整合多重生态保护目标的广东省生态安全格局构建

构建生态安全格局是缓解生态保护与经济发展之间的突出矛盾,保障可持续发展的有效空间途径。但目前生态安全格局的构建过于强调综合,简单叠加多种生态系统服务的方法忽视了不同服务间的权衡与协同关系,难以直接支撑不同目标下的生态保护决策。以广东省为例,重点关注生境维持、水源涵养、水质净化、粮食生产、土壤保持、洪水调节、沿海灾害缓解七种重要的生态系统服务,面向生物多样性保育、水资源利用、粮食生产、自然灾害防范等单一生态保护目标分别构建生态安全格局。研究结果表明,面向生物多样性保育目标的生态安全格局呈“双屏障带”式分布,生态源地主要分布在粤北生态发展区;面向水资源利用目标的水安全格局呈“五江一带”式分布,重点保护区主要位于河湖水库及周边绿地;面向粮食生产目标的生态源地主要分布在广东省东西两翼;面向自然灾害防范目标的生态源地在珠三角、湛江市、汕头市少有分布,集中在粤北生态发展区。基于多种生态系统服务综合重要性判定生态源地,并整合单一生态保护目标下的多重源地,识别综合生态源地共49536.10 km~2,主要分布在珠三角外围和粤北生态发展区。基于最小累积阻力模型和电路模型,识别了总长度2268.07 km...     

基于生态敏感性和生态系统服务价值的昌黎县生态廊道构建

生态廊道的作用在于提供生物迁徙的路径、促进不同栖息地之间的物种交流.廊道的构建能够减轻因城市化速度加快导致景观破碎化带来的危害,对生物多样性的保护具有十分重要的意义.本文以昌黎县为研究区,以2015年土地利用现状为基础,采用生态敏感性评价和生态系统服务价值分析的综合结果确定生态源地,然后基于最小累积阻力模型(MCR)和最小成本路径方法生成潜在廊道,根据重力模型对关键廊道进行识别,最终得到研究区包括4条重要廊道和2条一般廊道在内的生态廊道体系,旨在促进昌黎县生态廊道建设工程的科学实施和保护生物多样性.结果表明:研究区生态敏感性总体一般,生态系统服务价值总体较差,两者均呈现出四周高于中间的特点.生态源地主要分布在北部碣石山风景区、东部滨海国有林场和西部水源保护地这3个区域,与研究区生态环境建设与保护规划(2011-2030年)确定的自然保护区高度吻合.研究区生态廊道总长112.66 km,其中,重要廊道47.61 km,一般廊道65.05 km,廊道的最佳宽度范围为30～60 m,生态廊道与生态源地大致构成了一个环形闭合区域,能够有效促进生物物种的迁徙和物质能量的交流.     

基于生态系统服务的生态安全格局构建与生态韧性评估——以长株潭城市群为例

构建生态安全格局对于保障区域生态安全、优化国土生态空间具有重要意义,科学评估生态韧性是城市高质量发展的重要议题之一。以长株潭城市群为研究对象,基于"源地识别-阻力面构建-廊道提取"的生态安全格局构建模式,定量评估固碳释氧、土壤保持和水源涵养三项生态系统服务功能以识别源地,结合自然和人为因素构建阻力面,使用Linkage Mapper工具基于最小成本路径理论识别生态廊道,提出了一套基于生态安全格局构建过程的生态韧性评估框架,并结合Fragstats和Conefor Sensinode软件对其进行综合评价。研究结果显示:(1)长株潭城市群共55块生态源地,面积为7747.75km²,占城市群总面积的27.58%,东部和南部源地较为集中,西部较分散,林地是生态源地的主要组成部分;生态廊道共113条,廊道总长度为1458.97km,平均长度为12.91km,主要分布于研究区西部和北部。(2)结合生态源地和生态廊道构建了长株潭城市群"一心一环"生态安全格局,可有效缓解长株潭城市群中部生态用地 "空心化"的格局。(3)研究区55块生态源地的韧性指数介于0.1265-0.4682之间,空间上呈现出东高西低,南高北低的特征;113条生态廊道的韧性指数介于0.0027-0.8002之间,韧性指数较高的廊道主要分布在研究区东部和南部,韧性指数较低的廊道分布在西部、中部和北部。西部和中部或将成为影响长株潭城市群生态安全的关键区域,在城市规划过程中应重点关注。研究结果对优化城市空间布局、维护区域生态安全和促进区域一体化发展具有重要意义,并为区域生态韧性的评估提供了新的思路。     

基于生态重要性和敏感性的西南山地生态安全格局构建——以云南省大理白族自治州为例

生态安全格局构建是快速城市扩张背景下缓解生态保护和土地开发矛盾、保证区域生态安全的有效途径。源地和阻力面是生态安全格局构建的重要基础,当前阻力面构建多关注生态要素而忽视与区域典型生态问题相对应的生态过程表征。以西南山地地区--云南省大理白族自治州为研究区,选取生物资源保护、水资源安全和营养物质保持等生态系统服务评估生态重要性从而识别源地,基于地质灾害、土壤侵蚀、石漠化等生态敏感性构建生态阻力面,并运用最小累积阻力模型识别组团廊道和景观廊道,从而构建山地生态安全格局。研究表明,大理州生态安全源地总面积14416.64 km~2,占全州土地总面积的50.93%;关键生态廊道分为组团廊道和景观廊道两类,分别长404.7 km和208.4 km,以"一轴三带"形式呈树状辐射分布。生态安全格局中的生态源地和廊道应成为低丘缓坡土地资源开发中的禁止开发区。生态重要性源地识别和生态敏感性阻力面分析方法可为生态安全格局构建提供新思路,研究结果对于大理州山地城镇建设的用地选择和空间扩张提供定量指引。     

Reconciling conservation and development in protected areas of the Global South

As cornerstones for biodiversity conservation, protected areas (PAs) are critical to safeguard biodiversity. However, PAs are criticized for their limited ecological effectiveness and their negative social impacts. This article seeks to provide an overview on the contested nature of PAs and places PAs in the tension field of conservation and development, which are diverging forces specifically in the Global South. A reconciliation of PAs as parts of a wider landscape of interlinked social-ecological systems may increase the potential of PAs to contribute to the sustainable development goals, including the creation of sustainable human-nature relationships, environmental health and landscape resilience. The environmental justice framework appears useful in the endeavour to improve the social-ecological integrity of current conservation practises and to increase the ability of PA systems to withstand shocks. Considering PAs as systems in which people and nature interact in manifold ways may help increase their integrity, but understanding these interactions requires sustainability researchers and conservation practitioners to recognize the plurality in value towards nature, nature understanding and conceptualisations. Such deep understanding seems pivotal in working towards synergies of sustainable use, biocultural diversity and wilderness. Concludingly, this article emphasizes the need for holistic approaches rather than sectoral specialisations and radicalisations to achieve arrays of sustainability goals.     

生态脆弱区生态安全格局构建研究

构建生态脆弱区生态安全格局对维护区域生态安全至关重要。传统的生态安全格局构建多以静态生态指示因子为基础指标,对重要物种的迁徙过程考虑较少,容易忽略生态服务和物种丰富度较低、但对物种迁徙具有重要意义的区域,造成栖息地功能性丧失。因此,以日喀则市为例,基于生境适宜性评价进行生态源地识别,从地形、土地利用等方面构建生态阻力评价指标体系,应用最小累积阻力模型（MCR）识别生态廊道,并将生态廊道与阻力脊线的交点作为生态节点,进而结合生态服务空间特征构建生态安全格局。结果表明：（1）生态源地以草地、未利用地、水域和林地为主,面积8.3万km²,主要集中在日喀则南部沟谷地区、中部雅江河谷地区和北部高山地区;（2）生态廊道累积长达5135 km,主要沿河流或者山体呈网状分布;（3）生态节点主要分布在南部边境地区,用地类型以未利用地为主,是未来需要加强保护的关键区域;（4）建议构建"两屏-一流域"的生态安全格局,保障全市生态安全。该区域总面积5.17万km²,约占市域总面积的29%,能够支持12种物种栖息及迁徙,并分别保护了全域72.0%的水源涵养极重要区、69.9%的土壤保持极重要区、57.5%的防风固沙极重要区和99.6%的碳固定极重要区。生态廊道和生态系统服务相结合构建区域生态安全格局可为脆弱区生态系统和物种保护提供决策工具。     

京津冀城市群生态网络构建与优化

生态安全是人类生活的基本保障,快速城镇化致使大型生态源地破碎化、岛屿化,生态环境问题日益严重。构建生态网络不仅能加强生态源地间的连通性,完善生态功能,还能提高生态系统的综合能力,改善恶化的生态环境问题。以京津冀为研究区,基于地理空间分析技术确定京津冀生态源地,对研究区内的林地、湿地、草地,结合生态红线等进行区域叠加从而完成源地提取;基于最小成本路径方法,考虑土地利用及高程影响因子,提取京津冀城市群生态廊道,分析统计廊道分布情况;结合重力模型与重要生态源地连通性筛选出京津冀重要生态廊道,叠加现有国道、河流构建生态网络,对重要生态节点进行分析。研究结果表明,生态源地面积占研究区总面积比例为21.76%,林地、湿地、草地面积占总生态源地面积分别为82.78%,11.05%,6.17%;不同地貌区域生态源地类型不同,林地主要分布在山区,湿地主要分布在平原区域,草地主要分布在研究区西北部;景观成本值平原区域高于草原和山区,北京、天津、石家庄城区及周边景观成本值最高;采用最小成本路径模型提取廊道579条,其中张家口、承德区域生态网络较好,平原区域生态源地及生态节点缺失较为严重。最后,对北京、天津、白洋淀、衡水湖等重点生态区域提出修复和保护意见,为京津冀城市群发展提供参考。此外,本研究对其他地区生态网络的构建提供理论依据与技术支持。     

基于最小累积阻力模型的东北地区生态安全格局构建

生态安全格局对于缓解生态保护与经济发展之间的矛盾具有积极意义。以东北地区为研究对象,综合参考《生态保护红线划定技术指南》、《全国生态功能区划》以及东北地区自然资源禀赋和社会经济发展水平,基于水源涵养、防风固沙、生物多样性维持与保护等功能指标和敏感性指标划分生态源地;利用夜间灯光数据修正基本生态阻力面,并运用最小累积阻力模型划分缓冲区、识别生态廊道和生态战略节点,从而构建东北地区生态安全格局。结果表明:东北地区生态源地总面积为6.50×10⁵km²,占全区土地总面积的45.02%,包括18个生态源地,主要分布在大兴安岭、小兴安岭、长白山脉和西部草原的部分区域;划分了高、中、低3个水平缓冲区,关键生态廊道中心线总长11073.52km,生态战略节点29个,在东北地区形成以生态源地为中心的网状空间布局。结果可为保障区域生态系统服务功能和可持续发展政策的制定提供科学参考。     

Protected Areas in Tropical Africa: Assessing Threats and Conservation Activities

Numerous protected areas (PAs) have been created in Africa to safeguard wildlife and other natural resources. However, significant threats from anthropogenic activities and decline of wildlife populations persist, while conservation efforts in most PAs are still minimal. We assessed the impact level of the most common threats to wildlife within PAs in tropical Africa and the relationship of conservation activities with threat impact level. We collated data on 98 PAs with tropical forest cover from 15 countries across West, Central and East Africa. For this, we assembled information about local threats as well as conservation activities from published and unpublished literature, and questionnaires sent to long-term field workers. We constructed general linear models to test the significance of specific conservation activities in relation to the threat impact level. Subsistence and commercial hunting were identified as the most common direct threats to wildlife and found to be most prevalent in West and Central Africa. Agriculture and logging represented the most common indirect threats, and were most prevalent in West Africa. We found that the long-term presence of conservation activities (such as law enforcement, research and tourism) was associated with lower threat impact levels. Our results highlight deficiencies in the management effectiveness of several PAs across tropical Africa, and conclude that PA management should invest more into conservation activities with long-term duration.     

基于生态廊道识别的拉萨河流域生态安全格局构建

构建生态安全格局对于保障区域生态安全、优化国土生态空间具有重要意义。以拉萨河流域为研究区,基于“生态源地-阻力面-生态廊道”的区域生态安全格局构建范式,评估流域土壤保持、水源涵养、固碳、生境质量四项生态系统服务,基于生态系统服务重要性分级识别生态源地;选择土地覆被类型、归一化植被指数、地形起伏度、坡度、距道路距离、距水体距离作为主要阻力因子,利用熵权法形成综合阻力面;利用Linkage Mapper工具基于最小成本路径理论识别生态廊道并判定生态节点,构建流域生态安全格局。结果表明：提取生态源地20个,总面积2531.42 km²,占研究区总面积的7.77%;生态廊道36条,总长度916.87 km,与拉萨河干流平行呈“二”字型分布;生态节点13个,集中分布在裸地、裸岩、低覆盖度草地等地类,构建以生态源地-生态廊道-生态节点组成的“面-线-点”结构生态网络。研究结果为拉萨河流域生态安全和生态经济协调提供数据支持,为区域生态保护与可持续发展提供科学参考。     

京津冀地区的生态质量定量评价

生态质量的好坏标志着区域经济社会可持续发展的能力以及社会生产和人居环境稳定可协调的程度,如何定量评价区域生态质量状况与变化,协调其与城镇化的关系,日益成为城市生态学研究的热点.本文选择城市化发展迅速、生态环境问题突出的京津冀城市群为研究对象,基于遥感技术反演京津冀城市群植被覆盖度、生物量和人工表面比例、植被面积百分比等生态参数,结合植被破碎化指数,采用主成分分析法,构建了基于遥感参数的生态质量指数综合模型,定量评价了2000—2010年京津冀城市群生态质量及动态变化.结果表明: 本文构建的生态模型可以更客观、综合地定量评估城市与区域的生态质量状况与变化.2000—2010年,京津冀城市群的生态质量指数从2.38上升到2.84,增幅达19.3%.其中,2000—2005年的增幅(12.2%)高于2006—2010年(7.2%).从空间分布来看,生态质量指数的高值区位于京津冀北部,西部、东南部较低.不同城市的生态质量状况及变化趋势不同.承德的生态质量状况最好,并显著高于其他城市;其次为北京、秦皇岛和保定;天津的生态质量最差.承德、北京、秦皇岛和保定的生态质量高于京津冀地区的平均水平;廊坊、天津和沧州的生态质量明显低于平均水平.2000—2010年间,除唐山外,其他城市的生态质量均呈好转趋势.其中,沧州、衡水的生态质量指数提升最显著,增幅分别达520.5%和171.8%.     

Response of the endangered tropical dry forests to climate change and the role of Mexican Protected Areas for their conservation

Assuming that co‐distributed species are exposed to similar environmental conditions, ecological niche models (ENMs) of bird and plant species inhabiting tropical dry forests (TDFs) in Mexico were developed to evaluate future projections of their distribution for the years 2050 and 2070. We used ENM‐based predictions and climatic data for two Global Climate Models, considering two Representative Concentration Pathway scenarios (RCP4.5/RCP8.5). We also evaluated the effects of habitat loss and the importance of the Mexican system of protected areas (PAs) on the projected models for a more detailed prediction of TDFs and to identify hot spots that require conservation actions. We identified four major distributional areas: the main one located along the Pacific Coast (from Sonora to Chiapas, including the Cape and Bajío regions, and the Balsas river basin), and three isolated areas: the Yucatán peninsula, central Veracruz, and southern Tamaulipas. When considering the effect of habitat loss, a significant reduction (~61%) of the TDFs predicted area occurred, whereas climate‐change models suggested (in comparison with the present distribution model) an increase in area of 3.0–10.0% and 3.0–9.0% for 2050 and 2070, respectively. In future scenarios, TDFs will occupy areas above its current average elevational distribution that are outside of its present geographical range. Our findings show that TDFs may persist in Mexican territory until the middle of the XXI century; however, the challenges about long‐term conservation are partially addressed (only 7% unaffected within the Mexican network of PAs) with the current Mexican PAs network. Based on our ENM approach, we suggest that a combination of models of species inhabiting present TDFs and taking into account change scenarios represent an invaluable tool to create new PAs and ecological corridors, as a response to the increasing levels of habitat destruction and the effects of climate change on this ecosystem.     

The Effects of Governmental Protected Areas and Social Initiatives for Land Protection on the Conservation of Mexican Amphibians

Traditionally, biodiversity conservation gap analyses have been focused on governmental protected areas (PAs). However, an increasing number of social initiatives in conservation (SICs) are promoting a new perspective for analysis. SICs include all of the efforts that society implements to conserve biodiversity, such as land protection, from private reserves to community zoning plans some of which have generated community-protected areas. This is the first attempt to analyze the status of conservation in Latin America when some of these social initiatives are included. The analyses were focused on amphibians because they are one of the most threatened groups worldwide. Mexico is not an exception, where more than 60% of its amphibians are endemic. We used a niche model approach to map the potential and real geographical distribution (extracting the transformed areas) of the endemic amphibians. Based on remnant distribution, all the species have suffered some degree of loss, but 36 species have lost more than 50% of their potential distribution. For 50 micro-endemic species we could not model their potential distribution range due to the small number of records per species, therefore the analyses were performed using these records directly. We then evaluated the efficiency of the existing set of governmental protected areas and established the contribution of social initiatives (private and community) for land protection for amphibian conservation. We found that most of the species have some proportion of their potential ecological niche distribution protected, but 20% are not protected at all within governmental PAs. 73% of endemic and 26% of micro-endemic amphibians are represented within SICs. However, 30 micro-endemic species are not represented within either governmental PAs or SICs. This study shows how the role of land conservation through social initiatives is therefore becoming a crucial element for an important number of species not protected by governmental PAs.     

Extinction threat to neglected Plinia edulis exacerbated by climate change,yet likely mitigated by conservation through sustainable use

Forecasting the impacts of climate change on species distribution has several implications for conservation. Plinia edulis is a rare and threatened tree species from Brazilian Atlantic Rainforest. In this study, we assessed the impact of global climate change on the distribution of P. edulis. Additionally, we evaluated the efficacy of the Brazilian protected network to conserve this species. Ecological niche models were built using the maximum entropy method based on occurrence records and environmental predictors. Models predicted a reduction of climatically suitable areas for P. edulis in all evaluated scenarios in the coming years. Furthermore, we observed that Brazilian protected areas (PAs) are ineffective to conserve this species. Given the fact that P. edulis is a promising tree species rarely found within Brazilian PAs and threatened by global climate change, we strongly recommend the cultivation of this multipurpose species in agroforestry systems, landscaping and homegardens in order to promote its conservation through sustainable use.     

考虑滑坡敏感性的天津市蓟州区生态网络构建

随着城镇水平不断提高,人口数量不断增加,滑坡、崩塌等地质灾害频发,天津市蓟州区的景观孤岛化和破碎化现象日益严重,生物多样性减少,生态价值和生态服务功能降低。以天津市蓟州区为研究区,从自然资源、气候调节、水源涵养、生物多样性等方面考虑,选取生态源地;选取坡度、地形起伏度、坡向等滑坡孕灾环境因子,基于信息量模型,在定量分析滑坡与各孕灾环境因子关系的基础上通过地图代数计算滑坡敏感性指数,并用于修正由土地利用类型赋值得到的生态基本阻力面,基于最小费用模型提取研究区生态廊道,进而构建天津市蓟州区生态网络。研究结果表明:研究区内滑坡的空间分布主要受坡度、高程、地形起伏度以及岩土类型等因素的控制;经验证基于信息量模型计算得到的滑坡敏感性指数对研究区内的滑坡具有较强的诊断能力;基于最小费用模型,提取生态廊道23条,总长度约为129 km。通过对比分析,提取的生态廊道基本上避开了滑坡灾害的高敏感性区域,能够有效地将生态源地进行连接;生态廊道在蓟州区的空间分布存在显著的差异,主要分布在蓟州区的北部山区,生态廊道的密度较高,在蓟州区的中部和南部地区,生态廊道的分布非常稀疏。研究成果将为天津市蓟州区生态网络的优化、生态安全格局的构建提供科学依据。     

Corridors for jaguar (Panthera onca) in Mexico: Conservation strategies

Several species of carnivores, as jaguar, live in low densities and require extent habitat areas for survive. One of their main threats is fragmentation and demographic isolation. Identifying the habitat corridors, we can help the conservation of these species. We identified the viable and potential corridors between jaguar management and conservation areas for Panthera onca in Mexico. We considerate an ensemble model of the potential distribution of P. onca in Mexico, from which were identified jaguar management and conservation areas (JCMA). According to these attributes, we identified the possible habitat corridors between the JCMA with Corridor Designer. Thirteen habitat corridors were between all JCMA. However only seven were viable corridors and six were potential corridors. Also, in two areas of potential corridors were identified Stepping Stones that can help the jaguar movement between large fragments. In the thirteen habitat corridors, the main threats for jaguars are habitat fragmentation, roads, highway and possible conflict human-wildlife (livestock predation). The results from this work can provide the bases to take actions on the protection of connecting zones and alleviate the mortality of wildlife in these areas.     

Tropical dry woodland loss occurs disproportionately in areas of highest conservation value

Tropical and subtropical dry woodlands are rich in biodiversity and carbon. Yet, many of these woodlands are under high deforestation pressure and remain weakly protected. Here, we assessed how deforestation dynamics relate to areas of woodland protection and to conservation priorities across the world's tropical dry woodlands. Specifically, we characterized different types of deforestation frontier from 2000 to 2020 and compared them to protected areas (PAs), Indigenous Peoples' lands and conservation areas for biodiversity, carbon and water. We found that global conservation priorities were always overrepresented in tropical dry woodlands compared to the rest of the globe (between 4% and 96% more than expected, depending on the type of conservation priority). Moreover, about 41% of all dry woodlands were characterized as deforestation frontiers, and these frontiers have been falling disproportionately in areas with important regional (i.e. tropical dry woodland) conservation assets. While deforestation frontiers were identified within all tropical dry woodland classes of woodland protection, they were lower than the average within protected areas coinciding with Indigenous Peoples' lands (23%), and within other PAs (28%). However, within PAs, deforestation frontiers have also been disproportionately affecting regional conservation assets. Many emerging deforestation frontiers were identified outside but close to PAs, highlighting a growing threat that the conserved areas of dry woodland will become isolated. Understanding how deforestation frontiers coincide with major types of current woodland protection can help target context-specific conservation policies and interventions to tropical dry woodland conservation assets (e.g. PAs in which deforestation is rampant require stronger enforcement, inactive deforestation frontiers could benefit from restoration). Our analyses also identify recurring patterns that can be used to test the transferability of governance approaches and promote learning across social–ecological contexts.     

Policy indicators for use in impact evaluations of protected area networks

The number of protected areas (PAs) has steadily increased in the past 20 years, but their effectiveness to meet conservation targets is consistently questioned. Most conservation impact evaluations of protected areas assume that formal designations, like that of IUCN categories, reflect site-specific conservation rules, but this is not always true. In this paper we illustrate how conservation rules could be empirically assessed by use of content analysis combined with optimal scaling. This flexible methodology allows us to quantitatively assess strictness levels for use in conservation impact evaluations. The strictness measures could also indicate whether conservation rules are consistently applied in the different IUCN categories thereby providing guidance for future assignment of PAs to the IUCN protected area management categories. We illustrate how policy indicators based on conservation rules could be developed in two contrasting mountain protected area networks in Norway and in British Columbia (BC), including a total of 48 PAs in Norway and 51 in BC. Conservation rules for recreational use, motorized access and resource use were quantitatively assessed, thus providing a measure of how strictly PAs regulate the different human activities. Our results show that the main differences in strictness are between the two countries, followed by the contrast between national parks and provincial parks in BC. Overall, Norway has a more liberal conservation policy than BC and older national parks in BC have a much stricter conservation policy than most of the other PAs in this study. Overarching conservation objectives did not reflect the level of strictness (the conservation rules) that guide the daily management of individual PAs. This applies to both countries. We recommend to empirically investigate site-specific conservation rules to include de facto management of human activities in conservation policy impact evaluations. The methodology is also useful for monitoring downgrading of the protected area status, which is a result of authorizing human activities that are not consistent with conservation objectives.     

景观规划中的生态廊道宽度

生态廊道具有保护生物多样性、过滤污染物、防止水土流失、防风固沙、调控洪水等多种功能。建立生态廊道是景观生态规划的重要方法,是解决当前人类剧烈活动造成的景观破碎化以及随之而来的众多环境问题的重要措施。按照生态廊道的主要结构与功能,可将其分为线状生态廊道、带状生态廊道和河流廊道3种类型。生态廊道设计包括的关键问题有廊道数目、本底、宽度、联接度、构成要素、关键点(区)等。由于生态廊道结构与功能的复杂性,使得廊道的宽度具有很大的不确定性。具体的讲,生态廊道的宽度由保护目标、植被情况、廊道功能、周围土地利用,廊道长度等多个因素决定。合适的廊道宽度应该根据对廊道主要生态过程的研究来确定。从景观的结构与功能分析出发,分别从生物保护廊道和河流廊道两方面对生态廊道的宽度及其影响因素进行分析,并对相关研究成果进行综述,总结得出两种类型生态廊道的适宜宽度值范围。最后提出确定宽度时应该注意的相关问题。     

Applying a systematic conservation planning tool and ecological risk index for spatial prioritization and optimization of protected area networks in Iran

One of the key purposes of conservation selection strategies is to design a network of sites to support relevant biodiversity components and, therefore, decrease the risk of populations becoming isolated. To this end, it is important to be aware of the habitat locations of the target species and the threats of human activities, in order to identify areas of a high conservation priority. This paper takes the Chaharmahal and Bakhtiari province (Iran) as a case study, to highlight a network optimization for six target species of conservation concern, including the Persian leopard, Panthera pardus Pocock, wild sheep, Ovis orientalis Gmelin and wild goat, Capra aegagrus Erxleben. To run the optimization, we first generated the following input data: we modelled suitable habitats, using the InVEST model (Integrated Valuation of Environmental Services and Tradeoffs) and simulated the ecological impact of road networks (Spatial Road Disturbance Index (SPROADI), Kernel Density Estimation (KDE) and the Landscape Ecological Risk Index (ERI)). A visual inspection of the input data revealed that a large percentage of the study area constitutes a suitable habitat for the target species, however, the disturbances caused by the road demonstrate that the central and north-eastern regions of the study area are significantly affected. Indeed, approximately 10% and 25% of the study area are in the high and medium risk categories, respectively. Optimization using Marxan, shows that the north-western and southern regions of the study area should be given high conservation priority, necessary for an efficient conservation network. Habitats located in the north-central region should act as stepping-stone areas or corridors between the isolated regions in the north-east and the well-connected areas in the north-west and south. Overall, the findings of the present study show that the current network of protected areas is not contradictory to that suggested by Marxan, but has deficiencies in terms of size and stepping-stones.