today may not be as ideal as we assume. Fossil fuels are burned to meet the energy requirements for the continual production of large quantities of fertilizer and to keep farm machines operational. Fertilizer and pesticide runoff from farmland ultimately drains into rivers …

Evaluating Animal Agriculture Impacts On Water Quality: Data Gaps In West Central Minnesota Case Study, Ed Brands

Environmental Studies Publications

Balancing the economic and food system contributions of animal agriculture with negative impacts such as water quality degradation has been a recurring question in Minnesota and other agricultural states (e.g., Iowa and North Carolina). Over the past 15 years significant federal- and state-level changes in the regulation of animal feeding operations (AFOs) and associated practices have attempted to improve water quality. The impacts of these changes are unclear; therefore, the main purpose of this project was to evaluate policies designed to protect water quality from manure runoff and spills within the context of a manageable geographic area. Project work was …

Effects Of Refuges On The Evolution Of Resistance To Transgenic Corn By The Western Corn Rootworm, Diabrotica Virgifera Virgifera Leconte, Jennifer Deitloff, Mike W. Dunbar, David A. Ingber, Bruce E. Hibbard, Aaron J. Gassmann

United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications

BACKGROUND: Diabrotica virgifera virgifera LeConte is a major pest of corn and causes over a billion dollars of economic loss annually through yield reductions and management costs. Corn producing toxins derived from Bacillus thuringiensis (Bt) has been developed to help manageD. v. virgifera.However, previous studies have demonstrated the ability of this species to evolve resistance to Bt toxins in both laboratory and field settings.

RESULTS: We used an experimental evolution approach to test the refuge strategies for delaying resistance of D. v. virgifera to corn producing Bt toxin Cry34/35Ab1. In the absence of refuges, D. v. virgifera developed resistance to …

Navigating A Pathway Toward Colorado's Water Future: A Review And Recommendations On Colorado's Draft Water Plan, Lawrence J. Macdonnell, Colorado Water Working Group

Books, Reports, and Studies

40 pages (includes color illustrations).