首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 15 毫秒
1.
Freshwater ecosystems are the most threatened ecosystems worldwide. Argentinian‐protected areas have been established mainly to protect vertebrates and plants in terrestrial ecosystems. In order to create a comprehensive biodiverse conservation plan, it is crucial to integrate both aquatic and terrestrial systems and to include macroinvertebrates. Here, we address this topic by proposing priority areas of conservation including invertebrates, aquatic ecosystems, and their connectivity and land uses. Location: Northwest of Argentina. We modeled the ecological niches of different taxa of macroinvertebrates such as Coleoptera, Ephemeroptera, Hemiptera, Megaloptera, Lepidoptera, Odonata, Plecoptera, Trichoptera, Acari, and Mollusca. Based on these models, we analyzed the contribution of currently established protected areas in the conservation of the aquatic biodiversity and we propose a spatial prioritization taking into account possible conflict regarding different land uses. Our analysis units were the real watersheds, to which were added longitudinal connectivity up and down the rivers. A total of 132 species were modeled in the priority area analyses. The analysis 1 showed that only an insignificant percentage of the macroinvertebrates distribution is within the protected areas in the North West of Argentina. The analyses 2 and 3 recovered similar values of protection for the macroinvertebrate species. The upper part of Bermejo, Salí‐Dulce, San Francisco, and the Upper part of Juramento basins were identified as priority areas of conservation. The aquatic ecosystems need special protection and 10% or even as much as 17% of land conservation is insufficient for species of macroinvertebrates. In turn the protected areas need to combine the aquatic and terrestrial systems and need to include macroinvertebrates as a key group to sustain the biodiversity. In many cases, the land uses are in conflict with the conservation of biodiversity; however, it is possible to apply the connectivity of the watersheds and create multiple‐use modules.  相似文献   

2.
Summary Australia is committed to protecting its important and representative ecosystems. Foremost among protection measures is the network of terrestrial and marine protected areas that comprise the National Reserve System (NRS). However, these reserves were often established with little regard for the conservation needs of riverine ecosystems. There has been no conservation status assessment to determine whether riverine ecosystems are adequately protected within terrestrial reserves. This study begins this task by determining the extent of riverine protection through the NRS. Three classes of protection are defined based on the proportion of the catchment of each stream segment (the link between tributary confluences) that is contained within a protected area, and the presence of major in‐stream barriers. The analysis reveals cause for concern. While nearly 225 000 km (7.6%) of the 2.9 million kilometres of streams assessed fall within a protected area of IUCN class I to IV where the principal objective is nature conservation, just 12 334 km of stream, less than half of one per cent of the total stream length, receives Class A protection, the strongest level of protection against threat. Class A is achieved where an entire drainage basin is contained within a protected area. Most of the protected stream length of the larger, named streams is potentially threatened by land‐use activities occurring in unprotected headwaters or is fragmented by major dams and thus receives the lowest class of protection. Owing to a variety of pervasive threats, a more comprehensive conservation status assessment of these ecosystems would undoubtedly yield an even more pessimistic result. Such an assessment is recommended.  相似文献   

3.
以海河流域为研究对象,依托系统保护规划的理论、方法和技术手段,建立气候-地貌-湿地生态地理综合分类单元,并将此单元作为宏观尺度湿地生物多样性的替代单元,同时以湿地水鸟作为物种尺度的指示物种,综合考虑道路、居民点等社会因素,确定了海河流域湿地保护优先格局及保护空缺。研究结果表明:湿地结构上,现有保护体系中仅滨海湿地受保护比例较高,经系统保护规划优后,湿地保护比例可达28.55%,保护面积达36.55 km2;在空间分布上,仅徒骇马颊河水系目前得到较好的保护,建议对滦河及冀东沿海区域及海河流域南北水系通过设立保护小区和建立湿地公园等方式加强保护。研究结果可为海河流域湿地保护体系调整提供参考,为湿地、非湿地生态系统的整合优化提供有益启示。  相似文献   

4.
黄河是中华文明的发源地, 被誉为母亲河, 是两岸社会经济发展的保障, 切实保护好黄河流域湿地生态系统, 事关中华民族伟大复兴的千秋大计。黄河流域湿地总面积为391万ha, 其中80.4%分布在上游, 中游和下游分别仅12.5%和7.1%。黄河流域是东亚-澳大利西亚候鸟迁徙路线和中亚候鸟迁徙路线上水鸟的关键栖息地, 一些迁徙水鸟最关键的栖息地均分布在黄河流域, 如黑颈鹤(Grus nigricollis)、白鹤(G. leucogeranus)、丹顶鹤(G. japonensis)、斑头雁(Anser indicus)、大鸨(Otis tarda)、东方白鹳(Ciconia boyciana)、大天鹅(Cygnus cygnus)、疣鼻天鹅(C. olor)、青头潜鸭(Aythya baeri)等。尽管黄河流域湿地提供的水资源仅占全国的2%, 但维持着全国12%的人口饮水安全和15%的耕地用水, 湿地生态系统的脆弱性较高。截至2017年底, 黄河流域已建立各类湿地自然保护地230处, 其中国家公园2处、国家级自然保护区9处、地方级自然保护区68处、国家湿地公园145处、省级湿地公园6处, 湿地保护率达到65%, 高于我国湿地保护53%的平均水平。然而, 流域尺度现有水鸟生物多样性保护仍然面临不少挑战, 包括全球气候变化、水资源过度利用、水环境污染、栖息地丧失等。为此, 我们提出了建立以国家公园为主体的湿地保护地体系、开展濒危候鸟栖息地修复和强化黄河流域综合管理的体制机制建设等建议。  相似文献   

5.
郭云  梁晨  李晓文 《生态学报》2018,38(6):1984-1993
基于系统保护规划的理论和方法,以长江流域湿地为研究区,构建了基于气候、地貌分异的湿地生态地理综合分类单元,并将其作为宏观尺度湿地生态系统保护目标,同时考虑以湿地鸟类为代表的物种保目标,依托Marxan系统保护规划工具,确定了长江流域湿地保护具有不可替代性的优先保护格局。该格局能以最小的社会经济和土地资源代价最大程度的保护湿地生物多样性,对比现有湿地保护格局,最终确定了游离于现有保护体系外的湿地保护空缺。研究结果表明:长江流域源区和长江三角洲地区的湿地保护体系完善,无需新建保护区;金沙江流域湿地保护空缺主要分布在现有保护区周围,可以适当扩充保护区外围或调整边界;嘉陵江流域和长江上游干流流域的保护空缺严重,大面积集中在重庆西北部,乌江流域的贵州省习水县北部湖泊湿地存在保护空缺,这些区域建议适当新建保护区或者保护小区;长江中下游湿地保护空缺主要分布在湖北、湖南、江西与安徽境内的沿江湖泊湿地,建议建立湿地公园及合理进行河流岸坡修复。研究结果可为长江流域湿地保护体系调整、保护规划制定提供参考依据,从宏观层面上为长江流域湿地统筹保护及合理开发利用提供科学依据。  相似文献   

6.
A method for spatial freshwater conservation prioritization   总被引:1,自引:0,他引:1  
1. Freshwater ecosystems are amongst the most threatened and poorly protected globally. They continue to be degraded through habitat loss, pollution and invading species and conservation measures are urgently needed to halt declining trends in their biodiversity and integrity.
2. During the past decade a suite of decision support tools and computational approaches have been developed for efficient and targeted conservation action in terrestrial or marine ecosystems. These methods may be poorly suited for planning in freshwater systems because connectivity in terrestrial and marine systems is typically modelled in a way unsuitable for rivers, where connectivity has a strong directional component.
3. We modify the conservation prioritization method and software, zonation , to account for connectivity in a manner better suited to freshwater ecosystems. Prioritization was performed using subcatchment/catchment-based planning units and connectivity was modified to have directional upstream and downstream components consistent with the ecology of our target species.
4. We demonstrate this modified method for rivers and streams in the southern North Island of New Zealand. Data included predicted occupancy from boosted regression tree models of species distributions for 18 fish species. The study area covered 2.1 million hectares and included 394 first- to fourth order catchment or subcatchment planning units.
5. Realistic modelling of connectivity had a major influence on the areas proposed for conservation. If connectivity was ignored, recommended conservation areas were very fragmented. By contrast, when connectivity was modelled, high priority conservation targets consisted of entire river basins or headwater subcatchments.
6. The proposed method serves as a starting point for the implementation of reserve selection methods in river ecosystems.  相似文献   

7.
The conservation and management of inland fish and freshwater ecosystems immensely contribute to global sustainable development. The existing ‘Protected Area’ (PA) network does not represent freshwater resources well and seldom considers its fish communities, while designating PAs. A study was undertaken to quantitatively assess the role played by the three terrestrial PAs (IUCN category IV) in conserving fish diversity and preserving habitat quality in the river reaches bordering the three PAs of the river Pranhita. It is a unique river system in the Indian Deccan Plateau in terms of fish diversity and community structure. Field surveys were conducted during the non-monsoon and monsoon seasons in 2020–21, that recorded 53 species including endemic and threatened fishes from river Pranhita, which represent more than one-third the number of fish species of Telangana state. The higher diversity and lower dominance index value (p < 0.01) reported in PAs compared to Eco Sensitive Zones and unprotected areas during the non-monsoon season indicate the role of intact physical habitat in providing refuges to the fish species in monsoon dependent tropical rivers. The optimal water quality revealed no significant difference (p > 0.0001) between protected and unprotected river reaches, and healthy biotic integrity assessed on the basis of fish community structure was attributed to the contiguous flow and less anthropogenic disturbance. This study supports that it can be considered as a representative zone for the conservation and protection of indigenous and endemic fish species of the Godavari Basin. The results concluded that the scope of the terrestrial PA network in India could be potentially extended to their bordering aquatic ecosystems, especially rivers to maintain pristine habitat conditions and conserve the fish genetic resources to ensure the flow of ecosystem services.  相似文献   

8.
Aim Recent efforts to apply the principles of systematic conservation planning to freshwater ecosystems have focused on the special connected nature of these systems as a way to ensure adequacy (long‐term maintenance of biodiversity). Connectivity is important in maintaining biodiversity and key ecological processes in freshwater environments and is of special relevance for conservation planning in these systems. However, freshwater conservation planning has focused on longitudinal connectivity requirements within riverine ecosystems, while other habitats, such as floodplain wetlands or lakes and connections among them, have been overlooked. Here, we address this gap by incorporating a new component of connectivity in addition to the traditional longitudinal measure. Location Northern Australia. Methods We integrate lateral connections between freshwater areas (e.g. lakes and wetlands) that are not directly connected by the river network and the longitudinal upstream–downstream connections. We demonstrate how this can be used to incorporate ecological requirements of some water‐dependent taxa that can move across drainage divides, such as waterbirds. Results When applied together, the different connectivity rules allow the identification of priority areas that contain whole lakes or wetlands, their closest neighbours whenever possible, and the upstream/downstream reaches of rivers that flow into or from them. This would facilitate longitudinal and lateral movements of biota while minimizing the influence of disturbances potentially received from upstream or downstream reaches. Main conclusions This new approach to defining and applying different connectivity rules can help improve the adequacy of freshwater‐protected areas by enhancing movements of biodiversity within priority areas. The integration of multiple connectivity needs can also serve as a bridge to integrate freshwater and terrestrial conservation planning.  相似文献   

9.
Brazil has a variety of aquatic ecosystems and rich freshwater biodiversity, but these components have been constantly damaged by the expansion of unsustainable activities. An array of different conservation strategies is needed, especially the creation of protected areas (PAs, hereafter). However, Brazil's PAs are biased towards terrestrial ecosystems and we argue that current PAs have limited efficacy in the protection of freshwater biodiversity. New PAs should better consider aquatic environments, covering entire basins, rivers and other freshwater habitats. We recommend ways to implement these PAs and provide guidance to avoid social impacts. Freshwater systems in Brazil provide essential goods and services but these ecosystems are being rapidly degraded and will be lost if not adequately protected.  相似文献   

10.
尤溪县生物多样性保护优先地区分析   总被引:9,自引:2,他引:7  
李迪强  林英华  陆军 《生态学报》2002,22(8):1315-1322
选择人类活动频繁的常绿阔叶林林区具有代表性的福建尤溪县进行了生物多样性保护的优先性分析。在多次实地调查基础上,利用野生动物野外实地样带调查数据,已有的珍稀淑危鸟,兽和植物物种的分布资料,同时结合利用地理信息系统软件ARC/INFO数字化1:10万林相图和1:5万地形图,建立了基于GIS的尤溪县生物多样性信息系统,然后根据物种多样性,珍稀濒危物种保护和生态系统保护目标,确立了保护优先性分析原则,即珍稀濒危物种尽可能包含在保护区和保护小区内,同时在优先保护区尽可能包含更多的其它物种,用最新的森林分布图及调查物种分布与生境关系,生态系统在保护物种与生态系统功能等方面的作用等,提出了生态系统的保护优先地区,将提出保护优先地区与已建保护小区和保护点分布图进行叠加分析表明,保护小区和保护点的方法是保护珍稀濒危物种的有效方法,但是需要考虑保护小区之间的联系,在对大型哺乳动物保护时需要建立面积较大的自然保护区,最后,提出了建立自然保护区规划。  相似文献   

11.
Hybridization between domestic and wild animals is a major concern for biodiversity conservation, and as habitats become increasingly fragmented, conserving biodiversity at all levels, including genetic, becomes increasingly important. Except for tropical forests and true deserts, African wildcats occur across the African continent; however, almost no work has been carried out to assess its genetic status and extent of hybridization with domestic cats. For example, in South Africa it has been argued that the long‐term viability of maintaining pure wildcat populations lies in large protected areas only, isolated from human populations. Two of the largest protected areas in Africa, the Kgalagadi Transfrontier and Kruger National Parks, as well as the size of South Africa and range of landscape uses, provide a model situation to assess how habitat fragmentation and heterogeneity influences the genetic purity of African wildcats. Using population genetic and home range data, we examined the genetic purity of African wildcats and their suspected hybrids across South Africa, including areas within and outside of protected areas. Overall, we found African wildcat populations to be genetically relatively pure, but instances of hybridization and a significant relationship between the genetic distinctiveness (purity) of wildcats and human population pressure were evident. The genetically purest African wildcats were found in the Kgalagadi Transfrontier Park, while samples from around Kruger National Park showed cause for concern, especially combined with the substantial human population density along the park's boundary. While African wildcat populations in South Africa generally appear to be genetically pure, with low levels of hybridization, our genetic data do suggest that protected areas may play an important role in maintaining genetic purity by reducing the likelihood of contact with domestic cats. We suggest that approaches such as corridors between protected areas are unlikely to remain effective for wildcat conservation, as the proximity to human settlements around these areas is projected to increase the wild/domestic animal interface. Thus, large, isolated protected areas will become increasingly important for wildcat conservation and efforts need to be made to prevent introduction of domestic cats into these areas.  相似文献   

12.
13.
1. Systematic conservation planning is a process widely used in terrestrial and marine environments. A principal goal is to establish a network of protected areas representing the full variety of species or ecosystems. We suggest considering three key attributes of a catchment when planning for aquatic conservation: irreplaceability, condition and vulnerability. 2. Based on observed and modelled distributions of 367 invertebrates in the Australian state of Victoria, conservation value was measured by calculating an irreplaceability coefficient for 1854 subcatchments. Irreplaceability indicates the likelihood of any subcatchment being needed to achieve conservation targets. We estimated it with a bootstrapped heuristic reserve design algorithm, which included upstream–downstream connectivity rules. The selection metric within the algorithm was total summed rarity, corrected for protected area. 3. Condition was estimated using a stressor gradient approach in which two classes of geographical information system Layers were summarised using principal components analysis. The first class was disturbance measures such as nutrient and sediment budgets, salinisation and weed cover. The second class was land use layers, including classes of forestry, agricultural and urban use. The main gradient, explaining 56% of the variation, could be characterised as agricultural disturbance. Seventy‐five per cent of the study area was classified as disturbed. 4. Our definition of vulnerability was the likelihood of a catchment being exposed to a land use that degrades its condition. This was estimated by comparing land capability and current land use. If land was capable of supporting a land use that would have a more degrading effect on a river than its current tenure, it was classified vulnerable (66% of the study area). 79% of catchments contained more then 50% vulnerable land. 5. When integrating the three measures, two major groups of catchments requiring urgent conservation measures were identified. Seven per cent of catchments were highly irreplaceable, highly vulnerable but in degraded condition. These catchments were flagged for restoration. While most highly irreplaceable catchments in good condition were already protected, 2.5% of catchments in this category are on vulnerable land. These are priority areas for assigning river reserves.  相似文献   

14.
Conservation practitioners face difficult choices in apportioning limited resources between rare species (to ensure their existence) and common species (to ensure their abundance and ecosystem contributions). We quantified the opportunity costs of conserving rare species of migratory fishes in the context of removing dams and retrofitting road culverts across 1,883 tributaries of the North American Great Lakes. Our optimization models show that maximizing total habitat gains across species can be very efficient in terms of benefits achieved per dollar spent, but disproportionately benefits common species. Conservation approaches that target rare species, or that ensure some benefits for every species (i.e., complementarity) enable strategic allocation of resources among species but reduce aggregate habitat gains. Thus, small habitat gains for the rarest species necessarily come at the expense of more than 20 times as much habitat for common ones. These opportunity costs are likely to occur in many ecosystems because range limits and conservation costs often vary widely among species. Given that common species worldwide are declining more rapidly than rare ones within major taxa, our findings provide incentive for triage among multiple worthy conservation targets.  相似文献   

15.
Limiting climate change to less than 2°C is the focus of international policy under the climate convention (UNFCCC), and is essential to preventing extinctions, a focus of the Convention on Biological Diversity (CBD). The post-2020 biodiversity framework drafted by the CBD proposes conserving 30% of both land and oceans by 2030. However, the combined impact on extinction risk of species from limiting climate change and increasing the extent of protected and conserved areas has not been assessed. Here we create conservation spatial plans to minimize extinction risk in the tropics using data on 289 219 species and modeling two future greenhouse gas concentration pathways (RCP2.6 and 8.5) while varying the extent of terrestrial protected land and conserved areas from <17% to 50%. We find that limiting climate change to 2°C and conserving 30% of terrestrial area could more than halve aggregate extinction risk compared with uncontrolled climate change and no increase in conserved area.  相似文献   

16.
In South Africa, the oribi, Ourebia ourebi is an endangered small antelope that requires conservation management and intervention to prevent their extinction. Use of translocation for the conservation of subpopulations facing local extinction in the wild has been proposed. In this study, fifteen oribi from threatened populations were captured and released (November 2004) on a private game reserve in KwaZulu-Natal, South Africa. Radio telemetry was used to monitor the dispersal and survival of translocated oribi. Only one death occurred during that period. All other released oribi survived, and most remained in close proximity of the release site for more than a year postrelease. Reproduction also occurred. This suggests that, translocation could be a viable option for conserving wild populations of oribi, assuming that other factors, such as availability of suitable grassland habitat and that poaching has been curtailed, are met.  相似文献   

17.

Aim

Comprehensive biodiversity protection necessitates the consideration of multiple indexes of diversity, and how the distribution patterns of priority areas may shift under climate change. Galliformes is a globally endangered avian order vulnerable to climate change that provide an important indicator for wildlife conservation effectiveness. Here, we identified priority areas for conserving Galliformes taxonomic, phylogenetic, and functional diversity in China and their spatial dynamics subject to climate change, and examined how well existing protected areas align with current and future priority areas.

Location

China.

Methods

We applied species distribution modelling and Zonation algorithms to identify conservation priority area dynamics for 47 galliform species across three biodiversity indexes subject to three future climate change scenarios to 2050s and 2070s. We overlaid these identified priority areas onto existing national nature reserves and national parks to assess and project their effectiveness.

Results

Current priority areas proved spatially incongruent between indexes, with an optimal area overlap comprising just 10.3% of China's land area, lying largely outside of existing protected areas. Furthermore, over 80% of modelled optimal priority areas currently lacked formal conservation status. Future priority areas will shift substantially under climate change, to an extent dependent on greenhouse gas emission scenarios. Nevertheless, we identified five large regions where optimal Galliformes diversity indexes should remain stable under all scenarios, thus providing potential climatic refugia, if protected from human encroachment.

Main Conclusions

The current deficits we identified for Galliformes protection in China resonate with a broader need for hierarchical conservation strategic planning across regions and ecosystems to ensure long-term biodiversity protection, accommodating for climate change.  相似文献   

18.
China harbors a high species diversity of freshwater fishes not shared with any of its neighboring nations. Freshwater fish diversity in the country has been under severe threat from human activities over the past decades, thus conservation freshwater fishes and ecosystems is urgently needed. To accumulate baseline data for guiding protection actions, the third red list assessment of Chinese freshwater fishes was carried out. Among Chinese freshwater fishes assessed, there are 355 at-risk species (22.3% of the total), including 69 ranked as Critically Endangered, 97 as Endangered, and 189 as Vulnerable. Two species are classified as Extinct and one as Regionally Extinct. China's threat level seems to be lower than the known average level found in the IUCN's global assessment of freshwater fishes, but this is an artifact of a high rate of species classified as Data Deficient. Conservation of freshwater fishes is presently facing a grim situation in China. Imperilment of Chinese freshwater fishes is primarily attributed to habitat loss and degradation arising from human perturbations, particularly river damming. Despite the adoption of protected areas setting up, captive breeding and release, and a fishing moratorium, conservation efforts for freshwater fishes are compromised by disproportional attention in China's biodiversity conservation, baseline data deficiency, insufficiently designed protection networks, and inefficient or inadequate implementation of conservation strategies. To achieve the objectives of Chinese freshwater fish conservation, it is proposed to conduct a national-scale survey of fish diversity and reassess their at-risk status, develop systematic conservation planning of freshwater fish diversity and ecosystems, prioritize strategies for protected areas development, perform genetic-based captive breeding for releasing in concert with other protection actions, and implement flexible fishing moratorium strategies in different water bodies.  相似文献   

19.
Rates of biodiversity loss are higher in freshwater ecosystems than in most terrestrial or marine ecosystems, making freshwater conservation a priority. However, prioritization methods are impeded by insufficient knowledge on the distribution and conservation status of freshwater taxa, particularly invertebrates. We evaluated the extinction risk of the world''s 590 freshwater crayfish species using the IUCN Categories and Criteria and found 32% of all species are threatened with extinction. The level of extinction risk differed between families, with proportionally more threatened species in the Parastacidae and Astacidae than in the Cambaridae. Four described species were Extinct and 21% were assessed as Data Deficient. There was geographical variation in the dominant threats affecting the main centres of crayfish diversity. The majority of threatened US and Mexican species face threats associated with urban development, pollution, damming and water management. Conversely, the majority of Australian threatened species are affected by climate change, harvesting, agriculture and invasive species. Only a small proportion of crayfish are found within the boundaries of protected areas, suggesting that alternative means of long-term protection will be required. Our study highlights many of the significant challenges yet to come for freshwater biodiversity unless conservation planning shifts from a reactive to proactive approach.  相似文献   

20.
Pelagic ecosystems support a significant and vital component of the ocean's productivity and biodiversity. They are also heavily exploited and, as a result, are the focus of numerous spatial planning initiatives. Over the past decade, there has been increasing enthusiasm for protected areas as a tool for pelagic conservation, however, few have been implemented. Here we demonstrate an approach to plan protected areas that address the physical and biological dynamics typical of the pelagic realm. Specifically, we provide an example of an approach to planning protected areas that integrates pelagic and benthic conservation in the southern Benguela and Agulhas Bank ecosystems off South Africa. Our aim was to represent species of importance to fisheries and species of conservation concern within protected areas. In addition to representation, we ensured that protected areas were designed to consider pelagic dynamics, characterized from time-series data on key oceanographic processes, together with data on the abundance of small pelagic fishes. We found that, to have the highest likelihood of reaching conservation targets, protected area selection should be based on time-specific data rather than data averaged across time. More generally, we argue that innovative methods are needed to conserve ephemeral and dynamic pelagic biodiversity.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号