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1.
Recent decades have seen a rapid increase in the area of privately owned forest plantations in Ireland. This has been largely driven by grant aid and annual premium payments from the government and the European Union. These forests are significant carbon sinks and as such are delivering added benefit to the country by contributing to greenhouse gas reductions under the Kyoto Protocol.The direct impact of government subvention on the net present value (NPV) for a defined forestry plantation is investigated. The added value of carbon sequestration to forestry investment is also examined using the Forestry Commission (Great Britain) carbon model. Extending the typical assumption of a constant carbon price for project appraisal purposes, this paper allows carbon prices to evolve randomly according to a flexible stochastic price process. The model chosen is an extended mean-reverting jump-diffusion with the flexibility to capture the higher order statistical features (i.e. skewness and kurtosis) of the carbon markets. This allows for an analysis of the risk and uncertainty around the NPV from exposure to stochastic carbon prices. It is shown that government grants and annual premiums for afforestation significantly improve the NPV on forestry investment. Carbon sequestration is shown to add further value.  相似文献   

2.
This paper presents a new forest harvest scheduling model taking into account four conflicting objectives. The economic factor of timber production is considered and also aspects related to environmental protection. We also incorporate adjacency constraints to limit the maximum contiguous area where clear-cutting can be applied. The model proposed is applied to a timber production plantation in Cuba located in the region of Pinar del Río. One factor to be taken into account in Cuban plantations is that the forest has a highly unbalanced age distribution. Therefore, in addition to the classical objectives of forest planning, we have the objective of rebalancing age distribution by the end of the planning horizon. Explicitly, the four objectives considered in the model are: (a) obtaining a balance-aged forest; (b) minimizing the area with trees older than the rotation age; (c) maximizing the NPV of the forest over the planning horizon; and (d) maximizing total carbon sequestration over the whole planning horizon. The solution to the proposed model provides a set of efficient management plans that are of assistance in analysing the tradeoffs between the economic and ecological objectives. The model is also applied to randomly generated simulated forests to compare its performance in other contexts. As the problem is a multiobjective binary nonlinear model, a metaheuristic procedure is used in order to solve it.  相似文献   

3.
In this paper, a spatial-based economic model is proposed with the aim of estimating the most likely harvest cost of a forest block in relation to its particular morphological and operating features. This work, which is based on the classical stumpage price assessment method, presents an economic balance of a forest cut, attained by conducting a cost analysis of each logging phase of the different standard harvesting strategies. The study area is in the North-West of Italy, in the Mount Cotolivier forest compartment, in Oulx, Piedmont. The map of the stand structure, which is included in the Oulx Forest Management Plan, was used to locate blocks (areas considered homogeneous according to the stand structure and forest typology) where silvicultural cuts could be scheduled. The feasibility of the selected logging strategies was mapped considering six conditioning factors, of both a topological and a topographic nature. Their influence was weighted by means of a score assignation and integrated in a Multi-Criteria Decision Making procedure. The scores were mathematically combined to calculate a spatial dependent cost-function (Block Exploitation Aptitude, BEA) in which the suitability of each block to be harvested was mapped through a specific strategy. The obtained BEA was then used to estimate the most suitable productivity rate of the harvests of each block. The unitary costs of the strategies were estimated and then compared to find the most profitable one for each block.This model has proved to be effective in generating objective economic results concerning harvest cuts in productive stands in mountainous areas. The proposed methodology simultaneously takes into account different factors and generates feasibility scenarios, in the space domain, for the considered harvesting strategies. The proposed model represents a prototype on which an operational Decision Support System could be based to assist forest managers over the short-medium term.  相似文献   

4.
不同经营主体和立地条件的马尾松经营经济效益评价   总被引:1,自引:0,他引:1  
王小玲  沈月琴  王枫  刘强 《林业经济问题》2012,32(5):412-417,421
以马尾松为例,采用NPV、IRR、LEV三个指标,并运用现金流量表分析马尾松经营周期内资金的变化情况,分别对比了不同经营主体、不同立地条件投入产出的差异及其构成。结果表明:(1)农户和林场马尾松经营的NPV、LEV差异明显,但IRR差异并不大,而不同立地条件三者均存在明显差异;(2)农户和林场现金流出、流入、净现金流量差异明显,林场明显高于农户,且用工成本构成了现金流出的主要部分;(3)立地条件好的地块现金流出量、流入量、净现金流量要明显高于立地条件中等和差的地块。并针对以上结论,提出增加马尾松营林面积和森林蓄积的政策建议。  相似文献   

5.
Carbon sequestered through increased forest biomass provides a low cost means to curb emissions and has become a major focus of New Zealand's Emissions Trading Scheme. We present a forest planning optimisation model where land use is governed by forest owners maximising the returns to both timber harvest and carbon sequestration. By varying carbon prices, we model efficient trade‐offs between the two forest activities along a modified production possibility frontier for four distinct wood supply regions in New Zealand. Results show that while more productive regions such as the Central North Island (CNI) and Northland have a greater capacity as a carbon sink, it is the less productive regions that have a comparative advantage in carbon sequestration in terms of a lower cost of wood production revenue foregone. However, moderate increases in carbon uptake can be achieved in the CNI at low opportunity cost by subtle changes in forestry management. The implication for policy‐makers is that initial increases in carbon sequestration will be achieved at the lowest cost to society by favouring high volume timber production in some productive woodland areas and/or by more carbon farming in less productive areas.  相似文献   

6.
评价林业投资的实物期权方法   总被引:1,自引:1,他引:1  
评价风险较高的林业投资,传统的净现值法(NPV)容易低估项目的价值,不能客观地对林业投资做出正确评价。林业项目的不确定性反映了林业投资具有一定的期权特性,因此本文基于实物期权的理论和方法,建立了林木采伐的实物期权决策模型,将林木收益问题当作一个实物期权问题处理,应用实物期权模型来决定林木最佳采伐时机。  相似文献   

7.
Managing Mississippi's forest lands to produce both quality wildlife habitat as well as merchantable timber can be a daunting challenge for forest managers and a source of great concern for the public. In some cases, producing both the quantity and quality of habitat needed and the timber desired is all but impossible. In other cases, a delicate balance that achieves both objectives can be struck. The objective of this study was to quantitatively estimate monetary gains and losses and changes in timber inventories relative to the timber growing stock when producing more or less habitat for the red-cockaded woodpecker (RCW) (Picoides borealis). USDA Forest Service vegetation data, habitat ratings, and economic variables were compiled for those regions of Mississippi best suited for RCWs. Data was then analyzed with Spectrum, the USDA Forest Service-based forest planning software. Models maximizing such objectives as net present value (NPV) alone as well as five different levels of RCW habitat quality over a 50-year rotation were developed. Revenue foregone, acres and volumes harvested, land expectation value (LEV), and equivalent annual income (EAI) were compared for all objectives for the South Central Hills and Pine Belt regions of Mississippi (1,036,208 acres) for three ownership types. As expected, when maximizing for any quality level of RCW habitat, revenue forgone was higher ($0.11–$49/acre/year) than for NPV alone. Volume harvested for high-quality habitat ranged from 152,296 to 10,237,649 cunits, while harvests from low-quality habitat ranged from 637,491 to 116,357,673 cunits. Lower levels of habitat management allowed for an increased emphasis on timber harvesting. In general, we determined that increases in habitat quality resulted in lower timber harvest levels and increased revenue forgone than regimes maximizing NPVs. While this result may be expected, of greater importance are the relative differences between regimes and the ability to use these values for policy decisions.  相似文献   

8.
The assessment of alternative forest management strategies should account not only for the private benefits to forest landowners but also for the ecological, environmental and economic benefits valued by society. There are a number of empirical valuation methods that may contribute to that assessment. These methods involve several steps: data acquisition, model specification and estimation. In this paper, this approach is illustrated in the context of a survey regarding alternative management strategies for a forest area in Central Portugal by implementing a contingent valuation experiment where an advanced landscape visualisation technique is employed to generate the visual information conveyed in the valuation scenarios. Several econometric model specifications are considered as well as alternative approaches to handle zero willingness to pay values and protest responses. The results obtained suggest the potential of the proposed approach for an effective comparison of alternative forest management strategies.  相似文献   

9.
Fisheries management is characterised by multiple objectives, some of which may be complementary, while others may require trade‐offs between outcomes. Balancing these objectives is made more complex in the case of multispecies and multigear fisheries. In this paper, we develop a bioeconomic model that captures the key elements of such a fishery to test a range of potential harvest strategies to provide insights into how economic target reference points could lead to both desirable and undesirable management outcomes (e.g. discards). The model is developed as a long‐run optimisation model to identify target reference points to achieve multispecies maximum economic yield, and a dynamic recursive optimisation model, which includes more realistic representation of fishers’ behaviour, such as discards and trading of under‐caught species quotas. The potential economic, social and ecological impacts are evaluated using data envelopment analysis (DEA). The results suggest that the use of proxy target reference points can result in short‐term economic benefits at the cost of slower stock recovery and higher discarding. Limiting the number of species subject to quota controls may also prove beneficial in multispecies fisheries, while ensuring quota markets are efficient is likely to produce benefits irrespective of the harvest strategy adopted.  相似文献   

10.
One-third of the forestland in the U.S. is owned by 10.4 million family forest owners. Their collective decisions have a great impact on the sustainability of forest landscape across the country. Public policies and programs for encouraging landowners to properly manage their land include cost-share, forest certification, and conservation easements. However, to date, less than 6% of the family forest owners have participated in a cost-share program, less than 1% have certified their land, and less than 2% have an easement. By analyzing data from USDA Forest Service's National Woodland Owner Survey, we examined the characteristics of family forest owners who had participated in these programs and identified strategies to capitalize on these landowner characteristics to improve current programs and attract a wider range of participants. We found that family forest owners with larger land holdings were more likely to participate in all three types of programs. Obtaining forest management information or advice was important for program participation; however, the effects differed depending on the types of programs and the sources of information. Income was not significant in predicting participation in cost-share programs, implying family forest owners from lower-income strata were not more likely to use cost-share program. The results also suggest the importance of targeting the right audience when promoting forest certification programs, namely those who are participants of cost-share programs, own forestland for reasons other than farming or ranching, and plan to harvest sawlogs or pulpwood in the future. Age was not significant in any of the empirical models. This result is particularly intriguing in the context of conservation easement, considering recent discussions about the high cost of dying unprepared and the potential for promoting conservation easement as part of estate planning among older family forest owners. Finally, few variables were significant in the model predicting landowner decision about donating or selling an easement, suggesting the easement decision is very different from cost-share and forest certification decisions and further efforts are needed to understand the dynamics of this increasingly popular conservation policy tool. In summary, this study provides a better understanding of the relationship between program participation and the demographics, attitudes and behaviors of family forest owners. This understanding contributes to the development of outreach strategies for improving landowner interest in forest conservation programs.  相似文献   

11.
Abstract

The objectives of this study were to identify the optimal extrinsic and intrinsic attributes for a range of chilled nutrientenriched orange juice beverages; and to evaluate the contribution of advanced concept optimisation research techniques to new product design and the strategic marketing of innovative functional beverages. A conjointbased survey was administered in both Dublin and Cork between May and September 2004. The results suggested that firms should not rely solely on functionality to leverage a competitive advantage when developing functional beverages. Advanced concept optimisation research techniques contribute towards effective knowledge management in the new product development (NPD) process.  相似文献   

12.
我国林权抵押贷款研究综述   总被引:1,自引:0,他引:1  
通过对2003年以后我国的林权抵押贷款相关文献的梳理归整,重点对林权抵押贷款中涉及的理论基础、森林资源资产评估、贷款模式进行分析总结,对不同的森林资源所对应的资产评估和贷款模式进行了分类汇总。在林权抵押贷款实证研究汇总中,对林权抵押贷款的主要运行模式及其内容或特征进行了重点分析。讨论了目前关于林权抵押贷款研究存在的主要问题,认为我国林权抵押贷款的研究在基础理论、森林资源资产评估体系建立、抵押贷款的模式创新以及众学者提出的问题和对策针对性方面均有所欠缺,并提出了相应建议。  相似文献   

13.
Xishuangbanna has been largely transformed from biodiverse natural forests and mixed-use farms into monoculture rubber plantations in just twenty years. This conversion has expanded into forests previously protected by the community and onto marginal sites at high-elevation. Market-based ecosystem payments, especially carbon financing, are potential tools to prevent further forest loss in China. Here, we compare rubber net present value (NPV), carbon sequestration, and seed-plant species diversity for Xishuangbanna given three land-use scenarios: Business-As-Usual (BAU), Economic Oriented Scenario (EOS) and Conservation Oriented Scenario (COS) using a previously published spatial map of rubber profitability. The EOS achieved the greatest rubber profit but caused substantial reductions in natural forest area, biodiversity and carbon stocks. The EOS also requires substantial immigration of workers into a remote and ecologically important region with little social infrastructure for basic security, food security, health-care and education, causing frequently ignored costs. As expected, the COS will maintain the highest levels of natural forest area, sequester 57% more carbon, and 71% more biodiversity than EOS. Given the conservation value of the carbon stores and rich biodiversity residing in Xishuangbanna's natural forests, reducing rubber NPV only marginally would probably cost less than attempting to recover these resources. We recommend that rubber plantations be limited to established, productive lowland areas whilst protecting intact high-elevation forest and reforesting low-productivity plantations. These actions will enhance carbon sequestration and biodiversity conservation. Management policies focused solely on profits, like the EOS scenario, will fail to sustain the entire range of natural resources and ecosystem services. The prices in the carbon market would have to be considerably larger than they are currently to compete with the profitability of rubber.  相似文献   

14.
This paper assesses the impact of the ‘decoupling’ reform of the Common Agricultural Policy on the labour allocation decisions of Irish farmers. The agricultural household decision‐making model provides the conceptual and theoretical framework to examine the interaction between government subsidies and farmers’ time allocation decisions. The relationship postulated is that ‘decoupling’ of agricultural support from production would probably result in a decline in the return to farm labour but it would also lead to an increase in household wealth. The effect of these factors on how farmers allocate their time is tested empirically using labour participation and labour supply models. The models developed are sufficiently general for application elsewhere. The main findings for the Irish situation are that the decoupling of direct payments is likely to increase the probability of farmers participating in the off‐farm employment market and that the amount of time allocated to off‐farm work will increase.  相似文献   

15.
16.
Community forestry can deliver economic, socio-cultural, and ecological benefits to rural communities, yet criticisms have arisen that community forestry remains dominated by the decision-making of offsite experts and management techniques inappropriate for some communities. We use a case study approach to ascertain the needs, wants, and current realities of selected forest communities in Brazil and Mexico, to inform bottom-up approaches to community interventions. In identifying community-defined goals, we found that other livelihood strategies, particularly agricultural practices, need to be better integrated in the planning of forestry interventions overly focused on timber production. Site-specific intervention models need to take into account the variety of contexts and community interests, rather than replicating models that have been successful in other jurisdictions. A better understanding of local perspectives can aid in the design of community forestry interventions brought by conservation and development agencies, by adding an important and under-studied perspective to the problems that face community forestry.  相似文献   

17.
This paper presents a method for determining the subsidy required to motivate farmers to participate in timber afforestation programs designed to maximize social well-being. The method incorporates a carbon sequestration benefit function into the land expected value model in order to quantify the social benefit arising from carbon sequestration by the planted trees. This is used to calculate the optimal rotation age for newly planted forests that maximizes social utility. The minimum subsidy required to motivate farmers to participate in the afforestation program was calculated using a modified decision model that accounts for the subsidy's impact. The maximum subsidy offered by the government was taken to be the NPV of the carbon sequestration achieved by afforestation. Data on Robinia pseudoacacia L. trees planted on the Loess Plateau were used in an empirical test of the model, which in this case predicts an optimal subsidy of 254.38 yuan/ha over 40 years. This would guarantee the maintenance of forest on land designated for afforestation until they reached the socially optimal rotation age. The method presented herein offers a new framework for designing afforestation subsidy programs that account for the environmental service (specially, the carbon sequestration) provided by forests.  相似文献   

18.
This paper presents an econometric analysis of land‐cover change in western Honduras. Ground‐truthed satellite image analysis indicates that between 1987 and 1996, net forest regrowth occurred in the 1015 km2 study region. While some forest regrowth can be attributed to a 1987 ban on logging, the area of forest regrowth greatly exceeds that of previously clear‐cut areas. Further, new area was also deforested between 1987 and 1996. Thus, the observed land‐cover changes most likely represent a complex mosaic of changing land‐use patterns across time and space. Using satellite imagery from 1987, 1991 and 1996, we estimate a series of models, including binary probit models for each date, and a random‐effects probit model using panel techniques. We also experiment with spatial sampling schemes designed to reduce residual spatial autocorrelation, and qualitatively compare the impact of spatial sampling on model accuracy. Lastly, we find that changes in relative prices, infrastructure improvement, and topography are all significantly related to changing land‐cover patterns.  相似文献   

19.
林农合作形式多样性选择交易理论分析   总被引:1,自引:0,他引:1  
通过运用资产专用性、不确定性程度和交易频率三大交易维度,以及既定制度环境下的交换成本分析框架,分析集体林权制度主体改革后林农合作形式多样性选择的问题。结果表明,交易特性和费用是决定林农合作形式选择多样化的重要因素,以木材产品涉及的交易具有资产专用性强、不确定性高和交易频率低的特点,不同的林农合作形式具有不同的适应性。当前林农合作组织的发展应根据林农的选择和林产品类型,实施多样化的发展取向,政府则侧重提供保障制度空间,并从森林培育与营林技术的农村推广、农村森林经营方案的编制和林农合作组织森林保险制度的建设着手,降低森林经营固有的特性引起的交易费用。  相似文献   

20.
The objective of this study is to evaluate preferences for time paths of outputs arising from alternative forest management practices. A discrete choice framework using logit and mixed logit models is used to evaluate stated choices by Public Advisory Committee members over attributes regarding inter-temporal forest management options. Results of the study indicate a relatively strong preference for physical sustainability, or even flow choices. However, respondents appear to be more accepting of uneven flows in recreation services than they are of uneven flows of timber harvests. Results also provide yet another illustration of a difference in implied rates of discount over the goods involved (i. e. timber versus recreation). The paper illustrates a mechanism for use in public involvement exercises that may identify inter-temporal preferences over forest management plans and strategies.  相似文献   

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