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1.
Sci Total Environ ; 859(Pt 2): 160199, 2023 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-36402313

RESUMO

Aquaculture is currently the fastest growing food industry globally, and proposed expansion plans include substantial increases in production over the next decades. While this will improve global food security, contribute to the blue economy and create jobs locally, the potential negative impacts on the marine environment could be massive. The existing literature suggests that further research needs to be conducted into the dynamic nature of the social-ecological systems which host aquaculture. This paper presents the results of a choice experiment survey of Norwegian households' trade-offs between salmon production and job creation, and the detrimental impacts on the marine environment. Most respondents were at the outset neutral or supportive of plans for a substantial increase in aquaculture production. However, when informed about potential environmental impacts in terms of marine plastics and salmon lice affecting wild salmon stocks, and asked to trade these off against the positive effects, the majority opposed the plans and expressed a positive willingness-to-pay to avoid the planned expansion. Applying a hybrid mixed multinomial logit model we find that income, education and to some extent age, along with environmental attitudes, explain most of the variation in people's preferences. Support for large aquaculture expansion is higher among people who consume farmed salmon frequently and those living in areas with a high density of aquaculture farms. Hence, we do not find the so-called "not in my backyard" (NIMBY) effect. These results, which arguably contrast with previous studies of environmental impacts from aquaculture, can be useful for public planners globally as they consider expanding the blue economy.


Assuntos
Aquicultura , Salmão , Animais , Humanos , Aquicultura/estatística & dados numéricos , Aquicultura/tendências , Copépodes , Ecossistema , Noruega , Inquéritos e Questionários , Opinião Pública , Meio Ambiente , Conservação dos Recursos Naturais
2.
Conserv Biol ; 36(1): e13729, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-33786879

RESUMO

Many voluntary incentive programs for provision of forest ecosystem services (ES) have low participation rates, insufficient enrollment areas, and inefficient ecological outcomes. Understanding participation behavior in such programs has therefore become a crucial part of policy success. We synthesized a large body of literature on the behavior of nonindustrial private forest owners based on surveys of stated (intended) participation or data on actual participation in existing or hypothetical programs. Using metaregression analysis, we examined how methodological, program-characteristic, and economic-incentive variables affected participation rate estimates. Participation rates tended to be overestimated when landowner participation was elicited in hypothetical choice situations (compared with real situations) and when dichotomous choice surveys (compared with census data) were used. The marginal effect sizes were quite large, for example, a 31% increase with use of stated choices in hypothetical scenarios, and practitioners should therefore be aware of them. However, use of choice experiment surveys in a modified scenario based on existing programs had no effect on participation when all other determinants were controlled for. Participation rates decreased significantly as length of the contract increased and when there was no withdrawal option. These results suggest that perpetual contracts have a lower negative impact on participation than time-limited contracts with a duration of over 50 years. We confirmed that as compensation amounts increased, participation increased. One-time up-front payments were more effective in increasing initial participation than annual payments for contracts of over 5 years. We identified the robust determinants and the effect sizes of those determinants on landowner participation rate estimates, thereby contributing to a better understanding of forest owner behavior and offering useful insights to enable researchers and resource managers to improve the design and efficiency of new and existing forest ES programs.


Metaanálisis de la Participación de Terratenientes en los Programas de Incentivos Voluntarios para el Suministro de Servicios Ambientales Forestales Resumen Muchos programas de incentivos voluntarios para el suministro de servicios ambientales forestales tienen tasas bajas de participación, áreas insuficientes de inscripción y resultados ecológicos ineficientes. Por lo tanto, el entendimiento del comportamiento de participación en dichos programas se ha convertido en una parte crucial del éxito de las políticas. Sintetizamos un gran acervo de literatura sobre el comportamiento no industrial de los dueños de terrenos forestales privados con base en censos de la participación manifestada (pretendida) o información sobre la participación actual en los programas existentes o hipotéticos. Mediante un análisis de metarregresión, analizamos cómo las variables metodológicas, características del programa o económica-incentivas afectaron los estimaciones de las tasas de participación. Las tasas de participación tuvieron una tendencia a estar sobreestimadas cuando la participación se obtuvo por medio de situaciones hipotéticas de elección (en comparación con las situaciones reales) y cuando se usaron encuestas de elección dicotómica (en comparación con la información de los censos). Los tamaños del efecto marginal fueron bastante grandes, por ejemplo, un incremento del 31% con el uso de opciones manifestadas en los escenarios hipotéticos y, por lo tanto, los practicantes deberían estar conscientes de estos tamaños. Sin embargo, el uso de las encuestas con el experimento de elección en un escenario modificado con base en los programas existentes no tuvo efecto sobre la participación cuando todas las demás determinantes estuvieron controladas. Las tasas de participación disminuían significativamente conforme incrementaba la longitud del contrato y cuando no había opción de rescisión. Estos resultados sugieren que los contratos perpetuos tienen un impacto negativo más bajo sobre la participación que los contratos con límite de tiempo y una duración de más de 50 años. Confirmamos que conforme aumentan las cantidades de la compensación, incrementa la participación. Los pagos únicos y adelantados fueron más efectivos al momento de incrementar la participación inicial que los pagos anuales para los contratos de más de cinco años. Identificamos las determinantes contundentes y los tamaños de los efectos de aquellas determinantes sobre los estimados de las tasas de participación de los terratenientes, contribuyendo así a un mejor entendimiento del comportamiento de los dueños forestales y ofreciendo conocimiento útil para permitir a los investigadores y a los administradores de recursos mejorar el diseño y la eficiencia de los programas de servicios ambientales forestales nuevos y existentes.


Assuntos
Conservação dos Recursos Naturais , Ecossistema , Conservação dos Recursos Naturais/métodos , Florestas , Motivação , Inquéritos e Questionários
3.
Sci Total Environ ; 755(Pt 2): 142455, 2021 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-33049526

RESUMO

The feasibility of using biowaste for the production of biochar and its use in agriculture depends on its environmental and economic performance. This paper quantifies environmental and economic life cycle impacts of biochar production and agricultural use in six developing and middle-income countries (Ethiopia, Indonesia, Kenya, Peru, Vietnam, and China). Two types of production technologies typical for rural and urban areas were investigated (flame curtain kiln and gasifier, respectively), and comparisons were made with composting (either home composting or windrow composting) as alternative biowaste management systems. The results showed that both pyrolysis systems performed better than composting and both were expected to bring environmental benefits. The largest environmental benefits were observed for the gasifier systems, mainly due to the substitution of electricity production from the grid. Damage to ecosystems and human health ranged from -1 × 10-7 to -2 × 10-8 species×yr and from -1 × 10-5 to -5 × 10-6 DALY per kg of biowaste treated, respectively (negative scores indicating environmental benefits). However, net economic benefits were only achieved when low-cost simple kilns were used in countries with low labor cost, like Ethiopia, Kenya and Vietnam (net profit from 0.01 to 0.08 USD per kg of biowaste treated). Further, high investment and operating costs and relatively small electricity revenue from substituting the grid electricity resulted in gasifier scenarios being economically unsustainable (net loss from 0.29 to 1.58 USD per kg of biowaste treated). Thus, there are trade-offs between positive environmental impacts for society and net market loss for the individual decision-maker (company or individual farmer) that should be considered when making decisions regarding the implementation of biochar technology in developing and middle-income countries. The use of simple kilns in countries with relatively low labor costs appears to be favorable.


Assuntos
Países em Desenvolvimento , Ecossistema , Agricultura , Carvão Vegetal , China , Etiópia , Humanos , Indonésia , Quênia , Peru , Vietnã
4.
Environ Sci Technol ; 48(9): 4664-71, 2014 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-24678863

RESUMO

Biochar is the product of incomplete combustion (pyrolysis) of organic material. In rural areas, it can be used as a soil amendment to increase soil fertility. Fuel-constrained villagers may however prefer to use biochar briquettes as a higher-value fuel for cooking over applying it to soils. A systems-oriented analysis using life cycle assessment (LCA) and cost benefit analysis (CBA) was conducted to analyze these two alternative uses of biochar, applying the study to a rural village system in Indonesia. The results showed soil amendment for enhanced agricultural production to be the preferential choice with a positive benefit to the baseline scenario of -26 ecopoints (LCA) and -173 USD (CBA) annually pr. household. In this case, the positive effects of carbon sequestration to the soil and the economic value of the increased agricultural production outweighed the negative environmental impacts from biochar production and the related production costs. Use of biochar in briquettes for cooking fuel yielded negative net effects in both the LCA and CBA (85 ecopoints and 176 USD), even when positive health effects from reduced indoor air pollution were included. The main reasons for this are that emissions during biochar production are not compensated by carbon sequestration and that briquette making is labor-intensive. The results emphasize the importance of investigating and documenting the carbon storage effect and the agricultural benefit in biochar production-utilization systems for a sustainable use. Further research focus on efficient production is necessary due to the large environmental impact of biochar production. In addition, biochar should continue to be used in those soils where the agricultural effect is most beneficial.


Assuntos
Carvão Vegetal , Meio Ambiente , Fertilizantes , População Rural , Fatores Socioeconômicos , Solo , Agricultura/métodos , Carbono , Indonésia
5.
Risk Anal ; 31(9): 1381-407, 2011 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-21957946

RESUMO

We conduct, to our knowledge, the first global meta-analysis (MA) of stated preference (SP) surveys of mortality risk valuation. The surveys ask adults their willingness to pay (WTP) for small reductions in mortality risks, deriving estimates of the sample mean value of statistical life (VSL) for environmental, health, and transport policies. We explain the variation in VSL estimates by differences in the characteristics of the SP methodologies applied, the population affected, and the characteristics of the mortality risks valued, including the magnitude of the risk change. The mean (median) VSL in our full data set of VSL sample means was found to be around $7.4 million (2.4 million) (2005 U.S. dollars). The most important variables explaining the variation in VSL are gross domestic product (GDP) per capita and the magnitude of the risk change valued. According to theory, however, VSL should be independent of the risk change. We discuss and test a range of quality screening criteria in order to investigate the effect of limiting the MA to high-quality studies. When limiting the MA to studies that find statistically significant differences in WTP using external or internal scope tests (without requiring strict proportionality), we find that mean VSL from studies that pass both tests tend to be less sensitive to the magnitude of the risk change. Mean VSL also tends to decrease when stricter screening criteria are applied. For many of our screened models, we find a VSL income elasticity of 0.7-0.9, which is reduced to 0.3-0.4 for some subsets of the data that satisfy scope tests or use the same high-quality survey.


Assuntos
Política Ambiental , Política de Saúde , Comportamento de Redução do Risco , Meios de Transporte
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