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1.
This article is an economic analysis of reallocating River Murray Basin water from agriculture to the environment with and without the possibility of interregional water trade. Acquiring environmental flows as an equal percentage of water allocations from all irrigation regions in the Basin is estimated to reduce returns to irrigation. When the same volume of water is taken from selected low-value regions only, the net revenue reduction is less. In all scenarios considered, net revenue gains from freeing trade are estimated to outweigh the negative revenue effects of reallocating water for environmental flows. The model accounts for how stochastic weather affects market water demand, supply and requirements for environmental flows. Net irrigation revenue is estimated to be 75 million less than the baseline level for a scenario involving reallocating a constant volume of water for the environment in both wet and dry years. For a more realistic scenario involving more water for the environment in wet and less in dry years, estimated net revenue loss is reduced by 48 per cent to 39 million. Finally, the external salinity-related costs of water trading are estimated at around 1 million per annum, a quite modest amount compared to the direct irrigation benefits of trade.  相似文献   

2.
This paper evaluates the economic worth of forestry projects in the United Kingdom by using two different public sector investment appraisal criteria; the traditional discounted cash flows and the recently-established sum of discounted consumption flows. In the latter, in view of the intergenerational distribution aspect of government projects, the conventional rules are modified, enabling the decision-maker to treat all generations, present and future, in an equitable manner. Forestry is an excellent example to highlight the issue that many public sector investment projects re-distribute income between generations. Its long gestation periods make it obvious that there is more than one generation involved in the venture. In this analysis a one hectare plantation of Sitka spruce, class 20, is considered for a single 50-year rotation. Three different interest rates, 10 per cent test rate of discount, 5 per cent required rate of return, and 3 per cent forestry target rate are used under 4 different assumptions regarding the future price of timber.  相似文献   

3.
In October 2010, the Murray‐Darling Basin Authority (MDBA) proposed that a range of 3000–4000 GL per year, on average, of additional water be made available for the environment in the Murray‐Darling Basin (MDB) to mitigate the effects of what it considers to be inadequate environmental flows. To help quantify the costs of this water reallocation, a hydro‐economic model was constructed based on the 19 regions of the MDB. The model results indicate the following: (i) substantial reductions in surface water extractions of up to 4400 GL per year impose only a moderate reduction on net profits in irrigated agriculture, Basin wide, given competitive water markets, but the effects are much more pronounced in particular regions/catchments and (ii) the costs of the water reallocation are comparable with the amount budgeted by the Australian government to acquire water from willing sellers and increase environmental flows if inter‐regional water trade is unrestricted.  相似文献   

4.
This study computes the eco‐efficiency of high‐yielding variety (HYV) rice production by including an on‐farm environmental damage index (OFEDI) as an undesirable output using data envelopment analysis. It then identifies its determinants by applying an interval regression procedure on a sample of 317 farmers from north‐western Bangladesh. Results reveal that the mean level of the OFEDI‐adjusted production efficiency (i.e. eco‐efficiency) is 89 per cent, whereas ignoring OFEDI adjustment (i.e. with OFEDI = 0) reduces the mean level of efficiency to 69 per cent, implying that the production of undesirable output or on‐farm environmental damage induces an efficiency loss of 20 per cent with significant differences across regions. The proportion of farmers’ income from HYV rice agriculture, land ownership, extension services and socio‐environmental living standard are the significant determinants of improving eco‐efficiency. Policy implications include investments in extension services and land reform measures to increase land ownership, which will synergistically improve eco‐efficiency of HYV rice production in Bangladesh.  相似文献   

5.
It is argued that the ongoing CAP/GATT reforms provide a basis for the introduction of environmental cross-compliance (ECC). ECC enables policymakers to restrict output-related direct support payments to those farmers who comply with specified environmental guidelines aimed at reducing the external damage effects of agricultural production. This paper is an exploratory investigation of ECC and presents the results of a farm-level linear programming analysis of 15 North-West England arable farms. The environmental guidelines, which relate to permanent as opposed to rotational set-aside and to levels of fertiliser use, are widely applicable to the extent that ECC can be implemented as a voluntary policy system. They are clearly effective in achieving policy goals since all but one of the farmers investigated would comply with the full range of restrictions considered. Within this range, gross margins are reduced by up to 10 per cent while area and output of seed crops are reduced by around 22 per cent and 12 per cent respectively. Row crops area and output are more robust, each falling by just under 4 per cent.  相似文献   

6.
This article examines the ecosystem impacts of transgenic Bt cotton technology resulting from reduced chemical pesticide use. Employing unique panel data from smallholder farmers in India, negative environmental and health effects of pesticide use are quantified with the environmental impact quotient (EIQ), with and without Bt technology. An environmentally sensitive dynamic production function is estimated, treating the environmental risk of pesticide toxicity as an undesirable output in the production process. Negative externalities are significantly lower in Bt than in conventional cotton. The reduction in EIQ through Bt technology adoption has increased from 39 per cent during 2002–2004 to 68 per cent during 2006–2008. Bt adoption has also contributed to higher environmental efficiency. Environmental efficiency is influenced by the quality of Bt technology: high‐quality Bt seeds are associated with higher environmental efficiency than lower‐quality seeds.  相似文献   

7.
Governments in Australia are purchasing water entitlements to secure water for environmental benefit, but entitlements generate an allocation profile that does not correspond fully to environmental flow requirements. Therefore, how environmental managers will operate to deliver small and medium‐sized inundation environmental flows remains uncertain. To assist environmental managers with the supply of inundation flows at variable times, it has been suggested that allocation trade be incorporated into efforts aimed at securing water. This paper provides some qualitative and quantitative perspective on what influences southern Murray–Darling Basin irrigators to trade allocation water at specific times across and within seasons using a market transaction framework. The results suggest that while irrigators now have access to greater risk‐management options, environmental managers should consider the possible impact of institutional change before intervening in traditional market activity. The findings may help improve the design of intervention strategies to minimise possible market intervention impacts and strategic behaviour.  相似文献   

8.
The potential for improving irrigation scheduling decisions and adoption of more efficient irrigation systems is explored using a bioeconomic simulation model of lettuce production on the Gnangara Mound near Perth, Western Australia. Sandy soils with poor water and nutrient holding capacity are associated with declining marginal productivity of water at high water use, which would create an incentive to reduce water use and to adopt closer sprinkler spacing if farmers had correct information about the declining marginal productivity of water. Incorrect perceptions regarding water–yield relationships lead to over use of water by up to 50 per cent and reduce profits by 475 per crop hectare (12 per cent) in the short run, and remove the incentive to adopt more efficient systems in the long run. Higher water prices create an incentive to reduce irrigation scheduling time in the short term and to adopt more uniform sprinkler systems, and tend to reduce the discrepancies associated with poor information about the marginal productivity of water. The low level of adoption of efficient irrigation systems in the region might be explained partly by historically poor water governance and insufficient extension regarding water productivity and technology.  相似文献   

9.
Large‐scale tree plantations in high rainfall upstream areas can reduce fresh water inflows to river systems, thereby imposing external costs on downstream irrigation, stock and domestic water users and wetland interests. We take the novel approach of expressing all benefits and costs of establishing plantations in terms of $ per gigalitre (GL) of water removed annually from river flows, setting upstream demands on the same basis as downstream demands. For the Macquarie Valley, a New South Wales sub‐catchment of Australia’s Murray‐Darling Basin, we project changes in land and water use and changes in economic surpluses under two policy settings: without and with a policy requiring permanent water entitlements to be purchased from downstream parties, before plantation establishment. Without the policy, and given a high stumpage value for trees ($70/m3), upstream gains in economic surplus projected from expanding plantations are $639 million; balanced against $233 million in economic losses by downstream irrigators and stock and domestic water users for a net gain of $406 million, but 345 GL lower mean annual environmental flows. With the policy, smaller gains in upstream economic surplus from trees ($192 million), added to net downstream gains ($138 million) from sale of water, result in gains of $330 million with no reduction in environmental flows. Sustaining the 345 GL flow for a $76 million (406–330) reduction in gains to economic surplus may be seen to cost only $0.22 million/GL; but this is much lower than the market value of the first units of that water to agriculture and forestry.  相似文献   

10.
Strategies to reduce phosphorus and sediment yields are identified for two Australian catchments using a nonlinear optimisation model. This provides novel insight into the cost‐effective management of dual pollutants of water courses in Australia. A strong degree of complementarity between the two pollutants is highlighted, given the adsorption of phosphorus to sediment that augments the value of gully and streambank management for mitigation. However, the relationship between the two pollutants is asymmetric. A 30 per cent reduction in phosphorus yield achieves a 75 per cent reduction in sediment yield in one catchment, while a 30 per cent reduction in sediment yield achieves only a 12 per cent reduction in phosphorus yield. Sediment abatement costs are low given the efficiency of gully and streambank management. A 30 per cent phosphorus reduction lowers profit by 3–7 per cent, while a 30 per cent sediment reduction lowers profit by around 1 per cent. Land‐use optimisation requires spatial heterogeneity in land‐use and gully/streambank management responses. Overall, this research demonstrates the need to determine whether one pollutant is more important than another, while recognising the potential that mitigation practices possess for the reduction of multiple emissions during their evaluation.  相似文献   

11.
We analyse food demand patterns of Indonesian households from a resource intensity perspective and quantify the impact of changed demand patterns on the use of three major resource inputs: fossil fuel; land; and water in agricultural production. Using Indonesian Family Life Survey data, 13 major food items (which constitute 70 per cent of food expenditure) are categorised into low, moderate and high resource intensity, and income elasticity and Engel curves are estimated for the period from 1997 to 2007. Our results show that income growth in Indonesia is associated with demand patterns that are more resource intensive. By 2007, per capita requirements of fossil fuel, land and water increased by 42.7 per cent (3.13 MJ), 44.9 per cent (1.24 m2) and 50.4 per cent (2.1 kL), respectively, relative to 1997. The results imply that, at least for Indonesia, changed food demand patterns resulting from economic development will increase the demand for natural resources substantially.  相似文献   

12.
The water reforms undertaken in the Murray–Darling Basin, Australia since 2007 have been viewed as a model for other countries seeking to respond to water insecurity. Here, a policy review is provided of this water reform and whether it delivers on key environmental objectives in the 2007 Water Act (the Act). The evaluation includes a review of the 2012 Basin Plan, a key instrument of the Act, and complementary policies associated with the acquisition of water entitlements for the environment via direct (reverse tenders) and indirect (infrastructure subsidies) means. Using the objects of the Act as a benchmark, an evaluation is provided of the following: (i) planned reductions in irrigation water extractions in the 2012 Basin Plan; (ii) risks associated with the 2018 amendments to the Basin Plan that, collectively, allow for an increase in irrigation water extractions of some 22 per cent, relative to the sustainable diversion limits specified in the 2012 Basin Plan; (iii) Basin‐scale environmental outcomes achieved, as of the end of 2018; and (iv) economic effects of direct and indirect methods of acquiring water for the environment. Findings from the review generate the “Do's” and “Do Nots” of water reform for Australia, and possibly other countries, when managing the trade‐offs between water for irrigation and the environment.  相似文献   

13.
Agriculture is the largest type of land use in the UK, accounting for about 77 per cent of the total area, compared with an average 50 per cent for the EU27. But in common with most high-income countries, agriculture's contribution to UK GDP and employment is low, at about 0.5 and 1.8 per cent, respectively, although the regional importance of the sector (and its associated food and farming industries) varies considerably.Of the 17.5 million ha used for agriculture, about 28 per cent is allocated to crops, and 67 per cent is grassland. The grassland includes 4.4 million ha of sole-owned rough grazing and 1.1 million ha of common land in mainly upland “disadvantaged areas,” primarily used for beef and sheep production. This has a major influence on land use, especially in the northern and western parts of the UK.From the 1930s until the mid-1980s, UK policy promoted increases in agricultural productivity to feed the nation from its own resources. An array of income and production support measures encouraged intensive farming, including a relative switch to arable farming in eastern areas. Since the early-1990s, policies have sought simultaneously to make UK agriculture internationally competitive and environmentally benign. These policies, evident in the Agenda 2000 Reforms of the Common Agricultural Policy, point the way forward for the future. It is likely that a greater distinction will emerge between policies to protect natural resources and enhance the flow of non-market ecosystem services from rural land, and agriculture and food policies intended to encourage an appropriate proportion of national food requirements to be met from domestic sources.It seems likely that over the next 50 years, the UK's land area will be required to deliver an increasingly diverse range of private and public goods to meet growing human needs and aspirations. This will require a balance of policy-driven goals and market forces. It will also need a much improved understanding of the trade-offs between food production and environmental goals and of the institutional arrangements required to achieve a balance of economic, social and environmental outcomes.  相似文献   

14.
A mixed-integer non-linear programming model that minimises the total regulatory costs of controlling nitrogen oxide is used to investigate how a newly proposed permit trading scheme in Taiwan, which incorporates the features of banking and a non-one-to-one trading ratio, may affect firms’ emission reduction strategies and permit trading decisions. Compared to the previous regulation where only an air pollution fee is used, the new regulation that requires a reduction in emissions by 10 per cent from the emission level in the year 2000 for a 5 year period will increase the costs by 77 per cent, which is equivalent to US$9.87 million. The design of banking and the increasing returns to scale characteristic of pollution control among firms might lead to an uneven reduction in emissions in each year. Setting a lower reservation rate for banking would, however, help maintain a more stable environmental quality without a significant loss to the government in terms of air pollution fee revenue.  相似文献   

15.
When entitlements to access water in fully allocated river and aquifers are specified in a manner that is inconsistent with the ways that water arrives, flows across and flows through land, inefficient investment and water use is the result. Using Australia's Murray Darling Basin as an example, this paper attempts to reveal the adverse economic and water management consequences of entitlement and water sharing regime misspecification in regimes that allow water trading. Markets trade water products as specified. When entitlements and the water sharing system are not designed in a way that has hydrological integrity, the market trades the water management regime into trouble. Options for specification of entitlement and allocation regimes in ways that have hydrological integrity are presented. It is reasoned, that if entitlement and allocation regime are set up in ways that have hydrological integrity, the result should be a regime that can autonomously adjust to climatic shifts, changes in prices and changes in technology without compromising environmental objectives.  相似文献   

16.
The cost of flooding on farm land depends on land use, on the frequency, seasonality, duration and depth of flooding, and on water quality. This paper describes a method to calculate the average annual cost of flooding and the extra benefits or costs associated with given changes in flooding regime, illustrated by means of a simplified case study which examines the agricultural benefits of reduced summer flooding on grass in an area of environmental importance. Using hydrological and agro-economic data, the method derives the cost of individual flood events occurring in any one month for a given land use, weights these according to observed seasonality of flood flows, and derives average annual costs per hectare and for the floodplain as a whole for given levels of flood risk. The method is useful for appraising river flood alleviation schemes whereby the effects of changes in flood risk, flood seasonality or land use can be assessed.  相似文献   

17.
Long-term land leasing offers a viable alternative to land ownership in relation to increasing efficiency of agricultural production, economies of scale, and delivering environmental improvements in terms of land management. However, with no significant tenanted sector in Northern Ireland, access to land via long-term land leasing is limited. This study analysed the barriers and enablers of long-term land leasing. To achieve our objective, we employed a mixed methods approach. The results show that the main barriers to long-term land leasing were environmental concern (around how the land will be managed), inheritance tax implications and the potential effect of long-term land leasing on future succession plans of the farm business. We also found that as much as 70 per cent of the farmers surveyed believe the inclusion of a ‘break clause’ and the introduction of income tax incentives will encourage the adoption of long-term land leasing, while 61 per cent of the farmers stated that the environmental management of the land will encourage long-term land leasing. The study concluded that any model designed to encourage long-term land leasing in Northern Ireland should include clauses which cover the environmental management of the land and break clauses. Income tax incentives for landowners could also be considered.  相似文献   

18.
Policy instruments designed to increase environmental flows in the Murray–Darling Basin are compared using TERM‐H2O, a detailed, dynamic regional CGE model. Voluntary and fully compensated buybacks are much less costly than infrastructure upgrades as a means of obtaining a target volume of environmental water, even during drought, when highly secure water created by infrastructure upgrades is more valuable. As an instrument of regional economic management, infrastructure upgrades are inferior to public spending on health, education and other services in the Basin. For each job created from upgrades, the money spent on services could create between three and four jobs in the Basin.  相似文献   

19.
Commonly used pesticides and handling practices which might expose farmers and their environment to chemical hazards were investigated in the Irepodun/Ifelodun local government area of Ekiti State, Nigeria. Direct field observations and answers to a structured questionnaire from a random sample of 150 farming households showed that commonly used pesticides comprised herbicides (48.3 per cent), fungicides (28.2 per cent) and insecticides (23.5 per cent). Of these, 86.7 per cent are classified as ‘highly’ hazardous by the World Health Organization (WHO) and have been banned or restricted in many developed countries. Nearly all of the farmers (94.7 per cent) had received no formal training in safe pesticide use and mixed different products. Farmers suffered from discomforts ranging from eye irritation (91.3 per cent), skin problems (87.3 per cent), nausea (86.0 per cent), headache (83.3 per cent) and vomiting (58.0 per cent). More than half of the pesticide applicators (61.3 per cent) sprayed pesticides near water bodies. Only a few farmers reported decreasing trends in numbers of beneficial insects (27.3 per cent) and other animals (29.3 per cent). The results showed that the awareness of farmers and authorities needs to be raised regarding the use of protective equipment and correct procedures when handling pesticides and, also, that there should be stricter enforcement of existing pesticide regulation and monitoring policies to minimize the threats that the farmers' current practices pose to their health and to the environment.  相似文献   

20.
Downside risk, which refers to deviations below a threshold, is often important in water management decisions, especially in areas with large and skewed variations in precipitation patterns. In this paper, we present a model for a reservoir manager who is downside risk averse and who performs a dynamic allocation of irrigation water, taking into account the negative effects of droughts on farm profits and different environmental constraints. We analyse the water stock, flows and agricultural profits for alternative environmental restrictions and thresholds for irrigation levels and find that stricter environmental constraints increase total water supply and carryover stock, while higher penalty thresholds lead to their overall decrease. Furthermore, increasing penalty thresholds leads to a higher emphasis on avoiding shortages, at the expense of lower average profits.  相似文献   

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