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1.
Allocation of fish resources is a controversial subject. This is partly because of our limited understanding of the values of fishing opportunities. This study investigates fishing site choices in Western Australia using national survey data covering eight major fishing regions and forty‐eight fishing sites. We estimate a random utility model (RUM) of site choice with a supporting negative binomial model of angler‐specific expected catch rates. Value estimates for fish types, fishing site attribute changes and access values are presented and discussed.  相似文献   

2.
This is a study on demand for outdoor recreation in a national system of environmentally protected areas. The exercise is based on a nationwide survey carried out in 1996 from a stratified random sample of 5,574 Italian households. Data on socio‐economic characteristics and recreational choice behaviour of respondents were collected and this information was supplemented by a second data‐base containing information on 193 Italian EPAs in order to characterise the different outdoor destinations on the basis of their recreational attributes. These data sets are used here to model choices of outdoor recreation within environmentally protected areas, using a sequence of three different models: (i) a dichotomous choice logit model for the probability of participation conditional on household covariates; (ii) a count data Poisson model to estimate the household's expected number of trips per year; (iii) a conditional logit model to estimate the probability of site selection conditional on site attributes. We report the estimated per‐trip welfare changes derivable from an actual policy proposal which would extend the area under environmental protection by ten per cent.  相似文献   

3.
Although the regulations are imperfectly enforced, logging firms in the Brazilian Amazon are subject to forest management regulations intended to reduce environmental damage and protect future forest productivity. Additionally, voluntary best practices firms adopt to achieve environmental performance that exceed regulatory requirements are largely limited to reduced impact logging (RIL) systems that reduce harvest damage relative to conventional logging systems used by a large majority of firms in the region. Existing regulations combined with best practices may not be adequate to ensure sustained yields. This inadequacy is an important issue as Brazil implements an ambitious program of forest concessions on public lands. We analyze the profitability and environmental outcomes of best logging practices and proposed sustainability requirements. We propose two operational definitions of sustainability (the first focusing on sustaining stand-level timber volumes and the other focusing on sustaining species-level volumes within the stand) based on sustaining timber inventories across cutting cycles rather than on sustaining overall harvest yields. RIL is shown to be profitable for loggers and increase the timber available for future harvests. While volume predicted to be available for the second and third harvests are significantly lower than the available timber in the unlogged forest, the second and third harvests are projected to be profitable and have the potential for sustainability despite high opportunity costs. However, as harvesting is repeated into the future, results show the composition of the harvest shifts from higher-value shade-tolerant and emergent species toward a greater reliance on longer-lived, lower-value pioneer species. This shift may create pressure to expand the forest base under management in order to continue to supply high-value species or increase the risk of timber trespass in conservation units and areas under community or indigenous management.  相似文献   

4.
The main purpose of this study is to measure environmental effects and recreational benefits under different hypothetical scenarios program, involving quality improvement in Tien‐Wei Highway Garden, which is the biggest cultivated flower land in Taiwan. The contingent behavior model was adopted. The data combined actual number of trips under current quality of environment combined and the intended number of trips for expected scenarios of environmental quality improvement and congestion mitigation. For the empirical model, on‐site Poisson model was performed to correct truncated and endogenous stratification issues from on‐site surveys. The results show that the estimated average consumer surplus is greater in contingent behavior method than the one in the traditional travel cost model. Also, the estimated recreational benefits in contingent behavior method are more precise than those in the traditional travel cost method. The environment benefits to consumers are communicated with the programs that changes in environment quality. Meanwhile, the incremental economic benefits comprise the gain associated with the improvement of environmental quality.  相似文献   

5.
Japan's fishery harvest peaked in the late 1980s. To limit the race for fish, each fisherman could be provided with specific catch limits in the form of individual transferable quotas (ITQs). The market for ITQs would also help remove the most inefficient fishers. In this article we estimate the potential cost reduction associated with catch limits, and find that about 300 billion yen or about 3 billion dollars could be saved through the allocation and trading of individual‐specific catch shares.  相似文献   

6.
This article focuses on how the linkages between various farm‐level decisions affect the choice of measures to reduce nitrogen leaching from crop production. A mathematical programming model is developed. The model considers not only management decisions that affect nitrogen leaching directly, but also other decision variables such as scheduling of field operations and machinery investments. A simplified analysis that ignores the latter management decisions, and the linkages between the various decisions, may result in abatement policies that are not cost‐effective because the policies will have other effects than expected. As an example, the empirical results show that subsidies to catch crops and spring ploughing may contribute to increased nitrogen load, quite contrary to the purpose of these subsidies. Further, it is noted that the characteristics of the production system make it costly to change land use, tillage practices, or fertilizer use drastically. Instead, cost‐effective nitrogen abatement includes a mix of various adjustments of farm‐level production practices. The EU set‐aside payment appears to reduce abatement costs.  相似文献   

7.
"This paper uses a multinomial discrete choice model and data from the Philippines to examine migrant choice between alternative destinations. Travel costs and perceived opportunities at the upland frontier are more important than general (upland plus lowland) destination attributes that indicate more developed social infrastructure or greater expected welfare. For example, migration streams are larger to destinations where the public share of forestland and the road system are larger. These features also characterize regions of more rapid deforestation. Therefore, emigration policies must recognize their effects on deforestation at the frontier--and their anticipated indirect effects on downstream environments."  相似文献   

8.
Deadwood is recognized as one of the most important resources affecting forest biodiversity. Its absence from the forest landscape is, therefore, of concern, such that one official Swedish environmental objective is to increase the volume of deadwood. However, increasing the use of renewable energy sources, another environmental goal, is likely to work against this biodiversity objective. In this study we utilize a regional economic forest sector model, focusing on northern Sweden, in order to estimate the effect of a large scale introduction of stump harvest on the future use of forest fuel. In addition, an ecological model, describing the relationship between the availability of stumps and the abundance of saproxylic beetles, is linked to the economic model.The parameters used in the economic model are derived from a data set spanning 28 years while the ecological model is derived from a survey of ten clear cuts, undertaken seven years after the clear cutting, in order to investigate the abundance of saproxylic beetles in stumps. We simulate the effects of an increased demand for wood fuels in northern Sweden, with or without stump harvest. The two scenarios have different effects on all major round wood markets in the region, as well as on the abundance of saproxylic beetles. More specifically, the harvest of stumps is associated with a 5% reduction in the mean abundance of saproxylic beetles living in deadwood on future clear cuts and a 3% increase in the use of renewable energy recourses in heating plants.  相似文献   

9.
Annual recruitment of the New Zealand longfin eel (Anguilla dieffenbachii) has decreased by 75 per cent since significant levels of commercial fishing began in the early 1970s. This motivates application of a multiple‐cohort bioeconomic model to a New Zealand longfin eel fishery to investigate its optimal management and ascertain the suitability of existing regulatory policy. The use of historical harvest to calculate total allowable catch is asserted to be unsustainable based on recovery dynamics. In addition, individual transferable quota systems are argued to be fundamentally flawed for the protection of longfin fisheries because of high‐grading, low‐surplus production and a current lack of effective stock‐assessment procedures. Area closure and the spatial definition of harvest rights are attractive alternatives given the territoriality of longfins and high larval spillover. The importance of unfished reserves is reinforced when significant uncertainties regarding population strength, harvest intensity and growth dynamics are considered. Restriction of exploitation to older cohorts in fished areas is demonstrated to maximise economic yield.  相似文献   

10.
The Economic Value of Lottery-rationed Recreational Hunting   总被引:2,自引:0,他引:2  
Lottery-rationed permit systems are used to allocate hunting opportunities where demand for permits exceeds the ability of the animal populations to sustain hunting harvest levels. Attempts to estimate the values of lottery-rationed hunting use a zonal travel cost model where applications per capita formed the dependent variable and expected travel costs represent the price variable. This paper reexamines this analysis using a discrete choice travel cost model which incorporates the expectation of receiving a permit. This model is developed for lottery-rationed antelope hunting in Alberta. Choice in the lottery-rationed hunting context involves selecting one site from a set defined through management regulations. The discrete choice travel cost model is proposed as superior to the early models because it better represents this behavioral process. Les systèmes de permis tirés par loterie sont utilisés pour l'attribution des possibilités de chasse dans des situations où la demande dépasse la capacité des populations de gibier à soutenir les niveaux annuels de prélèvement. Les tentatives antérieures pour estimer les valeurs des permis de chasse tirés par loterie utilisaient généralement un modèle de coût de déplacement par zone, dans lequel le nombre de demandes par habitant était la variable dépendante et les coûts de déplacement attendus représentaient la variable prix. Dans la présente étude, l'auteur a repris cette analyse en utilisant un modèle de coût de déplacement à choix discret, qui tient compte de l'espérance du chasseur de recevoir un permis. Le modèle est appliquéà la chasse à l'antilope d'Amérique en Alberta. Dans le contexte des permis de chasse tirés par loterie, le choix consiste à miser sur un des territoires énumérés sur une liste établie par les services de réglementation de la chasse. L'avantage du modèle de coût de déplacement avec choix discret sur les modèles antérieurs est qu'il tient mieux compte de ce processus de comportement.  相似文献   

11.
Farmers in low‐income rural economies often fail to switch to cash crops from staple production despite the positive income effects of commercialization expected by policy makers. The literature suggests that market failures prevent households from cash crop adoption but remains inconclusive regarding farmers' motives and the effects of commercialization. This article contributes to the debate by offering an original approach to the analysis of commercialization outcomes and farmers' decisions. It consists of applying a model with essential heterogeneity and a semiparametric estimation technique to analyzing harvest value returns to cash cropping. Using Malawian data, we show considerable heterogeneity in harvest value returns to cash cropping both within and between groups of farmers choosing different crop portfolios. Importantly, the results imply rational choices based on comparative advantage considerations of farming households: farmers self‐select into the activity where they expect higher gains and adopt cash crops when facing weaker market barriers.  相似文献   

12.
Substantial public scrutiny about adverse environmental impacts of the dairy sector has resulted in increased environmental regulations. A behavioral model of location and production is developed to examine the impacts of environmental regulations, traditional location factors, and agglomeration economies on the spatial structure and geographical location of dairy production. The results show that counties in the states with more stringent environmental regulations tend to lose dairy inventories to those with less stringent policies. There are substantially meaningful spatial patterns of dairy production. Current dairy production levels are positively correlated while changes in production levels are negatively correlated across counties.  相似文献   

13.
Statements of willingness to pay (WTP) have been shown to be dependent upon the framing of the hypothetical market. In this paper we investigate the effects of variations in the timing and location of choice experiment questions concerned with conservation of a UK national park, as research involving measurement of psychological well‐being suggests potential differences for the same individual dependent upon when and where preferences are elicited. We apply the choice experiment technique to the valuation of changes in upland agricultural and semi‐natural landscapes in the Peak District National Park in the UK, to investigate whether timing and location of elicitation (context) affects the value associated with changes in ecosystem services under different management regimes. Four treatments are employed – using the same sample of individuals answering the same choice scenarios – to measure WTP ex‐ante (off site), in situ (on site), and ex‐post at two different time intervals (off site). We show that our on‐site (in situ) treatment generates very different estimates of preferences than any of the off‐site treatments. That stated preferences associated with environmental goods are so context dependent may have implications for the use of stated preferences in policy analysis in terms of identifying how environmental policy is funded and the divergence in value attributed to sampling different populations.  相似文献   

14.
The travel cost model is the standard model used in the recreation demand area. This model assumes that the decision on the number of trips in a given time period (a season, for example) to a particular site is determined at the beginning of the time period. For certain types of recreation activity, it may be better to model the decision to take a trip to a given site as a function of the outcome of previous trips and the realization of random variables on previous trips (as well as travel and time costs). The spatial choice behavior itself may be sequential in nature rather than continuous. In this paper, a model is developed which specifies the choice of a discrete number of sequentially chosen trips to a given site as a function of site-specific variables and values realized on previous trips. This model improves upon the existing travel cost model by specifying discrete integer values for the number of trips, developing an explicit relationship between trips taken and the number of days spent on each trip, and allowing intra-seasonal effects to determine the probability of taking an additional trip. A comparison is made between the traditional travel cost model estimates of consumer's surplus and the estimates from this sequential discrete choice model.  相似文献   

15.
This article implements an econometric approach for generating primal capacity output and utilization measures for fisheries. In situations where regulatory, environmental, and resource conditions affect catch levels but are not independently identified in the data, frontier-based capacity models may interpret such impacts as production inefficiency. However, if such inefficiencies are unlikely to be eliminated, the implied potential output increases may be unrealistic. We develop a multi-output, multi-input stochastic transformation function framework that permits various assumptions about how output composition may change when operating at full capacity. We apply our model to catcher-processor vessels in the Alaskan pollock fishery.  相似文献   

16.
This article examines two issues concerning the trip–taking behavior of recreational anglers over the course of a season. The first is whether the random component of trip utility is serially correlated across trip occasions. The second is the heterogeneity of preferences among anglers. Recent research has examined heterogeneity among recreational trip–takers using random parameters models. In this article, the population of anglers is, instead, cast as a collection of several subpopulations distinguished by angler preferences, and the method of finite mixtures is used to identify these subpopulations.  相似文献   

17.
An understanding of the link between the level of inputs and resultant level of outputs is of considerable importance when trying to manage fisheries through input controls. To this end, studies of several fisheries have been undertaken to examine this relationship through the estimation of production functions and frontiers, using either catch weight or revenue as the dependent variable. The choice of the appropriate output variable to use in the analysis will depend on the objectives of the fishermen. Maximisation of catch weight is often proposed as an objective of fishermen rather than maximisation of profits. In this paper, the technical efficiency scores of vessels operating in the Spanish south‐Atlantic trawl fishery are estimated using the stochastic production frontier approach. The production frontiers are estimated with both the weight and the value of the catch as the dependent variable. The results of the analysis suggest that fishermen adopt a range of strategies but relatively few aim to maximise catch weight only. The differences in strategies may reflect heterogeneous attitudes towards risk, with more risk averse fishermen aiming to trade‐off some potential catch value for a more certain quantity of catch.  相似文献   

18.
The economic efficiencies of the Danish, Icelandic, and Norwegian cod fisheries are examined. For this purpose, nonlinear aggregate models of these fisheries are constructed. Comparing the calculated optimal harvest and biomass quantities with the actual fisheries provides a measure of the degree of efficiency in these fisheries. The comparisons confirm that the cod harvesting policies of these countries have been hugely inefficient in the past. It appears that inefficiency has been increasing over the last three to four decades, even after TAC regulations replaced open access, indicating that the management policies adopted by all three countries have failed to cure overfishing.  相似文献   

19.
This paper explores how changes in Australia’s grain industry supply chains are likely to impact on the nature and profitability of an Australian farmer’s grain harvest logistics. A simulation model is used to show how receival site rationalisation, cheaper on‐farm storage, larger trucks, higher‐yielding crops and new harvest technologies, separately and in combination, affect the nature and profitability of a farmer’s grain harvest logistics. Applying the model to a typical Australian grain farm shows that many of these changes unambiguously advantage the farm business, and often, the combination of these changes increases a farmer’s harvest profits by at least 10 per cent. For many farmers, the task of efficiently designing and managing harvest logistics will be an increasingly difficult yet important series of choices due to the range of storage options, grain pathways, crop portfolios and market opportunities that are arising. A farmer’s decisions about cost‐effective on‐farm storage and transport, and their judicious use, will be a key contributor to additional profit in future years.  相似文献   

20.
This article measures the impact of modern technology adoption in raising farmers' environmental awareness and the impact of farmers' environmental awareness on resource use by utilizing survey data from 21 villages in three agro‐ecological regions of Bangladesh. The econometric analysis is based on the application of the Tobit model explaining farmers' environmental awareness in the first stage and a profit function examining environmental awareness and resource use relationships in the second stage. Results reveal that the “level” and “duration” of involvement with modern technology raises farmers' environmental awareness, and that farmers' environmental awareness reduces resource use including chemicals. Farmers, who are aware of the adverse environmental impacts of modern agricultural technology, use lower amounts of all inputs in order to avoid further environmental damage. Therefore, efforts to raise farmers' environmental awareness are expected to enhance intangible benefits accruing from a relatively less chemical‐intensive environment.  相似文献   

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