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1.
This paper integrates economic and physical models to assess: a) how increases in agricultural commodity prices, driven by ethanol production and other factors, affect land use and cropping systems in the US Midwest, and b) how the changes in land use and cropping systems in turn affect environmental quality in the region. The empirical framework includes a set of econometric models that predict land conversion, crop choices, and crop rotations at the parcel level based on commodity prices, land quality, climate conditions, and other physical characteristics at the sites. The predictions are then combined with site-specific environmental production functions to determine the effect of rising commodity prices on nitrate runoff and leaching, soil water and wind erosion, and carbon sequestration. Results suggest that increasing commodity prices will result in widespread conversions of non-cropland to cropland. Fifty percent of the region’s pasture and range land will be converted to cropland with 6 corn. Rising commodity prices will also result in dramatic changes in crop mix and rotation systems in the Midwest. With6 corn. Rising commodity prices will also result in dramatic changes in crop mix and rotation systems in the Midwest. With 6 corn, the total acreage of corn will increase by 23% and 40% in the Corn Belt and Lake States, respectively; the acreage of continuous corn will increase considerably in both regions as well. These changes in land use and crop mix will have a large impact on agricultural pollution. Approaches to mitigating the environmental impacts are discussed.  相似文献   

2.
Crop rotation and other input management practices are of particular interest for their potential impacts on economic and agro-environmental components of potato production. Although crop yield and experimental impacts of rotations of grains, oilseed and legume crops have been published for several experimental studies in Canada there are few models related to the economic and environmental dynamics of potato production. We describe a dynamic model which integrates environmental and economic processes in potato production. The potato rotation model consists of interconnected modules of irrigation and precipitation, soil characteristics, soil erosion, soil water, phosphorus, nitrogen, soil organic matter, farming operations, crop yield and the related calculation of economic return. While not all aspects of crop production have been interlinked, including nitrogen carry-over, this model is the first step in the analysis of experimental data for irrigated potato rotations conducted in southern Manitoba.   相似文献   

3.
This article examines the output price effects on the US crop production, employing an ex-ante approach to the differential systems of input demand and output supply. The estimation results of the differential input demand show that the expansion of crop production leads to an increase in acreage (i.e. extensive margin) and a proportional rise in input usage improving yield per acre (i.e. intensive margin). The substitutable relationship between fertilizer and land supports that crop producers have an option to choose either intensive or extensive margin in response to changes in their relative prices. In addition, the estimation results of the differential output supply highlight that the composition of crop supply can be altered by changes in ex-ante crop prices. The estimation results suggest that crop producers substitute corn supply for the supply of cotton, wheat and soybeans or vice versa. Based on the estimated elasticities, the decompositions of profit-maximizing input demand are conducted, which reveals that a change in ex-ante crop prices is associated closely with resource reallocation.  相似文献   

4.
Soil erosion is one of the most important of today’s environmental externalities and a major threat to sustainability of agricultural system. It constitutes the most widespread forms of land degradation throughout the world. The aim of this paper is to estimate the amount of soil erosion generated by the current cropping systems in Tunisia and to assess the economic and ecological impacts of policy instruments designed to handle this problem. The analysed policy options are based on soil conservation practices and direct incentive farming anti-erosive measures. The selected measures are the reduction of tillage, the avoidance of bare fallow and the use of legume-based crop rotation. A bio-economic modelling framework coupling the biophysical model EPIC to a non-linear dynamic programming farm model was used for this impact analysis. It was performed in a set of representative farms belonging to a region in North-Eastern Tunisia (Zaghouan) strongly affected by this phenomenon. The main finding of this research is the non-convexity of the crop yield—soil erosion space. That is, the use of more intensive techniques to increase productivity (i.e. crop yield) may be accompanied by rough changes in soil erosion (damage) curves, manifested either by non-monotony or non-convexity. In term of policy options and because of giving up convexity assumptions, incentive anti-erosive measures appear more efficient than conventional environmental policies such as Pigouvian taxes or quota systems. The implementation of soil conservation practices would leads to a net decrease in soil erosion and an increase in farm income. However, with the current interest rate of 7% the possible rise in income is not enough to stimulate farmers to invest on these practices. A maximum rate of 4% would be necessary to make this policy option more effective.  相似文献   

5.
农业生产对长江三角洲农业环境的影响,一直是社会广泛关注的焦点。水稻种植是长江三角洲农业生产的主要方式。以江苏省为例,在田间试验、农户调查和文献收集的基础上,分析了该省主要生态稻作模式的技术特征及其环境和经济效应。调查和分析结果显示:(1)江苏省生态稻作主要有稻鸭共作型(丹阳)、环境友好型(吴江)和沼气复合型(淮阴)三种典型模式;(2)这三种稻作模式在土壤肥力、生态环境和经济效益上存在一定的差异,但均显著高于当地常规的集约化稻作模式。为了进一步促进该区生态稻作模式的发展,以有效的方式减轻长江三角洲地区的农业环境问题,文章就配套政策方面提出了一些建设性建议。  相似文献   

6.
New Zealand (NZ) dairy farms used to be the lowest input and most efficient dairy farms of the world. However, intensification of the traditional pasture-based system has occurred over the last decade and has not always been accompanied by increased efficiency. The purpose of this paper is to produce an updated reference of the eco-efficiency of NZ dairy farm systems and to analyse the implications of intensification on their eco-efficiency. Results for an average NZ dairy farm system were compared with those for three dairy farmlet systems representing a wide range in intensification practices. A low input system (LI) (no N fertiliser, no brought-in feed supplement, stocking rate of 2.3 cows/ha) was compared with an N-fertilised farm system (NF) (170 kg fertiliser-N/ha/year, 3 cows/ha) representing a first level of intensification and with an N-fertilised and maize silage supplemented system (NFMS) (170 kg fertiliser-N/ha/year, 13 t DM maize silage/ha/year, 5.2 cows/ha), representing a possible future intensification option. Their eco-efficiency in terms of milk production and land use was compared using Life Cycle Assessment (LCA) methodology. NZ dairy farm systems rely on favourable temperate climate conditions and long-term perennial ryegrass/white clover pasture, to achieve eco-efficient milk production and land use compared to European systems. However, intensification of NZ dairy farms was shown to be detrimental to their eco-efficiency in terms both of milk production and land use functions and could greatly reduce their advantage compared to European systems. The eco-efficiency of LI was very high whatever the functional unit which is remarkable from an LCA perspective. NF and NFMS had a similar eco-efficiency except for energy use which corresponded to the most critical hot spot of NFMS. All studied NZ systems presented some areas for improvement where some new technologies available for dairy farms might play a promising role in the future. Finally, it should be highlighted that the comparison with European studies based on the literature available needs validation through a more comprehensive study using harmonised methodology and assumptions across countries.  相似文献   

7.
Debdatta Pal 《Applied economics》2020,52(49):5426-5445
ABSTRACT

We explore return spillover from crude oil to ethanol, corn, soybean and wheat on daily data during 17 May 2005–27 June 2018. This study is unique in capturing the time-frequency dynamics of return spillover. We use the frequency-dependent spillover measure that jointly captures information from time and frequency domain. We also identify two endogenous break dates that segregate the study period in three sub-periods. Our results indicate that return spillover from crude oil to ethanol, major feed stocks (i.e. corn and soybean) and food crop (i.e. wheat) is pronounced only in lower frequency band or long-term (more than 1 month). We find that return spillover is stronger only during 2005–2010, i.e. the period of energy and food crisis.  相似文献   

8.
This article considers alternative methods to calculate the fair premium rate of crop insurance contracts based on county yields. The premium rate was calculated using parametric and nonparametric approaches to estimate the conditional agricultural yield density. These methods were applied to a data set of county yield provided by the Statistical and Geography Brazilian Institute (IBGE), for the period of 1990 through 2002, for soybean, corn and wheat, in the State of Paraná. In this article, we propose methodological alternatives to pricing crop insurance contracts resulting in more accurate premium rates in a situation of limited data.  相似文献   

9.
《Ecological Economics》2006,56(4):584-598
This paper presents a case study in which the effects of agri-environmental policy on two Mediterranean-type farming systems, grazing dominant and cropping dominant, are contrasted. Two greenhouse gas abatement policies are examined; an emissions taxation policy and an emissions restrictions policy. The study seeks to determine firstly, how the policy impacts on the farming systems, and from that, how the nature of the farming systems impact on the effectiveness of the policy. It is shown that relative costs of abatement are higher for the grazing-dominant farming system. However, in the absence of technological change to aid abatement, the cost of substitution from high emitting enterprises, such as livestock, to low emitting enterprises, such as crop production, will determine the cost of abatement. For both farming systems the restriction policy is found to be more effective and economically efficient than the taxation policy. The analysis found that crediting trees as carbon sinks can significantly reduce the costs of abatement. At predicted emissions permit prices, trees would be adopted by both farming systems to offset farm greenhouse gas emissions.  相似文献   

10.
The last 10?years have seen tremendous expansion in biofuels production, particularly in corn ethanol in the United States, at the same time that commodity prices (e.g., corn) have experienced significant spikes. While supporters claim that biofuels are renewable and carbon-friendly, concerns have been raised about their impacts on land use and food prices. This paper analyzes how US crop prices have responded to shocks in acreage supply; these shocks can be thought of as a shock to the residual supply of corn for food. Using a structural vector auto-regression framework, we examine shocks to a crop??s own acreage and to total cropland. This allows us to estimate the effect of dedicating cropland or non-crop farmlands to biofuels feedstock production. A negative shock in own acreage leads to an increase in price for soybeans and corn. Our calculations show that increased corn ethanol production during the boom production year 2006/2007 explains approximately 27% of the experienced corn price rise.  相似文献   

11.
Eco-efficiency refers to the ability to produce more goods and services with less impact on the environment and less consumption of natural resources. This issue has become a matter of concern that is receiving increasing attention from politicians, scientists and researchers. Furthermore, greenhouse gases emitted as a result of production processes have a marked impact on the environment and are also the foremost culprit of global warming and climate change. This paper assesses convergence in eco-efficiency in greenhouse gas emissions in the European Union. Eco-efficiency is assessed at both country and greenhouse-gas-specific levels using Data Envelopment Analysis techniques and directional distance functions, as recently proposed by Picazo-Tadeo et al. (Eur J Oper Res, 220:798–809, 2012). Convergence is then evaluated using the Phillips and Sul (Econometrica, 75:1771–1855, 2007) approach that allows testing for the existence of convergence groups. Although the results point to the existence of different convergence clubs depending on the specific pollutant considered, they signal the existence of at least four clear groups of countries. The first two groups are core European Union high-income countries (Benelux, Germany, Italy, Austria, the United Kingdom and Scandinavian countries). A third club is made up of peripheral countries (Spain, Ireland, Portugal and Greece) together with some Eastern countries (Latvia and Slovenia), while the remaining clubs consist of groups containing Eastern European countries.  相似文献   

12.
We use spatial simulation techniques to estimate both cross pollination damages and net producer benefit from genetically modified (GM) oilseed rape under alternative information requirements about individual farmers' cropping plans. Simulations were carried out for two study regions in Germany. The results suggest that, especially in landscapes with small plots, information requirements implemented in most EU Member States may result in inefficient coexistence to the extent that GM farmers lack important information to adjust their cropping plans to non-GM rape farmers' crop choices. We conclude that, in such fragmented landscapes, more comprehensive information requirements which oblige both GM and non-GM farmers to announce their cropping plans can: (1) substantially increase producer benefits, (2) reduce cross pollination damages and dispute and thus (3) contribute to the local diffusion of GM varieties.  相似文献   

13.
This article investigates the efficiency of the temporary certified emission reductions (tCERs) system that attempts to internalize the carbon sequestration function of the forest under the Clean Development Mechanism of the Kyoto Protocol. We find that the regulations creating tCERs partially internalize the carbon sequestration function of the forest. The amount of carbon re-released into the atmosphere, due to timber harvest, and sequestered, after the project period, is not internalized in the private landowner’s decision, which induces shorter rotation intervals than socially optimal. Furthermore, the carbon sequestered during the project is over-credited because credits are counted based on accumulated carbon instead of marginally sequestered carbon, which induces longer rotations intervals. Simulation results for the Philippines and Tanzania show that the difference in social welfare between the tCERs system and a socially optimal policy is only about 2% because of the countervailing effect of the inefficiencies on rotation interval choices.  相似文献   

14.
《Ecological Economics》2006,56(1):89-103
We use the directional output distance function to derive estimates of production inefficiency, shadow prices for polluting outputs, and the associated pollution costs. Using a quadratic functional form for the directional output distance function and data for the U.S. agricultural sector during 1960–1996, we find that the pollution costs (the shadow values) from the runoff and leaching of pesticides are 6% of crop and animal revenues and are highest in the Midwest and lowest in the Western states. If states were to reduce technical inefficiency and operate on the production frontier, pollution costs could be reduced by 7%.  相似文献   

15.
Changes in agricultural production methods have been associated with environmental pressure and a loss of natural habitats. This paper explores the extent to which farmer participation in off-farm work (an increasing phenomenon in most developed countries) changes the intensity of agricultural input use focusing, in particular, on fertilizer and crop protection product use. A sample selection model that accounts for both unobserved heterogeneity between farms and the potential simultaneity between farm operations and hours worked off-farm is estimated for 2,419 farms in England and Wales. The econometric evidence indicates that the input intensity of products which have well-established links to environmental damage can increase as well as decrease. The results suggest that that fertilizer intensity may decline as off-farm labor increases while the use of crop protection per hectare increases as off-farm work increases.  相似文献   

16.
We use farm diary data from Taiwan in the 1920s and 1930s to estimate the impacts of a state‐wide tenancy reform on tenants’ investment in the farmland and production outcome. The reform, commencing in 1922, enhanced the tenure security for the tenants by promoting written contracts that extended tenure length from 1 year to 5–6 years, and by establishing government‐sponsored organizations for dispute settlements. Our estimations rely on a difference‐in‐difference framework, where self‐cultivated farms are used as the control group. We find that the reform encouraged tenants to make investments in the irrigation and drainage system of the farms, which is expected to have long‐lasting benefits for production. The improved irrigation/drainage system led to significant efficiency gains for the farms. In contrast, the reform did not affect tenants’ usage of fertilizer much, which benefits production for only a crop season or a year.  相似文献   

17.
The main purpose of this paper is an examination of the pass‐through interest rate transmission from the wholesale rates (central bank and/or money market rates) to the retail rates (deposit and lending rates) of the banking system. Knowledge of the transmission substantially helps us to calculate the pass‐through interest rate margin or mark‐up in the banking systems under examination (USA, Canada, the UK and the Eurozone). The selection of the wholesale interest rate is also an important part of this pass‐through transmission framework because it is related to the money supply process and therefore the central bank's policy capabilities. In the empirical part, a Johansen (1988) cointegration based error‐correction procedure (ECM‐GE) is implemented for the wholesale interest rate selection. Then an LSE–Hendry general‐to‐specific model (GETS) is applied, for the revelation of the banking sector pass‐through interest rate behaviour. In the empirical part, on the issue of the wholesale interest rate selection, the USA and the Eurozone seem to favour the Money Market rate while the UK and Canada favour the central bank policy rate. The results indicate two types of interest rate pass‐through behaviour, with market structure implication – namely, the US and UK banking systems contrasted with Canada–Eurozone.  相似文献   

18.
One definition of the natural rate is the (time-varying) steady state equilibrium rate. Then the gap is the difference between the actual and natural rates, or the forecastable movement. Although modern business cycle theories study deviation cycles (cycles in the gap), the NBER business cycle reference dates measure classical cycles (cycles in the actual rate) in the US. Measuring deviation cycles requires detrending, and this motivated the invention of the Beveridge–Nelson (B–N) decomposition. This paper considers multivariate detrending, and proposes a Bayesian approach to the multivariate B–N decomposition. An application of the method to US data gives (i) a joint estimate of the natural rates and gaps of output, inflation, interest, and unemployment with reliable error bands, and (ii) the posterior probabilities of positive gap, recession, and revival. These results may help us to identify the four phases of deviation cycles: expansion, recession, contraction, and revival.  相似文献   

19.
This study examines the relationship between crude oil prices, US dollar exchange rates and 30 selected international agricultural prices and five international fertilizer prices in a panel framework. The study uses panel VAR methods and Granger causality tests on panel data sets of agricultural commodity prices (as well as specific agricultural commodity sub-groups) and fertilizer prices with monthly observations of the period from June 1983 to June 2013. The empirical results of the present study indicate that crude oil prices as well as US dollar exchange rates affect international agricultural commodity and fertilizer prices. Furthermore, contrary to the findings of several studies in the literature, the present study supports bidirectional panel causality effects between crude oil prices and international agricultural prices as well as between US exchange rates and international agricultural prices.  相似文献   

20.
Research on the flow of virtual water associated with agricultural crop production and trade has focussed almost entirely on water quantity. It is pertinent to consider and quantify the opportunity costs in terms of reduced water quality associated with crop production. This paper investigates the impacts of water quality on virtual water trading by creating a proxy for water quality impacts by calculating the amount of water required to dilute nonpoint-source agrochemical inputs to relevant water quality guideline values. The quantity of water required for dilution of five agrochemicals (two nutrients; nitrogen and phosphorus and three insecticides; azinphos-methyl, chlorpyrifos and endosulfan) was estimated for five crops in South Africa (maize, wheat, sugar cane, citrus and cotton) and compared to consumption of irrigation water (blue water) and rainfall (green water) for the same crops. Results indicate that the volume of water required for dilution is similar to the total sum of green and blue water required for crop production, but significantly greater than blue water use (irrigation use). For all crops phosphorus losses require greater amounts of water for dilution than for nitrogen, while pesticides result in the greatest water quality use. Estimates of water quality use are based on assumptions for a number of input variables (i.e. fertilizer application rates, percentage loss of agrochemicals from cropped areas). A Monte Carlo analysis (5000 iterations) was run to randomly select input variables from within defined ranges. Water quality use was calculated and expressed as a factor of blue water use. For all crops the average factor indicated that the volume of water required for dilution of all agrochemicals was greater than that required for irrigation. The results of this study clearly indicate that the impacts of agriculture on water quality need to be considered in virtual water trading scenarios. The incorporation of a method to predict impacts on water quality provides a comparative tool which generates a more holistic frame of reference for decision making with regard to impacts on the water resource and virtual water trading.  相似文献   

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