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1.
Due to the current environmental crisis, many animal species face extinction problems. Amphibian populations have been affected by this crisis. Our goal is to study amphibian species diversity in Chiapas, which has 7.6% of the endemic amphibians in Mexico and 53 protected areas. Only 58% of the protected areas have management plans or information on their resident amphibians. We aim to determine the extent of protection provided by the network of natural areas for the conservation of amphibian species in the state and to discuss the effectiveness of this protection. Therefore, we compiled a georeferenced database of 112 amphibian species in Chiapas to create each distribution model. In addition, we carried out representativeness, beta diversity, and species richness analyses. As a result, we obtained a high degree of representativeness for the records and species distribution models. However, we found a decrease in the richness of amphibians involving 20% of total species, 13% of endemics, 18% threatened according to NOM-059, and 31% threatened according to IUCN between 1800 and 2020 and 1980–2020. We also identified two biodiversity hotspots in the Sierra Madre de Chiapas and the Northern Highlands physiographic regions. Finally, based on potential distributions, we found more endemic and threatened species outside protected natural areas than inside them. Our results give a broader picture of how amphibian richness is distributed in Chiapas. This information can help to prioritize conservation efforts toward those areas rich in threatened or endemic species, such as the Northern Mountains Hotspot we identified in northern Chiapas.  相似文献   

2.
As an introduction to the Special Issue on the restoration of threatened plant species and their habitats,this editorial shows how the various papers in the issue address the range of in situ interventions involved in species population management and restoration of their habitat, together with examples of case studies implementing these actions. It stresses the need for integrating these various interventions.It highlights the importance of protected areas in providing a degree of protection for threatened species but also the need to complement this with actions at the species level to ensure the effective conservation and long term persistence of these species. It emphasizes that ecological restoration is a complement to, not a substitute for conservation, and that the balance of effort and allocation of resources between them is a key issue.  相似文献   

3.
In the past years, efforts have been made to include connectivity metrics in conservation planning in order to promote and enhance well-connected systems of protected areas. Connectivity is particularly important for species that rely on more than one realm during their daily or life cycle (multi-realm species). However, conservation plans for the protection of multi-realm species usually involve a single realm, excluding other realms from the prioritization process. Here, we demonstrate an example of cross-realm conservation planning application for the island of Cyprus by taking into account the terrestrial and marine realms and their interface (i.e. coast). Operating within a data-poor context, we use functional connectivity metrics to identify priority areas for the conservation of six multi-realm species, by setting conservation targets simultaneously for the terrestrial and marine realms. MARXAN decision-support tool was used for the identification of the priority areas.Four scenarios were developed to evaluate the impacts of including connectivity in the prioritization process and the effectiveness of the existing coastal/marine protected areas in the achievement of the conservation targets set for the species. All scenarios considered land and sea anthropogenic uses as surrogate costs to influence the prioritization process.Our findings show an increase in the area of the reserve network and, therefore, the cost, when connectivity is included, whilst reducing the total boundary length. Furthermore, the current reserve network fails to achieve conservation targets, particularly for the marine part, which has a substantially smaller protection coverage than the terrestrial part.We conclude that focus should be given in the expansion of the current coastal/marine reserve network following a cross-realm conservation approach. This approach is not only relevant for the conservation of multi-realm species, but also for islandscapes, in particular, where the interdependence between the hinterland and the coast is larger and therefore the magnitude of the impacts generated in one realm and affects the other.  相似文献   

4.
The conservation of biodiversity in Europe is defined by Directive 92/43/EEC – commonly known as the Habitats Directive – relating to the conservation of natural habitats and of wild flora and fauna. This Directive established the creation of an ecological network of European protected areas – the Natura 2000 network – , and also recognised the need to manage these areas to maintain their “favourable conservation status”.This paper proposes a methodology which enables the conservation of biodiversity to be integrated into the management of Natura 2000 forest spaces. The methodology comprises an “environmental diagnosis” in three phases. The first phase evaluates the current conservation status of habitats using the following criteria: vital functions; floristic richness; forest structure; area occupied by the habitat; and recovery capacity. The second phase assesses the fragility of the space to determine the degree of vulnerability of habitats. This involves evaluating the fire hazard, erosion hazard, and the fragility of the vegetation. The last phase combines the two previous ones to generate management areas (optimum, intermediate or unfavourable) and to prioritise management actions.This methodology was applied in a protected forest area in the Natura 2000 network, located in Avila (Spain). Different management areas were generated for biodiversity conservation, and each habitat was associated to one of them. Finally, actions were prioritised and designed to raise the habitats to a “favourable conservation status”.  相似文献   

5.
In the face of accelerating biodiversity loss it is more important than ever to identify important areas of biodiversity and target limited resources for conservation. We developed a method to identify areas of important plant diversity using known species’ distributions and evaluations of the species importance. We collated distribution records of vascular plants and developed a scoring method of spatial prioritisation to assign conservation value to the island of Ireland at the hectad scale (10 km × 10 km) and at the tetrad scale (2 km × 2 km) for two counties where sufficient data were available. Each plant species was assigned a species conservation value based on both its conservation status and distribution in Ireland. For each cell, the species conservation values within the cell were summed, thereby differentiating between areas of high and low conservation value across the landscape. Areas with high conservation value represent the most important areas for plant conservation.The protected area cover and the number of species present in these important areas were also examined by first defining threshold values using two different criteria. Species representation was high in the important areas; the identified important areas of plant diversity maintained high representation of species of conservation concern and achieved high species representation overall, requiring a low number of sites (<8%) to do so. The coincidence of protected areas and important areas for plant diversity was found to be low and while some important areas of plant diversity might benefit from the general protection afforded by these areas, our research highlights the need for conservation outside of protected areas.  相似文献   

6.
Wild pigs, including wild boar (Sus scrofa) and feral domestic pig (Sus scrofa domestica), are associated with negative impacts in their native and introduced ranges. We compiled wild pig occurrence reports and utilized Maximum Entropy modelling to predict their potential distribution in ecoregions overlaying Argentina, Brazil, Bolivia, Chile, Uruguay and Paraguay. An analysis of their observed and potential distributions was carried out in relation to four biodiversity hotspots and 3766 protected areas to estimate the number of units and percent area currently and potentially invaded. Among biodiversity hotspots, Atlantic Forest, Cerrado, and Chilean Winter Rainfall-Valdivian Forests included 44.7% of wild pig records. The proportion of suitable area was 85% in Atlantic Forest, 61.3% in Cerrado, 37.5% in Chilean Winter Rainfall-Valdivian Forests, and 5.6% in Tropical Andes. The number of protected areas with known wild pig presence was led by Uruguay (100%), followed by Chile (20.3%), Argentina (15.8%), Paraguay (9.5%), Bolivia (6.5%), and Brazil (4.7%). The proportion of protected areas with predicted wild pig presence was highest in Uruguay (100%), followed by Paraguay (72.6%), Brazil (58.0%), Argentina (57.4%), Chile (42.2%), and Bolivia (35.9%). Our work represents the first assessment of wild pig potential distribution in South America and highlights the potentially devastating impacts of wild pigs on the regional biodiversity and national conservation targets, especially at mega-diverse areas. We present a dynamic web application that can be readily consulted by scientists, managers and decision makers to improve wild pig control and risk mitigation actions in the study region.  相似文献   

7.
Seasonal and spatial patterns of light availability were investigated in the understory of a small fragment (approximately 1300 m2) of a riparian deciduous forest of the Kokai River in central Japan dominated byQuercus acutissima Carruth., with the aim to understand the characteristics of microsite light availability forArisaema heterophyllum Blume, a threatened plant species uniquely associated with the riparian habitat. Diffuse site factor, which is the ratio of PFD (photon flux density, 400–700 nm) at a microsite to the open sky reference under diffuse light condition, was shown to be a satisfactory index for the evaluation of light availability for the understory plants in the habitat. Diffuse site factor 1,0 1,000 understory microsites along a 20 m transect from the edge to the interior of the forest, showed conspicuous seasonal changes in both mean and variation. Light availability decreased with seasonal tree canopy regeneration, with the highest spatial heterogeneity being recorded during the time of canopy closure. Auto-correlations of microsite light availability between different seasons were considerably high, suggesting the stability of relative light availability for individual microsites throughout the growing season ofA. heterophyllum. Fairly high light availability during summer season, which surpassed 20% of the open sky reference in most microsites, would be important for the growth and persistence of summer herbaceous plants likeA. heterophyllum.  相似文献   

8.
With only five protected areas dedicated to the conservation of biodiversity (two national parks, one strict nature reserve and two faunal reserves), Guinea has one of the smallest protected area networks in West Africa. As a result, two of the five ecoregions of the country and six of the 14 globally threatened large and medium-sized mammals occurring in Guinea are not found in the national protected area network. To identify areas with high biodiversity that could be included in the national protected area network, we used the Key Biodiversity Areas (KBA) methodology. We devised a scoring system to rank the identified KBAs according to their relative conservation significance. We identified a total of 16 KBAs throughout the country. Their proclamation as protected areas would result in the protection of all ecoregions and all but one of Guinea’s globally threatened large and medium-sized mammals. Twelve of the 16 KBAs have the legal status of classified forest, a status that should facilitate the change into formal biodiversity protected areas (IUCN category I–IV). Our analysis indicates that even if only the two areas with the highest conservation significance score, the Ziama and Diécké forests, become formal protected areas, this would provide protection to both the western Guinean lowland forests, one of the most threatened ecoregions in Africa, and to 11 of the 14 threatened large and medium-sized mammals occurring in Guinea.  相似文献   

9.
10.
泡桐属(Paulownia)花粉,均为近球形,具3(拟)孔沟,外壁外层有清楚的异胞网状雕纹,沟界极区明显。这些共同特征,说明泡桐属是一个种间亲缘极近的自然的属;其萌发孔类型,可作为泡桐属归入玄参科的证据之一。通过花粉形态的比较,对兰考泡桐、宜昌泡桐和建始泡桐的分类地位,提出了论证。  相似文献   

11.
In order to understand the particular challenges that medicinal plant conservation and management raise at the global level, it is necessary to address issues pertaining their distribution and the environments where they grow. When reviewing medicinal plant studies from eight countries in four regions we found that a high proportion of the reported medicinal plants had wide distributions across countries and continents. Most plants are found wild (40.5%) or naturalized (33.9%), while only 3.3% are cultivated. Since many species are distributed in wild conditions, cultivated and naturalized in several continents, conservation and management interventions would be best served through collaboration between host countries.  相似文献   

12.
Different methodologies try to identify priority conservation areas (PCA) to improve habitat conservation and decrease human pressures over bird species at coarse-scale. Map of potential biodiversity (PB) can identify PCA (high PB values) at different scale levels by considering ecological requirements and distributions through potential habitat suitability (PHS) models. The aim was to elaborate a map of PB of bird species based on PHS models to spatially identify PCA in Santa Cruz, Argentina. Moreover, we want to analysis species’ ecology requirements, and evaluate PB values and spatially identify PCA through two scale levels. We computed 47 models using Environmental Niche Factor Analysis (ENFA) on Biomapper software. Each model was visualized and combined to get a unique map of PB. We analyzed ecological requirements by specialization and marginality and PHS maps. Moreover, considering natural environments (regional level) and forest types’ cover (forest landscape level), we evaluated PB values using ANOVAs and identified PCA under different human pressures, using human footprint (HPF) map. Bird species related to Nothofagus forests were most specialist and exhibited a narrower potential distribution than grassland species. At regional level, Magellanic grass steppes displayed the highest PB values, where most of the PCA had high HPF values. At forest landscape level, ecotone N. antarctica forests had the highest PB values, where PCA with low HFP values were outside current protected networking. We conclude that combining PHS models and the map of PB allowed us to improve bird distribution studies and to assist biodiversity conservation strategies under human pressures.  相似文献   

13.
In all member countries of the European Community, the influence of European directives is increasing. This is especially the case with directives on the conservation of natural habitats and wild fauna and flora (European Council Directive 92/43 EEC from 1992 (Council of the European Union 1992) and the directive on the conservation of wild birds (European Council directive 79/409 EEC from 1979 (Council of the European Union 1979). These directives are expected to influence the future development of nature-based sport and outdoor recreation significantly. Many German sport organisations are expecting negative consequences for the future development of nature-based sport in mountain areas. This paper summarises key findings of a study commissioned by the German Sport Association.

This project develops guidelines for the application and interpretation of these directives, as well as for their practicable use and management. The study shows that the potential negative effects of nature-based sport and outdoor recreation activities can be categorised into three general types. Furthermore, large sport events should be evaluated separately in the future. Finally, the crucial role of management plans is discussed, which are essential if NATURA 2000 areas are to be established successfully. The management plan assists in the selection of suitable measures, helps to resolve conflicts, and increases the level of acceptance and its transparency for the public. This paper will demonstrate that the consultation and participation of local people including members of sport and recreational organisations is essential to achieve the best result in the interest of nature conservation in general and conservation of endangered habitats or species specifically.  相似文献   


14.
The conservation policy of banning pastoral grazing, and subsequently emerging conflicts between conservationists and pastoral communities regarding the proliferation of Himalayan knotweed (Polygonum polystachyum), was studied in the Valley of Flowers National Park, a high altitude protected area of the Western Himalaya, India. A total of 10 habitat types identified in the study area were sampled using quadrats along an altitudinal gradient between 3000 and 4500 m. Plant species richness decreases with altitude and also varies across habitat types. The highest density of P. polystachyum and its associated species, Impatiens sulcata, was found between 3300 and 3500 m in the disturbed habitat types, viz., bouldery areas, fragmented treeline zone, avalanche-prone areas and eroded slopes. Eradication of P. polystachyum from the national park by managers is not going to serve any meaningful purpose to the long-term conservation; rather it initiates soil erosion and instability, hindering the establishment of natural plant communities.  相似文献   

15.
The Chalkhill Blue Polyommatus coridon is a widespread butterfly of lowland calcareous grassland in southern Britain and is considered a good indicator of habitat condition. Polyommatus coridon has been identified as a Species of Conservation Concern in the UK Biodiversity Action Plan due to a greater than 25% decline in range size since the 1950s, with losses due to the combined effects of habitat destruction, agricultural intensification and neglect. Analysis of annual butterfly monitoring data (transects) collected at 161 sites from 1981 to 2000 show a three-fold population recovery had occurred. The increases were at established sites, with no re-colonisations or range expansion detected. The 1980s population increase coincided with increases across the species range in stock and rabbit Oryctolagus cuniculus grazing, as well as greater protection and management of sites through protected areas and nature reserves. During the 1990s agri-environment schemes were thought to be the main conservation and policy mechanism driving the favourable conservation status of P. coridon, by facilitating appropriate habitat restoration and management. Weather played a part in the species recovery, with warm, but wet summers associated with increases in abundance. The research provides strong evidence of an important conservation success with the UK Biodiversity Action Plan, with implications for other specialist biodiversity.  相似文献   

16.
根据在吉林省蚊河实验管理局1hm^2落叶阔叶混交林样地调查结果,对落叶阔叶混交林的群落结构、物种多样性、主要树种的空间分布格局以及树木种群的种间关联进行了研究.结果表明,树木种群优势程度不明显;乔木、灌木、草本的均匀度指数、生态优势度指数都较低.对5个主要乔木种群的空间格局均呈现聚集分布;15个主要树种之间有14个种对存在着显著的种间关联,一个种独立;树种之间正关联的种对少,关联强度低,而负关联多且较高,群落结构组成不稳定,处于软阔叶林向硬阔叶林直至红松阔叶林过渡的阶段.  相似文献   

17.
根据在吉林省蛟河实验管理局1 hm2落叶阔叶混交林样地调查结果,对落叶阔叶混交林的群落结构、物种多样性、主要树种的空间分布格局以及树木种群的种间关联进行了研究.结果表明,树木种群优势程度不明显;乔木、灌木、草本的均匀度指数、生态优势度指数都较低.对5个主要乔木种群的空间格局均呈现聚集分布;15个主要树种之间有14个种对存在着显著的种间关联,一个种独立;树种之间正关联的种对少,关联强度低,而负关联多且较高,群落结构组成不稳定,处于软阔叶林向硬阔叶林直至红松阔叶林过渡的阶段.  相似文献   

18.
Summary

An overview on distribution, ecological preferences, threat status and bioacoustics of the keeled plump bush-cricket (Isophya costata) in northern Serbia is provided. Mowing in May and June and use of pesticides in agricultural landscapes close to habitats where I. costata occurs represent the main threats to long-term survival of this species at investigated localities. Based upon the present knowledge, this species in Serbia can be qualified as Endangered (EN) at the national level.  相似文献   

19.
Of the eight Cantharellus species known from Benin, seven have been encountered under similar macroecological conditions. The present work attempts to generate a more complete distribution of these seven species. Forty-eight occurrences of the target species and four explanatory variables including three bioclimatic variables and a land cover variable were used to build an ensemble model from five modelling approaches under the Biomod2 package of R software. Results showed a distribution restricted to the Bassila and Atacora mountain range phytogeographic districts with excellent statistical performance (TSS = 0.98, AUC = 0.99). This distribution is governed mainly by high soil moisture and high potential evapotranspiration, thus defining only gallery forests as the most suitable habitat for chanterelles in Sudano-guinean and Soudanese ecozones of Benin. Based on IUCN criterion B1 and sub-criteria B1a and B1c(i), these seven species were categorized under the Endangered (EN) threat category according to our results.  相似文献   

20.
China is among the world's richest countries in terms of plant biodiversity. Besides the abundant flora, containing some 33,000 vascular plants (30,000 angiosperms, 250 gymnosperms, and 2600 pteridophytes), there is extraordinary ecosystem diversity, as well as a large pool of both wild and cultivated germplasms. China is also considered one of the main centers of origin and diversification for seed plants on Earth, and is especially profuse in phylogenetically primitive taxa and/or paleoendemics due to the refuge role glaciation played during the Quaternary period. The collision with the Indian subcontinent significantly enriched Chinese flora and led to the formation of many neoendemisms. However, flora distribution remains uneven, and some local floristic hotspots are found across China, such as Yunnan, Sichuan and Taiwan. Unfortunately, this biodiversity faces enormous threats, which have increased substantially over the last 50 years. The combined effects of habitat destruction and/or fragmentation, environmental contamination, over-exploitation of natural resources, and to a lesser extent, introduction of exotic species, have caused irreparable damage to China's plant biodiversity. Burgeoning economic and population growth have also contributed to this deterioration. It is believed that up to 5000 flora species are currently endangered in China, with some taxa having already become extinct. Although in recent years government authorities have made some efforts to preserve biodiversity, much work remains to be done. While China has established an extensive network of nature reserves and protected areas, encompassing more than 16% of the total land area, insufficient budgetary and staffing commitments are common limitations in their management structures. Ex-situ conservation is also deficient, primarily because the botanical gardens are not representative of several local floras, nor are they often of adequate size or representative of endangered species. The lack of effective and efficient environmental legislation and education are also problems that continue to accelerate the loss of plant biodiversity in China.  相似文献   

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