2,817 research outputs found
Nitrogen as a Capital Input and Stock Pollutant: A Dynamic Analysis of Corn Production and Nitrogen Leaching under Non-Uniform Irrigation
A spatially dynamic programming model of nonuniform irrigation is developed to investigate the nitrogen leaching problem associated with irrigated agriculture. We evaluate the importance of temporal and spatial elements in (i) appropriately modeling the interseasonal corn production problem with nitrogen carry-over and leaching under non-uniform irrigation, and (ii) in adequately evaluating alternative policy instruments for pollution control. Comparisons of the time profiles under spatially variable nitrogen levels arising from nonuniform irrigation are provided along with an evaluation of three different price-based policy instruments for reducing nitrogen leaching.Environmental Economics and Policy,
HAVE INCENTIVE BASED POLICIES BEEN OVERSOLD?
Comparisons of alternative pollution control instruments over the past thirty years show quite disparate results for seemingly comparable situations. This research demonstrates how the magnitude of the estimated cost savings associated with incentive-based instruments is influenced by two important factors: (i) separability assumptions between emissions and output, and (ii) participation criteria.Environmental Economics and Policy,
THE VALUE OF INCREASING THE LENGTH OF DEER SEASON IN OHIO
Growing deer populations are controlled through changes in hunting regulations including changes in both hunter bag limits and season length. Such action results in direct benefits to hunters and indirect benefits to motorists and the agricultural sector as a lower deer population leads to fewer incidences of human-deer encounters. Traditional recreation demand models are often employed to examine the welfare implications of changes in daily hunting bag limits. Studies measuring the effects of changes in season length, however, are noticeably absent from the literature. This study uses a nested random utility model to examine hunter choice over site and season selection to derive the welfare implications of changes in season length.random utility models, recreation, Resource /Energy Economics and Policy,
AJAE Appendix: Spatial Dynamics of Water and Nitrogen Management in Irrigated Agriculture
The material contained herein is supplementary to the Article named in the title and published in the American Journal of Agricultural Economics, forthcoming.Crop Production/Industries, Farm Management,
Effects of Nutrient Restrictions on Confined Animal Facilities: Insights from a Structural Model
Nutrient emissions from animal feeding operations continue to degrade water and air quality. New regulations will limit the amounts of nutrients that can be locally applied to land. In this article, a structural-dynamic model of a livestock-crop operation is calibrated with data from a representative farm and is used to predict the effects of nitrogen regulations. Policy simulations clarify the importance of dynamic elements and demonstrate three main results: (1) cost estimates are relatively high; (2) cross-media pollution effects are potentially large; and (3) improved input management appears most promising for reducing both emissions and waste management costs. Implications for policy and future research are discussed.Ammonia, animal feeding operation, cross-media pollution, dairy, dynamic optimization, groundwater, nitrate, nitrogen, nutrient management plan, Livestock Production/Industries,
A DYNAMIC EXERCISE IN REDUCING DEER-VEHICLE COLLISIONS: MANAGEMENT THROUGH VEHICLE MITIGATION TECHNIQUES AND HUNTING
The costs of deer-vehicle collisions (DVCs) nationwide are estimated to be in excess of $1 billion annually. In this study, factors contributing to the abundance of DVCs are identified and the potential effectiveness of various deer management strategies in reducing DVCs is investigated. The added benefits of such strategies are also evaluated in a bioeconomic context by comparing alternative outcomes achievable from implementing DVC mitigation techniques. Focusing on Ohio, results suggest potentially large economic gains exist from reducing DVCs, especially with strategies that combine both deer management schemes and DVC mitigation techniques.Resource /Energy Economics and Policy,
INTEGRATED DRAINWATER MANAGEMENT IN IRRIGATED AGRICULTURE
Drainwater management strategies include source control, reuse, treatment, and evaporation ponds; questions of interest are efficient management, policy instruments, and sustainability. A high level of source control is indicated absent reuse due to the relatively high cost of evaporation ponds; this is accomplished largely through high uniformity/high cost irrigation systems. With reuse, the primary form of source control is reduction in land area devoted to freshwater production; the released land goes to reuse production. Reuse appears as an economically promising solution to the drainage problem. A high level of net returns is achieved while maintaining overall hydrologic balance in the system. Economic efficiency and hydrologic balance may be attained through pricing or market schemes. With pricing, growers are charged for deep percolations flows, while reuse and evaporation pond operators are paid for extractions. With markets, permit supply is generated by extractions from the water table, while permit demand is generated by deep percolation. Competitive equilibrium exists, is efficient, and implies hydrologic balance. The analysis suggests that a high level of agricultural production may be possible for some period of time while still maintaining environmental quality.Resource /Energy Economics and Policy,
MICROECONOMICS OF IRRIGATION WITH SALINE WATER
Water management and reuse at the field level are analyzed under saline, limited drainage conditions. A function relating crop yield and deep percolation flows to applied water and salinity concentration is developed. This function fits simulated data well and is tractable for theoretical and empirical analysis of irrigation economics. With a single irrigation source, irrigation water for cotton and tomatoes at first increases and the decreases with salt concentration. Drain-water reuse is found to be an efficient strategy in events of high surface-water prices and costly solutions to drainage-related environmental problems. However, blending freshwater and drainage appears plausible only under surface water scarcityResource /Energy Economics and Policy,
Competition between Kondo screening and indirect magnetic exchange in a quantum box
Nanoscale systems of metal atoms antiferromagnetically exchange coupled to
several magnetic impurities are shown to exhibit an unconventional re-entrant
competition between Kondo screening and indirect magnetic exchange interaction.
Depending on the atomic positions of the magnetic moments, the total
ground-state spin deviates from predictions of standard
Ruderman-Kittel-Kasuya-Yosida perturbation theory. The effect shows up on an
energy scale larger than the level width induced by the coupling to the
environment and is experimentally verifiable by studying magnetic field
dependencies.Comment: 5 pages, 2 figures, v3 with minor change
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