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1.
Marine protected areas (MPAs) are one tool that can be used in the comprehensive management of human activities in areas of the ocean. Although researchers have supported using MPAs as an ecosystem management tool, scientific research on MPAs in areas other than fisheries and fisheries management is limited. This paper presents a model for designing marine protected areas that protect important components of the ecosystem while minimizing economic impacts on local communities. This model combines conservation principles derived specifically for the marine environment with economic impact assessment. This integrated model allows for consideration of both fishery and non-fishery resources and activities such as shipping and recreational boating. An illustration of the model is presented that estimates the total economic impacts on Massachusetts' coastal counties of restricting fishing and shipping at certain sites in an area in the southern Gulf of Maine. The results suggest that the economic impacts on the region would differ according to the site in which shipping and fishing were restricted. Restricting activities in certain sites may have considerable impacts on local communities. The use of the model for evaluating and comparing potential MPA sites is illustrated through an evaluation of three different policy scenarios. The scenarios demonstrate how the model could be used to achieve different goals for managing resources in the region: protecting important components of the ecosystem, minimizing economic impacts on the local region, or a combination of the two.  相似文献   

2.
The United Kingdom, under the Large Combustion Plant Directive of the European Community, is committed to cutting sulphur dioxide (SO2) emissions by 60% of 1980 levels by the year 2003. In order to justify this action and to support new decisions on further emission reductions, policy makers require knowledge of the economic benefits of abatement. Benefit estimates for the recovery of freshwater fish populations present difficulties since the effect of reduced acid deposition on environmental processes is complex and because fishery records are often inadequate or absent. This paper predicts the economic benefits of acid rain abatement to the rod and line salmon fishery of Galloway, South West Scotland. It achieves this by linking output on long term changes in water chemistry and fish population status from MAGIC, a process based catchment model for acidification, with catch and market value data. Predicted increases in the market value of the fishery are presented and the role of the model in economic analysis of environmental policy discussed.  相似文献   

3.
Ecosystems in the western Mediterranean basin have undergone intense changes in land use throughout the centuries, resulting in areas with severe alterations. Today, most these areas have become sensitive to human activity, prone to profound changes in land-use configuration and ecosystem services. A consensus exists amongst stakeholders that ecosystem services must be preserved but managerial strategies that help to preserve them while ensuring sustainability are often inadequate. To provide a basis for measuring implications of land-use change on carbon sequestration services, changes in land use and associated carbon sequestration potential throughout the 20th century in a rural area at the foothills of the Sierra Nevada range (SE Spain) were explored. We found that forest systems replaced dryland farming and pastures from the middle of the century onwards as a result of agricultural abandonment and afforestation programs. The area has always acted as a carbon sink with sequestration rates ranging from 28,961 t CO2 year?1 in 1921 to 60,635 t CO2 year?1 in 1995, mirroring changes in land use. Conversion from pastures to woodland, for example, accounted for an increase in carbon sequestration above 30,000 t CO2 year?1 by the end of the century. However, intensive deforestation would imply a decrease of approximately 66% of the bulk CO2 fixed. In our study area, woodland conservation is essential to maintain the ecosystem services that underlie carbon sequestration. Our essay could inspire policymakers to better achieve goals of increasing carbon sequestration rates and sustainability within protected areas.  相似文献   

4.
The concept of ecosystem services is entering the agenda of land-use planning and scientists optimistically expect it to inform planners and decision-makers about the benefits that ecosystems provide. While tools and methods have been developed for mapping and valuing ecosystem services, only little attention has been paid to the practical application of the approach or its institutional preconditions and implications. We empirically analysed two urban planning processes for building residential areas in the outskirts of growing population centres in Finland. Our analysis of documents and interviews with planners focused on the benefits provided by ecosystems as well as the associated rights and responsibilities. We found that the concept ‘ecosystem service’ was not used, yet various benefits were identified. The rights of different stakeholders to ecosystem services were not explicitly identified, but many ecosystem services were perceived as public goods and particularly access to recreation was highlighted as an important justification for green areas. The results show that while the ecosystem services approach introduces new insights to land-use planning, it is still not embedded in the current practices or institutions. Operationalizing ecosystem services requires institutional adaptation, case-specific tailoring of methods, and deliberation among practitioners and stakeholders.  相似文献   

5.
Approximately 52% of the 380,000 tons of fish landings in Iran come from the northern Persian Gulf, with a total of 108,000 fishermen and 8900 fishing vessels (2003 data). The fishery in the region is very important for the local economy, but the major problems facing the Iranian fisheries are an uncertain availability of fish and over-fishing. The Persian Gulf is a sensitive marine ecosystem. The Gulf is a partially enclosed sea with an average depth of 35 metres and replacement of waters take some three to five years. Environmental factors have a major effect on fish stocks and fisheries in such a sensitive ecosystem. This study examines the influence of environmental changes in water temperature, rainfall, wind and sea level pressure on fish stocks in the northern Persian Gulf and estimates the maximum sustainable yields for fisheries management. Multivariate data and surplus production bio-economic models with environmental parameters are used to determine optimal harvest and forecasting. The study found that rainfall, water temperature and wind had significant positive effects whereas sea level pressure had a negative effect on the fisheries in the northern Persian Gulf. It is concluded that environmental parameters should be monitored concurrently with the fisheries to allow a greater understanding for fisheries management in the Persian Gulf.  相似文献   

6.
Fraser River sockeye salmon have been the basis for a major commercial fishery shared by Canada and the United States, and an important cultural foundation for many aboriginal groups; they are also of huge ecological significance throughout the Fraser Basin. The potential for altered aquatic habitat and temperature regimes due to climate change is an important concern for Fraser River sockeye salmon. This paper characterizes the vulnerability of Fraser River sockeye salmon to future climate change using an approach that is novel on three counts. First, previous efforts to assess the vulnerability of salmon to climate change have largely focused on only part of the life cycle, whereas we consider climate vulnerability at all stages in the life cycle. Second, we use the available scientific literature to provide a basis for structuring and eliciting judgments from fisheries science and management experts who research and manage these systems. Third, we consider prospects for mitigating the effects of climate change on sockeye salmon. Tests showed that participants’ judgments differentiated in statistically significant ways among questions that varied in terms of life stages, spawning regions and climate scenarios. The consensus among participants was that Fraser River sockeye are most vulnerable to climate change during the egg and returning adult stages of the life cycle. A high temperature scenario was seen as imposing the greatest risk on sockeye stocks, particularly those that migrate to the upper reaches of the Fraser River system and spawn earlier in the summer. The inability to alter water temperature and the highly constrained nature of sockeye management, with competing gear types and sequential fisheries over a long distance, suggest the potential to mitigate adverse effects is limited. Fraser River sockeye already demonstrate a great deal of adaptive capacity in utilizing heterogeneous habitats in different river sub-basins. This adaptability points to the potential value of policies to make stocks more resilient to uncertain futures.  相似文献   

7.
The Florida Bay ecosystem supports a number of economically important ecosystem services, including several recreational fisheries, which may be affected by changing salinity and temperature due to climate change. In this paper, we use a combination of physical models and habitat suitability index models to quantify the effects of potential climate change scenarios on a variety of juvenile fish and lobster species in Florida Bay. The climate scenarios include alterations in sea level, evaporation and precipitation rates, coastal runoff, and water temperature. We find that the changes in habitat suitability vary in both magnitude and direction across the scenarios and species, but are on average small. Only one of the seven species we investigate (Lagodon rhomboides, i.e., pinfish) sees a sizable decrease in optimal habitat under any of the scenarios. This suggests that the estuarine fauna of Florida Bay may not be as vulnerable to climate change as other components of the ecosystem, such as those in the marine/terrestrial ecotone. However, these models are relatively simplistic, looking only at single species effects of physical drivers without considering the many interspecific interactions that may play a key role in the adjustment of the ecosystem as a whole. More complex models that capture the mechanistic links between physics and biology, as well as the complex dynamics of the estuarine food web, may be necessary to further understand the potential effects of climate change on the Florida Bay ecosystem.  相似文献   

8.
Semi-arid Mediterranean regions are highly susceptible to desertification processes which can reduce the benefits that people obtain from healthy ecosystems and thus threaten human wellbeing. The European Union Biodiversity Strategy to 2020 recognizes the need to incorporate ecosystem services into land-use management, conservation, and restoration actions. The inclusion of ecosystem services into restoration actions and plans is an emerging area of research, and there are few documented approaches and guidelines on how to undertake such an exercise. This paper responds to this need, and we demonstrate an approach for identifying both key ecosystem services provisioning areas and the spatial relationship between ecological processes and services. A degraded semi-arid Mediterranean river basin in north east Spain was used as a case study area. We show that the quantification and mapping of services are the first step required for both optimizing and targeting of specific local areas for restoration. Additionally, we provide guidelines for restoration planning at a watershed scale; establishing priorities for improving the delivery of ecosystem services at this scale; and prioritizing the sub-watersheds for restoration based on their potential for delivering a combination of key ecosystem services for the entire basin.  相似文献   

9.
Linking GIS-based models to value ecosystem services in an Alpine region   总被引:12,自引:1,他引:11  
Planning frequently fails to include the valuation of public goods and services. This can have long-term negative economic consequences for a region. This is especially the case in mountainous regions such as the Alps, which depend on tourism and where land-use changes can negatively impact key ecosystem services and hence the economy. In this study, we develop a semi-automatic procedure to value ecosystem goods and services. Several existing process-based models linked to economic valuation methods are integrated into a geographic information system (GIS) platform. The model requires the input of a digital elevation model, a land-cover map, and a spatially explicit temperature dataset. These datasets are available for most regions in Europe. We illustrate the approach by valuing four ecosystem services: avalanche protection, timber production, scenic beauty, and habitat, which are supplied by the “Landschaft Davos”, an administrative district in the Swiss Alps. We compare the impacts of a human development scenario and a climate scenario on the value of these ecosystem services. Urban expansion and tourist infrastructure developments have a negative impact on scenic beauty and habitats. These impacts outweigh the benefits of the developments in the long-term. Forest expansion, predictable under a climate change scenario, favours natural avalanche protection and habitats. In general, such non-marketed benefits provided by the case-study region more than compensate for the costs of forest maintenance. Finally, we discuss the advantages and disadvantages of the approach. Despite its limitations, we show how this approach could well help decision-makers balance the impacts of different planning options on the economic accounting of a region, and guide them in selecting sustainable and economically feasible development strategies.  相似文献   

10.
The article presents the platform “Pimp your landscape” (PYL), which aims firstly at the support of planners by simulating alternative land-use scenarios and by an evaluation of benefits or risks for regionally important ecosystem services. Second, PYL supports an integration of information on environmental and landscape conditions into impact assessment. Third, PYL supports the integration of impacts of planning measures on ecosystem services. PYL is a modified 2-D cellular automaton with GIS features. The cells have the major attribute “land-use type” and can be supplemented with additional information, such as specifics regarding geology, topography and climate. The GIS features support the delineation of non-cellular infrastructural elements, such as roads or water bodies. An evaluation matrix represents the core element of the system. In this matrix, values in a relative scale from 0 (lowest value) to 100 (highest value) are assigned to the land-use types and infrastructural elements depending on their effect on ecosystem services. The option to configure rules for describing the impact of environmental attributes and proximity effects on cell values and land-use transition probabilities is of particular importance. User interface and usage of the platform are demonstrated by an application case. Constraints and limits of the recent version are discussed, including the need to consider in the evaluation, landscape-structure aspects such as patch size, fragmentation and spatial connectivity. Regarding the further development, it is planned to include the impact of land management practices to support climate change adaptation and mitigation strategies in regional planning.  相似文献   

11.
Land-use change is the main component of regional environmental change, while protected areas represent a direct land use policy to prevent its potentially negative effects on biodiversity and environmental services. We combined an analysis of trends in land use and human demography with trends in creation of protected areas during the last three decades in northwestern Argentina, a subtropical region including a wide range of environments. The eighty nine administrative analysis units of the region were classified into four ecological groups based on their percentage of cover by the six eco-regions of the study area: (1) "Dry valleys"; dominated by Middle-elevation deserts; (2) "Highlands", dominated by High-elevation alpine zones and plateaus; (3) "Humid ecosystems", dominated by Foggy grasslands and Humid forests, and (4) "Dry forests". Between 1970 and 2002, human population became concentrated in urban areas and land use trends varied greatly among the four ecological groups. Agricultural area decreased in the Highlands and increased in the other regions, particularly in the Dry forests. Domestic animals decreased in Humid ecosystems, Highlands and the Dry valleys; and remained constant in the Dry forests. Several protected areas were created, but most of them were established in regions undergoing a decreasing intensity of land use. Overall, the analysis shows that agricultural production is becoming concentrated in the areas more suitable for modern agriculture while marginal agriculture areas and, particularly, extensive grazing are decreasing. The creation of protected areas reflects the decreasing opportunity costs of marginal areas and is failing to protect the eco-regions most threatened by current land-use trends.  相似文献   

12.
Data needed for informed conservation prioritization are generally greater than the data available, and surrogates are often used. Although the need to anticipate threats is recognized, the effectiveness of surrogates for predicting habitat loss (or vulnerability) to land-use change is seldom tested. Here, we compared properties of two different vulnerability surrogates to validated vulnerability—validated prediction of habitat conversion based on a recent assessment of land-use change. We found that neither surrogate was a particularly effective predictor of vulnerability. Importantly, both surrogates performed poorly in places most imminently threatened with habitat conversion. We also show that the majority of areas protected over the last two decades have low vulnerability to the most active threatening process in this biome (habitat conversion). The contrary patterns of vulnerability and protection suggest that use of validated vulnerability would help to clarify protection needs, which might lead to the improvement of conservation decisions. Our study suggests the integration of validated vulnerability into conservation planning tools may be an important requirement for effective conservation planning in rapidly changing landscapes. We apply our results to discuss the practical considerations and potential value of incorporating validated vulnerability into conservation planning tools both generally and in the context of New Zealand’s indigenous grasslands.  相似文献   

13.
ABSTRACT: This study investigates the use of a two‐dimensional hydrodynamic model (River2D) for an assessment of the effects of instream large woody debris and rock groyne habitat structures. The bathymetry of a study reach (a side channel of the Chilliwack River located in southwestern British Columbia) was surveyed after the installation of 11 instream restoration structures. A digital elevation model was developed and used with a hydrodynamic model to predict local velocity, depth, scour, and habitat characteristics. The channel was resurveyed after the fall high‐flow season during which a bankfull event occurred. Pre‐flood and post‐flood bathymetry pool distributions were compared. Measured scour was compared to predicted shear and pre‐flood and post‐flood fish habitat indices for coho salmon (Oncorhynchus kisutch) and steelhead trout (O. mykiss) were compared. Two‐dimensional flow model velocity and depth predictions compare favorably to measured field values with mean standard errors of 24 percent and 6 percent, respectively, while areas of predicted high shear coincide with the newly formed pool locations. At high flows, the fish habitat index used (weighted usable area) increased by 150 percent to 210 percent. The application of the hydrodynamic model indicated a net habitat benefit from the restoration activities and provides a means of assessing and optimizing planned works.  相似文献   

14.
Natural resource management has traditionally been organized within discrete land, water, and fishery resource sectors. However, emerging environmental problems often cross these boundaries, and managers have struggled to find effective planning approaches for multi-resource concerns. No case better exemplifies these challenges than efforts to ensure sufficient flows of water for salmon in the Pacific Northwest. In this study, we investigate the organizational experiences of collaborative water and salmon recovery planning groups in the Puget Sound region of Washington. Using conceptual frameworks from organizational sociology, we examine how different regulative, normative, and cultural-cognitive institutional forces shape the structure and behavior of both water and salmon recovery planning groups. Data obtained through content analysis of planning documents and interviews with natural resource planners illustrate that legal structures, shared intra-group norms, and the distinct organizational cultures of water and salmon recovery groups constrain these organizations' ability to address linked water-for-salmon concerns. These findings illustrate that assessing institutional and organizational arrangements may be equally as important as understanding hydrology and biology when attempting to forward an integrated approach to water and fisheries management.  相似文献   

15.
ABSTRACT: The Umatilla River Basin Fisheries Restoration Plan was initiated in the early 1980s to mitigate salmonid losses caused by hydroelectric development and habitat degradation. The objectives are to enhance the abundance of endemic steelhead and reintroduce extirpated chinook and coho salmon. The project prompted collaborative effort among federal, state, and tribal agencies, and local water users. It has incorporated habitat restoration, flow enhancement, fish passage improvements, and population supplementation through artificial production. Water exchanges have successfully increased minimum flows during spring and fall migration. While flows remain depressed compared to historic conditions, there is potential for improved habitat, passage, and homing. The mean adult‐to‐adult return rate of hatchery‐reared steelhead exceeded replacement and that of the naturally‐spawning population. Although the smolt‐to‐adult survival rates of hatchery‐reared fish fluctuate, salmonid escapement has increased in recent years, permitting steelhead and spring chinook harvest. Enumeration of potential spawners and observed redds reveals an increase in natural production of all supplemented species. Comparison of hatchery‐reared and naturally‐spawning steelhead populations revealed differences in life history characteristics (in age composition and sex ratios) though run timing and genetic stock compositions of the two components of the populations have not differed. Sustained monitoring is needed to determine benefits of integrating habitat restoration and artificial production in restoring salmonid populations.  相似文献   

16.
Roadless and Low-Traffic Areas as Conservation Targets in Europe   总被引:1,自引:0,他引:1  
With increasing road encroachment, habitat fragmentation by transport infrastructures has been a serious threat for European biodiversity. Areas with no roads or little traffic (“roadless and low-traffic areas”) represent relatively undisturbed natural habitats and functioning ecosystems. They provide many benefits for biodiversity and human societies (e.g., landscape connectivity, barrier against pests and invasions, ecosystem services). Roadless and low-traffic areas, with a lower level of anthropogenic disturbances, are of special relevance in Europe because of their rarity and, in the context of climate change, because of their contribution to higher resilience and buffering capacity within landscape ecosystems. An analysis of European legal instruments illustrates that, although most laws aimed at protecting targets which are inherent to fragmentation, like connectivity, ecosystem processes or integrity, roadless areas are widely neglected as a legal target. A case study in Germany underlines this finding. Although the Natura 2000 network covers a significant proportion of the country (16%), Natura 2000 sites are highly fragmented and most low-traffic areas (75%) lie unprotected outside this network. This proportion is even higher for the old Federal States (western Germany), where only 20% of the low-traffic areas are protected. We propose that the few remaining roadless and low-traffic areas in Europe should be an important focus of conservation efforts; they should be urgently inventoried, included more explicitly in the law and accounted for in transport and urban planning. Considering them as complementary conservation targets would represent a concrete step towards the strengthening and adaptation of the Natura 2000 network to climate change.  相似文献   

17.
The Chinese government initiated a massive conservation program called “Grain-for-Green” in 1999 to reduce soil erosion and improve ecosystem function. Implementing practical sustainable development in the loess plateau still remains problematic, particularly in its eco-fragile areas. Here we discussed an approach for sustainable development at the watershed scale by integrating land use suitability, ecosystem services and public participation in the loess hilly area. We linked land use scenario analysis and economic modeling to compare the outcomes of three scenarios, CLU (Current Land Use), GOLU (Grain-production Oriented Land Use) and PSLU (Potential Sustainable Land Use). The results indicated that compared to PSLU, GOLU may provide a higher economic productivity in the short-term, but not in the long-term. CLU ranked lowest in terms of economic benefits and did not meet the daily needs of the local farmers. To reconcile the land use adjustments with farmers’ basic needs, a labor-saving land use strategy is necessary. Since the PSLU scenario assumes that slope cropland should be converted to pastures or orchards, more time may be available for off-farm work and for more public participation in integrated ecosystem management. Financial support to the local farmers for environmental conservation should be modulated in function of their positive contribution to ecosystem management.  相似文献   

18.
Preservation of small natural areas is not in itself a sufficient measure to maintain the integrity of the ecosystems for which they were initially set aside. Intense pressure from recreational use is just one of the many human-caused stresses that may degrade natural areas. Therefore, land-use planning and management from an ecological perspective is necessary to assess, ensure, and in some cases increase, the ecological integrity of protected natural areas. An ecosystem management approach for small protected natural areas with high recreational use is presented, based on three interrelated components: an ecological evaluation procedure of ecosystems, the implementation of management interventions on ecosystems, and the development of a monitoring scheme of ecosystem components. The ecological evaluation procedure combines two concepts: the biotic value of vegetation and wildlife and the abiotic fragility of the soils. This combined evaluation process results in the creation of a sensitivity map that can be used as a management tool for planners and managers. Management interventions, the second component of the management approach, are derived from concepts of ecological succession. Intentional human interventions are used to maintain the ecological integrity of ecosystems or in some cases to restore degraded sites. For the third component, only the basic principles of the monitoring program will be discussed. A pilot project in one of the Montreal urban community protected areas is presented to illustrate aspects of the proposed ecosystem management approach.  相似文献   

19.
Tropical fisheries, which are considered multi-species, may show selectiveness. We analyzed the degree of selectivity of fish catches in 46 sites along the Amazon basin through the percentage of biomass corresponding to the most caught fish species. Amazonian fisheries were considered moderately selective, as 54% of the sites directed more than a quarter of fishing effort to one fish species and in 87% of the sites more than half the fishing effort was directed to five fish species. Commercial fisheries were more selective than subsistence fisheries. Eleven fish species (nine of them migratory) have received more fishing pressure in the studied Amazonian regions and the catch composition differed among regions. We thus recommend that fisheries management in the Amazon basin should distribute fishing effort among more fish species; incorporate the particularities of commercial and subsistence fisheries; evaluate fishing effects on ecosystem services; and consider the biological characteristics of preferred fish.  相似文献   

20.
.Fish and wildlife enhancement through water resources development implies fish and wildlife will be enhanced or benefit directly from such development. As a matter of practicality, the opposite may be the case in that wildlife lands of prime value and stream fisheries are often lost or severely altered as a result of reservoir construction or stream channelization. Additionally, estuarine fish and wildlife can also suffer from water resources development due to reductions in volume of fresh waters reaching the estuaries and adjacent marshes. In some instances waterfowl habitat can be created by reservoir construction and with good planning waterfowl habitat and use may be enhanced. To offset losses of thousands of acres of wildlife habitat when a river system is to be totally harnessed, planners could set aside sufficiently large natural areas dedicated for use by wildlife. This, however, would be replacement rather than enhancement. Reservoir fisheries can be enhanced with good planning to include timber clearing, shoreline clearing, boat road clearing, variable level drawoff devices and tailrace escapement channels. To sum up, it is possible for some species offish and wildlife to be enhanced through water resources development but only at the expense of others, and then only through careful and integrated planning.  相似文献   

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