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1.
Growth trends of animal farming pose a threat to water quality around the world. To find cost‐efficient means to reduce nutrient loads from agriculture, detailed information on the abatement measures need to be incorporated in bioeconomic models. This study presents a theoretical framework that covers both animal and crop operations on farms. It describes the farmer decision making problem and incorporates nonlinear functions to capture the economic and biological aspects of the problem. The model is applied to Finnish dairy farms. The abatement cost functions are derived for nitrogen and phosphorus. Results indicate that abatement measures on fields should precede dietary changes.  相似文献   

2.
On June 2003 the final version of the Common Agricultural Policy Mid‐Term Review (CAP MTR) was published. The driving forces of this policy change include inter alia the compliance with World Trade Organization (WTO) negotiations' requirements, improvement of social support for agricultural policy, adjustment to budget constraints and adaptation of agricultural practices to environmental requirements. This article reviews how this policy performs in marginal areas regarding one of those objectives: the provision of environmental outputs related to agricultural activity. As an alternative to this reform, a policy based on agri‐environmental measures designed to maximize environmental outputs, is proposed. Both options are evaluated from a cost‐effectiveness point of view. Data from a farm survey and a positive mathematical programming model for a cereal steppes agro‐system in Spain are combined in order to simulate the effects of this reform and our alternative instrument on several environmental indicators. Results show that in marginal areas, where land abandonment is a clear threat, more environmental output can be achieved for the same cost, while maintaining, if not increasing, the levels of achievement for the other goals.  相似文献   

3.
A previous study developed a framework for choosing among groups of policy mechanisms for encouraging environmentally beneficial land-use change. The framework highlights that these choices should depend on the relative levels of private (or internal) net benefits, and public (or external) net benefits. Incentive-based mechanisms (polluter-pays and/or beneficiary-pays) and extension need to be targeted carefully to appropriate projects—where private net benefits are close to zero, and/or public net benefits are more extremely positive or negative. This article focuses on policy mechanisms that alter the net benefits of changing land management, including R&D to develop new technologies, and training to improve the skill of landholders at using existing technologies. These policy options are now treated more comprehensively within the public benefits: private benefits framework. Benefits of technology-change projects can include reductions in the opportunity cost of compliance with environmental programs, increases in the public benefits of a particular type of land-use change, or improvements in private net benefits, resulting in public benefits through greater or more rapid adoption by private landholders. From an environmental management perspective, technology development is most relevant where public net benefits of land use change are positive and private net benefits are negative, but not highly negative. There is a set of projects for which technology change is the only viable alternative to no action, highlighting the importance of technology change in these cases.  相似文献   

4.
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   

5.
The impact of farm credit in Pakistan   总被引:3,自引:0,他引:3  
Both informal and formal loans matter in agriculture. However, formal lenders provide many more production loans than informal lenders, often at a cost (mostly loan default cost) higher than what they can recover. For example, the Agricultural Development Bank of Pakistan (ADBP), providing about 90% of formal loans in rural areas, incurs high loan default costs. Yet, like other governments, the Government of Pakistan supports the formal scheme on the grounds that lending to agriculture is a high risk activity because of covariate risk. Hence, such policies are often based on a market failure argument. As farm credit schemes are subsidised, policy makers must know if these schemes are worth supporting. Using a recent large household survey data from rural Pakistan (Rural Financial Market Studies or RFMS), we have attempted to estimate the effectiveness of the ADBP as a credit delivery institution. A two‐stage method that takes the endogeneity of borrowing into account is used to estimate credit impact. Results reveal that ADBP contributes to household welfare and that its impact is higher for smallholders than for large holders. Nevertheless, large holders receive the bulk of ADBP finance. The ADBP is, thus, not a cost‐effective institution in delivering rural finance. Its cost‐effectiveness can be improved by reducing its loan default cost and partially by targeting smallholders in agriculture where credit yields better results.  相似文献   

6.
In many arid and semi‐arid regions whether or not to desalinate seawater has long been a non‐issue and policy debates are focused on the timing and extent of the desalination activities. We analyze how water scarcity and demand structure, on the one hand, and cost reduction via R&D programs, on the other hand, affect the desirable development of desalination technologies and the time profiles of fresh and desalinated water supplies. We show that the optimal R&D policy is of a non‐standard most rapid approach path (NSMRAP) type, under which the state of desalination technology — the accumulated learning from R&D efforts — should approach a pre‐specified target process as rapidly as possible and proceed along it thereafter. The NSMRAP property enables a complete characterization of the optimal water policy. The renewable nature of the fresh water stock permits a non‐monotonic behavior of the optimal stock process: under certain conditions, the stock is depleted, to be fully or partly) refilled at a later date.  相似文献   

7.
The efficacy and cost of input standards for reducing nitrate pollution from New Zealand dairy production are evaluated. In contrast to previous studies, firm heterogeneity is explicitly considered through the novel integration of efficient techniques for the calibration and decomposition of large optimisation models. Nitrogen fertiliser application should not be targeted by policy given its minor role in determining emissions. In contrast, livestock intensity is an appropriate base for regulation given its strong correlation with pollutant load. Abatement cost increases as stocking rate declines, but this can be offset at low levels of regulation through utilising slack feed resources to improve per‐cow milk production. Both uniform and differentiated input standards based on livestock intensity achieve substantial decreases in pollutant load at moderate cost. However, because of disparity in the slopes of abatement cost curves across firms, a differentiated policy is more cost‐effective at the levels of regulation required to achieve key societal goals for improved water quality.  相似文献   

8.
Evaluating the impact of rising fertilizer prices on crop yields   总被引:3,自引:0,他引:3       下载免费PDF全文
Because of tensions on fossil energy and phosphorus markets, the rise in fertilizer prices observed during the last decades may continue in the future, putting into question production pathways relying heavily on crop intensification. To evaluate how, in this context, economic choices may alter crop yields, we first construct different fertilizer price scenarios to 2050 based on an econometric relation with oil and gas prices. Other possible scenarios, such as the continuation of historical trends, are also considered. The resulting changes in fertilizer price range between +0.8% and +3.6% per year over the 2005–2050 period. These scenarios are tested in a global land‐use model incorporating an endogenous representation of the land–fertilizer substitution. We find that the supply‐side response to rising fertilizer prices could lower crop yields in 2050 from ?6% to ?13%, with a corresponding increase in global cropland area ranging between 100 and 240 Mha if the demand for food and nonfood products has to be met. The sensitivity of these results is tested with regard to assumptions on food consumption, change in potential yield and nutrient use efficiency.  相似文献   

9.
The rapid growth of biofuels production, particularly in the United States, the EU, and Brazil, has had important implications for the global livestock industry—both by raising the cost of feed grains and oilseeds and by forcing onto the market a large supply of biofuel by‐products, most of which end up in livestock feed rations. This article investigates the impact of an expanding biofuels industry on the mix and location of global livestock production. Surprisingly, we find that growth in the U.S. and EU biofuels industries results in larger absolute reductions in livestock production overseas than in those regions, due to the international transmission of grains prices which is offset locally by the lower cost of by‐products. We also find that nonruminant production is cut more than ruminant livestock, because it is less able to use biofuel by‐products in its feed rations. Implementing biofuel mandates increases cropland area, a large portion of which is estimated to come from reduced grazing lands. The biofuel producing regions are expected to reduce their coarse grains exports and increase imports of oilseeds and vegetable oils, while they increase their exports of processed feed materials. In sum, biofuel mandates have important consequences for livestock as well as crops, with net effects influenced by the important role of by‐products in substituting for feedstuffs.  相似文献   

10.
Cropland use is experiencing an intense transition in both depth and breadth with rapid development of the Chinese economy. Unwarranted land use transitions can affect the ecosystem services value (ESV) and ecosystem functions significantly. This paper reports the dynamic patterns of cropland transition (CLT) and its impact on ESV in Jiangsu Province based on land-use data from 1990, 2000, 2010, and 2013, crop yield data, empirical data related to ESV, some revisions adapted to the situation of Jiangsu, and Geo-information Tupu methods. Jiangsu has experienced rapid economic growth and urbanization, which can be seen as a microcosm of China's development. Results showed that the total area of cropland decreased markedly from 1990 to 2013. This loss of cropland took place mainly through the expansion of construction land and water area, accounting for 83.78% and 13.71%, respectively. The gain in cropland came mainly from construction land, water area, grassland, and woodland, accounting for 58.92%, 19.92%, 11.46%, and 10.22%. The transitions from 2000 to 2010 were much more significant than during 1990–2000 and 2010–2013. CLTs were accompanied by relatively concentrated distributions near towns and cities and the distributions in southern and central Jiangsu were more than in northern Jiangsu. Between 1990 and 2013, CLTs gave rise to a decrease of 6.78 million US$ ESV that was mostly caused by the transition from cropland to construction land and water area to cropland. Based on this information, some of the major implications for improving the land use policy and ecological protection policy in China were discussed. These include increased emphasis on land quality and ecological environment in balance between cropland addition and conversion, introducing ESV measures to evaluate the ecological effect of land-use planning, and establish an all-around ecological compensation mechanism.  相似文献   

11.
This article illustrates a statistical approach for deriving farm economic impacts of policy options aiming to reduce nitrate diffuse pollution. Building upon Fezzi et al. (2008) , who assess the costs of Water Framework Directive‐related measures on farm accounts data, we estimate regression models allowing such costs to be predicted for any region for which land use patterns and livestock numbers are known. We derive economic impacts in terms of changes in farm gross margin for (a) reducing inorganic fertilizer application, (b) reducing livestock stocking rates, and (c) converting arable land to ungrazed grassland. A case study of the agriculturally diverse Yorkshire Derwent catchment, in the North of England, demonstrates the overall approach. In addition, for this illustration, we combine these cost estimates with prediction of the water quality changes arising from each measure, derived via an integrated hydrological model of the Derwent. This allows a comparison of cost‐effectiveness. Finally, we implement our spatially explicit approach to target the measures to specific subcatchments identified as being of particular environmental policy interest.  相似文献   

12.
河北粮食生产可持续发展策略研究   总被引:1,自引:0,他引:1  
河北粮食生产主要受到社会重大变革、政策调整、农业生产条件、农资投入、科技进步、价格变动等因素的综合影响,单产比播种面积对总产的影响更大。分析了河北省粮食生产发展的制约因素:耕地减少、水资源短缺和成本、效益限制。分析粮食增产潜力,文章认为应以农用水资源为主的农业生产条件合理确定河北省粮食生产品种结构与布局以及粮食产量目标。提出应在基本粮田保护区设立、中低产田、水利建设与节水、优良品种及农业科技等方面着力加强。同时在耕地流转、政府投入、种粮补贴等方面也应配套政策措施。  相似文献   

13.
This article addresses the challenge of developing a ‘bottom‐up’ marginal abatement cost curve (MACC) for greenhouse gas (GHG) emissions from UK agriculture. An MACC illustrates the costs of specific crop, soil and livestock abatement measures against a ‘business as usual’ scenario. The results indicate that in 2022 under a specific policy scenario, around 5.38 Mt CO2 equivalent (e) could be abated at negative or zero cost. A further 17% of agricultural GHG emissions (7.85 Mt CO2e) could be abated at a lower unit cost than the UK Government’s 2022 shadow price of carbon [£34 (tCO2e)?1]. The article discusses a range of methodological hurdles that complicate cost‐effectiveness appraisal of abatement in agriculture relative to other sectors.  相似文献   

14.
Changes in agricultural land use have important implications for environmental services. Previous studies of agricultural land‐use futures have been published indicating large uncertainty due to different model assumptions and methodologies. In this article we present a first comprehensive comparison of global agro‐economic models that have harmonized drivers of population, GDP, and biophysical yields. The comparison allows us to ask two research questions: (1) How much cropland will be used under different socioeconomic and climate change scenarios? (2) How can differences in model results be explained? The comparison includes four partial and six general equilibrium models that differ in how they model land supply and amount of potentially available land. We analyze results of two different socioeconomic scenarios and three climate scenarios (one with constant climate). Most models (7 out of 10) project an increase of cropland of 10–25% by 2050 compared to 2005 (under constant climate), but one model projects a decrease. Pasture land expands in some models, which increase the treat on natural vegetation further. Across all models most of the cropland expansion takes place in South America and sub‐Saharan Africa. In general, the strongest differences in model results are related to differences in the costs of land expansion, the endogenous productivity responses, and the assumptions about potential cropland.  相似文献   

15.
16.
Lessons from a variety of past and present US cropland diversion programmes are important for evaluating UK set-aside proposals. The structure and operation of current US programmes and the major UK proposals are described. A comparative economic welfare analysis of generic cropland diversion in the US and UK reveals the different types of potential impacts due principally to their different agricultural support programmes. Government cost savings and land rental payments can be misleading benefit and cost indicators for set-aside. Major problems with US programmes include slippage of production control, lack of targeting, inadequate overall efficiency evaluations, and goal conflict. The most appropriate role for cropland diversion may be as a compensatory mechanism to aid the agricultural adjustment process in the face of price restraint, while securing the most valuable non-market conservation and environmental services from idled farm land.  相似文献   

17.
Informal land transactions, particularly rental land markets, are emerging in rural Ethiopia in response to the inadequacies of the administratively based land distribution system to meet the growing demand for land and correct imbalances in factor proportions at the farm level. These informal land markets provide a vehicle to equalise factor proportions at the farm level and to improve productivity and hence households' welfare. Among the farmers who lease out land, those who live in the highland‐areas, where land is scarce and unequal, are more likely to engage in these markets. Increases in the size of land holdings relative to labour and livestock ownership, the number of non‐working household members and pressure for subsistence increase the likelihood of leasing out land. On the other hand, increases in the number of working adults, improved nutritional status and greater wealth affect negatively the supply of land into these markets. The potential exists for these markets to improve factor equalisation, reduce inequality in land holdings, and shift the income position of participating households. However, success depends on whether other factor markets are functioning to thwart forced disposal of land to meet subsistence. Public policy has pivotal role in fostering the growth of these markets and their land transfer and factor equalisation functions by ensuring their legally enforceable status, and removing legal restrictions that constrain choices of contracts and trading over greater distances. In addition, both long and short‐term policy measures are needed to reduce the extent to which poor farmers engage in distress transactions.  相似文献   

18.
Investments in agricultural research and development (R&D) made over the next few decades will likely prove critical in offsetting adverse climate change impacts on the global food system. In this study, we offer cost estimates of public R&D-led adaptation to climate change grounded in an explicit framework relating the flow of annual R&D expenditures to building knowledge capital and thereby raising productivity in agriculture. Our research uses a comprehensive collection of historical public agricultural R&D expenditure and a literature review of elasticity estimates linking knowledge stocks to agricultural productivity growth for key world regions. Given climate-driven crop yield projections generated from extreme combinations of crop and global circulation models, we find that offsetting crop yield losses projected by climate and crop models over 2006–2050 would require increased R&D adaptation investments of between $187 billion and $1,384 billion (in 2005 $PPP) if we invest between 2020 and 2040. This is 16–118% higher than global R&D investment if present spending trends continue. Although these costs are significant, worldwide R&D-led climate adaptation could offer favorable economic returns. Moreover, R&D-led adaptation could deliver gains in food security and environmental sustainability by mitigating food price increases and slowing cropland expansion.  相似文献   

19.
This work provides evidence on the determinants, cost differentiation, and development of short‐term marginal costs of dairy farms in important production regions of the European Union. The empirical study is based on the estimation of multi‐input multi‐output Symmetric Generalized McFadden cost functions using an unbalanced panel data set of the European Farm Accountancy Data Network. The results show considerable regional differences in the impact of the outputs, input prices, and fixed factors on marginal costs. Strong evidence can be found that marginal costs decrease over time and is further underlined by the development of derived regional aggregated short‐term supply curves. Marginal cost elasticities and correlation coefficients validate the hypotheses that a high degree of farm specialization, large milk output, and low milk prices are associated with lower marginal costs. Furthermore, the marginal cost spread in the data sample is analyzed. We show that milk output, milk yield, herd size, labor input, and fodder production can be attributed to significant marginal cost differentiation of farms, whereas for crop and animal output, grassland, stock of other animals, and depreciation only minor differentiation can be found.  相似文献   

20.
Spot water markets and risk in water supply   总被引:1,自引:0,他引:1  
Water availability patterns in semiarid regions are typically extremely variable. Even in basins with a highly developed infrastructure, users are subject to unreliable water supplies, incurring substantial economic losses during periods of scarcity. More flexible instruments, such as voluntary exchanges of water among users, can help users to reduce risk exposure. This article looks at the effects of spot water markets on the economic risk caused by water availability variations. Our theoretical and empirical risk analyses are based on the random profits of water users. Profit probability density functions are formally and graphically characterized for both water sellers and buyers under several possible market outcomes. We conclude from this analysis that, where water supply is stochastic, water markets unambiguously reduce both parties' risk exposure. The empirical study is conducted on an irrigation district in the Guadalquivir Valley (Southern Spain), where there is a high probability of periods of extreme water scarcity. Water demand functions for the district representative irrigators and a spatial equilibrium model are used to simulate market exchanges and equilibrium. This programming model is combined with statistical simulation techniques. We show that the profit probability distribution of a representative irrigator is modified if water exchanges are authorized, leading to risk reductions. Results also indicate that if the market were extended to several districts and users that are subject to varying hydrological risk exposure, extremely low‐profit events would be less likely to occur. In sum, we show that exchanging water in annual spot markets can reduce farmers' economic vulnerability caused by water supply variability across irrigation seasons. These results support the water policy reform carried out in Spain in 1999 to allow for voluntary water exchanges among right holders.  相似文献   

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