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1.
This research evaluates the potential gains in benefits from using Goal Programming to preserve forestland. Two- and three-dimensional Goal Programming models are developed and applied to data from applicants to the U.S. Forest Service's Forest Legacy Program, the largest forest protection program in the United States. Results suggest that not only do these model yield substantial increases in benefits, but by being able to account for both environmental benefits and in-kind partner cost share, Goal Programming may be flexible enough to facilitate adoption by program managers needing to account for both ecological and political factors.  相似文献   

2.
In Central Africa, creating forest roads and skid trails is one of the most costly and environmentally damaging operations for the forest's ecosystem. An optimized road network is essential for reducing construction costs and improving the sustainable management of timber resources. The location of landings is vital in the development of a future forest road network. In this study, a binary integer programming model similar to the uncapacitated facility location problem is formulated to optimize the locations of the landings. The model is applied to selective logging in Central Africa and tested on an annual logging zone in Southeast Cameroon. The results are compared to that of manual road planning, the currently used method.  相似文献   

3.
Forest fires and forest biodiversity are related issues of major concern in Mediterranean countries and require an integrated approach to landscape planning. The aim of this study was to develop a GIS approach for regulating forest production while promoting landscape diversity and mitigating fire hazard. A study area located in the centre of Portugal was chosen. The area was primarily occupied by maritime pine and had a high fire hazard, low tree species diversity and an extensive protection area. The classical area control method was used to assist in forest production regulation. Species suitability maps were produced for 21 recommended species for afforestation in the study area. Maritime pine management compartments were defined, and a 50-year harvesting plan was proposed. In each harvested compartment, protection areas were identified for species conversion (e.g., native oaks and/or broadleaves). Afforestation species were proposed according to the species suitability maps produced earlier. Low flammability species that produce high-quality wood, non-wood products and landscape enhancement were preferred. A comparison of the land cover in the study area in 2007 to that anticipated in 2064 via the proposed plan showed that a more fragmented landscape structure could be achieved by introducing 16 species of lower flammability than maritime pine into the study area. This study proved the usefulness of this methodological approach for guiding sustainable changes in homogeneous, unmanaged forest landscapes prone to fire. Further research is needed regarding integrated planning approaches that incorporate environmental, economic and social dimensions (e.g., human desertification of rural areas).  相似文献   

4.
In deciding to keep or fell a forest stand given its age, the risk of loss of timber through wildfire is an important consideration. If trees also have value from sequestration of carbon, another effect of fire is the unplanned loss of stored carbon. Factors affecting the decision to keep or fell trees, and how much to spend on fire protection, are investigated using stochastic dynamic programming, using carbon sequestration in stands of mountain ash in Victoria as a case study. The effect of treating sawlogs as a permanent carbon sink after harvesting is explored.  相似文献   

5.
In this paper, we developed a mixed-integer non-linear programming model that integrates access road development and a utility theoretic spatial choice model of hunters into a strategic forest harvest-scheduling model. The model was applied to an operationally sized Forest Management Agreement (FMA) area in central Alberta, Canada. The resulting behavioral model had approximately 2.6 million decision variables and about 96,000 constraints, and was used to examine the impacts of timber harvesting on hunters’ preference for hunting sites. We also evaluated the impacts of various levels of hunter welfare on: (i) the degree of tradeoff between timber and hunting benefits, (ii) timber harvest schedules, and (iii) the marginal costs of producing timber products. The results showed significant tradeoffs between timber and hunting benefits and a clear link between landscape characteristics and changes and behavioral responses by hunters.  相似文献   

6.
An important issue in the design of stated-preference surveys is whether the information provided to respondents within a survey instrument is adequate to yield valid value estimates. Providing respondents with on-site experience about forest ecosystem management alternatives may influence their expectation of the effects from new policies and programs. In the research reported here, we investigate whether preference parameters for attributes of low-impact timber harvesting programs differ between respondents to a mail survey versus respondents provided with an on-site forest experience (walk through a research forest). The empirical analysis in our application shows that stated preferences for timber harvesting attributes are not statistically different between the mail and on-site applications of the survey, and this result is robust to pretest (before experience) and post-test (post experience) applications.  相似文献   

7.
内蒙古大兴安岭森林采伐量锐减,为了有效地解决问题,林区应该根据自身发展的需要,把赴俄采伐作为森工企业的发展项目,坚持"走出去"的发展战略,整合现有对俄采伐加工项目,建立统一管理的赴俄采伐机构,实行股份合作制经营,走规模化经营发展之路,扩大赴俄合作采伐的生产规模,真正促进赴俄采伐产业的健康有序发展。针对内蒙古大兴安岭林区发展赴俄采伐产业实际进行分析,提出了相应的意见和建议。  相似文献   

8.
This study estimates the supply potential and annual availability of timber and forest biomass resources under profitable forest management in Japan. It focuses on four prefectures, namely, Fukushima, Ibaraki, Tochigi, and Gunma, and considers the trade between these prefectures. Production forests were extracted as subcompartments where the expected revenues surpassed all costs, from planting to final harvest. To estimate harvesting costs, appropriate harvesting systems were determined according to each prefecture’s topographical features. The log markets and woody biomass power generation plants were assumed to be the destinations for timber and forest biomass resources. Annual availability from the Cut-To-Length (CTL) system, consisting of the use of harvesters and forwarders, accounted for 58 % of the total availability, even though the supply potential from CTL was only 15 %; this is because CTL is the most productive and least expensive harvesting system. Then, the effects of subsidies on availability are examined. Availability under an additional regeneration subsidy meets almost the entire current demand in this region. Furthermore, availability with a thinning subsidy can meet the forecasted future demand in this region, while availability with both thinning and additional regeneration subsidies can meet future demand in all prefectures analyzed in the present study. Thus, subsidies play an important role in the profitability of forestry operations as well as the supply of timber and forest biomass resources in Japan.  相似文献   

9.
10.
Our purpose is to estimate a model of non-industrial forest landowner behavior that considers certain types of behavior that have escaped discussion and rigorous investigation in the literature, yet which are critical to future policy making. Our focus on the many different but related decisions landowners make broadens the typical understanding of landowner behavior to show how bequest motives, debt and participation in non-timber activities, and harvesting decisions are interrelated and dependent on landowner preferences, market, and land characteristics.  相似文献   

11.
We examine the intensity of harvesting decision by non-industrial landowners at the lowest price offer they deem acceptable, using a multiple bounded discrete choice stated preference approach that draws upon and connects two subfields of forestry, one identifying characteristics of landowners important to past harvesting or reforestation decisions, and another proposing how landowners evaluate price offers for forest harvesting decisions. Variables important to harvest intensity choices when the landowners find an acceptable price have only been considered for those landowners who actually have participated in harvesting markets, whereas here we examine the behavior of these individuals as well as those who are on the margin (i.e., have not harvested at prevailing current or past market prices). We show that harvest intensity depends critically on the extent of urbanization, indicated by the presence of structures on a parcel as well as forested tract size, along with landowner characteristics such as absenteeism and length of ownership. The results are useful for understanding the timber management behavior for a majority of landowners who may not harvest at prevailing prices, but may participate should prices reach a level acceptable to them, where this level is determined by individual preferences for standing timber resources.  相似文献   

12.
In Washington State, small forest landowners (SFLO) play an important role in maintaining forest cover on the landscape as well as associated ecosystem services. This paper examines landowner preferences for the attributes of working forest conservation contracts (WFCC) using a choice experiment. The attributes examined are contract duration (from 10 years to perpetuity), forest management requirements, and the extent of forestland covered under the contract. We find that contract attributes are valued very differently depending on landowner objectives and harvesting behavior. Landowner characteristics and forestland spatial characteristics including distances to development and large public forestlands were found to significantly influence the likelihood of contract acceptance. While a significant portion of preference heterogeneity remains unobserved, we identify several key sources of landowner preference heterogeneity which allows for a better understanding of which landowners are likely to enroll in voluntary forest conservation contracts and may have implications for improved targeting of contracts.  相似文献   

13.
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   

14.
Tropical deforestation and forest degradation are among the top global threats to biodiversity, carbon storage and rural livelihoods, but the social processes underlying these changes remain difficult to observe across large spatial scales and in data-poor contexts such as tropical Africa. We link longitudinal survey data from agricultural households in rural Uganda to high-resolution satellite data on forest cover change, and use this linked dataset to investigate processes at two scales: tree planting and harvesting at the parcel scale, and deforestation and reforestation at the community scale. This multi-scale analysis reveals that tree planting is more common on parcels with secure tenure, by educated heads and in isolated communities. Deforestation is highest in land-rich, agrarian communities with low population density and high baseline forest cover. These results provide explicit evidence that the social drivers of forest change in Uganda vary across scales, indicating a need for additional multi-scale studies.  相似文献   

15.
Collaborative planning has become an increasingly popular approach in environmental decision-making, particularly in situations where there are multiple actors with conflicting interests. In this paper, collaborative environmental planning is perceived as being embedded in an institutional environment that has an impact on the processes and outcomes of planning. Building on the theory of new institutionalism, the paper combines legal analysis of forest regulation with interviews and policy document data from two case studies on collaborative Natural Resource Planning in state-owned forests in Finland. These approaches will be used to analyse how formal regulations and informal norms are interpreted and implemented in the planning processes. The paper highlights the important role institutions can play in promoting or hindering successful collaborative planning, and makes recommendations for developing a forest governance system that is equipped to deal with the identified challenges.  相似文献   

16.
Forest loss and fragmentation, which generate various negative environmental and ecological consequences, have become widespread phenomena across the globe. Motivation to investigate the underlying drivers is essential for land use planning and policy decision making. This paper characterizes forest loss and fragmentation from 1979 to 2014 in the Ningbo region (China) using multitemporal satellite imageries and a set of landscape metrics (area-weighted mean patch area, edge density, area-weighted shape index, Euclidean nearest neighbor distance, effective mesh size and total area); and then quantifies the responsible socioeconomic drivers (economy, social activities, science and technology, culture and policy, demography) under different land use planning schemes (urban and non-urban) using multivariate linear regression. Results show that the two zones present identical trend of intensifying forest loss and fragmentation but differ in changing magnitude and speed. More specifically, forest loss and fragmentation in the non-urban planning zone occurs at a significantly higher pace and magnitude. For the urban planning zone, population pressure, economic growth and fruit consumption are the primary drivers of forest loss, while forest fragmentation is mainly driven by economic openness, cash crop consumption and environmental protection consciousness. For the non-urban planning zone, income increases, fruit consumption and infrastructure development are the primary drivers of forest loss, while infrastructure and tourism development are the major drivers of forest fragmentation. Besides, forest loss and fragmentation in the two zones are both heavily subjected to land use policy. The variance partitioning analysis highlights that the policy driver is the most influential one and economic driver also has strong effect on forest loss and fragmentation in the urban planning zone. For the non-urban planning zone, the influence of policy driver is the strongest and social activity is also very powerful. These results provide compelling evidence that land use planning fails to play an efficient role in protecting forest resources in the Ningbo region. The failure should be attributed to several issues associated with land use planning and forestry governance that widely exist in China. We finally propose some pertinent implications and suggestions for China’s land use planning and forest policy. This study is believed to advance the understanding of the socioeconomic drivers of forest loss and fragmentation. It therefore provides some new insights in land use policy.  相似文献   

17.
This article explores the question under which conditions trees are managed in even- or uneven-aged stands or age class forests, respectively. The problem of uneven-aged management within stands and forests can be reduced to the analysis of simultaneous optimal times of harvest and regeneration of interdependently growing trees. Restricting attention to a market environment, a forest investment model is developed which accounts for the opportunity to manage trees or stands individually. As a consequence, age class forests evolve as the optimal compromise between two opposing effects. They allow for a combination of the advantages of uneven-aged management by utilizing differences in tree growth on a larger scale and of even-aged management by exploiting locally effective positive inter-tree dependencies on a smaller scale. Accordingly, the emergence of the forest structure is determined by the dynamics in the balance of value growth and impact rate differences.  相似文献   

18.
湖南省紧紧围绕国家林业局采伐管理改革具体部署:推进采伐分类管理,使采伐管理范围更加明确;编制森林经营方案,使限额管理更加科学;创新分配机制,使采伐指标分配更加公平;简化审批程序,使采伐指标申请更加便捷;加强监督管理,使采伐秩序更加规范。  相似文献   

19.
Road development in mountainous forestlands can lead to naturally formed slopes being disturbed. Efficient planning methodologies can assist forest engineers in either preventing or reducing the environmental impacts of forest roads. In this study, we first prepared an inclusive landslide susceptibility map for our study area using a Bayesian model. We next designed 12 road network alternatives using PEGGER, an ArcView GIS extension. We extracted the values of these alternatives from the susceptibility map to evaluate their environmental feasibility. We also evaluated the alternatives from an economic perspective using a model for conducting cost estimates of the forest roads. Our results show that this approach is useful for identifying the alternative that meets environmental and economic goals. The policy implications of this study suggest that if the development of road networks in mountainous areas is an important forestry goal, mechanisms should be aimed primarily at controlling slope instability.  相似文献   

20.
土地利用总体规划滚动调整中递推规划方法的应用   总被引:2,自引:0,他引:2  
文章从土地利用总体规划的特性入手,系统阐述其滚动调整的必要性、作用机理和操作程序,重点介绍土地利用总体规划滚动调整中的递推规划模型和时间序列模型的具体应用。为土地利用总体规划实施提供一种新的方法思路。  相似文献   

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