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Registros recuperados: 15
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Benefits of Protecting Rural Water Quality: An Empirical Analysis AgEcon
Crutchfield, Stephen R.; Feather, Peter; Hellerstein, Daniel.
Concerns about the impact of farm production on the quality of the Nation's drinking and recreational water resources have risen over the past 10 years. Because point sources of pollution were controlled first, agricultural nonpoint sources have become the Nation's largest remaining single water-quality problem. Both public and private costs of policies that address the conflict between agricultural production and water quality are relevant, but measuring the off-farm benefits and costs of changing water quality is difficult. Many of the values placed on these resources are not measured in traditional ways through market prices. This report explores the use of nonmarket valuation methods to estimate the benefits of protecting or improving rural water...
Tipo: Report Palavras-chave: Water quality; Nonpoint source pollution; Environmental quality; Agricultural production; Costs; Benefits; Resource /Energy Economics and Policy.
Ano: 1995 URL: http://purl.umn.edu/33949
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Dynamic regulation of nonpoint source pollution when the number of emitters is large AgEcon
Tsur, Yacov; de Gorter, Harry.
When a nonpoint source pollution process involves many polluters, each taking his own contribution to aggregate pollution to be negligible, ambient-based policies become ineffective due to lack of strategic interactions between dischargers. We offer a regulation mechanism for this case. The mechanism consists of inter-period and intra-period components. The first exploits ambient (aggregate) information to derive the optimal pollution and aggregate emission processes and the ensuing social price of emission. The intra-period mechanism takes as given the social price of emission and implements the optimal output-abatement-emission allocation across the heterogenous, privately informed firms in each time period. The mechanism gives rise to the full...
Tipo: Article Palavras-chave: Nonpoint source pollution; Abatement; Stock externality; Dynamic regulation; Markov decision process; Asymmetric information; Crop Production/Industries; C61; D82; H23; L51; Q58.
Ano: 2012 URL: http://purl.umn.edu/122124
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Incentive-Based Land Use Policies and Water Quality in the Chesapeake Bay AgEcon
Walls, Margaret; McConnell, Virginia D..
The activities conducted on land surrounding the Chesapeake Bay directly affect pollution levels in the Bay, and they do so in complex and varied ways. Policy attention has been focused, for the most part, on modifying these activities within a particular land use category but not on wholesale changes in land use. For example, farmers are encouraged to use "best management practices" (BMPs) that focus on fertilizer use, crop covers, and the like; residential and commercial developers are encouraged to manage stormwater runoff; and wastewater treatment plants are required to meet technology-based standards. But the amount of land in urbanized uses relative to the amount in farming, forestry, and open space has not been given the attention it deserves. In...
Tipo: Working or Discussion Paper Palavras-chave: Development impact fees; Nonpoint source pollution; Purchase of development rights; Transferable development rights; Land Economics/Use; Q53; Q58; R14.
Ano: 2004 URL: http://purl.umn.edu/10843
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Linking Resilience Theory and Diffusion of Innovations Theory to Understand the Potential for Perennials in the U.S. Corn Belt Ecology and Society
Atwell, Ryan C; Iowa State University; ryancardiffatwell@gmail.com; Schulte, Lisa A; Iowa State University; lschulte@iastate.edu; Westphal, Lynne M; U.S. Forest Service Northern Research Station; lwestphal@fs.fed.us.
In the last 200 yr, more than 80% of the land in the U.S. Corn Belt agro-ecosystem has been converted from natural perennial vegetation to intensive agricultural production of row crops. Despite research showing how re-integration of perennial vegetation, e.g., cover crops, pasture, riparian buffers, and restored wetlands, at strategic landscape positions can bolster declining regional ecosystem functions, the amount of land area devoted to row crop production in the Corn Belt continues to increase. As this region enters a time of fast-paced and uncertain reorganization driven by the emerging bioeconomy, changes in land use will continue to take place that will impact the resilience of the Corn Belt’s linked social and ecological systems for...
Tipo: Peer-Reviewed Reports Palavras-chave: Adaptive co-management; Agriculture; Iowa; Learning; Nonpoint source pollution; Restoration; Scale; Social-ecological systems; Row crops; Corn Belt.
Ano: 2009
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Nonpoint Source Pollution Taxes and Excessive Tax Burden AgEcon
Karp, Larry S..
If a regulator is unable to measure firms' individual emissions, an ambient tax can be used to achieve the socially desired level of pollution. With this tax, each firm pays a unit tax on aggregate emissions. In order for the tax to be effective, firms must recognize that their decisions affect aggregate emissions. When firms behave strategically with respect to the tax-setting regulator, under plausible circumstances their tax burden is lower under an ambient tax, relative to the tax which charges firms on the basis of individual emissions. Firms may prefer the case where the regulator is unable to observe individual firm emissions, even if this asymmetric information causes the regulator to tax each firm on the basis of aggregate emissions.
Tipo: Working or Discussion Paper Palavras-chave: Ambient tax; Nonpoint source pollution; Moral hazard; Asymmetric information; Differential games; Environmental Economics and Policy; D82; H20; H40; Q20.
Ano: 1998 URL: http://purl.umn.edu/25100
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On the regulation of unobserved emissions AgEcon
Tsur, Yacov; de Gorter, Harry.
Regulation of nonpoint source pollution often relies in one way or another on policy instruments based on ambient indicators. For well-known reasons, enforcement of ambient-based policies is, at best, limited. If no individual choices or actions are observed, than ambient-based regulation might be the only feasible approach. Often, some relevant individual indicators, such as output or certain inputs, are observable. For such cases, we offer a regulation mechanism that does away with ambient indicators. The mechanism implements the optimal output-abatement-emission allocation and gives rise to the full information outcome when the social cost of transfers is nil. Special attention is given to the regulation of (unobserved) abatement.
Tipo: Working or Discussion Paper Palavras-chave: Nonpoint source pollution; Abatement; Asymmetric information; Regulation mechanism; Implementation.; Environmental Economics and Policy.
Ano: 2011 URL: http://purl.umn.edu/116228
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Phosphorus Forms in Sediments as Indicators of Anthropic Pressures in an Agricultural Catchment in Southern Brazil Rev. Bras. Ciênc. Solo
Tiecher,Tales; Schenato,Ricardo Bergamo; Santanna,Maria Alice; Caner,Laurent; Santos,Danilo Rheinheimer dos.
ABSTRACT Phosphorus (P) fractionation is a suitable procedure to ascertain P lability in sediments and is able to distinguish sources of P under different soil management practices in a catchment. Brazil is the second largest producer and the largest exporter of tobacco in the world. Inadequate management of cultivated areas exposes the soil to erosion processes, accelerating the transfer of sediment and P to water bodies, which leads to eutrophication. We evaluated the P forms in suspended sediments collected at two rainfall events in the stream of a small catchment in the state of Rio Grande do Sul. The samples were collected upstream and downstream areas in three sub-catchments with different degrees of anthropogenic pressure and in three phases of the...
Tipo: Info:eu-repo/semantics/article Palavras-chave: Phosphorus fractionation; Watershed; Nonpoint source pollution; Eutrophication; Land use.
Ano: 2017 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-06832017000100431
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Reducing Crop Nutrient Applications: The Yield Reserve Program AgEcon
Metcalfe, Todd; Bosch, Darrell J.; Pease, James W..
A proposed Yield Reserve Program designed to compensate farmers for any reduced yields resulting from reduced nitrogen (N) application rates below recommended rates is evaluated. Assuming that farmers currently follow extension recommendations for applying N, Yield Reserve Program participation reduces expected net revenue by $10 to $13/ha. The Yield Reserve Program reduces expected net revenue by $17 to $20/ha for farmers who apply N to maximize expected net revenue. Farmers’ costs of participation increase with lower probabilities of inadequate rainfall and higher corn prices and decline with higher N prices. The Yield Reserve Program can significantly reduce N applications to cropland, which may reduce N content of surface waters, but the costs to...
Tipo: Conference Paper or Presentation Palavras-chave: Compliance cost; Nitrogen fertilizer; Nonpoint source pollution; Policy; Yield response function; Crop Production/Industries.
Ano: 2007 URL: http://purl.umn.edu/9762
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RISK AND SITE FACTORS AFFECTING POTENTIAL NITROGEN DELIVERY IN THE VIRGINIA COASTAL PLAIN AgEcon
Peng, Wei; Bosch, Darrell J..
The effects of cropland slope, distance to surface water, farmers' risk attitudes, and farmers' nitrogen (N) fertilizer applications on potential N delivery to streams and costs of reducing N delivery were evaluated for a representative Virginia peanut-cotton farm. Target MOTAD and generalized stochastic dominance were used to select preferred plans for different levels of risk aversion. Costs of reducing N delivery were lower on farms where fields were located close to surface water, where N was overapplied relative to extension fertilizer recommendations, and where the operator was risk averse. Cropland slope had less effect on cost of reducing N delivery relative to other factors.
Tipo: Journal Article Palavras-chave: Cost; Nonpoint source pollution; Risk programming; Simulation; Stochastic dominance; Targeting; Environmental Economics and Policy.
Ano: 2001 URL: http://purl.umn.edu/15287
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Soil tillage systems and herbicide leaching in Brazil. Repositório Alice
CERDEIRA, A. L.; SOUZA, M. D. de; BOLONHEZI, D.; QUEIROZ, S. C. do N. de; FERRACINI, V. L.; LIGO, M. A. V.; PESSOA, M. C. P. Y.; SMITH JR, S..
The Guarany aquifer located in South America has a dimension of approximately 1,200,000 Km2 and spreads to areas of eight Brazilian states plus parts of Argentina, Uruguay and Paraguay. The region of Ribeirao Preto City, located in Southeast of Brazil, Sao Paulo State, is a sugarcane, soybean, peanuts, and corn producing area. This region is also an important recharge area to the aquifer. Intensive farming on the area has demanded constant use of herbicides and fertilizers. Triazine herbicides such as atrazine, ametryn, and simazine are used on the area and are known to have potential for groundwater contamination. Currently most of the sugar cane crop is mechanically harvested without burning. This practice allows the straw to decompose in soil, maintain...
Tipo: Artigo em anais de congresso (ALICE) Palavras-chave: Águas subterrâneas; Hidrologia; Groundwater; Hydrology; Soil transport processes; Nonpoint source pollution.
Ano: 2005 URL: http://www.alice.cnptia.embrapa.br/handle/doc/1020673
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The Role of Information and Prices in the Nitrogen Fertilizer Management Decision: New Evidence from the Agricultural Resource Management Survey AgEcon
Williamson, James M..
This article investigates the impact of agronomic and price information on nitrogen fertilizer management. Excessive nitrogen applications can cause environmental degradation, and it is important to understand how information influences the application decision in order to develop effective conservation policies. The impact of soil N-tests on the rate of applied nitrogen is estimated. Farmers who use a soil test reduce their use of commercial nitrogen by up to 83 lbs/acre relative to non-testers. New evidence indicates that rising fertilizer prices encourage farmers to manage nitrogen more carefully. Estimated price elasticities of quantity demanded range from -1.67 to -1.87.
Tipo: Article Palavras-chave: Nitrogen demand elasticities; Nitrogen fertilizer management; Nonpoint source pollution; Soil N-testing; Agribusiness; Institutional and Behavioral Economics.
Ano: 2011 URL: http://purl.umn.edu/119180
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Tradable Permits Under Threat to Manage Nonpoint Source Pollution AgEcon
Ali, Murad; Le Grusse, P.; Rio, Patrick.
In this article we treat the problem of nonpoint source pollution as a problem of moral hazard in group. To solve this kind of problem we consider a group performance based tax coupled to tradable permits market. The tax is activated if the group fails to meet the ambient standard. So the role of the tax is to provide an incitation to ensure that the agents provide the abatement level necessary to achieve the standard. The role of the tradable permits market is to distribute effectively this abatement level through the price of the permits which rises with the exchange of the permits.
Tipo: Conference Paper or Presentation Palavras-chave: Nonpoint source pollution; Ambient tax; Tradable permits market; Environmental Economics and Policy.
Ano: 2008 URL: http://purl.umn.edu/44414
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Using Carbon Offsets to Fund Agricultural Conservation Practices in a Working-Lands Setting AgEcon
Reeling, Carson J.; Gramig, Benjamin M..
The nitrogen cascade concept indicates that agriculture serves as a significant link between emissions of the potent greenhouse gas (GHG) nitrous oxide and losses of nitrate-N to surface waters. Conservation practices have the potential to exploit this link, as their implementation is found to reduce fluxes of GHGs and nonpoint source (NPS) water pollution. Several studies have recognized this link and have documented the potential to improve environmental quality through the use of programs which retire land, the cost of which can be offset by the sale of carbon credits. However, the ability to use land for both agricultural production and environmental conservation is important. As such, this study provides a novel analytical framework that is used...
Tipo: Conference Paper or Presentation Palavras-chave: Greenhouse gases; Nonpoint source pollution; Agricultural conservation practices; DAYCENT; SWAT; Genetic algorithm; Environmental Economics and Policy.
Ano: 2011 URL: http://purl.umn.edu/103577
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Using Numerical Dynamic Programming to Compare Passive and Active Learning in the Adaptive Management of Nutrients in Shallow Lakes AgEcon
Bond, Craig A.; Loomis, John B..
This paper illustrates the use of dual/adaptive control methods to compare passive and active adaptive management decisions in the context of an ecosystem with a threshold effect. Using discrete-time dynamic programming techniques, we model optimal phosphorus loadings under both uncertainty about natural loadings and uncertainty regarding the critical level of phosphorus concentrations beyond which nutrient recycling begins. Active management is modeled by including the anticipated value of information (or learning) in the structure of the problem, and thus the agent can perturb the system (experiment), update beliefs, and learn about the uncertain parameter. Using this formulation, we define and value optimal experimentation both ex ante and ex post. Our...
Tipo: Working or Discussion Paper Palavras-chave: Adaptive control; Adaptive management; Dynamic programming; Value of experimentation; Value of information; Nonpoint source pollution; Learning; Decisions under uncertainty; Resource /Energy Economics and Policy.
Ano: 2008 URL: http://purl.umn.edu/108720
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Yield Reserve Program Costs in the Virginia Coastal Plain AgEcon
Metcalfe, Todd; Bosch, Darrell J.; Pease, James W.; Alley, Mark M.; Phillips, Steve B..
A proposed Yield Reserve Program designed to compensate farmers for any reduced yields resulting from nitrogen (N) application rates reduced to below recommended rates is evaluated. Assuming that farmers currently follow Extension recommendations for applying N, Yield Reserve Program participation reduces expected net revenue by $10 to $13/ha. The Yield Reserve Program reduces expected net revenue by $17 to $20/ha for farmers who apply N to maximize expected net revenue. Farmers’ costs of participation increase with lower probabilities of inadequate rainfall and higher corn prices and decline with higher N prices. The Yield Reserve Program can significantly reduce N applications to cropland, which may reduce N content of surface waters, but the costs to...
Tipo: Journal Article Palavras-chave: Compliance cost; Nitrogen fertilizer; Nonpoint source pollution; Policy; Yield response function; Agricultural and Food Policy; Crop Production/Industries.
Ano: 2007 URL: http://purl.umn.edu/44697
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