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1.
Saproxylic (dead-wood-associated) and old-growth species are among the most threatened species in European forest ecosystems, as they are susceptible to intensive forest management. Identifying areas with particular relevant features of biodiversity is of prime concern when developing species conservation and habitat restoration strategies and in optimizing resource investments. We present an approach to identify regional conservation and restoration priorities even if knowledge on species distribution is weak, such as for saproxylic and old-growth species in Switzerland. Habitat suitability maps were modeled for an expert-based selection of 55 focal species, using an ecological niche factor analyses (ENFA). All the maps were then overlaid, in order to identify potential species’ hotspots for different species groups of the 55 focal species (e.g., birds, fungi, red-listed species). We found that hotspots for various species groups did not correspond. Our results indicate that an approach based on “richness hotspots” may fail to conserve specific species groups. We hence recommend defining a biodiversity conservation strategy prior to implementing conservation/restoration efforts in specific regions. The conservation priority setting of the five biogeographical regions in Switzerland, however, did not differ when different hotspot definitions were applied. This observation emphasizes that the chosen method is robust. Since the ENFA needs only presence data, this species prediction method seems to be useful for any situation where the species distribution is poorly known and/or absence data are lacking. In order to identify priorities for either conservation or restoration efforts, we recommend a method based on presence data only, because absence data may reflect factors unrelated to species presence.  相似文献   

2.
/ The coastal zone of the Indian Ocean is coming under increasing pressure from human activities. Australia may be one of the few countries in this region that can afford to take adequate conservation measures in the near future. As it also has one of the longest Indian Ocean coastlines, Australia has the opportunity, and responsibility, to make a meaningful contribution to the conservation of Indian Ocean biodiversity. Threatened species, including marine turtles, inshore dolphins, and dugongs are an important component of that biodiversity. The dugong has been exterminated from several areas in the Indian Ocean, and it appears to be particularly threatened by mesh netting andhunting. Its long-term survival may depend on adequate protection in Australia, which contains the largest known Indian Ocean populations. This protection will require, in part, an appropriate system of marine protected areas (MPAs). This paper examines the adequacy of MPAs along Australia's Indian Ocean coast. Dugongs occur in two MPAs in Western Australia. The proposed expansion of the system of marine reserves is based primarily on representative samples of ecosystems from each biogeographic region. It is inadequate because it does not take into account the distribution and relative abundance of threatened species. If the conservation of biodiversity is to be maximized, the system of MPAs should incorporate both representativeness and the needs of threatened species. The level of protection provided by MPAs in Western Australia is low. Under current government policy potentially damaging activities, including commercial fishing, seismic surveys, and oil and gas drilling are permitted in protected areas.KEY WORDS: Marine protected areas; Dugongs; Western Australia; Indian Ocean; Conservation; Biodiversity  相似文献   

3.
/ Whereas habitat conservation plans (HCPs) have been intended to provide comprehensive environmental mitigation for multiple species, they often narrow in focus to one species and either one mitigation site or unspecified sites. We developed an indicators framework from which to rate land units for their ecological integrity, collateral values (nonbiological qualities that can improve conservation), and restoration and conservation opportunities. The ratings of land units were guided by the tenets of conservation biology and principles of landscape and ecosystem ecology, and they were made using existing physical and floral information managed on a GIS. As an example of how the indicators approach can be used for HCPs, the 29 legally rare species targeted by the Yolo County HCP were each associated with vegetation complexes and agricultural crops, the maps of which were used for rating some of the landscape indices. The ratings were mapped so that mitigation can be directed to the places on the landscape where the legally rare species should benefit most from conservation practices. The most highly rated land units for conservation opportunity occurred along streams and sloughs, especially where they emerged from the foothills and entered the Central Valley and where the two largest creeks intersected the Sacramento River flood basin. We recommend that priority be given to mitigation or conservation at the most highly rated land units. The indices were easy to measure and can be used with other tools to monitor the mitigation success. The indicators framework can be applied to other large-area planning efforts with some modifications.KEY WORDS: Ecosystem; Indicators; Landscape; Mitigation; Planning; Yolo County; California  相似文献   

4.
The Mekong River Basin is considered to be the second most species rich river basin in the world. The 795,000 km(2) catchment encompasses several ecoregions, incorporating biodiverse and productive wetland systems. Eighty percent of the rapidly expanding population of the Lower Mekong Basin (LMB), made up in part by Lao PDR, Thailand, Cambodia and Viet Nam, live in rural areas and are heavily reliant on wetland resources. As the populations of Cambodia and Lao PDR will double in the next 20 years, pressure on natural resources and particularly wetlands can only increase. For development planning, resource and conservation management to incorporate wetland issues, information on the distribution and character of Mekong wetlands is essential. The existing but outdated wetland maps were compiled from secondary landuse-landcover data, have limited coverage, poor thematic accuracy and no meta-data. Therefore the Mekong River Commission (MRC) undertook to produce new wetland coverage for the LMB. As resources, funding and regional capacity are limited, it was determined that the method applied should use existing facilities, be easily adaptable, and replicable locally. For the product to be useful it must be accepted by local governments and decision makers. The results must be of acceptable accuracy (>75%) and the methodology should be relatively understandable to non-experts. In the first stage of this exercise, field survey was conducted at five pilot sites covering a range of typical wetland habitats (MRC wetland classification) to supply data for a supervised classification of Landsat ETM images from the existing MRC archive. Images were analysed using ERDAS IMAGINE and applying Maximum Likelihood Classification. Field data were reserved to apply formal accuracy assessment to the final wetland habitat maps, with resulting accuracy ranging from 77 to 94%. The maps produced are now in use at a Provincial and National level in three countries for resource and conservation planning and management applications, including designation of a Ramsar wetland site of international importance.  相似文献   

5.
Conventional biodiversity surveys play an important role in ensuring good conservation friendly management in tropical forest regions but are demanding in terms of expertise, time, and budget. Can local people help? Here, we illustrate how local knowledge can support low cost conservation surveys. We worked in the Malinau watershed, East Kalimantan, Indonesia, an area currently at risk of extensive forest loss. We selected eight species of regional conservation interest: rafflesia (Rafflesia spp.), black orchid (Coelogyne pandurata), sun bear (Helarctos malayanus), tarsier (Tarsius bancanus), slow loris (Nycticebus coucang), proboscis monkey (Nasalis larvatus), clouded leopard (Neofelis diardi/N. nebulosa), and orang-utan (Pongo pygmaeus). We asked 52 informants in seven villages if, where and when they had observed these species. We used maps, based on both geo-referenced and sketched features, to record these observations. Verification concerns and related issues are discussed. Evaluations suggest our local information is reliable. Our study took 6 weeks and cost about USD 5000. Extensive expert based field surveys across the same region would cost one or two orders of magnitude more. The records extend the known distribution for sun bear, tarsier, slow loris, and clouded leopard. Reports of rafflesia, proboscis monkey, and orang-utan are of immediate conservation significance. While quality concerns should never be abandoned, we conclude that local people can help expand our knowledge of large areas in an effective, reliable, and low cost manner and thus contribute to improved management.  相似文献   

6.
Alternative energy development is increasing, potentially leading to negative impacts on wildlife populations already stressed by other factors. Resource managers require a scientifically based methodology to balance energy development and species conservation, so we investigated modeling habitat suitability using Maximum Entropy to develop maps that could be used with other information to help site energy developments. We selected one species of concern, the Lesser Prairie-Chicken (LPCH; Tympanuchus pallidicinctus) found on the southern Great Plains of North America, as our case study. LPCH populations have been declining and are potentially further impacted by energy development. We used LPCH lek locations in the state of Kansas along with several environmental and anthropogenic parameters to develop models that predict the probability of lek occurrence across the landscape. The models all performed well as indicated by the high test area under the curve (AUC) scores (all >0.9). The inclusion of anthropogenic parameters in models resulted in slightly better performance based on AUC values, indicating that anthropogenic features may impact LPCH lek habitat suitability. Given the positive model results, this methodology may provide additional guidance in designing future survey protocols, as well as siting of energy development in areas of marginal or unsuitable habitat for species of concern. This technique could help to standardize and quantify the impacts various developments have upon at-risk species.  相似文献   

7.
8.
The development of conservation strategies for nontimber forest products requires the characterization of the management systems and ethnoecological knowledge of the used species, as well as the analysis of the biological impacts of these processes. This study aimed to evaluate management systems and extractivist areas and related ethnoecological knowledge of Dimorphandra gardneriana (fava d’anta) in the semiarid region of Ceará, Northeast of Brazil. Fava d’anta produces fruits with high concentration of bioflavonoids, substances with various pharmacological properties, being exploited by extractivist communities in the mosaic of protected areas in Chapada do Araripe, Ceará. Ethnoecological knowledge has been concentrated on collectors who have been in activity for a longer time and/or plant the species. We identified three management systems that can impact in different ways on fava d’anta populations, depending on the area and level of human interference with the species. The extractivists respect the zoning of protected areas and do not enter in the full protection area, choosing areas with the highest tree density. The different systems produce a mosaic that creates different extraction opportunities and modifications to the local landscape and to fava d’anta populations. Factors that may have effects on the conservation of the species are the lack of supervision and overexploitation of the resource in native areas, while the factors that affect the health of extractivists are the infrastructure of the work and exposure to wild environments.  相似文献   

9.
Forest management can benefit from decision support tools, including GIS-based multicriteria decision-aiding approach. In the Mediterranean region, Pinus pinaster forests play a very important role in biodiversity conservation and offer many socioeconomic benefits. However, the conservation of this species is affected by the increase in forest fires and the expansion of Matsucoccus feytaudi. This paper proposes a methodology based on commonly available data for assessing the values and risks of P. pinaster forests and to generating maps to aid in decisions pertaining to fire and phytosanitary risk management. The criteria for assessing the values (land cover type, legislative tools for biodiversity conservation, environmental tourist sites and access routes, and timber yield) and the risks (fire and phytosanitation) of P. pinaster forests were obtained directly or by considering specific indicators, and they were subsequently aggregated by means of GIS-based multicriteria analysis. This approach was tested on the island of Corsica (France), and maps to aid in decisions pertaining to fire risk and phytosanitary risk (M. feytaudi) were obtained for P. pinaster forest management. Study results are used by the technical offices of the local administration—Corsican Agricultural and Rural Development Agency (ODARC)—for planning the conservation of P. pinaster forests with regard to fire prevention and safety and phytosanitary risks. The decision maker took part in the evaluation criteria study (weight, normalization, and classification of the values). Most suitable locations are given to target the public intervention. The methodology presented in this paper could be applied to other species and in other Mediterranean regions.  相似文献   

10.
Park managers in alpine areas must deal with the increase in forest coverage that has been observed in most European mountain areas, where traditional farming and agricultural practices have been abandoned. The aim of this study is to develop a fine-scale model of a broad area to support the managers of Paneveggio Nature Park (Italy) in conservation planning by focusing on the fate of priority areas for conservation in the next 50–100 years. GIS analyses were performed to assess the afforestation dynamic over time using two historical maps (from 1859 and 1936) and a series of aerial photographs and ortho-photos (taken from 1954 to 2006) covering a time span of 150 years. The results show an increase in the forest surface area of about 35%. Additionally, the forest became progressively more compact and less fragmented, with a consequent loss of ecotones and open habitats that are important for biodiversity. Markov chain-cellular automata models were used to project future changes, evaluating the effects on a habitat scale. Simulations show that some habitats defined as priority by the EU Habitat Directive will be compromised by the forest expansion by 2050 and suffer a consistent loss by 2100. This protocol, applied to other areas, can be used for designing long-term management measures with a focus on habitats where conservation status is at risk.  相似文献   

11.
Multiple-species reserves aim at supporting viable populations of selected species. Population viability analysis (PVA) is a group of methods for predicting such measures as extinction risk based on species-specific data. These methods include models that simulate the dynamics of a population or a metapopulation. A PVA model for the California gnatcatcher in Orange County was developed with landscape (GIS) data on the habitat characteristics and requirements and demographic data on population dynamics of the species. The potential applications of this model include sensitivity analysis that provides guidance for planning fieldwork, designing reserves, evaluating management options, and assessing human impact. The method can be extended to multiple species by combining habitat suitability maps for selected species with weights based on the threat faced by each species, and the contribution of habitat patches to the persistence of each species. These applications and extensions, together with the ability of the model to combine habitat and demographic data, make PVA a powerful tool for the design, conservation, and management of multiple species reserves.  相似文献   

12.
Croatia, like many other transition countries has undergone radical changes in its nature protection models. This paper discusses a historical overview, present situation and future possibilities for nature conservation in Croatia. A conservative top-down approach to nature protection was applied in the past in Croatia and is now being replaced by a prevalent bottom-up approach. Social context is crucial to introducing participatory conservation, therefore special concern is given to the perception of the local population towards protected area management in Istria as a case study in Croatia. Survey data were used to assess the conservation knowledge of local populations and their perception towards Protected Areas (PAs), leadership activities and management authorities in Istria County. This paper examines the perceptions of 313 residents living in and around six natural PAs located in Istria. The results revealed a moderate general knowledge about PAs in Istria and environmental issues, and a low awareness of institutions managing PAs, eagerness to participate in the activities of PAs and general support for the conservation cause. Understanding the perception of local residents enables the creation of feasible, long-term strategies for the implementation of participatory conservation. The research identifies the need for greater human, technical and financial efforts to strengthen the management capabilities of local agencies responsible for PAs. The process of participatory conservation optimization in Croatia is underway and world experiences must be observed in order to create a congruent, site-specific model with the best possible results.  相似文献   

13.
As human influences fragment native communities and ecosystems, remaining land must be better managed to conserve many elements of biodiversity. Much of this land is privately held, yet traditional private land-use management practices often further diminish biodiversity by promoting favored or edge-adapted species. Today, private land stewards are increasingly aware of and concerned about biodiversity, but little guidance exists for them to make land-use decisions incorporating principles and knowledge from conservation biology. Consequently, most management strategies are highly subjective. This article addresses that problem by introducing current conservation wisdom to management and use of private lands. The result is a model program for developing land management plans, with the goal of maintaining viable populations and natural distributions of native species and communities from a landscape perspective. The program establishes a protocol for classifying sites according to the importance of their species, communities, and other elements to global and regional biodiversity. These site classifications are based on the management objectives necessary to maintain important elements. Once managers classify a site, the program provides management standards, general stewardship principles, examples of land management strategies, and basic monitoring and evaluation procedures.  相似文献   

14.
In nature reserves and habitat conservation areas, monitoring is required to determine if reserves are meeting their goals for preserving species, ecological communities, and ecosystems. Increasingly, reserves are established to protect multiple species and communities, each with their own conservation goals and objectives. As resources are always inadequate to monitor all components, criteria must be applied to prioritize both species and communities for monitoring and management. While methods for prioritizing species based on endangerment or risk have been established, approaches to prioritizing ecological communities for monitoring are not well developed, despite a long-standing emphasis on communities as target elements in reserve design. We established guidelines based on four criteria derived from basic principles of conservation and landscape ecology--extent, representativeness, fragmentation, and endangerment--to prioritize communities in the San Diego Multiple Species Conservation Plan (MSCP). The MSCP was one of the first multiple-species habitat conservation areas established in California, USA, and it has a complex spatial configuration because of the patterns of surrounding land use, which are largely urbanized. In this case study, high priority communities for monitoring include coastal sage scrub (high endangerment, underrepresented within the reserve relative to the region, and moderately fragmented), freshwater wetlands, and coastal habitats (both have high fragmentation, moderate endangerment and representativeness, and low areal extent). This framework may be useful to other conservation planners and land managers for prioritizing the most significant and at-risk communities for monitoring.  相似文献   

15.
Human-induced global climate change presents a unique and difficult challenge to the conservation of biodiversity. Despite increasing attention on global climate change, few studies have assessed the projected impacts of sea-level rise to threatened and endangered species. Therefore, we estimated the impacts of rising sea levels on the endangered Lower Keys marsh rabbit (Sylvilagus palustris hefneri) across its geographic distribution under scenarios of current conditions, low (0.3-m), medium (0.6-m), and high (0.9-m) sea-level rise. We also investigated the impacts of allowing vegetation to migrate upslope and not allowing migration and of two land-use planning decisions (protection and abandonment of human-dominated areas). Not surprisingly, under all simulations we found a general trend of decreasing total potential LKMR habitat with increasing sea-level rise. Not allowing migration and protecting human-dominated areas both tended to decrease potential LKMR habitat compared with allowing migration and abandoning human-dominated areas. In conclusion, conservation strategies at multiple scales need to be implemented in order to reduce the impact of global climate change on biodiversity and endangered species. At the regional level, managers must consider land-use planning needs that take into account the needs of both humans and biodiversity. Finally, at the local scale those agencies that are in charge of endangered species conservation and ecosystem management need to rethink static approaches to conservation or else stand by and watch ecosystems degrade and species go extinct. This can be accomplished by bioclimatic reserve systems where climatically underrepresented areas are included in conservation planning along with the standard concerns of threat, opportunity, connectivity, and viability.  相似文献   

16.
Conservation planning is the process of locating and designing conservation areas to promote the persistence of biodiversity in situ. To do this, conservation areas must be able to mitigate at least some of the proximate threats to biodiversity. Information on threatening processes and the relative vulnerability of areas and natural features to these processes is therefore crucial for effective conservation planning. However, measuring and incorporating vulnerability into conservation planning have been problematic. We develop a conceptual framework of the role of vulnerability assessments in conservation planning and propose a definition of vulnerability that incorporates three dimensions: exposure, intensity, and impact. We review and categorize methods for assessing the vulnerability of areas and the features they contain and identify the relative strengths and weaknesses of each broad approach. Our review highlights the need for further development and evaluation of approaches to assess vulnerability and for comparisons of their relative effectiveness.  相似文献   

17.
Wildlife managers are challenged with the task of deciding whether a management measure is appropriate or not, and furthermore they have to convince others about the merits of their decision. Population decline of some hare species (genus Lepus) has resulted in their Red Listing and conservation measures are being undertaken. Release or restocking is a frequent measure in some countries, and thousands of hares are released annually, mainly for hunting purposes. These hares can be obtained by either intensive or extensive rearing or translocation of the wild animals. Each method entails difficulties and different survival rates in the wild. Survival rates in the wild are low for hares intensively reared in cages but are higher for hares reared extensively in enclosures and wild translocated hares. The benefits of the hare release practice are significantly lower than the action’s implementation cost. Hare releases have not increased significantly the wild hare population or the hunting harvest in areas where the practice has been applied. The risk of genetic and evolutionary degradation and pathogen transmission is possible in wild populations. The need for wise management of this practice is evident and the term ‘Permitted Transferring Units’ should be introduced to denote regions where hares should not be transferred for rearing and release.  相似文献   

18.
Information about the net benefits of land degradation treatment is required at the relevant management level, such as regional, local or site-specific, to assist decision makers in the allocation of funds to soil conservation. In this paper, estimates of regional opportunity costs of erosion and costs of treatment are used to derive benefit-cost ratios to assess the profitability of gully erosion treatment for localities in the wheat-sheep zone of New South Wales. These results are then used to develop site-specific models which predict benefit-cost ratios of treatment from land attributes including gully length, slope, soil type and land use. These predictive models form the basis of a rapid appraisal method to aid soil conservation decisions.  相似文献   

19.
Management of ecological reserve lands should rely on the best available science to achieve the goal of biodiversity conservation. “Adaptive Resource Management” is the current template to ensure that management decisions are reasoned and that decisions increase understanding of the system being managed. In systems with little human disturbance, certain management decisions are clear; steps to protect native species usually include the removal of invasive species. In highly modified systems, however, appropriate management steps to conserve biodiversity are not as readily evident. Managers must, more than ever, rely upon the development and testing of hypotheses to make rational management decisions. We present a case study of modern reserve management wherein beavers (Castor canadensis) were suspected of destroying habitat for endangered songbirds (least Bell’s vireo, Vireo bellii pusillus, and southwestern willow flycatcher, Empidonax traillii extimus) and for promoting the invasion of an exotic plant (tamarisk, Tamarix spp.) at an artificial reservoir in southern California. This case study documents the consequences of failing to follow the process of Adaptive Resource Management. Managers made decisions that were unsupported by the scientific literature, and actions taken were likely counterproductive. The opportunity to increase knowledge of the ecosystem was lost. Uninformed management decisions, essentially “management by assertion,” undermine the long-term prospects for biodiversity conservation.  相似文献   

20.
Wildlife conservation policy for endangered species restoration follows a six-phase process. Population viability analysis (PVA) can play a major contributing role in four of these. PVA, as discussed here, is a technique where extinction vulnerabilities of small populations are estimated using computer simulation modeling. The benefits and limitations of using PVA in wildlife decision and policy processes are reviewed based on our direct experience. PVA permits decision makers to set time frames for management, estimate the required magnitude of restoration efforts, identify quantitative targets for species recovery, and select, implement, monitor, and evaluate management strategies. PVA is of greatest value for rare species policy and management. However, a limitation of PVA simulation models is that they are constrained by the amount of biological data available, and such data are difficult to obtain from small populations that are at immediate risk of extinction. These problems may be overcome with improved models and more data. Our experience shows benefits of PVA far outweigh its limitations, and applications of the approach are most useful when integrated with decision analysis and completed within an adaptive management philosophy. PVAs have been carried out for 14 Victorian species and less used elsewhere in Australia. Management and recovery plans are developed from these PVAs. We recommend that PVA be used to guide research programs, develop conservation strategies, and inform decision and policy making for both endangered and nonendangered species because it can significantly improve many aspects of natural resource policy and management.  相似文献   

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