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1.
In this study, we use two ecological forest models, namely FORMIX3 and FORREG, to analyse the impact of logging on tropical rain forests and to discuss needs for and problems of an economic extension of these models. The FORMIX3 model simulates spatial-temporal dynamics of tropical forests using an individual and process based approach. The main processes included are growth, mortality, competition, and regeneration of trees. The FORREG model simulates wood growth of tropical forests at landscape scale based on differential equations. Regeneration capabilities of logged forests are analysed and compared for different logging strategies. While conventional management strategies with a short logging cycle (here 20 years) produce low yields and cause severe changes in tree species composition, a reduced impact logging strategy with a longer cycle (here 60 years) leads to relatively high yields and causes moderate changes in species composition. Thus, longer logging cycles are preferable from an ecological point of view. However, also economic aspects influence logging decisions, thus a closer analysis of additional economic aspects of forest management is inevitable. We discuss which economic shortcomings of present rain forest models should be dealt with in the future and which additional data is needed as a consequence.  相似文献   

2.
This article aims to unbundle the influence of prevailing forestland rights institutions on the forest management behaviours of Vietnamese households. Based on a sample of 398 observations, we investigate the impact of two dimensions of forestland rights institutions (i.e. the formality and the duration) of two types of forest (i.e. production and protection forests) on two types of forest management behaviours (i.e. clearing and improving forest). We find that different dimensions of forestland rights institutions have different impacts on the forest management behaviour of households.  相似文献   

3.
森林除了具有经济价值和生态价值外,还具有基于生态系统服务功能所产生的社会效益价值。论文以云南省森林资源为例,采用房地产评估中常用的假设开发法为主要评估方法,结合森林资源所反映的社会效益价值增长特征,运用企业自由现金流量折现模型中的两阶段现金流折现模型,通过构建模型体系,分别从直接社会效益和间接社会效益两个维度对云南省森林资源的社会效益价值进行评估。其中,直接社会效益包括就业价值和景观游憩价值,间接社会效益包括科教价值、历史价值及文化价值,通过模糊综合评判计算各组成部分的不同影响权重得出直接和间接社会效益模型,以多元回归的方法构建森林生态总体社会效益价值模型并计算云南省森林社会效益价值。同时,将各部分价值结果分别与云南省第三产业GDP、人均GDP及云南省GDP进行对比分析,进而对云南省森林社会效益价值现有情况进行评价,并对今后的森林资源开发提出相关建议。  相似文献   

4.
This paper develops a framework for the valuation and management of tropical forests that reflects their ecological and economic characteristics. The analysis demonstrates the importance of modeling the feasible use patterns and the information structure in tropical forest management decisions. The model predicts that cases exist where the foresighted management of forests leads to more preservation than the traditional expected value approach. An application in Thailand provides evidence that such cases occur in relevant ranges of benefit flows. The model focuses tropical forest management on assessments of sustainability and feasible sequences in light of uncertainty and information flows.  相似文献   

5.
This paper discusses and contrasts two mainroles of forestry in light of the debate on theglobal climate. As the main problem is relatedto the increases of the CO2-concentrationin the atmosphere, forests may be viewed aspart of the alleviation of the problem throughtheir function as (i) a source of biomass forenergy production, which may replace fossilfuels and thus indirectly reduceCO2-emissions, and as (ii) carbon storage,since a growing forest extracts atmosphericCO2 and fixes it as carbon in biomass. Inthe Scandinavian forestry, logging residues areincreasingly being used for energy production.In this paper the value of forests as a sourceof bioenergy is added to the traditional timbervalue. Formulated as a joint production modelwithin the Faustmann framework, the effect ofthis addition on the optimal rotation length isdiscussed. Based on data for spruce, thedominant species in the Scandinavian forestry,it is demonstrated that the rotation length isshortened compared to the standard Faustmannmodel. Shorter rotation length implies lesscarbon storage. Therefore, in this modelwithout explicit regard to the social carbonstorage value of the forest, the gains in termsof the climate problem from utilisation offorest biomass for energy production are beingdiminished by the value of reduced carbonstorage. The carbon value of the forest is thenadded to complete the model, with the effect ofincreasing the rotation length, a result thatis well known in the literature. Finally, theempirical effects of the interaction of thesetwo climate-related value elements of theforest are discussed.  相似文献   

6.
Our main objective is to set out and apply a SEEA-based methodology to reflect the true value of forest resources in India's national and state accounts. We establish that a “top-down” approach using available national databases is both feasible and desirable from a policy perspective. In this paper, we address four components of value creation in forests: timber production, carbon storage, fuelwood usage, and the harvesting of non-timber forest products. The results of our analysis suggest that prevailing measures of national income in India underestimate the contribution of forests to income. The income accounts of the Northeastern states in particular are significantly understated by these traditional (GDP/GSDP) measures. We are also able to identify some states which performed poorly in the context of our sustainability framework, reflecting natural capital losses due to degradation and deforestation. Our results highlight the need to integrate natural resource accounting into the national accounting framework in order to generate appropriate signals for sustainable forest management and for the conservation of forest resources which are widely used by the poor in India, as well as being significant stores of national wealth.  相似文献   

7.
This study examines whether reciprocity is affected by what others know and do. Two types of social effects are investigated within the framework of a modified investment game. On the one hand, we assess the role played by the awareness that own choices are observed by another trustee—i.e., peer pressure. On the other hand, we measure the interaction between trustees’ choices—i.e., social spillovers. We find that peer pressure fosters reciprocity and, to a lesser extent, so do social spillovers.  相似文献   

8.
In seeking to value environmental amenities and public goods, individuals often have trouble trading off the (vague) good or amenity against a monetary measure. Valuation in these circumstances can best be described as fuzzy in terms of the amenity being valued, perceptions of property rights, and the numbers chosen to reflect values. In this paper, we apply fuzzy logic to contingent valuation, employing a fuzzy clustering approach for incorporating preference uncertainty obtained from a follow-up certainty confidence question. We develop a fuzzy random utility maximization (FRUM) framework where the perceived utility of each individual is fuzzy in the sense that an individual’s utility belongs to each cluster to some degree. The model is then applied to a Swedish survey that elicited residents’ willingness to pay for enhanced forest conservation and to a Canadian survey of agricultural landowners that elicited their willingness to accept compensation for a tree planting program. Both the WTP and WTA measures we obtain using the fuzzy approach are well below those obtained using standard probability methods. Based on goodness of fit measures and Monte Carlo experimentation, a case can be made for using a fuzzy preference approach for modeling preference uncertainty as opposed to incorporating respondent uncertainty within the random utility maximization framework.   相似文献   

9.
ABSTRACT

Insecure, contested, and unjust forest tenure arrangements undermine forest investment and protection, fuel conflict, and jeopardize Indigenous Peoples’, local communities’, and indigenous and community women’s rights, livelihoods, and development prospects. While legally recognized community forests tend to have lower rates of deforestation, store more carbon and benefit more people than forests managed by either public or private entities, evidence shows over two-thirds of forests remain controlled by governments – a significant portion of which is contested by indigenous and local communities who traditionally own, manage, and depend on these forests. It is therefore all the more critical that governments support and advance communities’ forest tenure rights. Using longitudinal tenure data and analysis of global forest ownership trends developed by the Rights and Resources Initiative, this article details the distribution of statutory forest rights across 58 countries covering nearly 92% of global forests over the fifteen-year period from 2002–2017.  相似文献   

10.
This study presents an applied improvement in the agroforestry accounting system (AAS) approach to two public cork oak forests in the Mediterranean region: Jerez (Spain) and Iteimia (Tunisia). Both forests have similar environments but differ in land property rights, labour markets and countries (developed and developing economy, respectively).The income analysis considers the differences between forest ownership, and household and landowner economic rationalities. In the case of Jerez, the public landowner has a right to exclude others from using the forest resources; community employment and natural resource conservation criteria determine Jerez's management. In the Iteimia case, the public landowner has regulated free-use rights for livestock grazing, firewood and crops so that local households can meet their needs and improve their income. Households operate by maximizing their income from the full employment of their own family workforce.The results show that Jerez's management generates negative commercial capital income for the public landowner, despite receiving significant public subsidies, while it maintains high internal forestry investment that generates additional local employment. Conversely, Iteimia produces positive commercial capital income for the public landowner and high household self-employed labour income per hectare.  相似文献   

11.
The Faustmann forest rotation model is a celebrated contribution in economics. The model provides a forest value expression and allows a solution to the optimal rotation problem valid for perpetual rotations of even-aged forest stands. However, continuous forest cover forest management systems imply uneven-aged dynamics, and while a number of numerical studies have analysed specific continuous cover forest ecosystems in search of optimal management regimes, no one has tried to capture key dynamics of continuous cover forestry in simple mathematical models. In this paper we develop a simple, but rigorous mathematical model of the continuous cover forest, which strictly focuses on the area use dynamics that such an uneven-aged forest must have in equilibrium. This implies explicitly accounting for area reallocation and for weighting the productivity of each age class by the area occupied. We present results for unrestricted as well as area-restricted versions of the models. We find that land values are unambiguously higher in the continuous cover forest models compared with the even-aged models. Under area restrictions, the optimal rotation age in a continuous cover forest model is unambiguously lower than the corresponding area restricted Faustmann solution, while the result for the area unrestricted model is ambiguous.  相似文献   

12.
《Ecological Economics》2007,63(3-4):661-672
We develop an endogenous sample selection model to investigate how forest dependence influences a household's decision to participate in forest co-management program. Using data from Chimaliro and Liwonde forest reserves in Malawi, we find that where forests primarily have a gap filling or safety net role in Chimaliro, high forest dependency induces higher rates of participation. However, with more commercial forest uses and a more heterogeneous social context as in Liwonde, high forest dependency reduces the incentives for participation. The findings point to the need to design parallel interventions alongside the forest co-management program in order to provide supplementary income sources to participants and increase the incentives for participation.  相似文献   

13.
This paper presents a bottom-up methodological framework for estimating some of the key ecosystem services provided by forests biomes worldwide. We consider the provision of wood and non-wood forest products, recreation and passive use services, and carbon sequestration. The valuation framework derives per hectare estimates by applying meta-analysis, value-transfer and scaling-up procedures in order to control for the existing heterogeneities across world regions and forest biomes. The first part of the study estimates stock values per hectare for each forest ecosystem service in the baseline year 2000 and in the year 2050. Results differ per geographical region and biome. Carbon stocks represent, on average, the highest value per hectare, followed by provisioning services, passive use and recreational values respectively. The second part provides an estimation of the welfare loss (or gain) associated with policy inaction in the period 2000–2050 leading to a change in the forest area. Welfare results are mixed and require a careful interpretation, ranging from a worldwide annual benefit of + 0.03% of 2050 GDP to an annual loss of −0.13%. The highest damage is expected in Brazil due to the increasing deforestation taking place in tropical natural forests, which is causing a considerable loss of carbon stocks.  相似文献   

14.
集体林区生态公益林产权市场化探讨   总被引:1,自引:0,他引:1  
在阐述生态公益林产权市场化可能的类型的基础上,分析当前阻碍集体林区生态公益林产权市场运行的主要因素,提出促进生态公益林产权市场化运行的对策建议,主要包括明晰和优化公益林产权,加强公益林生态服务功能价值评估,创建有利于公益林产权市场发展的外部环境。  相似文献   

15.
本文回顾了改革开放以来国有林业企业管理体制的演变 ,通过多任务委托代理模型探讨了这一演变过程中利润分成和采伐限额两个不相容的政府政策激励对国有林业企业经营者激励的影响 ,特别是信息不对称条件下其对木材采伐的影响 ,从而解释了国有林业企业普遍存在的超限额采伐的经济原因。通过全国 2 8个省 5次全国森林资源普查的面板数据 ,通过使用国有林业企业的平均面积作为政府与国有林业企业委托—代理关系中信息不对称的代理变量 ,从实证上验证了信息不对称将会导致超限额采伐和国有林资源增长率下降的假说  相似文献   

16.
Nepal has a long history of returning public forests to local people as part of its community forestry programme. In principle the community forestry programme is designed to address both environmental quality and poverty alleviation. However, concern has been expressed that forest policies emphasise environmental conservation, and that this has a detrimental impact on the use of community forests in rural Nepal where households require access to public forest products to sustain livelihoods. To study the effect of government policies on forest use, an economic model of a typical small community of economically heterogeneous households in Nepal was developed. The model incorporates a link between private agriculture and public forest resources, and uses this link to assess the socioeconomic impacts of forest policies on the use of public forests. Socioeconomic impacts were measured in terms of household income, employment and income inequality. The results show that some forest policies have a negative economic impact, and the impacts are more serious than those reported by other studies. This study shows that existing forest policies reduce household income and employment, and widen income inequalities within communities, compared to alternative policies. Certain forest policies even constrain the poorest households?? ability to meet survival needs. The findings indicate that the socioeconomic impacts of public forest policies may be underestimated in developing countries unless household economic heterogeneity and forestry??s contribution to production are accounted for. The study also demonstrates that alternative policies for managing common property resources would reduce income inequalities in rural Nepalese communities and lift incomes and employment to a level where even the poorest households could meet their basic needs.  相似文献   

17.
Insufficient sensitivity to scope (variations in the scale of the environmental good on offer) remains a major criticism of stated preference methods, and many studies fail a scope test of some sort. Across a range of existing explanations for insensitivity to scope (commodity mis-specification, embedding, warm glows) there seems to exist no clear conclusion on how to deal with the problem. This paper provides an alternative explanation for insufficient sensitivity to scope, based on re-definition of the determinants of value for environmental goods within an attributes-based choice model. In the proposed framework respondents’ Willingness To Pay need depend not only on physical characteristics of a good, but may also depend on the ‘label’ under which the environmental good is ‘sold’ in the hypothetical market. To investigate this problem, a Choice Experiment study of biodiversity was conducted. We find that controlling for the effects of a label—in this case, national park designation—leads to significant increase in the scope sensitivity of welfare measures.  相似文献   

18.
We analyse a large Bayesian Vector Autoregression (BVAR) containing almost 100 New Zealand macroeconomic time series. Methods for allowing multiple blocks of equations with block-specific Bayesian priors are described, and forecasting results show that our model compares favourably to a range of other time series models. Examining the impulse responses to a monetary policy shock and to two less conventional shocks—net migration and the climate—we highlight the usefulness of the large BVAR in analysing shock transmission.  相似文献   

19.
我国山岳型森林公园的类型可以按山体海拔高度、组成山体的岩性特征和地貌类型划分。以广东省为例,省内山岳型森林公园的特征主要表现在风景资源多姿多彩,以森林景观为主体,地文、天象、水文和人文等景观资源组合度好,自然景观引入入胜,区域环境质量优越、旅游开发潜力较强。在开发过程中,应注意合理规划,挖掘特色,遵循人与自然和谐以及可持续发展的原则,处理好资源开发与资源环境保护的关系。  相似文献   

20.
This paper aims to identify the relationship between economic growth and forest cover change in Sichuan, China. Using a set of panel land use data based on Landsat TM/ETM digital images, we show that during the late 1980s and 1990s, Sichuan’s forest cover initially decreased and then rose. We also note that the rising and falling trends occurred at the same time that Sichuan’s economy was going through a period of rapid and sustained growth. We use multivariate analysis to identify the determinants of forest cover change. In addition to using a first-differenced estimator, we also utilize spatial error and spatial lag models to obtain consistent and efficient estimates of the determinants of forest cover. Our analysis demonstrates the importance of economic growth on the forest cover change; the results show that there is a U-shaped relationship between forest cover and GDP per capita. However, despite the nature of the empirical relationship between forest cover and income, the high turning point of the U-shaped relationship suggests that there is no evidence for the existence of the Environmental Kuznets Curve for forests in Sichuan Province. Hence, policy interventions may be necessary to stop the decrease of forests.  相似文献   

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