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1.
J Environ Manage ; 193: 483-490, 2017 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-28242115

RESUMEN

A water quality trading (WQT) program was promulgated in North Carolina to address water quality issues related to nutrients in the highly urbanizing Jordan Lake Watershed. Although WQT programs are appealing in theory, the concept has not proved feasible in several attempts between point and nonpoint polluters in the United States. Many application hurdles that create wedges between success and failure have been evaluated in the literature. Most programs, however, face multiple hurdles; eliminating one may not clear a pathway to success. Therefore, we identify and evaluate the combined impact of four different wedges including baseline, transaction cost, trading ratio, and trading cost in the Jordan Lake Watershed program. Unfortunately, when applied to the Jordan Lake program, the analysis clearly shows that a traditional WQT program will not be feasible or address nutrient management needs in a meaningful way. The hurdles individually would be difficult to overcome, but together they appear to be unsurmountable. This analysis shows that there is enough information to pre-identify potential hurdles that could inform policy makers where, and how, the concept might work. It would have saved time, energy, and financial resources if North Carolina had done so before embarking to implement their program in the Jordan Lake Watershed.


Asunto(s)
Lagos , Calidad del Agua , Humanos , Jordania , North Carolina , Estados Unidos , Contaminación del Agua
2.
J Environ Manage ; 168: 74-86, 2016 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-26696608

RESUMEN

The invasive tree Prosopis juliflora is known to cause negative impacts on invaded ranges. High P. juliflora eradication costs have swayed developing countries to follow a new and less expensive approach known as control through utilization. However, the net benefits of this new approach have not been thoroughly evaluated. Our objective was to assess the economic feasibility of selected P. juliflora eradication and utilization approaches that are currently practiced in one of the severely affected developing countries, Ethiopia. The selected approaches include converting P. juliflora infested lands into irrigated farms (conversion), charcoal production, and seed flour production. We estimate the costs and revenues of the selected P. juliflora eradication and utilization approaches by interviewing 19 enterprise owners. We assess the economic feasibility of the enterprises by performing enterprise, break-even, investment, sensitivity, and risk analyses. Our results show that conversion to irrigated cotton is economically profitable, with Net Present Value (NPV) of 5234 US$/ha over 10 years and an interest rate of 10% per year. Conversion greatly reduces the spread of P. juliflora on farmlands. Managing P. juliflora infested lands for charcoal production with a four-year harvest cycle is profitable, with NPV of 805 US$/ha. However, the production process needs vigilant regulation to protect native plants from exploitation and caution should be taken to prevent charcoal production sites from becoming potential seed sources. Though flour from P. juliflora pods can reduce invasions by destroying viable seeds, flour enterprises in Ethiopia are unprofitable. Conversion and charcoal production can be undertaken with small investment costs, while flour production requires high investment costs. Introducing new changes in the production and management steps of P. juliflora flour might be considered to make the enterprise profitable. Our study shows that control through utilization may be a viable P. juliflora management strategy under the right environmental setting.


Asunto(s)
Conservación de los Recursos Naturales/economía , Prosopis/crecimiento & desarrollo , Conservación de los Recursos Naturales/métodos , Ecosistema , Monitoreo del Ambiente , Etiopía , Humanos , Especies Introducidas , Semillas
3.
J Environ Qual ; 44(2): 382-90, 2015 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-26023957

RESUMEN

Nutrient enrichment of water resources has degraded coastal waters throughout the world, including in the United States (e.g., Chesapeake Bay, Gulf of Mexico, and Neuse Estuary). Agricultural nonpoint sources have significant impacts on water resources. As a result, nutrient management planning is the primary tool recommended to reduce nutrient losses from agricultural fields. Its effectiveness requires nutrient management plans be used by farmers. There is little literature describing nutrient management decision-making. Here, two case studies are described that address this gap: (i) a synthesis of the National Institute of Food and Agriculture, the Conservation Effects Assessment Project, and (ii) field surveys from three nutrient-impaired river basins/watersheds in North Carolina (Neuse, Tar-Pamlico, and Jordan Lake drainage areas). Results indicate farmers generally did not fully apply nutrient management plans or follow basic soil test recommendations even when they had them. Farmers were found to be hesitant to apply N at university-recommended rates because they did not trust the recommendations, viewed abundant N as insurance, or used recommendations made by fertilizer dealers. Exceptions were noted when watershed education, technical support, and funding resources focused on nutrient management that included easing management demands, actively and consistently working directly with a small group of farmers, and providing significant resource allocations to fund agency personnel and cost-share funds to farmers. Without better dialogue with farmers and meaningful investment in strategies that reward farmers for taking what they perceive as risks relative to nutrient reduction, little progress in true adoption of nutrient management will be made.

4.
J Environ Manage ; 149: 1-8, 2015 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-25463565

RESUMEN

This study proposes the use of marginal abatement cost curves to calculate environmental damages of agricultural systems in China's Loess Plateau. Total system costs and revenues, management characteristics and pollution attributes are imputed into a directional output distance function, which is then used to determine shadow prices and abatement cost curves for soil and nitrogen loss. Marginal abatement costs curves are an effective way to compare economic and conservation tradeoffs when field-specific data are scarce. The results show that sustainable agricultural practices can balance soil conservation and agricultural production; land need not be retired, as is current policy.


Asunto(s)
Agricultura/economía , Conservación de los Recursos Naturales/economía , Contaminación Ambiental/análisis , Modelos Económicos , Compuestos de Nitrógeno/análisis , Suelo/química , Agricultura/métodos , China , Conservación de los Recursos Naturales/métodos , Costos y Análisis de Costo , Contaminación Ambiental/economía , Humanos , Renta
5.
J Dairy Sci ; 96(10): 6366-77, 2013 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-23932128

RESUMEN

The use of sexed semen in the dairy industry has grown rapidly. However, high costs and low fertility have limited the use of this potentially valuable tool. This study used simulation to evaluate 160,000 combinations of key variables in 3 spheres of influence related to profit feasibility: (1) market (e.g., milk and calf prices), (2) dairy farm management (e.g., conception rates), and (3) technology (e.g., accuracy of sexing). These influential variables were used to determine the most favorable circumstances in which managers or technicians can effect change. Three distinct scenarios were created to model 3 initiatives that a producer might take with sexed semen: (1) using sexed semen on heifers, (2) using sexed semen on heifers and a fraction of the genetically superior cows, and (3) using sexed semen on heifers and a fraction of the genetically superior cows, and breeding all other cows with beef semen. Due to the large number of management, market, and technology combinations, a response surface and interpretive graphs were created to map the scope of influence for the key variables. Technology variables such as the added cost of sexed semen had relatively little effect on profitability, defined as net present value gain per cow, whereas management variables such as conception rate had a significant effect. Milk price had relatively little effect within each scenario, but was important across scenarios. Profitability was very sensitive to the price of dairy heifer calves, relative to beef and dairy bull calves. Scenarios 1 and 2 added about $50 to $75 per cow in net present value, which ranged from $0 to $200 and from $100 to $300, respectively. Scenario 3 usually was not profitable, primarily because fewer excess dairy replacement heifers were available for sale. Dairy heifer price proved to be the most influential variable, regardless of scenario.


Asunto(s)
Industria Lechera/economía , Inseminación Artificial/veterinaria , Semen , Preselección del Sexo/veterinaria , Animales , Cruzamiento/economía , Bovinos , Fertilidad , Fertilización , Inseminación Artificial/economía , Masculino , Carne , Leche/economía
6.
PeerJ ; 8: e9074, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32435536

RESUMEN

In the state of Colorado, a citizen ballot initiative to reintroduce gray wolves (Canis lupus) is eliciting polarization and conflict among multiple stakeholder and interest groups. Given this complex social landscape, we examined the social context surrounding wolf reintroduction in Colorado as of 2019. We used an online survey of 734 Coloradans representative in terms of age and gender, and we sampled from different regions across the state, to examine public beliefs and attitudes related to wolf reintroduction and various wolf management options. We also conducted a content analysis of media coverage on potential wolf reintroduction in 10 major daily Colorado newspapers from January 2019, when the signature-gathering effort for the wolf reintroduction initiative began, through the end of January 2020, when the initiative was officially added to the ballot. Our findings suggest a high degree of social tolerance or desire for wolf reintroduction in Colorado across geographies, stakeholder groups, and demographics. However, we also find that a portion of the public believes that wolves would negatively impact their livelihoods, primarily because of concerns over the safety of people and pets, loss of hunting opportunities, and potential wolf predation on livestock. These concerns-particularly those related to livestock losses-are strongly reflected in the media. We find that media coverage has focused only on a few of the many perceived positive and negative impacts of wolf reintroduction identified among the public. Our findings highlight the need to account for this diversity of perspectives in future decisions and to conduct public outreach regarding likely impacts of wolf reintroduction.

7.
Springerplus ; 5(1): 1692, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27752459

RESUMEN

The livestock sector serves as a foremost source of revenue for rural people, particularly in many developing countries. Among the livestock species, sheep and goats are the main source of livelihood for rural people in Ethiopia; they can quickly multiply, resilient and are easily convertible to cash to meet financial needs of the rural producers. The multiple contributions of sheep and goat and other livestock to rural farmers are however being challenged by climate change and variability. Farmers are responding to the impacts of climate change by adopting different mechanisms, where choices are largely dependent on many factors. This study, therefore, aims to analyze the determinants of choices of adaptation practices to climate change that causes scarcity of feed, heat stress, shortage of water and pasture on sheep and goat production. The study used 318 sample households drawn from potential livestock producing districts representing 3 agro-ecological settings. Data was analyzed using simple descriptive statistical tools, a multivariate probit model and Ordinary Least Squares (OLS). Most of the respondents (98.6 %) noted that climate is changing. Respondents' perception is that climate change is expressed through increased temperature (88 %) and decline in rainfall (73 %) over the last 10 years. The most commonly used adaptation strategy was marketing during forage shock (96.5 %), followed by home feeding (89.6 %). The estimation from the multivariate probit model showed that access to information, farming experience, number of households in one village, distance to main market, income of household, and agro-ecological settings influenced farmers' adaptation choices to climate change. Furthermore, OLS revealed that the adaptation strategies had positive influence on the household income.

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