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1.
    
Natural enemies (NEs) provide an important ecosystem service by preying on variety of pests in agricultural crop production systems. Current management practices of both primary and secondary pests in agricultural production principally rely on the use of pesticides with associated negative social and environmental consequences/externalities. Excessive use of pesticides against primary pets can remove NEs from the agro‐ecosystem and amplify susceptibility of the system to outbreaks of secondary pests. The combined effect of NEs on primary and secondary pests has received limited attention. This study uses an intraseasonal bioeconomic model to explicitly take into account biological interactions among primary pests, secondary pests, and NEs assuming decision makers’ profit maximizing behavior. The model explicitly captures the opportunity cost of injury to NE in terms of both primary and secondary pest suppression by NE. The results show that in the context of the green peach aphid (primary pest) and two‐spotted spider mite (secondary pest) in potato production, inclusion of NE into pest mitigation strategy can increase returns by 2%.  相似文献   

2.
This note reports on the results of a choice experiment survey of 400 people in England and Wales, conducted to estimate the value that society places on changes to the size of the badger population. The study was undertaken in the context of the possible need to reduce the badger population by culling to help control bovine tuberculosis in cattle. The study found that people were concerned about the problem of bovine tuberculosis in cattle, which was reflected in their willingness to pay to control the disease, and gave a relatively low value to changes in the size of the badger population (within limits). However, people did not like the idea of a policy that intentionally killed large numbers of badgers and had a relatively very high willingness to pay not to have such a policy.  相似文献   

3.
    
There is a broad literature on the impact of Bt cotton adoption in different countries, but few studies have explicitly looked at environmental and health effects from an economic perspective. We analyse the impact of Bt cotton on environmental efficiency in Pakistan, using farm survey data and a doubly heteroskedastic stochastic production function framework. Negative environmental and health effects of chemical pesticide use are quantified with the environmental impact quotient. Bt‐adopting farms have higher cotton yields, while using lower pesticide quantities and causing less environmental damage. Bt farms are both technically and environmentally more efficient than non‐Bt farms. Bt adoption increases environmental efficiency by 37%. Achieving the same reduction in negative environmental and health impact without Bt would cost conventional cotton farmers US$ 54 per acre in terms of foregone yields and revenues (7% of total revenues). Extrapolating this shadow price of the technology's health and environmental benefits to the total Bt cotton area in Pakistan results in an aggregate value of US$ 370 million. These benefits are in addition to the profit gains for Bt‐adopting farmers. Our results suggest that Bt technology can contribute to sustainable agricultural development.  相似文献   

4.
    
This research aimed at identifying and estimating the relative weight assigned to the preferred traits of indigenous cow population in the most dominant crop–livestock mixed production system in Central Ethiopia. A choice experiment approach was employed to elicit the preferences and a random parameters logit model was used to estimate the relative importance of the preferred attributes of indigenous cows. The results show that fertility, disease resistance and calf vigour traits are at least as important as milk. The location the cows are brought from is also an important attribute for buyers. Results from the simulation on the influence of changes in attribute levels showed that fertility and disease resistance affect preferences more than other traits. The findings suggest that the smallholder community in this part of Ethiopia depends on semi‐subsistence agriculture and so livestock development interventions should focus on a multitude of reproductive and adaptive traits that stabilise the herd structure rather than focusing on traits that are only important for commercial purposes.  相似文献   

5.
    
This article analyses the effect of inducing institutional and value learning in a choice experiment survey concerning food safety. Respondents were subjected to two types of treatments, namely, Advance Disclosure (ADV) and Instructional Choice Set (ICS). Employing a split‐sample setup, we test the effect of providing ICS and ADV in two treatment groups relative to a control group where learning is not induced. We further test and compare the effects of ADV and ICS directly against each other. We find some evidence that ICS reduces institutional uncertainty as intended. Moreover, the results suggest that both ICS and ADV could potentially remove a gender‐specific status‐quo bias.  相似文献   

6.
    
This study addresses the trade‐off between nutrition and taste in expenditure on breakfast cereal, milk, bread, and soft drinks. Within each category, products have similar cost and convenience, but have markedly different flavor and nutritional content. Using annual expenditure data for a large sample of households participating in the ACNielsen Homescan system, we regress a measure of “healthiness” on household demographics and market prices, and find that households with college‐educated heads and higher incomes made significantly healthier choices in all four categories. These effects are puzzling in that the nutritional differences between products were well known to consumers, and there are no cost or convenience differences between them. The presence of children was associated with less healthy choices, especially for cereal and bread, while older households made healthier choices in all categories except milk.  相似文献   

7.
The purpose of this article is to analyze the relation between public health and the regulations of Maximum Residue Limit (MRL) of pesticides. Many authors underline the role of trade protectionism in fixing these limits, whereas these regulations should be intended for public health protection. We first establish the link between the MRL for a given chemical in plant products and its level of toxicity. In order to perform this analysis, we cross the FAS USDA MRL database and the classification of the long‐term toxicological effects (LTE) for active substances provided by SAgE pesticide. We then compute a synthetic and polyvalent tool, namely, “Health Score,” which provides a first overview of the link between LTE and MRL by country. Then this score is regressed in a logit model in order to identify the relationship between the countries’ Health Score and the socioeconomic and political characteristics of such areas. Results highlight the importance of public health expenditures in determining the settings of MRL toward stricter levels.  相似文献   

8.
This article employs a propensity score‐matching approach to examine the direct effects of adoption of Bacillus thuringiensis (Bt) cotton on yields, pesticide demand, household income and poverty, using cross‐sectional data from a survey of farmers in the Punjab province of Pakistan. Generally, the findings reveal that adoption of the new technology exerts a positive and significant impact on cotton yields, household income and poverty reduction, and a negative effect on the use of pesticides. The positive and significant impact of the technology on yields and household income is consistent with the potential role of new agricultural technology in directly reducing rural poverty through increased farm household income.  相似文献   

9.
    
Soil erosion, in its various forms, is caused or aggravated by agricultural activities. Mitigation of surface erosion comprises the construction of shelterbelts, fencing, riparian buffering, and stock reduction. Mitigation of mass‐movement erosion, in turn, takes the form of spaced planting of trees to maintain a persistent, healthy, and complete ground cover. In this article, we assess the economic implications to agriculture of the adoption of mitigation alternatives for erosion control in the Waikato District, New Zealand. The Waikato District presents a spatial pattern of erosion that affects profitability of dairy, and sheep and beef enterprises. We use the Universal Soil Loss Equation and the New Zealand Empirical Erosion Model to estimate erosion figures that are then fed into an economic‐focused, nonlinear, partial equilibrium mathematical programming model of New Zealand land use. Different scenarios are constructed for surface and mass‐movement soil erosion targets ranging from 0% to 50% below baseline levels. We find that achieving surface erosion targets is more expensive than mass‐movement targets, and results in different responses in regional‐level costs, land use, enterprise net revenue, and adoption of mitigation alternatives.  相似文献   

10.
    
Understanding farmers’ willingness to participate in agricultural payment‐for‐environmental‐services (PES) programmes is an essential precondition for designing effective and efficient programmes. Willingness to participate is typically examined via stated preference surveys using the standard hurdle model for whether and how much to participate. Among respondents who decline to participate, such analyses cannot distinguish between respondents who declined due to the payment level and those who were not interested at all. This paper applies a double hurdle model to incorporate a prior condition for whether a respondent is even willing to consider participating in the PES market. The model uses a unique stated preference survey permitting separation of the consideration and enrolment decisions of 1,700 farmers in Michigan, USA. The first hurdle probit model suggests that farmers’ willingness to consider PES chiefly depends on farm and farmer characteristics, while the second hurdle tobit model shows that decisions on whether and how much to enrol depend more on the payment offer and marginal benefit–cost criteria. This study provides fresh insights on facilitating farmer participation in PES programmes using tiered strategies that differ in costs of programme payment and administration.  相似文献   

11.
    
Using linear programming in bio‐economic farm modelling often results in overspecialised model solutions. The positive mathematical programming (PMP) approach guarantees exact calibration to base year data but the forecasting capacity of the model is affected by necessary but arbitrary assumptions imposed during calibration. In this article, a new PMP variant is presented which is based on less arbitrary assumptions that, from a theoretical point of view, are closer to the actual decision making of the farmer. The PMP variant is evaluated according to the predictions of the bio‐economic farm model, developed within the framework for integrated assessment of agricultural systems in Europe (SEAMLESS). The forecasting capacity of the model calibrated with the standard PMP approach and the alternative PMP variant, respectively, is tested in ex‐post experiments for the arable farm types of Flevoland (the Netherlands) and Midi‐Pyrenees (France). The results of the ex‐post experiments, in which we try to simulate farm responses in 2003 using a model calibrated to 1999 data, show that the alternative PMP variant improves the forecasting capacity of the model in all tested cases.  相似文献   

12.
    
China faces health and environmental problems associated with the use of agricultural chemicals, including pesticides. While previous studies have found that risk aversion affects pesticide use in China, they have focused primarily on commercial cotton farmers. In this study, we consider the case of smaller, semisubsistence and subsistence farmers in a poor and landlocked province of China (Yunnan). We use a field experiment to measure risk aversion and collect detailed data on farm production and input use to specifically ask whether risk aversion affects pesticide use, and whether this effect differs for subsistence farmers producing exclusively for home consumption versus semisubsistence farmers who produce both for home and the market. We find that risk aversion significantly increases pesticide use, particularly for subsistence farmers and for market plots by semisubsistence farmers. Further, this effect of risk aversion significantly decreases with farm size for subsistence farmers, but not for semisubsistence farmers, implying that pesticide use may be used to ensure sufficient food supply for home consumption. Finally, we find barriers to the use of pesticides for subsistence farmers, both in terms of financial constraints and economies of scale. This finding implies that risk‐mitigation strategies, such as crop insurance, may not target food security concerns of subsistence farmers. Given these different motivations for pesticide use, policymakers may wish to consider effective tools to support rural food security for farmers in the poorer regions of China in order to decrease pesticide use.  相似文献   

13.
    
This research investigates how the public of a middle‐income country, Thailand, values ecosystem services associated with irrigated rice agriculture using a choice experiment. The results show a significant willingness to pay for services such as drought mitigation, water quality and the environment and maintenance of rural lifestyles and rice landscapes. The iterative procedure developed to fully analyze the incidence of attribute nonattendance (ANA) improved the model fit when compared with a multinomial logit model or an ANA model with potentially only one attribute ignored at a time (ANA‐1). Moreover, the inferred probability of the class of respondents having attended all attributes was 45%, compared to 9% with ANA‐1 model. However, it also suggests that 55% of the respondents made their choices by considering only two of the five attributes. Finally, this research also suggests that failing to consider ANA does not change the public ranking of scenarios contrasted by the services they would provide but would overestimate the WTP for these scenarios.  相似文献   

14.
    
Agrobiodiversity can provide natural insurance to risk‐averse farmers by reducing the variance of crop yield, and to society at large by reducing the uncertainty in the provision of public‐good ecosystem services, for example, CO2 storage. We analyze the choice of agrobiodiversity by risk‐averse farmers who have access to financial insurance, and study the implications for agrienvironmental policy design when on‐farm agrobiodiversity generates a positive risk externality. While increasing environmental risk leads private farmers to increase their level of on‐farm agrobiodiversity, the level of agrobiodiversity in the laissez‐faire equilibrium remains inefficiently low. We show how either one of the two agrienvironmental policy instruments can cure this risk‐related market failure: an ex ante Pigouvian subsidy on on‐farm agrobiodiversity and an ex post payment‐by‐result for the actual provision of public environmental benefits. In the absence of regulation, welfare may increase rather than decrease with increasing environmental risk, if the agroecosystem is characterized by a high natural insurance function, low costs, and large external benefits of agrobiodiversity.  相似文献   

15.
    
Perennial energy crops are a promising source of bioenergy whose production involves production risks, long‐term commitment of land and need for crop‐specific investments without the coverage of crop insurance potentially available for conventional crops. We conduct a choice experiment in five states in the Midwestern and South‐central regions of the U.S. to examine the effect of crop‐contract attributes on the joint discrete‐continuous choice decisions to adopt an energy crop and convert acres to it from a status quo use, while controlling for the effect of various farmers’ risk and time preferences, sociodemographic characteristics, and availability of crop insurance for conventional crops. We find robust evidence that high discount rates, high upfront establishment costs and need for crop‐specific investments create disincentives for adoption and allocation of land to energy crop production. The effects of riskiness of returns and risk aversion are less robust across specifications. The effect of conventional crop insurance on the energy crop adoption decision differs across types of insurance; in particular, farmers with revenue insurance are statistically significantly less likely to adopt an energy crop. Our results have implications for the design of effective contracts and policy incentives to induce the production of energy crops.  相似文献   

16.
Management of livestock diseases is important in ensuring food safety to consumers in both domestic and export markets. Various measures are prescribed under the Sanitary and Phytosanitary Standards (SPS) agreement of the World Trade Organization. In order to prevent the spread of trans‐boundary cattle diseases, the SPS agreement recommends the establishment of Disease‐Free Zones (DFZs). These have been implemented successfully in some major beef‐exporting countries, but in Kenya are still at a pilot stage. To understand Kenyan farmers’ preferences on the type of DFZ that would be readily acceptable to them, a choice experiment was conducted using a D‐optimal design. Results show that farmers would be willing to pay to participate in a DFZ where: adequate training is provided on pasture development, record keeping and disease monitoring; market information is provided and sales contract opportunities are guaranteed; cattle are properly labelled for ease of identification; and some monetary compensation is provided in the event that cattle die due to severe disease outbreaks. Preferences for the DFZ attributes are shown to be heterogeneous across three cattle production systems. We also derive farmers’ preferences for various DFZ policy scenarios. The findings have important implications for policy on the design of DFZ programmes in Kenya and other countries that face similar cattle disease challenges.  相似文献   

17.
    
We investigate the value of a country of origin label (COOL) that separately identifies the geographic location of different stages in a food product's supply chain. We estimate the willingness‐to‐pay (WTP) of U.S. consumers for a packaged cereal product where the key grain ingredient may be grown in one country and processed in a second country (multicountry supply chain) and compare it to equivalent products that have both stages located in a single country. We find consumer WTP for products with single‐country and multicountry supply chains are statistically different, meaning that simplifying a multicountry label by listing only the country where the ingredients are grown or only the country where the ingredients are processed can result in different consumer values. We also find that for countries with a poor quality reputation, consumers respond more negatively when that country has the “last touch” than when that country's involvement is limited to upstream supply chain links.  相似文献   

18.
    
This paper examines the issue of incentive compatibility within environmental stewardship schemes, where incentive payments to farmers to provide environmental goods and services are based on foregone agricultural income. The particular focus of the paper is land heterogeneity, either of agricultural or environmental value, leading to divergence between the actual and socially optimal level of provision of environmental goods and services. Given land heterogeneity, such goods and services are likely to be systematically over‐ or under‐provided in response to a flat rate payment for income foregone.  相似文献   

19.
    
Industrial mining generally develops in rural areas where agriculture is the main subsistence activity of the population. However, there seems to be an incompatible coexistence between agricultural and mining activities, as both require a large amount of land. Given the extensive agricultural system in Burkina Faso and the expansion of mining since 2007, this study analyzed the effect of industrial mining land use on poverty in the 13 regions of Burkina Faso. The study examined the effect of mining land use intensity on cereal production/yield before exploring its impact on poverty by using several econometric methods and various data from the National Statistics Institute. The results indicate that mining land use intensity had no direct effect on poverty; instead, the effect is indirect. Indeed, mining land use intensity negatively affects cereal yield, and that reinforces the incidence of poverty in mining regions. Moreover, the results show that cereal production increases with cropped land. As cereal yield decreases with industrial mining land use intensity, this suggests that the expansion of mining would contribute to the jeopardizing of the food supply as well as the exacerbation of poverty in mining regions. Therefore, policies are needed to encourage the sustainable management of land and mining revenue redistribution in the mining regions of Burkina Faso.  相似文献   

20.
  总被引:1,自引:0,他引:1  
Groundwater depletion is a serious problem in Mexico. Several policy alternatives are currently being considered in order to improve the efficiency of irrigation water use so that extraction of groundwater is diminished. An understanding and quantification of different sources of inefficiency in groundwater extraction is critical for policy design. Survey data from a geographically extensive sample of irrigators is used to gauge the importance of common pool problems on input‐specific irrigation inefficiency. Results show that mechanisms of electricity cost sharing implemented in many wells have a sizable impact on inefficiency of irrigation application. Moreover, irrigation is very inelastic to its own unitary cost. Therefore, results suggest that policies aimed at eliminating electricity cost‐sharing mechanisms would be significantly more effective than electricity price‐based policies in reducing irrigation application. Results also show that well sharing does not affect groundwater pumping significantly, suggesting either a limited effect of individual pumping on water level or absence of strategic pumping by farmers sharing the wells.  相似文献   

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