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1.
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   

2.

Forests provide ecosystem services, including timber production. In some cases, private forest owners perform management actions in order to enhance the provision of such services, or they may be encouraged by public policies and payments. This paper focuses specifically on the decision to set forest land aside for biodiversity conservation, as part of the more general question of the efficiency of multiple-use vs. specialised management of forest lands. We propose an econometric analysis to identify factors in the set-aside choice and measure the impact of this decision on forest management costs. The results show that the set-aside choice depends on the landowners’ income and motivations related to forest amenities. The choice of specialised management, as reflected in the set-aside decision, has a significant and positive impact on the intensity of management in the remainder of the forest and on management costs. From a policy implications point of view, these results suggest that instruments such as forest certification, subsidies and reverse auctions for conservation will be most likely to attract the interest of those forest owners with personal motivations and forest properties that offer both benefit and cost advantages in opting for such specialised management strategies.

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3.
According to the International Decade for Natural Disaster Reduction (IDNDR 1990–1999), the risk indicates potential losses due to particular natural phenomenon, and these could be reduced by improving of prevention and education. People perceive these losses differently depending on phenomenon occurrence, severity, and impact in time. Starting from this idea, this research presents public perception on land degradation through erosion in a small area from the central part of Romania (south-west of Transylvanian Depression). The research was based on a questionnaire consisting of 16 questions. The items were structured by issues: awareness assessment regarding hazard and risk phenomena, assessment of type of property and land use, assessment of knowledge and information on the possible production of negative effects by natural phenomena, and evaluation of land owners’ attitudes towards the occurrence of erosion on their land. Results reveal that the public perception on erosion is weak. This process is perceived as insignificant due to lack of phenomenon knowledge and especially because of scarcity preoccupation in land’s quality monitoring. Even though the owned lands are affected by erosion forms, the owners are not aware of the phenomenon that generates them. Material damages caused by erosion, loss of soil quality, and land fertility decrease are less perceived because the economic losses fill only at long term. This perception leads to underestimating erosion risk compared to other natural phenomena and to a passive attitude towards this particular phenomenon.  相似文献   

4.
Many countries undertake a national forest inventory to enable statistically valid monitoring in support of national and international reporting of forest conditions and change. Canada’s National Forest Inventory (NFI) program is designed to operate on a 10-year remeasurement cycle, with an interim report produced at the 5-year mid-point. The NFI is a sample-based inventory, with approximately 18,850 2 ×2-km photo plots across the country, distributed on a 20×20-km grid of sample points; these photo plots are the primary data source for the NFI. Capacity to provide annual monitoring information is required to keep policy and decision makers apprised of current forest conditions. In this study, we implemented a multistage monitoring framework and used a Moderate Resolution Imaging Spectroradiometer (MODIS) change product to successfully identify 78% of the changes in forest cover area that were captured with a Landsat change detection approach. Of the NFI photo plots that were identified by both the Landsat and MODIS approaches as having changes in forest cover, the proportion of change area within the plots was similar (R 2?=?0.78). Approximately 70% of the Landsat-derived change events occupied less than 40% of a single MODIS pixel, and more than 90% of the change events of this size were successfully detected with the MODIS product. Finally, MODIS estimates of the proportion of forest cover change at the NFI photo plot level were comparable to change estimates for the ecoregions as a whole (R 2?=?0.95). High-temporal, low-spatial resolution imagery such as MODIS, in combination with other remotely sensed data sources, can provide information on disturbance events within a national forest inventory remeasurement cycle, thereby satisfying the interim information needs of policy and decision makers as well as the requirements of national and international reporting commitments.  相似文献   

5.
We propose a stochastic dynamic programming framework to model the management of a multi-stand forest under climate risk (strong wind occurrence). The preferences of the forest-owner are specified by a non-expected utility in order to separately analyze intertemporal substitution and risk aversion effects. A numerical method is developed to characterize the optimal forest management policies and the optimal consumption-saving strategy. The stochastic dynamic programming framework is applied to a non-industrial private forest-owner located in North-East of France. We show that the optimal decisions both depend upon risk and time preferences. The authors would like to thank participants at the international conference on Economics of Sustainable Forest Management in Toronto, at the PARIS 1 seminar on Environmental and Natural Resource Economics, at the 2004 Applied Microeconomics Conference in Lille and at the 13th annual conference of the European Association of Environmental and Resource Economists at Budapest.  相似文献   

6.
The purpose of this paper is to study the impacts of the vagueness about the transfer of the harvest right on the use of a natural resource. We develop one-period non-cooperative game frameworks to examine whether the choice of the resource owner to be hazy about the transmission of the harvest contract is optimal. In the perfect information situation, we show that it is optimal for the resource owner to forbid the transfer of the harvest right instead of being hazy about it when the transfer fees are lesser than the collected net punishment fines of the monitoring costs even though the resource would be inefficiently used. In particular, we find in this case that the government’s announcement to forbid the transfer of the right should be public. We further show that there are subgame Nash equilibria in the perfect information context and a unique Nash equilibrium in the imperfect information setting. Specifically, we show that, when the transfer fees are greater or equal to the (net) punishment fines, there is a Nash equilibrium both in perfect and imperfect information situations, precisely when the owner chooses to allow the transfer of harvest title and the resource harvester transfers it.  相似文献   

7.
In many European mountain regions, natural forest regrowth on abandoned agricultural land and the related consequences for the environment are issues of increasing concern. We developed a spatial statistical model based on multiple geophysical and socio-economic variables to investigate the pattern of natural forest regrowth in the Swiss mountain area between the 1980s and 1990s. Results show that forest regrowth occurred primarily in areas with low temperature sum, intermediate steepness and soil stoniness as well as close to forest edges and relatively close to roads. Model results suggest that regions with weak labor markets are favored in terms of land abandonment and forest regrowth. We could not find an effect of population change on land abandonment and forest regrowth. Therefore, we conclude that decision makers should consider non-linearities in the pattern of forest regrowth and the fact that labor markets have an effect on land abandonment and forest regrowth when designing measures to prevent agricultural land abandonment and natural forest regrowth in the Swiss mountains.  相似文献   

8.
Uncertainty is definitely one of the key topics in environmental assessment and management. Typically, attempts to reduce uncertainty are subject to expenses. But how to compare and trade-off expenses and the reduced uncertainty? They only seldom allow the use of a single unit. Instead, the whole analysis and decision procedure is very subjective. This paper presents one approach to handle such problems, namely the combined use of Bayesian influence diagrams, and probabilistic risk attitude analysis. The approach was used in the evaluation of three alternatives for a real time river water quality forecasting system. A trade-off analysis of risk attitudes, costs and uncertainty indicated the levels of socioeconomic utility required for investments in the respective systems, and accordingly illuminated the impact of the uncertainties involved on inference and decision-making with various risk attitudes and discount rates.  相似文献   

9.
Characterizing the forest fragmentation of Canada’s national parks   总被引:1,自引:0,他引:1  
Characterizing the amount and configuration of forests can provide insights into habitat quality, biodiversity, and land use. The establishment of protected areas can be a mechanism for maintaining large, contiguous areas of forests, and the loss and fragmentation of forest habitat is a potential threat to Canada’s national park system. Using the Earth Observation for Sustainable Development of Forests (EOSD) land cover product (EOSD LC 2000), we characterize the circa 2000 forest patterns in 26 of Canada’s national parks and compare these to forest patterns in the ecological units surrounding these parks, referred to as the greater park ecosystem (GPE). Five landscape pattern metrics were analyzed: number of forest patches, mean forest patch size (hectare), standard deviation of forest patch size (hectare), mean forest patch perimeter-to-area ratio (meters per hectare), and edge density of forest patches (meters per hectare). An assumption is often made that forests within park boundaries are less fragmented than the surrounding GPE, as indicated by fewer forest patches, a larger mean forest patch size, less variability in forest patch size, a lower perimeter-to-area ratio, and lower forest edge density. Of the 26 national parks we analyzed, 58% had significantly fewer patches, 46% had a significantly larger mean forest patch size (23% were not significantly different), and 46% had a significantly smaller standard deviation of forest patch size (31% were not significantly different), relative to their GPEs. For forest patch perimeter-to-area ratio and forest edge density, equal proportions of parks had values that were significantly larger or smaller than their respective GPEs and no clear trend emerged. In summary, all the national parks we analyzed, with the exception of the Georgian Bay Islands, were found to be significantly different from their corresponding GPE for at least one of the five metrics assessed, and 50% of the 26 parks were significantly different from their respective GPEs for all of the metrics assessed. The EOSD LC 2000 provides a heretofore unavailable dataset for characterizing broad trends in forest fragmentation in Canada’s national parks and in their surrounding GPEs. The interpretation of forest fragmentation metrics must be guided by the underlying land cover context, as many forested ecosystems in Canada are naturally fragmented due to wetlands and topography. Furthermore, interpretation must also consider the management context, as some parks are designed to preserve fragmented habitats. An analysis of forest pattern such as that described herein provides a baseline, from which changes in fragmentation patterns over time could be monitored, enabled by earth observation data.  相似文献   

10.
Investments in power generation constitute a typical budget allocation problem in the context of multiple objectives, while all factors influencing investor’s decisions for power plants are subject to considerable uncertainties. The paper introduces a multi-objective stochastic model designed to optimize budget allocation decisions for power generation in the context of risk aversion taking into account several sources of uncertainty, especially with regard to volatility of fossil fuel and electricity prices, technological costs, and climate policy variability. Probability distributions for uncertain factors influencing investment decisions are directly derived from the stochastic global energy model PROMETHEUS and thus they take into account complex interactions between variables in the systemic context. In order to fully incorporate stochastic characteristics of the problem, the model is specified as an optimization problem in which the probability that an objective exceeds a given threshold is maximized (risk aversion) subject to a set of deterministic and probabilistic constraints. The model is formulated as a mixed integer program providing complete flexibility on the joint distributions of rates of return of technologies competing for investments, as it can handle non-symmetric distributions and take automatically into account complex covariance patterns as emerging from comprehensive PROMETHEUS stochastic results. The analysis shows that risk is a crucial factor for power generation investments with investors not opting for technologies subject to uncertainty related to climate policies and fossil fuel prices. On the other hand, combination of options with negative covariance tends to benefit in the context of risk-hedging behavior.  相似文献   

11.
Fire risk evaluation using multicriteria analysis—a case study   总被引:2,自引:0,他引:2  
Forest fires are one of the major causes of ecological disturbance and environmental concerns in tropical deciduous forests of south India. In this study, we use fuzzy set theory integrated with decision-making algorithm in a Geographic Information Systems (GIS) framework to map forest fire risk. Fuzzy set theory implements classes or groupings of data with boundaries that are not sharply defined (i.e., fuzzy) and consists of a rule base, membership functions, and an inference procedure. We used satellite remote sensing datasets in conjunction with topographic, vegetation, climate, and socioeconomic datasets to infer the causative factors of fires. Spatial-level data on these biophysical and socioeconomic parameters have been aggregated at the district level and have been organized in a GIS framework. A participatory multicriteria decision-making approach involving Analytical Hierarchy Process has been designed to arrive at a decision matrix that identified the important causative factors of fires. These expert judgments were then integrated using spatial fuzzy decision-making algorithm to map the forest fire risk. Results from this study were quite useful in identifying potential “hotspots” of fire risk, where forest fire protection measures can be taken in advance. Further, this study also demonstrates the potential of multicriteria analysis integrated with GIS as an effective tool in assessing “where and when” forest fires will most likely occur.  相似文献   

12.
Analysis of the risks of sea-level rise favours conventionally measured metrics such as the area of land that may be subsumed, the numbers of properties at risk, and the capital values of assets at risk. Despite this, it is clear that there exist many less material but no less important values at risk from sea-level rise. This paper re-theorises these multifarious social values at risk from sea-level rise, by explaining their diverse nature, and grounding them in the everyday practices of people living in coastal places. It is informed by a review and analysis of research on social values from within the fields of social impact assessment, human geography, psychology, decision analysis, and climate change adaptation. From this we propose that it is the ‘lived values’ of coastal places that are most at risk from sea-level rise. We then offer a framework that groups these lived values into five types: those that are physiological in nature, and those that relate to issues of security, belonging, esteem, and self-actualisation. This framework of lived values at risk from sea-level rise can guide empirical research investigating the social impacts of sea-level rise, as well as the impacts of actions to adapt to sea-level rise. It also offers a basis for identifying the distribution of related social outcomes across populations exposed to sea-level rise or sea-level rise policies.  相似文献   

13.
Sustainable urban development requires the integration of environmental interests in urban planning. Although various methods of environmental assessment have been developed, plan outcomes are often disappointing due to the complex nature of decision-making in urban planning, which takes place in multiple arenas within multiple policy networks involving diverse stakeholders. We argue that the concept of ‘decision windows’ can structure this seemingly chaotic chain of interrelated decisions. First, explicitly considering the dynamics of the decision-making process, we further conceptualized decision windows as moments in an intricate web of substantively connected deliberative processes where issues are reframed within a decision-making arena, and interests may be linked within and across arenas. Adopting this perspective in two case studies, we then explored how decision windows arise, which factors determine their effectiveness and how their occurrence can be influenced so as to arrive at more sustainable solutions. We conclude that the integration of environmental interests in urban planning is highly dependent on the ability of the professionals involved to recognize and manipulate decision windows. Finally, we explore how decision windows may be opened.  相似文献   

14.
China’s Grain-For-Green Policy (GFGP) of returning marginal cropland to forest or grassland is one of the most important large-scale initiatives to combat land degradation in its ecologically vulnerable regions. In order to maintain and increase crop production from decreasing areas of cropland, substantial spatio-temporal changes in agrochemical inputs have occurred, which have strongly influenced the ecological and environmental status of land in China. Based on the agrochemical inputs (chemical fertilizer, pesticide, plastic sheeting, and agricultural diesel oil) at the provincial level between 1993 and 2009, cluster analysis and gravity center modeling were used to trace these spatio-temporal changes. A regional comparative study was also undertaken to investigate the changes in the relative size of agrochemical inputs in the eastern, central, and western regions of China. It was found that the agrochemical inputs increased considerably at the nation level after the GFGP, which in order of increasing rate were: plastic sheeting > agricultural diesel oil > pesticide > chemical fertilizer. The gravity centers of agrochemical inputs moved substantially towards the northwest or west during the latter period of GFGP and regional comparative analysis showed that the agrochemical inputs increased substantially in the western region between 2004 and 2009. The ecological degradation caused by the expansion of the area devoted to crop production in the western region and the potential risk of agricultural non-point pollution caused by the increasing agrochemical inputs are the main factors restricting this area’s sustainable development.  相似文献   

15.
Despite the importance of forested wetland in the global carbon cycle, no widely applicable ecosystem model exists for this ecosystem. This study reports the linkage between Wetland-DNDC and MIKE SHE for carbon dynamics and GHGs mitigation strategies analyses in forested wetland. Wetland-DNDC was modified by parameterizing forest management practices and refining anaerobic biogeochemical processes. Mortality due to senescence was estimated as a function of tree age or as a function of the relative biomass. We used a harvesting damage mortality coefficient as a linear function of time with three parameters: Initial mortality, Duration of the damage and Intensity of the initial harvesting. The model was validated against experimental data obtained from the GNF site near Florida. As a preliminary application, we simulated the effect of water table position and forest management practices on GHGs emissions and carbon dynamics to test the capabilities of the models for simulating seasonal and long-term carbon budget in forested wetland.  相似文献   

16.
A primer for nonresponse in the US forest inventory and analysis program   总被引:1,自引:0,他引:1  
Nonresponse caused by denied access and hazardous conditions are a concern for the USDA Forest Service, Forest Inventory and Analysis (FIA) program, whose mission is to quantify status and trends in forest resources across the USA. Any appreciable amount of nonresponse can cause bias in FIA’s estimates of population parameters. This paper will quantify the magnitude of nonresponse and describe the mechanisms that result in nonresponse, describe and qualitatively evaluate FIA’s assumptions regarding nonresponse, provide a recommendation concerning plot replacement strategies, and identify appropriate strategies to pursue that minimize bias. The nonresponse rates ranged from 0% to 21% and differed by land owner group; with denied access to private land the leading cause of nonresponse. Current FIA estimators assume that nonresponse occurs at random. Although in most cases this assumption appears tenable, a qualitative assessment indicates a few situations where the assumption is not tenable. In the short-term, we recommend that FIA use stratification schemes that make the missing at random assumption tenable. We recommend the examination of alternative estimation techniques that use appropriate weighting and auxiliary information to mitigate the effects of nonresponse. We recommend the replacement of nonresponse sample locations not be used.  相似文献   

17.
Environmental assessment (EA) aims to enhance environmental awareness and to ensure that environmental values are fully considered in decision-making. In the EA arena, different discourses exist on what EA should aim for and how it functions. We hypothesise that these discourses influence its application in practice as well as its effectiveness in terms of achieving the above goals. For instance, actors who consider EA as a hindrance to fast implementation of their projects will probably apply it as a mandatory checklist, whereas actors who believe that EA can help to develop more environmentally sound decisions will use EIA as a tool to design their initiatives. In this paper we explore discourses on EA in The Netherlands and elaborate on their implications for EA effectiveness. Based on an innovative research design comprising an online survey with 443 respondents and 20 supplementary semi-structured interviews we conclude that the dominant discourse is that EA is mainly a legal requirement; EAs are conducted because they have to be conducted, not because actors choose to do so. EA effectiveness however seems reasonably high, as a majority of respondents perceive that it enhances environmental awareness and contributes to environmental protection. However, the ‘legal requirement’ discourse also results in decision-makers seldom going beyond what is prescribed by EA and environmental law. Despite its mandatory character, the predominant attitude towards EA is quite positive. For most respondents, EA is instrumental in providing transparency of decision-making and in minimising the legal risks of not complying with environmental laws. Differences in discourses seldom reflect extreme opposites. The ‘common ground’ regarding EA provides a good basis for working with EA in terms of meeting legal requirements but at the same time does not stimulate creativity in decision-making or optimisation of environmental values. In countries characterised by less consensual political cultures we may expect more extreme discourses on EA, the consequences of which are reflected upon in this paper.  相似文献   

18.
Assessment of underwater noise is increasingly required by regulators of development projects in marine and freshwater habitats, and noise pollution can be a constraining factor in the consenting process. Noise levels arising from the proposed activity are modelled and the potential impact on species of interest within the affected area is then evaluated. Although there is considerable uncertainty in the relationship between noise levels and impacts on aquatic species, the science underlying noise modelling is well understood. Nevertheless, many environmental impact assessments (EIAs) do not reflect best practice, and stakeholders and decision makers in the EIA process are often unfamiliar with the concepts and terminology that are integral to interpreting noise exposure predictions. In this paper, we review the process of underwater noise modelling and explore the factors affecting predictions of noise exposure. Finally, we illustrate the consequences of errors and uncertainties in noise modelling, and discuss future research needs to reduce uncertainty in noise assessments.  相似文献   

19.
This paper examines the spread and development of ‘environmental impact assessment’ (EIA) since the enactment of the U.S. Environmental Policy Act on January 1, 1970, which established for the first time under any jurisdiction the formal requirement that an EIA be made and that an ‘environmental impact statement’ (EIS) be filed prior to implementation of certain major development projects. The paper is divided into three parts. In the first part, we briefly review the forms of EIA introduced in the western industrial countries and contrast these with developments in the socialist countries of Eastern Europe, and in the Third World. The approaches to EIA adopted by five countries — the United States, Australia, Canada, the Federal Republic of Germany, and the Soviet Union — are used to illustrate the types of national approaches that have been followed. In the second part of the paper, we use some questions raised by impact assessments as codified in legislation or regulations at the national level to highlight some of the limitations of impact assessment. Finally, we turn to international impact assessments and describe the modest progress made to date. Key impediments to the development of appropriate conceptual and institutional frameworks and methodologies for international EIAs are noted. In conclusion, we offer some suggestions about needed actions at both the national and international levels.  相似文献   

20.
While the development of maritime economic activity is increasingly encouraged, the consideration of its impacts constitutes a real challenge. The limitations of the implementation of the mitigation hierarchy have been widely discussed in scientific literature, yet data on marine biodiversity offset practices remains scarce. In this study, we investigated the use of Environmental Impact Assessments (EIAs) as suitable instruments to achieve the No Net Loss objective. Drawing on a French approach developed for the initial assessment of the European Marine Strategy Framework Directive, we examined the pressures and impacts related to various marine development projects and the effectiveness of the mitigation hierarchy in limiting these. An analysis of 55 recent French environmental impact studies showed that only 7% of the proposed measures had the aim of offsetting predicted degradation of sites of remarkable biodiversity. This can be partly explained by the lack of a clear definition of ‘significant impact’, which varies greatly depending on what is impacted, in turn allowing socio-economic activities to benefit more easily from offset. Furthermore, offsetting does not always constitute the final step of the mitigation hierarchy, highlighting the need to reinforce avoidance and reduction steps. Although we acknowledge the role of EIA in mitigating the negative impacts of development projects, synergies with other European marine environmental policies such as the Marine Strategy Framework Directive (MSFD) and the Maritime Spatial Planning directive (MSP) should be developed in order to improve current practices.  相似文献   

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