基于MCR和重力模型的县域生态安全格局构建——以福建省永春县为例

[目的] 构建具有区域特色的生态安全格局,为生态环境的保护及县域尺度下的生态安全格局构建和分区管理提供科学参考。[方法] 以福建省永春县为研究对象,参考《生态保护红线划定指南》,选取水土保持、水源涵养、生物多样性保护及对永春县生态具有重要作用的林业保护共4项指标进行定量评估,以识别源地;利用最小累计阻力模型(minimal cumulative resistance, MCR)和重力模型的方法,构建生态廊道并对廊道的重要性进行分级评价,提取生态节点,构建永春县生态安全格局。[结果] 识别出的永春县生态源地共11块,总面积为64.8 km²,占区域总面积的4.45%;构建了55条生态廊道和27个生态节点,其中重要廊道25条,次要廊道30条,集中在中部和东部地区呈网状分布。[结论] 依据生态源地识别和廊道划分结果,构建了永春县以源地为核心,廊道为网络,生态节点为重点的生态安全格局框架,生态源地间相互作用强度差异明显,中部地区源地分布密度和生态廊道稳定性大于西部地区,应作为重点保护区域。     

Effects of width, edge and habitat on the abundance and nesting success of scrub–shrub birds in powerline corridors

Concern about declines in scrub–shrub bird populations has resulted in efforts to create and maintain habitat for these species. Vegetation within powerline corridors is managed to prevent contact of vegetation with transmission lines, and comprises approximately 2% of all of habitat for scrub–shrub birds in southern New England. Although previous studies have documented the use of powerline corridors by scrub–shrub birds, important questions remain about the factors affecting the quality of corridors as habitat for these species. We surveyed birds and monitored nests on 15 corridors in western Massachusetts during 2002 and 2003 to determine whether scrub–shrub birds occupy and successfully reproduce in powerline corridors, and to identify the principal factors affecting scrub–shrub abundance and nesting success. We found that corridors were occupied by scrub–shrub birds of high regional conservation priority, however, four of seven focal scrub–shrub bird species were scarce or absent in narrow corridors, and the abundance of these species was highest in corridors of intermediate width. Overall, nest survival was low (0.14) at these sites relative to other types of early successional habitats in the region, however, if we consider only our sites that were wider than the median width (49 m), nest survival in corridors was (0.33), similar to survival rates reported in other studies of scrub–shrub birds. We conclude that powerline corridors provide habitat for early successional birds of conservation concern, with wider corridors (50 m) contributing more to regional conservation of these species.     

Size of protected areas is the main determinant of species diversity in orchids

Efficient allocation of conservation resources will be achieved only if the priorities for biodiversity conservation – the “hotspots” – are correctly defined. To achieve this we need to pinpoint the main determinants of species diversity. Area, energy available and latitude are thought to be the most important determinants of species richness. Area is clearly the most important, but the relative importance of the other two is uncertain. To test the relative importance of energy available and latitude, data on the species richness of orchids was collected for various countries in the world, the influence of area factored out and the residuals correlated with energy available at these countries and with latitude. This was performed for both total area and that of the protected areas for the 67 countries from five continents, in order to determine which gives a better prediction. We show that – at the large scale considered – area is always very important, latitude is more important than energy available and the size of the protected areas gives a better fit than the total area of the country in most cases. This implies that conservation efforts should be directed to maximizing the size of the protected areas in each country.     

Integrating occupancy modeling and interview data for corridor identification: A case study for jaguars in Nicaragua

Corridors are critical elements in the long-term conservation of wide-ranging species like the jaguar (Panthera onca). Jaguar corridors across the range of the species were initially identified using a GIS-based least-cost corridor model. However, due to inherent errors in remotely sensed data and model uncertainties, these corridors warrant field verification before conservation efforts can begin. We developed a novel corridor assessment protocol based on interview data and site occupancy modeling. We divided our pilot study area, in southeastern Nicaragua, into 71, 6 × 6 km sampling units and conducted 160 structured interviews with local residents. Interviews were designed to collect data on jaguar and seven prey species so that detection/non-detection matrices could be constructed for each sampling unit. Jaguars were reportedly detected in 57% of the sampling units and had a detection probability of 28%. With the exception of white-lipped peccary, prey species were reportedly detected in 82–100% of the sampling units. Though the use of interview data may violate some assumptions of the occupancy modeling approach for determining ‘proportion of area occupied’, we countered these shortcomings through study design and interpreting the occupancy parameter, psi, as ‘probability of habitat used’. Probability of habitat use was modeled for each target species using single state or multistate models. A combination of the estimated probabilities of habitat use for jaguar and prey was selected to identify the final jaguar corridor. This protocol provides an efficient field methodology for identifying corridors for easily-identifiable species, across large study areas comprised of unprotected, private lands.     

Gaps in the protected area network for threatened Afrotropical birds

Protected areas established for wildlife conservation (IUCN category I-VI protected areas) or for forest and watershed conservation (forest reserves) across mainland sub-Saharan Africa have high biodiversity values. However, they fail to cover over half of the 106 threatened bird species, and thus leave these vulnerable to extinction. An analysis of Red List bird species that are not represented in existing reserves indicates gaps in the current network of protected areas, namely: Mt. Cameroon-Bamenda highlands (Cameroon), the Angolan scarp (Angola), the Drakensberg Highlands (South Africa), the Highveld (South Africa), the Eastern Arc Mountains (Tanzania), the eastern African coastal forest mosaic (Kenya and Tanzania), the Albertine Rift (Uganda, Rwanda, Burundi, eastern Democratic Republic of Congo and western Tanzania), and the Ethiopian Highlands. The addition of Forest Reserves to the existing protected areas closes some of the reservation gaps for threatened birds in Africa. We suggest that these Forest Reserves should be included within official lists of protected areas, and that National forestry authorities be encouraged to manage these areas. Publication of scientific articles showing the conservation value of Forest Reserves is needed to raise local and international support and funding.     

The influence of disturbance and habitat on the presence of non-native plant species along transport corridors

The impact from transportation corridors on surrounding habitat often reaches far beyond the edge of the corridor. The altered disturbance regime in plant communities along corridor edges and vehicle traffic facilitate the spread and establishment of invasive non-native plant species. We compared the frequency of non-native plant species along highways and railways and the ability of these species to invade grasslands and dense forests along these corridors. We measured the frequency of several non-native plant species along transects 0-150 m from the edge of highways and railways in grasslands and forests, as well as at control sites away from corridors. Both transportation corridors had higher frequency of non-native species than respective control sites. Grasslands had higher frequency of non-native species than forested habitats, but the frequency did not differ between the highways and the railways. The frequency of non-native species in grasslands along highways and railways was higher than at grassland control sites up to 150 m from the corridor edge, whereas the frequency in forested habitats along corridors was higher than at forested control sites up to only 10 m from the corridor edge. There was a significant decrease in the frequency of non-native species with increasing distance from both corridors in the forest, while grasslands showed no significant change in non-native species frequency with distance from corridors. This suggests that corridor edges and grassland habitats act as microhabitats for non-native species and are more prone to invasion than forests, especially if disturbed. Our results emphasize the importance of minimizing the disturbance of adjacent plant communities along highways and railways during construction and maintenance, particularly in grassland habitats and in areas sensitive to additional fragmentation and habitat loss.     

Bird community ecology on power-line corridors in East Tennessee

Breeding bird density and vegetation structure were determined during three breeding seasons in 14 plots on power-line corridors through forests in East Tennessee. The purpose was to describe the corridor bird community and to relate bird density and diversity to a number of environmental variables. The relative abundance of forbs, blackberry Rubus ssp., saplings, and areas of planted grasses varied significantly among plots. Thirteen bird species appeared to be attracted to the corridors. Seven of these species were classified as brush species, three as edge species, and three as generalist species, depending on their relative abundance in corridor, edge, and forest, respectively.Control of bird community density on the corridors was complex because individual species densities correlated significantly with several different variables. These variables were Rubus density and patchiness, sapling density and patchiness, corridor width, length of coniferous or deciduous forest edge, coverage of planted grasses, and number of years following vegetation maintenance by cutting.Bird community density varied among plots from 210 to 750 pairs km^?2, and increased asymptotically with Rubus density. Rubus density explained most of the variation and Rubus patchiness explained a significant additional portion. Species number varied little. Within plots, birds were registered significantly less often in grass-dominated areas than in forb-Rubus-dominated areas.     

Political ecology of wildlife conservation in the Mt. Meru area of Northeast Tanzania

The wildlife conservation problems in Tanzania are examined from a political ecology perspective. The analysis is historical, exploring the establishment of national parks under British colonial rule and the tightening of state control over access to resources at the expense of customary rights. Examples are presented from the Mt. Meru area of north-eastern Tanzania. During the colonial period, the formal political debate over land and resource rights was conducted without the participation of African peasants. After independence the state continued to assert control over resource access unilaterally. As Meru peasants have effectively been shut out of the formal political process, their only recourse for defending the loss of access to natural resources is everyday forms of resistance, including de facto alliances with commercial poachers and ‘foot dragging’ in regards to compliance with conservation laws. Consequently there is little local support for current wildlife conservation policies on Mt. Meru and wildlife populations have declined in the 30 years since Arusha National Park was established there.     

Interactions between protected areas and their surroundings in human-dominated tropical landscapes

Protected areas (PAs) often depend on landscapes surrounding them to maintain flows of organisms, water, nutrients, and energy. Park managers have little authority over the surrounding landscape although land use change and infrastructure development can have major impacts on the integrity of a PA. The need for scientifically-based regional-scale land use planning around protected areas is acute in human-dominated landscapes to balance conservation goals with livelihood needs for fuelwood, fodder, and other ecosystem services. As a first step, we propose the designation of a “zone of interaction” (ZOI) around PAs that encompasses hydrologic, ecological, and socioeconomic interactions between a PA and the surrounding landscape. We illustrate the concept by delineating the ZOI in three Indian PAs - Kanha, Ranthambore, and Nagarahole - using remote sensing, population census, and field data. The ZOI in Ranthambore is three times the size of the park and is largely defined by the socioeconomic interactions with surrounding villages. Ranthambore is located in headwaters and wildlife corridors are largely severed. In Nagarahole, the ZOI is more than seven times larger than the park and includes upstream watershed and elephant corridors. Kanha’s ZOI is approximately four times larger than the park and is mostly defined by contiguous surrounding forest. The three examples highlight the differing extents of ZOIs when applying equivalent criteria, even though all are located in densely-populated landscapes. Quantitative understanding of which activities (e.g. collection of forest products, grazing, road construction, tourism development) and which locations within the ZOI are most crucial to conservation goals will enable improved land use planning around PAs in human-dominated landscapes.     

Identifying and mapping biodiversity processes for conservation planning in islands: A case study in Réunion Island (Western Indian Ocean)

Over the last century, island biodiversity has become one of the most threatened in the world. Although many island conservation plans address biodiversity requirements at the species level, few plans address the spatial requirements of the biodiversity processes that underpin the persistence of these species. Using systematic conservation planning principles, we map the spatial components of biodiversity processes (SCBPs) and use these to design broad-scale conservation corridors for Réunion Island. Our method is based upon a literature review, expert knowledge, spatially explicit base data, conservation planning software, and spatial modelling. We combine a target-driven algorithm with least-cost path analyses to delineate optimal corridors for capturing key biodiversity processes while simultaneously considering biodiversity pattern targets, conservation opportunities, and future threats. We identify five SCBPs: the oceanic-terrestrial interface; riverine corridors; macrohabitat interfaces; the boundaries of isolated topographic units; and lowland-upland gradients. A large proportion of the SCBPs (81.3%) is currently untransformed, whereas 3% is irreversibly transformed by urbanisation and 15.7% is transformed but restorable. However, SCBPs are almost fully disrupted by urbanisation in the lowlands, thereby compromising functional corridors along full altitudinal gradients. This study is a contribution toward the reconciliation of conservation versus development objectives on Réunion Island but we believe that the delineation method is sufficiently general to be applied to other islands. Our results highlight the need for integrating marine, coastal and terrestrial conservation planning as a matter of urgency, given the rapid transformation of coastal areas on islands.     

Global analysis of the protection status of the world’s forests

This study presents a global analysis of forest cover and forest protection. An updated Global Forest Map (using MODIS2005) provided a current assessment of forest cover within 20 natural forest types. This map was overlaid onto WWF realms and ecoregions to gain additional biogeographic information on forest distribution. Using the 2008 World Database on Protected Areas, percentage forest cover protection was calculated globally, within forest types, realms and ecoregions, and within selected areas of global conservation importance. At the 10% tree cover threshold, global forest cover was 39 million km². Of this, 7.7% fell within protected areas under IUCN management categories I–IV. With the inclusion of IUCN categories V and VI, the level of global forest protection increased to 13.5%. Percentage forest protection (IUCN I–IV) varied greatly between realms from 5.5% (Palearctic) to 13.4% (Australasia), and for forest types from 3.2% (temperate freshwater swamp forest) to 28% (temperate broadleaf evergreen forest). Median protection of forest cover in 670 ecoregions (forest above a specified threshold) was 5.9% (IUCN I–IV); at IUCN I–VI, 46% of the ecoregions had less than 10% forest protection. Considering their biodiversity importance, forest protection within global priority areas was insufficient, e.g., median protection of 8.4% in biodiversity hotspots (IUCN I–IV). Results have policy relevance in terms of the target of the Convention on Biological Diversity (CBD), reconfirmed in 2008, to effectively conserve “at least 10% of each of the world’s forest types”. Regular updates of these analyses would allow progress towards achieving that target to be monitored.     

A range-wide model of landscape connectivity and conservation for the jaguar, Panthera onca

Large, wide-ranging carnivores face greater threats and more persistent declines than most other mammal species. An important conservation tool for these carnivores has been range-wide priority-setting exercises that have helped identify critical threats and key populations. However, such exercises often fail to identify functional movement corridors or account for genetic connectivity. We present a new model for jaguar (Panthera onca) conservation that uses a geographic information system (GIS) and expert input to create a dispersal cost surface and identify least-cost corridors connecting the 90 known populations across the jaguar’s range. Results indicate 78% of historic jaguar range, an area of approximately 14.9 million km², still holds potential for jaguar movement and dispersal. We identified 182 potential corridors between populations, ranging from 3 to 1607 km in length; 44 of these corridors are characterized as being of immediate concern due to their limited width, and thus their high potential for being severed. Resultant maps, displaying priority populations and corridors, are used to direct field-based research and conservation efforts. Field assessment and refinement of the corridors is ongoing. This is the first attempt to create and implement such a holistic model of range-wide conservation for a large carnivore species.     

Nature conservation as an integral part of optimal land use in East Africa: The case of the Masai ecosystem of Northern Tanzania

Many areas of East Africa show signs of misuse of natural resources by man. An improved use of these resources can be made if land use is integrated within the boundaries of a natural ecosystem, taking into account the long-term effects of exploitation, the potential of the land for different economic activities, and nature protection. In this paper the Masai Ecosystem of northern Tanzania is used as such a functional unit in which land use can be integrated. For this purpose this Ecosystem is described and its boundaries are defined. The potential (agricultural) land use for different areas within the boundaries are highlighted, and a review of the importance of the National Parks and Conservation Area for Tanzania's national economy is given. It is concluded that tourism can play an important role in the development of the country but within the Ecosystem the flow of tourists should be re-adjusted. Some of the Parks are more profitable than others but the most profitable appears to be over-utilised by tourists, while the least profitable is under-utilised. An alternative tourist circuit is proposed, and a number of recommendations are given to make better and safer use of the land with the new Agricultural Policy of the Government of Tanzania in mind. It is concluded that land use and nature conservation are tightly interlinked and that people and wildlife can both benefit from improvements aimed at integrated land use, agricultural development and higher economic returns.     

水鸟友好视角下的东莞市生态廊道与关键节点识别

[目的] 揭示目前广东省东莞市水鸟生态廊道的空间分布格局,为该区域生态修复提供科学依据。[方法] 以东莞市的关键物种水鸟为出发点,基于东莞市水域数据与阻力面构成数据,运用最小积累阻力模型算法、中性度原理、电流理论等方法开展研究。[结果] 在东莞市域范围内构建生态廊道共26条,总长度为259.91 km。其中重要、较为重要、一般重要的生态廊道各6条、15 条和5条。重要生态廊道与一般生态廊道以集中分布的情况出现,而较重要生态廊道呈现散布状态。所获取的关键障碍点空间位置特征多为人为干扰程度严重的区域。[结论] 在生态廊道空间布局方面,主要应以优化城市本底条件为基础,维持整个城市生态空间平衡;在廊道连通性提升角度,应以充分发挥廊道自生的生态功能为导向,保证整体廊道网络空间的连续性;在障碍点修复角度,应降低人类活动的强度干扰,减轻水鸟途经该廊道的阻碍。     

Wildlife conservation and mining of alluvial tin reserves in Southwest England

Several alluvial tin deposits in Cornwall have been evaluated for their significance to nature conservation in the British Isles. They have considerable wildlife interest because of the remarkable diversity of habitats resulting from former mining activity, in particular the areas of open water and hydroseral succession to the plagioclimax of Salix carr. Current interest in the commercial prospects of these sites leads to a potential conflict between wildlife conservation and mineral extraction. The means by which these contrasting objectives can be reconciled are examined using biological surveys to establish a selective conservation policy and an objective approach to landscape redevelopment.     

利用OWA和电路模型优化黄河流域甘肃段生态安全格局

从生态系统服务视角出发优化生态安全格局,对于维护区域生态安全格局,确保经济社会稳定发展意义重大,但现有研究缺乏对多种生态系统服务之间权衡情景下生态系统状况的认知。该研究以黄河流域甘肃段为研究单元,在测度2019年食物供给、碳固定、产水量、土壤保持及生境质量5种典型生态系统服务的基础上,利用有序加权平均(Ordered Weighted Averaging,OWA)模型识别出生态系统服务权衡度最高的优先保护区作为生态源地,利用最小累积阻力模型和电路模型识别生态廊道和战略点区域,进行生态安全格局构建与优化。结果表明:黄河流域甘肃段生态源地斑块共计169个,总面积27 460.56 km2,约占研究区总面积的19.2%。5种生态系统服务之间在全流域尺度下呈现出协同关系,甘南高原、陇中、陇东黄土高原由于受地形气候和植被覆盖以及人类活动的影响,生态系统服务差异显著。利用电路模型提取得到441条生态廊道,总体呈网状分布,贯穿东西,识别出生态节点49个。提出构建"四轴、六区、多中心"的黄河流域甘肃段生态安全空间布局优化体系,形成功能化、网络化的区域生态空间优化结构。     

基于生态系统服务价值评价的忻州市生态安全格局构建

[目的]准确识别生态保护的重要节点和区域,进而合理布局及建设生态廊道,维护生态系统可持续发展。[方法]以忻州市为例,基于生态源地-阻力面-生态网络的生态安全格局构建方法,通过生态系统服务价值评价及形态学空间学格局分析方法(MSPA)识别生态源地;基于熵权法和多阻力因子构建阻力面;运用电路理论模拟分析生态廊道和生态节点,确定生态修复的一些关键区域。[结果](1)研究区内含有生态源地59处,总面积为2 355 km²,呈现出东部集中,中西部分散的空间分布格局。(2)研究区共有生态廊道100条左右(总长度为1 637.58 km),生态夹点111处(总面积为3.16 km²)以及生态障碍点83处(总面积为48.7 km²),生态廊道按其重要程度呈现自内向外的环形分布,而生态夹点则主要散布在生态源区和廊道相互毗邻的区域。[结论]生态安全格局能够有效识别生态廊道以及生态修复的重要区域。在生态保护与恢复中,应将“保护廊道、修复夹点区域、剔除和完善障碍区域”作为总体治理策略。     

Community, lions, livestock and money: A spatial and social analysis of attitudes to wildlife and the conservation value of tourism in a human–carnivore conflict in Botswana

We quantified livestock (cattle, shoats, horses and donkeys) losses to lions (Panthera leo) and attitudes to lions, livestock losses and tourism among livestock owners, village residents and tourism workers around Makgadikgadi Pans National Park in Botswana. Losses were not correlated with the size or structure of livestock enclosures, numbers of dogs or herders. Rather losses increased with the amount of livestock owned. Most were stray animals preyed upon at night. Attitudes to wildlife, conservation and lions were also not consistently distributed within the society we studied. Negative attitudes to lions were almost ubiquitous among cattleposts but less widespread among people living in the more urbanized society of villages or among people working in tourism.Although four tourist camps were operating in the area, benefits from these operations were largely limited to employees. Despite considerable sums of money being paid to Botswana by local tourist facilities few respondents viewed tourism as valuable and most felt that the government and not they or their community was the main beneficiary of tourism. Tourism employees made up a small sub-section of the adult population drawn predominately from larger villages while the costs of livestock losses were spread among cattleposts near the park boundary. These same cattlepost respondents were not prepared to improve stock care to protect livestock, but indicated a willingness to kill lions instead. If tourism is to play a role in reducing human–wildlife conflict, communities must not be regarded as homogenous entities into which to distribute benefits evenly. Benefits might usefully be distributed in relation to the costs of coexisting with wildlife or used as incentives to better protect livestock or other human resources.     

Partnering with local communities to identify conservation priorities for endangered Grevy’s zebra

Setting wildlife conservation priorities and determining how to meet them is challenging, particularly when policy decisions made at large scales need to be informed by a diversity of local conditions. The persistence of species that range widely demands that they coexist with people both within and outside formally protected areas. It is often politically and financially infeasible for one central body, such as a government wildlife agency, to monitor an entire population. Therefore, conservation planners are increasingly turning to local knowledge to inform conservation decisions. Here, we show the scientific and conservation benefits of recruiting and training local community members to collect data on an endangered species, the Grevy’s zebra (Equus grevyi). We recruited 18 scouts from six community-held ranches in Samburu District, Kenya. The scouts record the location, group structure and habitat of all Grevy’s zebra herds seen in walking surveys. Kernel analyses of scout herd observations indicate areas heavily used by Grevy’s zebra, and the subset of these areas favored by females with young foals. The important areas identified by the scouts closely match those inferred from analyses of GPS radiocollar data. Further, scout data reveals extensive spatial and temporal overlap between livestock and Grevy’s zebra. This overlap suggests the potential for competition between Grevy’s zebra and domestic animals. We argue that scout programs such as ours can generate valuable insights for conservation planning. In addition, such programs have the potential to improve local attitudes toward wildlife conservation.     

Progressive impact of piecemeal infrastructure development on wild reindeer

We made monthly surveys of >2000 reindeer (Rangifer tarandus tarandus) from 1977 to 1987 before and after the construction of the Blue Lake hydroelectric reservoir in order to study the progressive impact of infrastructure development on wildlife. Following this development, reindeer densities within a 4-km radius declined gradually during winter to 8% of pre-development densities without significant changes in undeveloped control sites. During summer, reindeer gradually reduced use of areas within 4 km distance from roads and power lines to 36% of predevelopment density, with subsequent 217% increase in use of the few remaining sites located >4 km from infrastructure. Reindeer reproduction declined progressively as habitat was lost. Assessments of individual development projects seriously underestimate the long-term effects of the entire expanding infrastructure network. Piecemeal development has resulted in an estimated 70% loss of undisturbed reindeer habitat across the last century in Norway. During this time the reindeer population has become fragmented into 26 isolated sub-populations. Our results show that any further infrastructure development will put the remaining European population of wild mountain reindeer at great risk, as further habitat fragmentation will make the remaining undisturbed patches too small for holding viable populations. A general model of impacts of infrastructure on wildlife is presented. We discuss the importance of controlling piecemeal development in infrastructure for conservation of wildlife and argue that minimizing infrastructure development is likely one of the largest challenges in wildlife conservation ahead.