景观破碎化对生物多样性的影响

景观破碎化是生物多样性下降的最主要的原因之一。破碎化阻碍了种群间的基因交流,引起近交衰败;改变了物种生存所需的生物地理环境,减小物种的生存空间;改变了生态系统特性,影响系统内的能量平衡和物质流动加剧了外来物种的入侵。本文通过对上述方面的阐述,旨在更好地理解景观破碎化对生物多样性产生的深刻影响,并对下一步的研究方向进行了初步探讨。     

景观破碎化对动物适合度的影响研究综述

景观破碎化是生物多样性下降的主要原因之一,景观破碎化已成为保护生物学和生态学的中心问题之一。通常以岛屿生物地理学、异质种群生物学和景观生态学的理论来解释景观破碎化的生态学效应。以往研究表明,生境破碎化对动物适合度造成严重影响。文章通过综合文献,论述景观破碎化对动物适合度的影响,分析影响动物适合度的各项指标,包括物种生存能力,繁殖能力和子代存活能力：同时探讨研究中存在的问题,为物种的保护提出建议,并指出今后研究的主要方法、亟待解决的问题和研究热点。     

供水工程建设对生物多样性影响评价——以临沧澜沧江省级自然保护区为例

以临沧澜沧江省级自然保护区供水工程建设为例,系统调查分析评价供水工程建设对保护区评价区域生物多样性造成的影响程度。具体从供水工程建设对景观/生态系统、生物群落、物种/种群、主要保护对象、生物安全、社会因素6个方面产生的影响进行评价。评价结果表明,因工程建设涉及的区域小,不会对影响评价区的景观美学价值造成影响,不会造成天然生物群落的分割和破碎化,不会造成特有野生动植物物种的灭失或大量减少,对其栖息地环境的影响不显著,不会造成保护区生态环境的大面积破坏,造成其他外来物种及有害生物入侵的可能性较小,在施工期会对当地从事旅游业的社区群众产生一定影响。因此,拟建供水工程项目对评价区域生物多样性的影响程度为"较小影响"。提出在工程建设完成后建立澜沧江流域储水量变化监测站点等建议。     

森林生物多样性保护原理概述

热点地区的分析,为我们确定生物多样性保护的策略和优先等级提供了依据;由于人类的剧烈干扰,现在地球上有许多物种和生态系统都处于濒危的境地,热带雨林的生物多样性丧失最为严重;热点地区虽然在地球上所占的面积很小,但却拥有大量的物种,这些地区的生物多样性丧失应特别引起我们注意;每个物种灭绝的难易程度不同,稀有种和长寿命种特别易于灭绝,而关键种一旦受到威胁,依赖于其生存的许多物种也会有灭绝的危险。遗传多样性的丧失也是生物多样性丧失的重要方面,种群内遗传多样性的丧失主要来源于奠基者效应、统计瓶颈效应、遗传漂变和近亲交配４种因素。物种的概念影响到对物种的保护,物种保护应包括物种内遗传多样性的保护;种群的动态调节机制和源—汇种群动态对于生物多样性保护具有重要的意义。种群生存力分析是了解物种濒危机制的崭新手段。群落中的种间关系和自然干扰体系是生物多样性保护中应考虑的重要方面。人为的生境破碎与自然景观的异质性不同,生境破碎会造成边缘效应和拥挤效应等一系列的生物学后果。     

擦耳山风电场项目升压站公路建设对老蛇冲州级自然保护区生物多样性的影响评价

文章科学评价贵定县擦耳山风电场项目对麻江县老蛇冲州级自然保护区生物多样性造成的影响,并提出减缓生物多样性影响的措施和建议。从保护区景观(生态系统)、生物群落、种群(物种)、主要保护对象、生物安全、社会因素等六个方面的进行影响评价,计算生物多样性影响指数(BI)。项目建设对保护区生物多样性影响指数值BI为50.7,即项目建设对保护区的影响程度为“中低度影响”。     

新建溪水电站工程对湖北星斗山国家级自然保护区生物多样性影响评价

为准确评价新建溪水电站工程建设对湖北星斗山国家级自然保护区生物多样性造成的影响程度,全面调查评价区域的生物多样性现状。选取了了建设项目景观/生态系统、生物群落、种群/物种、主要保护对象、生物安全和社会等因子进行影响评价。评价结果为:拟建的水电站工程对保护区生物多样性的影响程度为"较小影响",同时针对项目建设带来的生态破坏提出了一些建议。     

保护生物学概述

对保护生物学的原理和方法作了概要的论述和探讨。主要内容为:（１）简史与基本原理。（２）生物多样性——物种多样性,遗传多样性,生态系统多样性。（３）生物多样性的丧失——地质时代的灭绝,种群生物学与灭绝,人类造成的灭绝,生境片断化造成的灭绝。（４）生物多样性的保护——自然保护区,广域地区的保护,恢复生态学。     

铁路建设工程对元江国家级自然保护区生物多样性影响评价研究

以元江国家级自然保护区为例,系统调查评价区域生物多样性现状,科学评价玉磨铁路建设工程对线路区域生物多样性造成的影响程度。从建设项目对景观/生态系统、生物群落(栖息地)、物种/种群、主要保护对象、生物安全、社会因素6个层次进行影响评价。评价结果认为,拟建的玉磨铁路项目对区域生物多样性的影响程度为"较小影响",并针对项目建设提出10条措施。     

输电线路对自然保护区生物多样性影响评价

工程建设项目在带来一定环境污染和生态环境破坏的同时,与保护区生物多样性保护的矛盾日益凸显。根据国家林业局相关技术规范,结合动物、植物、湿地调查等技术规程,对陕西周至国家级自然保护区生物多样性进行了现状调查,选取景观/生态系统、生物群落、种群/物种、主要保护对象、生物安全、社会因素等6项指标,定性和定量地分析输电线路工程建设可能对保护区造成的生物多样性影响。     

我国蝶类昆虫生物多样性研究进展

从遗传多样性、物种多样性、生态系统多样性和景观多样性四个层次分析了我国蝶类昆虫生物多样性研究进展;指出我国蝴蝶生物多样性研究主要集中在物种多样性研究上,少数涉及遗传多样性、生态系统多样性和景观多样性方面的研究报道;今后应加大蝴蝶多样性研究力度,特别是热点地区濒危蝴蝶多样性研究,从而为蝴蝶多样性保护提供依据。     

景观网络结构在株洲市城市绿地系统建设中的应用研究

景观网络结构侧重于反映景观功能,是描述景观生态过程的参数之一。将景观网络结构应用于城市绿地系统建设中,对于生物多样性的保护具有重要的意义。介绍了景观网络结构在株洲城市绿地系统中的应用,认为在城市绿地系统建设中,不仅要注重提高城市绿地景观的多样性,还应注意发挥城市绿地景观网络结构的作用,以确保城市绿地系统真正发挥维持城市生态系统生态平衡的作用。     

南宁市青秀山风景名胜区景观多样性探析

景观多样性是生物多样性研究的主要内容之一,在生物多样性保护方面具有重要作用。本文运用景观生态学原理,借助地理信息系统技术,选取景观多样性、优势度、丰富度密度、均匀度、分离度、分维数等指数,分析了南宁市青秀山风景名胜区不同景观类型的空间分布特征。结果显示:整个研究区域的多样性丰富,各景观类型所占比例相对均匀,常绿阔叶林和马尾松林的破碎化程度较轻,经济林和农田等人工景观较破碎,表明人为干扰十分强烈。     

Rapid assessment of biological richness in a part of Eastern Himalaya: an integrated three-tier approach

Biodiversity conservation necessitates not only preservation of single or multiple species but also the habitat as a whole along with its environment. Biological richness (BR) is a cumulative property of an ecological habitat and its surrounding environment, which has emerging implications in terms of management and planning. Six biodiversity attributes (i.e., spatial, phytosociological, social, physical, economical and ecological) were linked together based on their relative importance to qualitatively stratify biological richness of forest vegetation in Subansiri district of Eastern Himalaya using customized software, Bio_CAP. Higher biological richness was assigned to the habitats with (i) high species diversity, (ii) high degree of ecosystem uniqueness (EU), (iii) high economical value, (iv) complex terrain and (v) low disturbance level. This simple idea of integrated ‘three-tier modeling approach’ of (i) utilization of geospatial tools, (ii) limited field survey and (iii) landscape analysis; formed the basis of rapid assessment of biological richness.Satellite image interpretation using hybrid classification approach provided spatial distribution of vegetation types (corresponding to ecological habitats), with 89% accuracy. Landscape analysis was done using various quantitative indices that measured the heterogeneity and evaluated the patch characteristics. A methodology was developed for deriving relative adjacency weights from field data for calculation of juxtaposition of vegetation types. Biotic disturbance buffers (i.e., proximity zones around roads and human settlements) along with landscape parameters were combined to calculate disturbance index (DI), which in turn became an intermediate surrogate for BR assessment. Species diversity patterns along fragmentation and biotic disturbance gradients were adjudged to derive relative weights for DI computation. Species diversity (Shannon's index), ecosystem uniqueness (endemism status) and biodiversity value (BV) (total importance value (TIV)) were enumerated quantitatively that provided relative weights for BR computation. Terrain complexity (TC) was generated by calculating variance of the elevation image. Fifty-nine of total 764 species were found endemic to Eastern Himalaya with over all species endemism of 13 per ha. Shannon's index increased with decrease in fragmentation levels and increase of distance from sources of disturbance. BR index of the district was presented in five qualitative levels. Subtropical forests claim highest degree of biological richness as well as high disturbance index. This methodology has implications for rapid biodiversity assessment. Forest managers can use the DI and BR maps for gap analysis and prioritization of conservation activities viz., introduction of locale-specific species, thus protecting the forest habitats in situ.     

Relationships between avian richness and landscape structure at multiple scales using multiple landscapes

Little is known about factors that structure biodiversity on landscape scales, yet current land management protocols, such as forest certification programs, place an increasing emphasis on managing for sustainable biodiversity at landscape scales. We used a replicated landscape study to evaluate relationships between forest structure and avian diversity at both stand and landscape-levels. We used data on bird communities collected under comparable sampling protocols on four managed forests located across the Southeastern US to develop logistic regression models describing relationships between habitat factors and the distribution of overall richness and richness of selected guilds. Landscape models generated for eight of nine guilds showed a strong relationship between richness and both availability and configuration of landscape features. Diversity of topographic features and heterogeneity of forest structure were primary determinants of avian species richness. Forest heterogeneity, in both age and forest type, were strongly and positively associated with overall avian richness and richness for most guilds. Road density was associated positively but weakly with avian richness. Landscape variables dominated all models generated, but no consistent patterns in metrics or scale were evident. Model fit was strong for neotropical migrants and relatively weak for short-distance migrants and resident species. Our models provide a tool that will allow managers to evaluate and demonstrate quantitatively how management practices affect avian diversity on landscapes.     

大连市域景观生态格局优化发展研究

景观生态格局优化是景观生态规划的重要任务之一,在生物多样性保护和环境改善方面具有重要作用,是一个区域生态安全的基础。文章首先对大连市域自然现状和发展中存在的生态问题进行分析和识别,然后有针对地综述相关的景观生态学理论。在总结斑块、生态廊道的设计原理及总体布局模式的基础上,充分应用生态边缘效应原理、生态网络原理,提出了大连市域景观生态格局优化模式,并提出实现该格局的政策指引。     

壶瓶山生物多样性面临的威胁因素分析及保护对策

在全球环境基金(GEF)组织的资助下,2003年8月~2004年10月,对湖南省壶瓶山自然保护区社会经济和生物资源本底进行了调查。研究结果表明:壶瓶山自然保护区具有丰富的物种多样性、生态系统多样性和景观多样性,同时也面临着一些威胁和限制因素。为加强生物多样性的保护,2005年1月~2007年12月,又对该保护区内的重点保护物种、林火隐患、薪材需求、林木采伐、生态旅游、采矿、猎捕、放牧及道路建设等方面进行了监测,并运用逻辑分析法和对比分析法,对当前生物多样性保护仍面临的主要威胁与限制因素进行了探讨,并在此基础上提出了相应对策。     

湖南黄桑国家级自然保护区植被景观格局探讨

①斑块特征指数分析表明:各景观类型的密度、分维数指数都较小,植被景观的深展指数都不高,扩散比较均匀,没有极端复杂的形状产生,植被景观在演替系列中还没有普遍达到演替的顶级,斑块之间自相似程度较高。②多样性指数分析表明:总体多样性程度高。景观多样性指数、优势度指数与均匀度指数的结果所包含的意义一致,这种一致性充分说明了各植被景观类型分布均匀,各景观类型地位相差较小。③空间构型指数分析表明:保护区的斑块密度为1.001,即1 km2上有1.001个斑块。这说明斑块数目较少。各景观类型分布也较均匀。保护区景观破碎度指数为0.007,这表明该区植被景观在研究期内所表现的生境破碎化程度是很低的。每一植被景观类型破碎度指数最高的是灌丛和灌草丛景观,其次为栲林景观,其余的破碎度都处于较低的水平。内部生境破碎化指数以灌丛和灌草丛景观、栲林景观为最低,它们的单独斑块面积较大,故破碎化指数较低。其它景观类型的破碎化指数相差不大,这与植被顺向演替是相关的。景观分离度指数的排序结果与斑块密度的排序基本一致。     

An Ecological Framework for Planning for Forest Health

Concerns for maintaining biodiversity have led to the adoption of ecosystem management as the paradigm for federal land management. This approach will identify desired future conditions as the goal for management, based on ecological objectives for a given landscape. Some management efforts attempt to identify desired future conditions based on existing successional stages as defined by a classification of overstory vegetation types. Such an approach ignores most of the underlying ecological parameters of the landscape, and is inadequate for identifying past disturbance regimes and future successional pathways. An assessment of desired future conditions based on an ecological classification system is essential to overcome these inadequacies. The strategy proposed in this paper uses an appropriate ecological land classification, based on either ecological land types or habitat types, included in a broader hierarchical classification system. It also uses a vegetation map of existing overstory vegetation. These two maps are overlaid to generate polygons of ecological units that can then be used to create an ecosystem diversity matrix. Each polygon (stand) can be evaluated as to its composition and structure relative to its possible placement within the ecosystem diversity matrix through comparisons with historical ranges of variability. The overall ecosystem diversity matrix can then be examined in terms of the distribution of successional stages within each habitat type or ecological land type. The goal should be to maintain at least adequate ecological representation of all successional stages within each habitat type that occurred historically, based on past disturbance regimes. Adequate ecological representation is defined as sufficient size and distribution of inherent ecosystems to maintain viable populations of all endemic species dependent on these ecosystems. This approach can maintain and enhance regional biodiversity, but also maintain flexibility in land management options.     

海南岛热带森林生物多样性研究进展

生物多样性是生态学研究中一个重要的领域,海南岛热带林有很高的生物多样性。阐述海南岛热带林生物多样性的意义和研究进展,介绍海南岛热带林物种多样性、遗传多样性、生态系统多样性和景观多样性特点,结合生物多样性锐减的现状提出了相应的保护建议。