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1.
This paper deals with the forest owner’s attitude towards risk and the harvesting decision in several ways. First, we propose to characterize and quantify the forest owner’s attitude towards risk. Second, we analyze the determinants of the forest owner’s risk attitude. Finally, we determine the impact of the forest owner’s risk attitude on the harvesting decision. The French forest owner’s risk attitude is tackled by implementing a questionnaire, including a context-free measure borrowed from experimental economics. The determinants of the forest owner’s risk attitude and harvesting decision are estimated through a recursive bivariate ordered probit model. We show that French forest owners are characterized by a relative risk aversion coefficient close to 1 with a DARA assumption. In addition, we find that the forest owner’s risk aversion is influenced positively and significantly by the level of risk exposure, the geographical location of the forest and the fact to be a forester, and negatively by the income. Finally, we obtain that the forest owner’s risk aversion has a positive and significant impact on the harvesting decision.  相似文献   

2.
Given the importance of anthropogenic determinants in forest ecosystems within Europe, the objective of this paper is to link the evidence arising from biological models to socio-economic determinants, where the expected returns of forest investments represent the main driver. A micro-economic area allocation module is therefore coupled with an inventory-based forest dynamics module and a partial-equilibrium market module in a national-level forest sector model for France (FFSM++). Running long-term scenarios (until 2100), we show the implication of an active management policy on forest composition: when the most profitable option drives forest investments, coniferous forests are generally preferred over broadleaved ones. This result is, however, reappraised when the risk aversion of forest owners is explicitly considered in the model, given the higher risk associated with the former. We further show the strong stability of forest ecosystems that, due to the very long cycles, undergoes very small variations in volume stocks, even in scenarios where the initial forest regeneration is strongly influenced.  相似文献   

3.
Monitoring Sustainable Forest Management in Different Jurisdictions   总被引:1,自引:0,他引:1  
The concept of sustainable forest management (SFM) requires forest resource managers to monitor and collect information pertaining to their environmental, economic and social impact. There are increasing expectations from a variety of publics (government, customers, and other stakeholders) that forests be demonstrably well-managed, creating incentives for forest managers to design credible systems for assessing their management performance. It is against this background that local, national and international approaches to regulating forest practices have been evolving. This article reviews the different dimensions of governance as they relate to monitoring and information reporting in the forest sector. Specifically, it discusses the changing role of sovereignty, the effects of globalization and the emergence of civil society stakeholders in forestry-related decision-making. Concepts such as sovereignty and globalization have important implications for monitoring forest practices and for defining SFM. Whether SFM standard creation and enforcement involves a sovereign, shared-sovereignty or civil society approach will affect the level and nature of SFM monitoring. As a result, we need to better consider the concept of monitoring appropriate to the scale and intensity of operations, how monitoring and information reporting standards differ between jurisdictions, and what this means for independently verifying SFM at an inter-jurisdictional level.  相似文献   

4.
Forest management practices alter forest structure quantified with ecosystem characteristics and values. In this paper, we utilized a forest management simulation model to assess the effects of three forest management strategies focusing on timber production, carbon sequestration, oxygen production, soil erosion, and water production of a forest management unit in Turkey. A forest simulation model “ETÇAPSimülasyon” was developed and used to project forest ecosystem development over 100 years under three forest management policies of timber-oriented forest management (TFM), multipurpose forest management (MFM), and no intervention (NI). The results showed that TFM strategy produced more timber and its net present value than MFM and NI strategies did. The amount of carbon sequestration and oxygen production potential was also found to be the highest with TFM strategy than with the MFM and NI strategies. Compared with the other strategies, however, NI strategy produced the highest amount of water production and soil losses over the planning horizon. The effects of a forest management strategy depend mainly on the initial forest structure, the rate of development and the level of forest management interventions. Therefore, forest dynamics under various management strategies should be explained before the final management decision. Understanding long-term effects of any management strategies on forest structure will provide the basis for better reaching the management objectives.  相似文献   

5.
The objective of this study is to integrate agent-based modeling and geographic information systems (GIS) for examining how interactions within forest management lead to patterns of land-cover change. Specifically, this study evaluates how management agents behave in the presence of variable timber prices, harvesting costs, and accessibility to timber and how their actions influence the spatial characteristics of the forest landscape over time. The GIS calculates the average harvested patch size, number of patches, and total harvested area as measures of emergent patterns resulting from agent actions. The results from the agent-based GIS model reveal that good economic conditions lead to few but large harvested patches, while deteriorating conditions will see more patches of smaller size if forest companies have access to high-quality timber. This study emphasizes the need for a complex systems approach to forest management as the model illustrates how system elements interact in a manner to produce emergent spatial patterns over time.  相似文献   

6.
Currently, the integration of carbon and water values of forest ecosystems into forest management planning models has become increasingly important in sustainable forest management. This study focuses on developing a multiple-use forest management planning model to examine the interactions of timber and water production as well as net carbon sequestration in a forest ecosystem. Each forest value is functionally linked to stand structure and quantified economically. A number of forest management planning strategies varying in the amount of water, carbon, and timber targets and flows as constraints are developed and implemented in a linear programming (LP) environment. The outputs of each strategy are evaluated with a number of performance indicators such as standing timber volume, ending forest inventory, area harvested, and net present value (NPV) of water, timber, and carbon over time. Results showed that the cycling time of forest stands for renewal has important implications for timber, water, and carbon values. The management strategies indicated that net carbon sequestration can be attained at a significant cost in terms of foregone timber harvest and financial returns. The standing timber volumes and ending forest inventories were among the most important factors determining whether the forest constitutes a net carbon sink or source. Finally, the interactions among the forest values were generally found to be complementary, yet sometimes contradictory (i.e., negatively affecting each other), depending on the assumed relationship between forest values and stand structure.  相似文献   

7.
Criteria and Indicators of Sustainable Forest Management   总被引:2,自引:0,他引:2  
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8.
Effects of Forest Management Practices on Mid-Atlantic Streams   总被引:1,自引:0,他引:1  
Agricultural and urban land use activities have affected stream ecosystems throughout the mid-Atlantic region. However, over 60% of the mid-Atlantic region is forested. A study was conducted to investigate the effects of management practices on forested stream ecosystems throughout the mid-Atlantic region. The study consisted of two phases: Phase 1 was a literature synthesis of information available on the effects of forest management practices on stream hydrology, erosion and sedimentation, riparian habitat alteration, chemical addition, and change in biotic diversity in the mid-Atlantic region. In Phase 2, data from mid-Atlantic streams were analyzed to assess the effects of forest land use on stream quality at the regional scale. Typically, it is the larger order streams in which monitoring and assessment occurs—3rd order or higher streams. The impacts of forest management practices, particularly hydrologic modifications and riparian buffer zone alteration, occur predominantly in first and second order streams with cumulative impacts translating to higher order streams. Based on the literature review and mid-Atlantic Highland streams analysis, there are short-term (e.g., 2 to 5 years) effects of forest management practices on stream quality at local scales. However, signatures of cumulative effects from forest management practices are not apparent at regional scales in the Highlands. In general, forested land use is associated with good stream quality in the region compared with other land use practices.  相似文献   

9.
Understanding the historical dynamics, composition, and environmental disturbances of forest landscapes provides a context for monitoring changes, describing trends, and establishing reference conditions. This study analyses the temporal changes in forest ecosystem structure in Artvin Forest Planning Unit (AFPU), Turkey, during 1972–2002 period based on digitized forest stand type maps using geographic information system (GIS) and interpretation of satellite data. The results showed that there was a net decrease of 450 ha in total forested areas between 1972 and 2002. Forest ecosystem structure changed over time depending on a few factors such as demographic movements, insect outbreaks, dam and road construction, unregulated management actions, and social pressure. In conclusion, temporal changes and the factors affecting these changes should be determined for sustainable management of natural resources.  相似文献   

10.
Part of this paper has been prepared for the lecture Forest Health Assessment-Criteria,Methods and Problems given by the author at the UIMPuniversity course Sanidad Forestal en el Bosques Mediterraneos yTemplados. Implicacion de la Contaminacion Atmosferica y del Cambio Global, held in Valencia, Spain, October, 1995. Assessment and monitoring of forest health representsa key point for environmental policy and for the management ofenvironmental resources. With the renewed interest in assessment andmonitoring of forest health generated by the suspected occurrence ofa widespread forest decline in Europe and North America, manyactivities have been undertaken: however, some questions should beconsidered and clarified when attempting to estimate forest health.Particularly, the objective(s) of the assessment and monitoringprogram should be carefully identified. Identification of a program‘stask has a number of implications and consequences: it implies adefinition of what concept of forest health (forest ecosystem health,forest health or forest trees health?) is assumed, what will be thetarget entity to be monitored, and therefore the identification of therelevant assessment questions and assessment endpoints.Consequences concern the definition of the spatial scale (frominternational to landscape and plot scale monitoring) and ecologicalcoverage (from single species population to population ofecosystems) of the program, which can have a considerable influenceon the choice of the proper sampling strategy and tactic, as well ason the most suitable methods, indicators and indices to be used.Although much of the work in the field of forest health and airpollution has concentrated on surveys on crown transparency anddiscoloration, there is an entire range of methods, indicators andindices developed to assess the health status of forests. The decisionas to which ones should be used will depend on the aim of theprogram and on economic and practical considerations. A furtherconsideration concerns the time span of the program, but anydecision in this field is subject to many limitations due to difficultiesin predicting future monitoring needs. All these points should becarefully considered and implemented according to a rigorousQuality Assurance procedure since any decision will influence futurework for many years.  相似文献   

11.
Invasive species pose a significant threat to global biodiversity. Managing invasive species often involves modeling the species’ spread pattern, estimating control costs and damage costs due to the invasion, designing control efforts, and accounting for uncertainties in model parameters. Dealing with uncertainty is arguably the most important part of the process, since biological, environmental, and economic factors can cause parameter values to vary greatly. Managers need decision tools that are robust to such limited or variable information. Here, we present a robust spatial optimization model to select treatment sites in a way that maximally reduces the size of an invasive population, given a constraint on financial resources. We develop an integer programming model that includes population dynamics and management costs over space and time. The model incorporates uncertainty in the available budget and the invasive spread rate as sets of discrete scenarios to determine a robust, cost-effective management plan in a novel way.  相似文献   

12.
In natural boreal forests, disturbances such as fire and variation in surficial deposits create a mosaic of forest stands with different species composition and age. At the landscape level, this variety of stands can be considered as the natural mosaic diversity. In this paper, we describe a model that can be used to estimate the natural diversity level of landscapes. We sampled 624 stands for tree species composition and surficial deposits in eight stand-age classes corresponding to eight fire episodes in the region of Lake Duparquet, Abitibi, Québec at the southern fringe of the Boreal Forest. For six surficial deposit types, stand composition data were used to define equations for vegetation changes with time for a chronosequence of 230 years for four forest types. Using Van Wagner's (1978) model of age class distribution of stands, the proportion of each forest type for several lengths of fire cycle were defined. Finally, for real landscapes (ecological districts) of the ecological region of the Basses-Terres d'Amos, the proportion of forest types were weighted by the proportion of each surficial deposit type using ecological map information. Examples of the possible uses of the model for management purposes, such as biodiversity conservation and comparisons of different landscapes in terms of diversity and sensitivity to fire regime changes, are discussed.  相似文献   

13.
Forests make up large ecosystems and can play an important role in mitigating the emissions of CO2, the most important greenhouse gas. However, they are sources of atmospheric carbon when they are disturbed by human or natural causes. Storage of carbon through expansion and adaptive management of forest ecosystems can assist in reducing carbon concentrations in atmosphere. This study proposes a methodology to produce spatially explicit estimates of the carbon storages (aboveground plus belowground) depending on land use/cover changes in two different forest ecosystems during various periods. Carbon storages for each forest ecosystem were projected according to inventory data, and carbon storages were mapped in a geographic information system (GIS). Results showed that total carbon stored in above and belowground of both forest ecosystems increased from one period to other because of especially increase of productive forest areas and decline of degraded forest areas as well as protection of spruce forests subject to insect attacks.  相似文献   

14.
The National Environmental Policy Act (NEPA) requires U.S. Forest Service planning processes to be conducted by interdisciplinary teams of resource specialists to analyze and disclose the likely environmental impacts of proposed natural resource management actions on Forest Service lands. Multiple challenges associated with these processes have been a source of frustration for the agency. One of these challenges involves administrative appeals through which public entities can challenge a Forest Service decision following a NEPA process. These appeals instigate an internal review process and can result in an affirmation of the Forest Service decision, a reversal of that decision, or additional work that re-initiates all or part of the NEPA process. We examine the best predictors of appeals and their outcomes on a representative sample of 489 Forest Service NEPA processes that were decided between 2007 and 2009. While certain factors associated with pre-existing social contexts (such as a history of controversy) or pre-determined elements of a proposed action (such as the extraction of forest products) predispose certain processes to a higher risk of appeals, other practices and process-related strategies within the control of the agency also appear to bear meaningful influence on the occurrence of appeals and their outcomes. Appeals and their outcomes were most strongly related to programmatic, structural (turnover of personnel in particular), and relationship risks (both internal and external) within the processes, suggesting the need for greater focus within the agency on cultivating positive internal and external relationships to manage the risk of appeals.  相似文献   

15.
The production of timber from native forests is presently one of the most controversial land management issues in Australia. Part of this controversy results from the potential impacts of forestry practices on forest-dependent fauna, particularly those that are rare and endangered, such as Leadbeater's Possum Gymnobelideus leadbeateri McCoy, in the forests of central Victoria, south-eastern Australia. A significant proportion of the highly limited distribution of this species overlaps with some of the most valuable wood production forests in Australia within which extensive clearfelling operations are employed to produce timber and pulpwood. These operations can destroy the habitat of G. leadbeateri. The Victoria government agency that is responsible for forest and wildlife management has devised a forest zoning system as part of the management strategies to conserve G. leadbeateri within timber production areas. This is designed to partition the forest into three types of areas: (1) where the conservation of G. leadbeateri is a priority, (2) where wood production is a priority, and, (3) where both land uses are a joint priority. The classification of areas of forest where the conservation of G. leadbeateri is the primary land use is based on an understanding of the habitat requirements of the species. The results of recent field studies, where statistical models of the habitat requirements of G. leadbeateri have been developed and their performance subsequently tested using a new dataset, highlights the need for a new basis to guide the classification of areas for the conservation of the species within wood production forests. We describe a method for devising a forest management zoning system that is based on a statistical model of the habitat requirements of G. leadbeateri and which will better integrate wood production and the conservation of the species. This procedure accounts for the uncertainty in the statistical model and, in turn, reduces the risk that areas where G. leadbeateri occurs are logged, whilst ensuring that other areas are not unnecessarily excluded from timber harvesting.  相似文献   

16.
滇池流域水环境综合管理技术支撑平台构建研究   总被引:2,自引:1,他引:1  
滇池流域水环境综合管理技术支撑平台以实现水环境数据信息化、支撑多元化、管理智能化为目标,集成水环境多元数据采集传输、融合共享及动态表征技术,突破高原湖泊流域多目标复杂环境综合管理决策控制技术,构建"数据中心-业务系统-信息发布"为主线的综合管理平台,其以水环境数据中心为支撑,以水环境信息系统与水环境专家决策支持系统为核心,以水环境信息发布系统为共享交换媒介,为流域管理提供监控预警、总量控制、预测预报、项目评估及应急决策等技术服务,有效支撑滇池流域水环境监控预警和综合管理。  相似文献   

17.
18.
Effects of Scale and Logging on Landscape Structure in a Forest Mosaic   总被引:2,自引:0,他引:2  
Landscape structure in a forest mosaic changes with spatial scale (i.e. spatial extent) and thresholds may occur where structure changes markedly. Forest management alters landscapestructure and may affect the intensity and location of thresholds. Our purpose was to examine landscape structure at different scales to determine thresholds where landscape structure changes markedly in managed forest mosaics of the Appalachian Mountains in the eastern United States. We also investigated how logging influences landscape structure and whether these management activities change threshold values. Using threshold and autocorrelation analyses, we found that thresholds in landscape indices exist at 400, 500, and 800 m intervals from the outer edge of management units in our studyregion. For landscape indices that consider all landcovercategories, such as dominance and contagion, landscape structureand thresholds did not change after logging occurred. Measurements for these overall landscape indices were stronglyinfluenced by midsuccessional deciduous forest, the most commonlandcover category in the landscape. When restricting analysesfor mean patch size and percent cover to individual forest types,thresholds for early-successional forests changed after logging. However, logging changed the landscape structure at small spatialscale, but did not alter the structure of the entire forestmosaic. Previous forest management may already have increasedthe heterogeneity of the landscape beyond the point whereadditional small cuts alter the overall structure of the forest. Because measurements for landscape indices yield very differentresults at different spatial scales, it is important first toidentify thresholds in order to determine the appropriate scalesfor landscape ecological studies. We found that threshold andautocorrelation analyses were simple but powerful tools for thedetection of appropriate scales in the managed forest mosaicunder study.  相似文献   

19.
Forest Ecosystem Classification (FEC) systems have been used in the past mainly for forest management decision-making. FEC systems can also serve an important role for decision-making in other disciplines, such as fire management for both wildfire suppression and prescribed burning operations. FEC systems can provide an important means of identifying potential fuels that may be present on a forest site. This fuel information, in combination with current fire weather conditions, as determined by the Canadian Forest Fire Weather Index (FWI) system, can assist fire managers in determining potential fire behaviour if ignition should occur. FEC systems provide a means of identifying the possible presence of a live understory vegetation component, a fuel layer that has been largely ignored in the past due to a lack of information. Dense understory vegetation can produce a very moist microlimate that can effectively hinder fire spread. The use of FEC systems can help in setting priorities on which wildfires need to be attacked aggressively. For prescribed burning, FEC systems can assist in achieving burn objectives better and more safely.  相似文献   

20.
Because natural ecosystems and ecosystem services (ES) are both critical to the well-being of humankind, it is important to understand their relationships and congruence for conservation planning. Spatial conservation planning is required to set focused preservation priorities and to assess future ecological implications. This study uses the combined measures of ES models and ES potential to estimate and analyze all four groups of ecosystem services to generate opportunities to maximize ecosystem services. Subsequently, we identify the key areas of conservation priorities as future forestation and conservation hotspot zones to improve the ecological management in Chongqing City, located in the upper reaches of the Three Gorges Reservoir Area, China. Results show that ecosystem services potential is extremely obvious. Compared to ecosystem services from 2000, we determined that soil conservation could be increased by 59.11%, carbon sequestration by 129.51%, water flow regulation by 83.42%, and water purification by 84.42%. According to our prioritization results, approximately 48% of area converted to forests exhibited high improvements in all ecosystem services (categorized as hotspot-1, hotspot-2, and hotspot-3). The hotspots identified in this study can be used as an excellent surrogate for evaluation ecological engineering benefits and can be effectively applied in improving ecological management planning.  相似文献   

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