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1.
Pesticide productivity,host-plant resistance and productivity in China   总被引:2,自引:0,他引:2  
Pesticides are used as the primary method of pest controf in Asian rice production. Conditions in China have led to demand for high and increasing rice yields, resulting in intensive cultivation and adoption of fertilizer responsive varieties. The consequence has been widespread pest infestations. Many studies have estimated pesticide productivity, but few have estimated the productivity of alternative methods ot pest control, namely host-plant resistance. None have estimated the substitutability between these methods of pest-control. The productivity of pesticides and host-plant resistance, and the substitutability between them is measured using two-stage Cobb-Douglas and translog production functions. Under intensive rice production systems in eastern China, pesticide productivity is low compared to the productivity of host-plant resistance. In fact, returns to pesticide use are negative at the margin. Host-plant resistance is an effective substitute for pesticides and substantial reductions in pesticide use could be achieved, with no loss in rice production, through improvements in host-plant resistance. These results suggest that pesticides are being overused in eastern China and host-plant resistance is being underutilized. Government policies to promote increased pesticides in rice might be ill advised given the low productivity and negative returns, particularly in light of well known negative externalities associated with pesticide use.  相似文献   

2.
This study investigates how pesticide use by neighbouring farmers affects a given farmer's pesticide use. Although it is common knowledge that pesticide use has spatial externalities, few empirical economic studies explicitly analyse this issue. Applying a spatial panel econometric model to plot‐level panel data for Bohol, Philippines, this study shows that pesticide use, especially for herbicides, is spatially correlated, although there is no statistically significant spatial correlation in unobserved shocks. This implies that farmers apply pesticides by referring to the behaviour of neighbouring farmers rather than responding directly to the intensity of their own infestation.  相似文献   

3.
Theoretical and applied literature on risk in decision making for agricultural pest control is reviewed. Risk can affect pesticide decision making either because of risk aversion or because of its influence on expected profit. It is concluded that risk does not necessarily lead to increased pesticide use by individual farmers. Uncertainty about some variables, such as pest density and pest mortality, does lead to higher optimal pesticide use under risk aversion. However, uncertainty about other important variables, such as output price and yield, leads to lower optimal levels of pesticide use. Neglect of these variables in most studies has led to the false assumption that pesticides are always risk-reducing inputs. Furthermore, there is evidence that, in general, the pesticide dosage which maximises expected profit is lower under risk than under certainty. Depending on the balance of forces to increase and decrease pesticide use under risk, in many circumstances the net effect of risk on optimal decision making for pest control may be minimal. The effect on risk of information about pest density and other variables (as in integrated pest management programmes) is discussed. Evidence on this issue is mixed. A range of analytical techniques for analysing risk in pest control is reviewed. Throughout the paper, gaps in the existing literature are identified.  相似文献   

4.
[目的]农药作为蔬菜生产中主要的投入品,在杀虫灭菌、控草护田、生长调节等方面发挥着重要作用,对于保障蔬菜供给意义重大。但是在设施蔬菜种植过程中,由于不合理、过量施用农药导致出现部分蔬菜产品农残超标、农药污染农田生态环境等问题,推进农药减施刻不容缓。[方法]文章运用SWOT分析方法研究寿光市设施蔬菜种植中减施农药的内外部条件,根据有利因素和不利因素调整发展思路,改善农药的不合理使用现状。[结果]通过分析发现,寿光市设施蔬菜种植中减施农药的优势是资源条件好、农户蔬菜种植经验丰富、安全用药意识高;劣势是病虫害抗药性渐强、农户传统的用药习惯根深蒂固且减施农药意愿低;机遇是消费者的需求升级、科学技术水平提高以及相关减施政策实施;挑战是当前市场竞争激烈且政府监管欠佳。[结论]推进设施蔬菜农药减施应采取以下对策:(1)统防统治与绿色防控技术并举,保障蔬菜的质量安全和生物多样性的发展;(2)提升意识与科学用药并重,促进当地蔬菜生产稳定发展;(3)政府监管与信息共享统筹,规范农资市场和农产品市场的交易行为;(4)农业保险与农业补贴兼顾,建立起适度超前、开放灵活政策保障体系。  相似文献   

5.
Chemical pesticides constitute an important input in crop production. But their indiscriminate use can impact negatively agricultural productivity, human health, and the environment. Recently, attention is focused on the use of economic incentives to reduce pesticide use and its related indirect effects. The aim of this work is to assess the effectiveness of different economic instruments such as taxes and levies in encouraging farmers to decrease pesticide use and their environmental spillovers. A policy simulation model is employed using data from Dutch cash crop producers including two pesticide categories that differ in terms of toxicity and pesticides’ environmental spillovers. Four different instruments were selected for evaluation: pesticide taxes, price penalties on pesticides’ environmental spillovers, subsidies, and quotas. The results of the study indicate that even high taxes and penalties would result in a small decrease in pesticide use and environmental spillovers. Taxes that differentiate according to toxicity do not lead to substitution of high‐ with low‐toxicity pesticides. Subsidies on low‐toxicity products are not able to affect the use of high‐toxicity products. Pesticide quotas are more effective in reducing pesticide use and environmental spillovers.  相似文献   

6.
There is an increasing policy interest in pesticide taxation schemes as a measure to reduce harmful effects of pesticide use. The effectiveness of such tax depends, however, on the price elasticity of demand for pesticides. Moreover, information on these demand elasticities and their determinants is of crucial relevance for policy‐making and normative modeling approaches. In this article, we present a meta‐analysis based on studies that have estimated pesticide demand elasticities in Europe and North America. Our meta‐analysis reveals that the own‐price elasticities of demand for pesticides are, with a median of ?0.28, significantly smaller than zero, but also significantly larger than ?1, i.e. to be inelastic. We find that the demand for pesticides for special crops is less elastic than that for arable and grassland. In addition, the demand for herbicides is more elastic than for other pesticides. Studies that consider only short‐term horizons and little flexibility for farmers to adjust to price changes generate significantly less elastic pesticide demands. The results also indicate that more recent studies identify lower pesticide price elasticities of demand. Furthermore, we find that peer‐reviewed studies tend to find more inelastic results compared to grey literature.  相似文献   

7.
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   

8.
Abstract

A nonlinear, partial equilibrium, Armington model of the European Union canned pear market was built and simulated for reductions in specific EU policies and for reductions in selected combinations of these policies relevant to canned pears: import tariffs, factor subsidies, and an output subsidy. Effects of these policy reductions on the following EU canned pear market variables were comparatively analyzed: own-product consumption, imports, exports, and price. Comparative analyses of these policy-specific effects were conducted from two viewpoints: the absolute magnitudes of completely eliminating, and the marginal effects of incrementally reducing, the EU policies and policy combinations. Among other findings, results suggest that EU tariff reduction enhances EU imports more than EU subsidy reduction, and that EU subsidy reduction increases EU prices more effectively than reducing EU tariffs.  相似文献   

9.
The lengthy debate on appropriate public policy for agricultural land planning has had two major components: the regulation of severances of farmland and the orderly expansion of each growing city. Putting aside the latter issue, this paper reports research on the severance issue, which is perhaps the key controllable socio-economic policy variable in rural foodland protection. This paper examines data from one of the most complex areas, the intermediate rural fringe surrounding Toronto. A “severance theory” is presented, based upon a review of theories of externalities and land economics. To test the severance theory, a regression model is used. The research provides what may be the first quantitative information in North America on the extent of the pecuniary externalities alleged to arise from severances, and hence provides some of the information that would be required to evaluate empirically proposed and existing land use policies. The severance theory predicts that severance activity would increase the price of nearby farmland. From the statistical analysis, it is concluded that severances did affect farmland values but that the relationships were more complex than anticipated. Severances influenced farmer buyers to pay higher prices for farmland. However, the predominating nonfarm buyer of farmland in York Region consistently reacted as if there were negative externalities from severances and paid lower prices where severances had an influence. The implications of this study for public policies such as the Ontario Food Land Guidelines are limited by the study area and time period examined. The approach used in this study should be applied to other areas, especially ones less subject to purchases by nonfarmers, in order to define more precisely the impact of severance activity on nearby farmland values.  相似文献   

10.
11.
In this paper we present results from two choice experiments (CE), designed to take account of the different negative externalities associated with pesticide use in agricultural production. For cereal production, the most probable impact of pesticide use is a reduction in environmental quality. For fruit and vegetable production, the negative externality is on consumer health. Using latent class models we find evidence of the presence of preference heterogeneity in addition to reasonably high willingness to pay (WTP) estimates for a reduction in the use of pesticides for both environmental quality and consumer health. To place our WTP estimates in a policy context we convert them into an equivalent pesticide tax by type of externality. Our tax estimates suggest that pesticide taxes based on the primary externality resulting from a particular mode of agricultural production are a credible policy option that warrants further consideration.  相似文献   

12.
The reduction of adverse health and environmental effects from pesticide use is currently a top priority on the agricultural policy agenda. Efficient pesticide policies must take into account farmers’ application behavior, especially effects of pesticide use on economic risk. However, previous results regarding the direction of risk effects of pesticides are ambiguous. We show that the ambiguity in earlier studies could be due to the pesticide indicator selected. Indicators which fail to account for the heterogeneous properties of pesticides may be inapt for interpreting farmers’ pesticide use decisions. Our analysis, based on a rich panel dataset of Swiss wheat producers with highly detailed information on pesticide use, considers different pesticide indicators and multiple sources of uncertainty. Our key finding is that indicator choice affects the magnitude and sign of estimated risk effects. Estimates of pesticide productivity and risk effects are significantly higher for fungicides, and even reversed for herbicides when we measure pesticide use in simple quantity units (kilogram per hectare) - compared to the quality and intensity corrected Load Index. This means for example, that farmers will ceteris paribus use lower quantities of herbicides, but will increase the overall toxicity of the products applied with increasing risk aversion. We discuss implications of our findings for the design of pesticide policies and agricultural risk management instruments.  相似文献   

13.
Stabilization of prices is an important element of food policy in India as in most other countries — both developing and eveloped. However, since the magnitude of grain stocks held for this purpose as well as the costs of physical storage have become prohibitively high, there is now a need for finding cost-effective alternatives including non interventionist and market-oriented methods for price stabilization. In this paper we consider the case of rice and wheat which are staple foodgrains in India. We make a comparison between alternative price stabilization policies including that of holding buffer stocks in terms of their impact on domestic price stability, producer and consumer welfare and government costs. A multi-market equilibrium framework is used where private storage, consumption, supply and prices of rice and wheat are determined simultaneously. Indian exports and imports are assumed to affect world prices. The alternative price stabilizing mechanisms are ranked according to both the criteria, welfare and price stability achieved. The main findings are as follows. The ranking of alternatives varies with the criterion used. Greater price stability need not necessarily imply greater welfare. The option of variable levies on private external trade turns out to be the most inexpensive and that of domestic buffer stocks the costliest in achieving price stability. Further, the efficacy of buffer stocks and subsidy to private storage in stabilizing prices is lower under free trade as compared to the case where the economy is closed to private external trade.  相似文献   

14.
Many low-income countries pursue cheap-food policies in which consumers pay subsidized prices for bread, rice and other staples. This paper addresses the issue of why different governments select different food subsidy policies, using multiple instruments rather than a simple across-the-board subsidy to provide consumers with access to cheap food. It examines the optimal structure of cheap-food policies in the context of a partial equilibrium model in which the country may he large in trade, and is able to combine import subsidies or tariffs, and output taxes or subsidies, to transfer income to consumers through the market. The model allows for a marginal opportunity cost of government revenues greater than one dollar. In addition, in the model, food aid from overseas may be either given away to the consumer, or given to the government for subsequent sale in the domestic market. The results indicate that only by happenstance will a country choose to use a pure consumption subsidy or a pure import subsidy to transfer income to consumers. In addition, an increase in international food aid does not necessarily lead the government to reduce producer and consumer prices for a commodity.  相似文献   

15.
Livestock pricing policies in many developing countries are often instituted without a good appreciation of the consequences of such policies for allocative efficiency, output and trade. This paper evaluates, in a comparative cross-country context, the objectives and instruments of livestock pricing policy in five sub-Saharan African countries: Ivory Coast, Mali, Nigeria, Sudan and Zimbabwe during the period 1970-86. It assesses the extent to which pricing policy objectives have been attained, and also estimates the effects of price interventions on output, consumption, trade and government revenues in order to draw out lessons for the future. The empirical results indicate that in comparison with real border prices, a certain degree of success was achieved in stabilising real domestic producer prices in the study countries. The results also show that since the early 1980s, there has been a gradual shift away from taxation of producers. However, consumers still appear to gain as much as producers in three of the study countries, with negative consequences for foreign exchange earnings and government revenues. The analysis reveals the importance of domestic inflation and exchange rates as key variables for livestock pricing policies and highlights the need to address the macroeconomic imbalances that cause exchange rate distortions and high domestic inflation at the same time that direct price distortions are being tackled.  相似文献   

16.
研究目的:考察政府不同干预行为对农地经营权流转价格扭曲的影响效应,为完善农地生产要素配置及优化农地市场内外环境等提供政策建议。研究方法: Binary Logistic模型。研究结果:(1)当前农地经营权流转价格本应反映承包地利用产生的经济效益,由土地要素投入产出品的边际收益价值所决定;但受市场机制不完善、乡土伦理规范等多重影响,农地实际流转价格与要素价格间产生差异,表现为农地经营权流转价格扭曲。(2)政府不同的干预行为对农地经营权流转价格扭曲产生差异化效应。政府主导流转的直接干预模式会引起流转价格的高价扭曲,而通过构建流转交易平台、提供补贴等政策间接干预会缓解流转价格的低价扭曲。(3)对土地的经济诉求和保障诉求是造成流转价格扭曲的重要原因。研究结论:农地经营权流转价格的形成应交予市场,政府应避免直接干预造成价格的人为扭曲,可通过土地流转中介组织或补贴政策来间接培育优化农地市场交易环境。  相似文献   

17.
The energy crisis and the current world food situation have both drawn attention to the importance of off-farm inputs in high-technology agricultural systems. Plant pesticides are one of the most important of these off-farm inputs. The correct use of chemical pesticides requires a high level of managerial competence since the issues involved are extremely complex. The development of an integrated approach to the management of plant pests offers an alternative to the increasingly expensive chemical control techniques. Cotton production illustrates both the complexities of the management involved in plant pest control and the feasibility of developing integrated control strategies. Plant pesticides, especially insecticides, also create externalities. The policy issues surrounding the use of cotton insecticides demonstrates the need for careful analysis before political action is taken. A feasible package of policy measures for the control of the use of insecticides in Australian cotton-growing areas is suggested.  相似文献   

18.
Decomposing changes in agricultural price gaps: an application to Russia   总被引:1,自引:0,他引:1  
The article develops a method for decomposing changes in agricultural price gaps, defined as the difference between a commodity's domestic producer and border prices. We use OECD's procedure for decomposing changes in the market price support part of producer support estimates as the starting point for our decomposition method, and our method provides a basis for critiquing OECD's decomposition approach. The transmission of changes in border prices (world prices and the exchange rate) to domestic prices is a key element in the decomposition. The method is demonstrated using Russian agricultural price gaps. The results support the argument that for Russian agriculture during the transition period, the main cause of changes in price gaps has been incomplete transmission of changes in the exchange rate to domestic prices, and where the weak transmission results mainly not from policy intervention, but rather from deficient market conditions, in particular poor market infrastructure. The policy implication is that underdeveloped infrastructure has strongly limited the benefits to the Russian economy from agricultural trade liberalization.  相似文献   

19.
The implication of price stabilisation under a volatile exchange rate is an increasingly volatile price denominated in a foreign currency. Time series analysis is used to model the relationship between exports, prices and AWC stocks. This model is used to assess the distribution of the impact of exchange rate shocks on prices denominated in local and foreign currencies. It is found that the AWC has significantly reduced the impact of exchange rate shocks on domestic prices.  相似文献   

20.
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