城市生态网络分析研究进展

自生态网络分析方法提出40多年来,其理论发展和应用实践不断拓展,但直至21世纪才不断引入到城市生态系统研究中,用以分析城市内部多个主体和多种生态流构成的关联网络。目前,城市生态网络分析集中于生态网络分析方法与指标的拓展及多尺度的应用研究,而生态网络分析方法又形成了上升性分析和环境元分析两大分支,多尺度应用涵盖了城市镶嵌的区域背景尺度和城市内部产业部门之间的细节尺度。然而,当前研究仍存在着多尺度融合、多种生态网络分析方法集成不足等问题,这限制了城市生态网络分析方法在城市规划设计中的应用。未来城市生态网络分析研究集中于如下3点:(1)开展多尺度城市生态网络分析,包括城市群-城市-园区/社区等,构建多级嵌套生态网络模型;(2)集成上升性与环境元分析方法,提出由外在表征到内在过程的城市生态系统评价模式及模拟方法;(3)强调自然节点在城市生态网络中的重要作用,形成社会经济节点与自然节点并重的生态网络模型,并强调构建多精度的生态网络模型服务于不同的研究目的。     

生态网络分析方法研究综述

生态网络分析方法是分析生态系统作用关系、辨识系统内在、整体属性的一种有效的系统分析方法。总结了生态网络分析方法的主要研究成果:网络结构特性、网络稳定性、网络上升性、网络效能等;介绍了构建生态网络模型过程和群落构建规则;以德国西部城市诺伊斯河口氮循环为例,介绍David K是如何运用生态网络分析方法来揭示网络中的微动力流循环规律。生态网络分析方法的主要贡献:(1)对人们凭经验感知的生态系统分室间的关联关系,采用了严密的数学模型和推导进行了描述和证明;(2)为生态系统的微动力流循环的研究提供了方法,对生态系统中物质流的间接循环作用进行了科学论证;(3)不仅为分析生态系统提供了一种科学的数学方法,而且,它为探索生态系统提供了不同与牛顿世界观的崭新的认识论。总结与回顾生态网络分析方法,有益于该方法的运用和进一步完善。     

基于GIS、景观格局和网络分析法的厦门本岛生态网络规划

 以厦门本岛2000年Landsat-TM卫星影像解译的土地利用现状图、绿地系统现状图与规划图为基础资料,在地理信息系统（GIS）支持下,运用景观格局分析方法,选用多种景观指数,评价了厦门本岛绿地系统的现状与已有规划。在此基础上,应用网络分析法构建了旨在优化生态网络的不同新方案。通过α指数、β指数、γ指数等网络结构指数,进行不同方案的比较,从中选出最优的规划方案。将选出的生态网络E的廊道宽度设为50 m,叠加到厦门市绿地系统规划图上,并应用景观指数,定量评价了该优化方案对厦门本岛绿地系统的改善情况。其结果表明：该优化方案能使景观的破碎化程度得到改善,绿地斑块形状的复杂性程度进一步增加,景观连接度得到提高,说明优化方案生态网络E可进一步明显改善厦门本岛现有绿地系统的数量和质量。我们的研究结果也表明：应用景观指数和网络分析法相结合的方法,不仅可以定量评价城市绿地系统现状以及规划的合理性,而且可以优化城市生态网络的方案,使其更符合城市生态网络建设的整合性、和谐性、流通性、安全性、多样性和持续性原则。     

A conceptual framework for urban ecological restoration and rehabilitation

Urban greenspace has gained considerable attention during the last decades because of its relevance to wildlife conservation, human welfare, and climate change adaptation. Biodiversity loss and ecosystem degradation worldwide require the formation of new concepts of ecological restoration and rehabilitation aimed at improving ecosystem functions, services, and biodiversity conservation in cities. Although relict sites of natural and semi-natural ecosystems can be found in urban areas, environmental conditions and species composition of most urban ecosystems are highly modified, inducing the development of novel and hybrid ecosystems. A consequence of this ecological novelty is the lack of (semi-) natural reference systems available for defining restoration targets and assessing restoration success in urban areas. This hampers the implementation of ecological restoration in cities. In consideration of these challenges, we present a new conceptual framework that provides guidance and support for urban ecological restoration and rehabilitation by formulating restoration targets for different levels of ecological novelty (i.e., historic, hybrid, and novel ecosystems). To facilitate the restoration and rehabilitation of novel urban ecosystems, we recommend using established species-rich and well-functioning urban ecosystems as reference. Such urban reference systems are likely to be present in many cities. Highlighting their value in comparison to degraded ecosystems can stimulate and guide restoration initiatives. As urban restoration approaches must consider local history and site conditions, as well as citizens’ needs, it may also be advisable to focus the restoration of strongly altered urban ecosystems on selected ecosystem functions, services and/or biodiversity values. Ecosystem restoration and rehabilitation in cities can be either relatively inexpensive or costly, but even expensive measures can pay off when they effectively improve ecosystem services such as climate change mitigation or recreation. Successful re‐shaping and re-thinking of urban greenspace by involving citizens and other stakeholders will help to make our cities more sustainable in the future.     

Trophic networks: How do theories link ecosystem structure and functioning to stability properties? A review

In the context of present global changes, interest in understanding how systems respond to anthropogenic environmental pressures and stress has increased. Indices that characterize ecosystem state are helpful tools for the interpretation of ecosystem responses. The central question is how to link these responses to ecosystem structure and functioning and to quantify ecosystem persistence, resistance or resilience. Quantification and characterization of trophic networks by ecological network analysis (ENA) indices is proceeding rapidly, especially in the field of coastal ecology. In this contribution, we review several theories that relate ecosystem structure and function to stability. The structure and functioning of ecosystems change during the maturation of ecosystems. In the first section, the maturation of ecosystems is described using thermodynamics. In the second and third parts of this paper, we define some concepts for analysing structure and functioning of food webs and discuss their relation to stability. In the last section, we describe three ENA indices and their link to stability. We demonstrate that ENA provides powerful tools for describing local stability, combining quantitative and qualitative concepts. However, it remains incomplete for describing real conservation cases that combine local and global stability.     

焦作市景观生态规划研究

运用景观生态学原理,借助于地理信息系统技术,根据焦作市实际情况,将其景观构成要素分为耕地、园地、林地、居民点及工矿用地、水域和其它用地6个景观类型,采用景观多样性、景观优势度、景观破碎度和景观分离度等指标进行定量分析,归纳焦作市景观空间格局特征,提出焦作市景观生态规划的方案.焦作市的景观总体布局模式为：市域保留4~5个大型自然植被斑块,市区规划小型绿地斑块,生态廊道将大小绿地斑块联系起来,维持城市生态系统良性循环;适当合并居民点,形成以市区为中心,其外侧有博爱区、沁阳市等7个市、区的组团式城市群,通过快速干道相连,形成相对独立、相互依存、有机联系、协调发展的网络城市格局;城镇斑块镶嵌于以耕地、林地为背景的基质之中,以道路廊道、绿地廊道、水系廊道相连接,有利于保持物种多样性和景观异质性,改善城市生态环境.     

基于生态网络分析的南京主城区重要生态斑块识别

在城市化程度较高,用地极为紧张的大都市,识别重要的生态斑块对其进行保留和修复不仅对控制大城市的城市过度扩张、提升城市品质、优化人居环境具有重要意义,也具有较强可操作性。以南京市主城区为例,在GIS技术的支撑下,(1)将景观阻力分析和网络分析相结合,定量表征研究区的潜在生态廊道,构建生态网络,寻找生态节点;(2)对城市中生态斑块的特殊服务功能进行分析,筛选出具备河流生态防护、隔离工业污染和居民休闲功能的生态斑块;(3)对生态斑块的规模进行分析,提取面积较大的斑块。综合分析后识别出7个重要的节点斑块,建议对其进行立法保护和修复,划定为永久绿地或永久生态空间,并对其建设方向提出意见。     

The Urban Funnel Model and the Spatially Heterogeneous Ecological Footprint

Urban ecological systems are characterized by complex interactions between the natural environment and humans at multiple scales; for an individual urban ecosystem, the strongest interactions may occur at the local or regional spatial scale. At the regional scale, external ecosystems produce resources that are acquired and transported by humans to urban areas, where they are processed and consumed. The assimilation of diffuse human wastes and pollutants also occurs at the regional scale, with much of this process occurring external to the urban system. We developed the urban funnel model to conceptualize the integration of humans into their ecological context. The model captures this pattern and process of resource appropriation and waste generation by urban ecosystems at various spatial scales. This model is applied to individual cities using a modification of traditional ecological footprint (EF) analysis that is spatially explicit; the incorporation of spatial heterogeneity in calculating the EF greatly improves its accuracy. The method for EF analysis can be further modified to ensure that a certain proportion of potential ecosystem services are left for in situ processes. Combining EF models of human appropriation with ecosystem process models would help us to learn more about the effects of ecosystem service appropriation. By comparing the results for food and water, we were able to identify some of the potentially limiting ecological factors for cities. A comparison of the EFs for the 20 largest US cities showed the importance of urban location and interurban competition for ecosystem services. This study underscores the need to take multiple scales and spatial heterogeneity into consideration to expand our current understanding of human–ecosystem interactions. The urban funnel model and the spatially heterogeneous EF provide an effective means of achieving this goal. Received 17 October 2000; accepted 31 May 2001.     

江苏省自然遗产地生态网络的构建与优化

自然遗产地是生物的重要栖息场所,而生态网络是连接自然遗产地的有效途径,如何有效和合理地构建自然遗产地之间的生态廊道,连接破碎生境,对保护自然遗产地生物多样性和区域生态安全具有重要意义。在Arc GIS 9.3的技术支持下,通过合理估算阻力阈值,采用最小耗费距离模型分析方法,构建江苏省省域范围内的自然遗产地生态网络保护体系,并在网络连通性指数分析方法的基础上对生态网络的连通性和有效性进行评价,针对性地提出自然遗产地生态网络的优化措施。研究结果表明:78.28%的林地、88.70%的滩涂滩地、94.37%的草地是自然遗产地生态网络的主要景观组成结构;自然遗产斑块本身对生态网络的构建有较大影响,其中面积较大、长条型的斑块对维持景观连通性的重要性程度贡献较大;研究区现状整体生态连通性指数仅0.001—0.003,连通性水平较差,通过构建生态网络,整体连通性水平可提高到0.044—0.046,可能连通性水平可达到0.074,表明自然遗产廊道的构建可提高景观的连通性水平;在现有生态网络结构的基础上,增加破碎斑块间的生态连接是优化生态网络体系的可行性策略。     

基于生态安全格局的南京都市区生态控制边界划定

以南京都市区为例,通过生态敏感性分析获取了研究区既有的高生态敏感空间,采用最小费用路径方法辨识了对研究区具有重要生态意义的潜在生态廊道和生态关键区,采用图谱理论中的景观连接度指数辅助确定生态廊道宽度,构建了研究区潜在的生态网络。在此基础上,整合既有和潜在生态空间,科学划定生态控制边界,实现了研究区现存和潜在的重要自然生态空间保护。研究结果表明:1)生态敏感性分析能够识别出研究区既有的高生态敏感性区域,并指出其呈现出"大而孤立,小且分散,连接性不佳"的空间特征。2)遴选出的71处生态源地、119条重要廊道和61个关键生态斑块共同组成了研究区的生态网络,显著提升了原有生态空间的景观连接性和研究区域的总体生态安全水平。3)生态网络分析可以弥补敏感性分析只考虑既有自然生态空间的局限,二者的组合使用可为不同尺度上生态控制边界的划定提供简明的分析框架。研究结果可为南京都市区生态控制线划定和生态环境保护提供重要的参考,对其他城市生态控制边界的划定也具有一定的借鉴意义。     

Quantifying a virtual water metabolic network of the Metropolitan District of Quito,Ecuador using ecological network methods

Current human population is mostly located in urban areas making cities the center of attention in terms of achieving sustainability goals. Evidence shows that ecosystems have evolved over time toward a balanced configuration between resource efficiency and functional redundancy. For this reason, they are exemplary models to follow in terms of sustainability. Here, we apply similar ecological network-based methods to study the virtual water metabolic network (VWMN) of the Metropolitan District of Quito. The VWMN was obtained using novel bottom-up, survey-based methods to generate the urban metabolic network. We compare the VWMN results with those previously obtained from ecological food webs, to learn if there are insights about the sustainability of urban metabolic processes. We conclude that VWMN does not exhibit characteristics observed in sustainable ecological networks because this socioeconomic network exhibits higher levels of path redundancy. Urban metabolism studies are gaining in popularity as a research tool aimed at informing resource management and this is one of the first covering a city in the Global South and using a bottom-up survey method.     

基于MSPA与最小路径方法的巴中西部新城生态网络构建

目前快速城市化导致了生境斑块的日益破碎化,景观之间的连通性不断降低。构建生态网络可以连接破碎的生境斑块,增加绿地景观的连通性,对生物多样性保护具有重要意义。以高度景观破碎化的四川省巴中西部新城为研究区,采用形态学空间格局分析(MSPA)方法,提取出对研究区生态网络构建具有重要生态意义的核心区和桥接区两类景观要素,并选用整体连通性(IIC)、可能连通性(PC)和斑块重要性(d I)等景观指数,分别对核心区和桥接区进行景观连接度评价,遴选出对维持景观连通性贡献最大的10个核心区生境斑块作为生态网络的源地,并根据斑块对维持景观连通的重要性程度将其他核心区和桥接区进行类型划分,以此作为景观阻力的赋值依据,融入消费面模型中,最后采用最小路径方法构建了研究区潜在的生态网络,并基于重力模型对重要生态廊道进行了识别与提取,在此基础上有针对性地提出了生态网络优化的对策。研究结果表明,MSPA方法能够科学的辨识出研究区内对生态保护具有重要意义的结构性要素,例如作为物种栖息地的核心区和物种迁移通道的桥接区,这些要素是生态网络的重要组成部分;景观连通性的计算,明确了研究区景观要素的保护重点,为最小路径方法中的景观阻力赋值提供了重要的参考信息;基于MSPA与最小路径方法的生态网络分析框架综合了现有景观结构性要素识别、连通性分析以及物种潜在迁移路径分析等方法,将景观中潜在的生态源地和结构性廊道的连通性作为构建生态网络的重要基础和主要依据,从而使得生态网络的构建更科学。研究结果可为高度破碎化地区生态网络的构建提供重要的参考与依据,对其他地区生态网络的构建也具有一定的借鉴意义。     

湖南省城市群生态网络构建与优化

大型生境斑块为区域生物多样性保护提供了重要的空间保障。然而,快速城市化使得大型生境斑块变得日益破碎化、岛屿化,连接性不断下降,且日益受到周边土地利用变化的强烈影响,已严重威胁着区域生物多样性的保护。通过生态廊道建立或修复破碎生境斑块之间的连接,将非常有利于生态网络生态服务功能的有效发挥。基于景观生态学和保护生物学的相关原理,以湖南省城市群为例,在RS和GIS技术的支撑下,采用最小费用路径和情景分析方法,定量模拟了研究区的潜在生态廊道,基于重力模型对重要生态廊道进行了识别与提取,并就消费面模型对潜在生态网络结果产生的影响进行了分析,在此基础上有针对性地提出了生态网络优化的对策。研究结果表明,林地和耕地是组成研究区生态网络的优势景观要素类型;不同生境斑块间的相互作用强度差异显著,总体上西高东低,南高北低;消费面模型能够在较大程度上影响到生态网络的分析结果,因而进行情景分析十分重要和必要。研究结果可为研究区生态网络的构建和优化提供科学依据,同时可为其他城市群区域生态网络的构建提供参考和借鉴。     

景观生态网络研究进展

作为生态学重要的概念与方法,生态网络是景观生态学研究的热点问题,也是耦合景观结构、生态过程和功能的重要途径。景观生态网络对于保护生物多样性、维持生态平衡、增加景观连接度具有重要意义。从景观生态网络的相关理论、研究进展、研究方法模型等进行分析,并对其应用前景进行展望,主要介绍了传统景观格局分析、网络分析、模型模拟等方法的适用性与特点,并分析了景观生态网络在城市景观格局优化、自然保护区规划、生物多样性保护、土地规划等领域的应用,最后提出了研究的主要问题。     

基于物种分布的北京平原生态网络构建

高强度的城市化活动导致了生物栖息地破碎化、退化和消失,是生物多样性减少的主要原因。建立城市地区生态网络是保护生物多样性的重要途径。因其他物种数据可获得性差,以观测的典型鸟类群落为指示物种,探讨构建生态网络,可为城市生物多样性保护提供新思路。以北京市平原区为研究范围,重点基于86种鸟类分布大数据,通过Maxent模型掩膜生成栖息地源地并进行分级,在GIS技术的支撑下,以土地利用数据建立鸟类活动阻力面,采用最小累积阻力模型算法,模拟并形成了平原地区分级的生物多样性保护网络。研究结果表明,河湖湿地和城市公园组成了北京平原地区生态网络的优势景观类型,占平原区生态空间的81%。基于景观类型大小与物种数量的线性关系筛选出分级生物栖息地,其中一级生物栖息地58个,二级生物栖息地146个,通过模型模拟形成了平原地区生物多样性保护的一二级生态网络,共948条网络,长3760km。筛选出重要生态节点12处,关键生态廊道6条,是保护平原地区生物多样性的重要生态设施。该生态网络的实施对于提升首都平原区的生物多样性具有重要价值,研究结果可为国土生态空间优化提供重要科学依据和参考。     

基于生态系统服务供需的广东省绿地生态网络建设分区

绿地生态网络是城市地域生态持续性的重要保障,分区管控则是实现省域绿地生态网络差异化建设目标的基本原则。考虑到生态系统服务的供给和需求能够有效表征绿地生态网络建设的生态本底与生态需求,以县域为研究单元,采用修正的生态系统服务价值量核算生态系统服务供给量,以土地利用开发程度、人口密度和地均GDP表征生态系统服务需求量,基于供需分析提出广东省绿地生态网络建设分区方案。研究结果表明,按照各区县生态本底和生态需求差异分为四大类型区:Ⅰ城市生态节点保育型,包含13个区县,包含潮州市湘桥区、汕头市金平区、佛山市顺德区、广州市南沙区、黄埔区、荔湾区、越秀区、海珠区、深圳市盐田区、罗湖区、南山区、肇庆市端州区、珠海市金湾区等,为生态本底好-生态需求高的区域,在建设中应重点关注城市大型绿地游憩、科教等社会-生态复合功能;Ⅱ城市生境斑块修复型,包含34个区县,主要分布在珠三角核心区及粤东沿海地区,为生态本底差-生态需求高的区域,在建设中需要加大资金投入、完善城市绿色基础设施;Ⅲ为城郊潜在节点重构型,包含21个区县,主要分布在珠三角的江门、惠州、粤西沿海区域以及粤东中部,为生态本底差-生态需求低的区域,应以生态经济为导向,在产业空间重构的基础上,以城市反哺乡村,推进区域生态空间优化;Ⅳ城郊源地网络连通型,包含55个区县,主要分布在广东省北部地区,为生态本底好-生态需求低地区,应强化生态源地的保护,保障生态系统服务流向周边区域的持续输送。分区方案基本表征了广东省县域生态本底和生态需求的空间差异,能够为绿地生态网络建设提供规划指引。     

基于景观格局和网络分析法的崇明绿地系统现状和规划的评价

以崇明2005年卫星影像图、土地利用现状图为基础资料,结合崇明绿地系统规划,在地理信息系统支持下,选择崇明本岛面积大于10hm²的绿地作为节点,依照网络分析法,构建了不同的生态网络方案,通过α指数、β指数、γ指数以及成本比等网络结构指数进行不同网络方案的比较,从中选出最优的规划方案。然后在景观分析软件Fragstats支持下,运用景观格局分析方法,选用多种景观分析指数,在斑块类型层次上和景观层次上对崇明绿地系统现状、绿地系统规划以及优化后的生态网络规划方案从景观生态学角度进行了定量分析与评价,并针对现有的绿地系统规划提出了进一步完善的建议。研究结果表明崇明绿地系统规划有效地改善了绿地景观破碎化的问题,绿地斑块形状的复杂性程度增大,景观连接度得到提高,景观多样性和均匀性指数均得到较大幅度提升。而在现有绿地系统规划基础上做出的优化生态网络方案可进一步改善崇明本岛现有绿地系统的数量和质量。同时表明,生态网络分析结合景观格局分析是评价和改善绿地系统规划有效的途径。     

Industrial Ecosystems and Food Webs: An Expansion and Update of Existing Data for Eco‐Industrial Parks and Understanding the Ecological Food Webs They Wish to Mimic

Cyclical industrial networks are becoming highly desirable for their efficient use of resources and capital. Progress toward this ideal can be enhanced by mimicking the structure of naturally sustainable ecological food webs (FWs). The structures of cyclic industrial networks, sometimes known as eco‐industrial parks (EIPs), are compared to FWs using a variety of important structural ecological parameters. This comparison uses a comprehensive data set of 144 FWs that provides a more ecologically correct understanding of how FWs are organized than previous efforts. In conjunction, an expanded data set of 48 EIPs gives new insights into similarities and differences between the two network types. The new information shows that, at best, current EIPs are most similar to those FWs that lack the components that create a biologically desirable cyclical structure. We propose that FWs collected from 1993 onward should be used in comparisons with EIPs, given that these networks are much more likely to include important network functions that directly affect the structure. We also propose that the metrics used in an ecological analysis of EIPs be calculated from an FW matrix, as opposed to a community matrix, which, to this point, has been widely used. These new insights into the design of ecologically inspired industrial networks clarify the path toward superior material and energy cycling for environmental and financial success.     

Ecology and urban planning

Urban areas harbour diverse nature ranging from semi-natural habitats to wastelands, parks and other highly human-influenced biotopes with their associated species assemblages. Maintenance of this urban biodiversity for the residents and for its intrinsic value in the face of increasing population and expanding cities requires that ecological knowledge should be better integrated into urban planning. To achieve this goal understanding of ecological patterns and processes in urban ecosystems is needed. The first step in the necessary urban ecological research is to find out what kind of nature exists in cities. Second, knowledge about ecological processes important in urban nature is required. Although ecological processes in cities are the same as in rural areas, some of them, such as invasion by alien species, are more prevalent in urban than in rural conditions. Third, based on ecological knowledge, management schemes maintaining the diversity of urban nature should be designed. These procedures should also include protection of urban nature, e.g. in urban national parks. Finally, as ecology alone cannot provide the complex information about human influence on urban ecosystems, interdisciplinary research involving natural and social sciences is imperative for a holistic approach to integrating ecology into the process of urban planning.     

Analysing ecological networks of species interactions

Network approaches to ecological questions have been increasingly used, particularly in recent decades. The abstraction of ecological systems – such as communities – through networks of interactions between their components indeed provides a way to summarize this information with single objects. The methodological framework derived from graph theory also provides numerous approaches and measures to analyze these objects and can offer new perspectives on established ecological theories as well as tools to address new challenges. However, prior to using these methods to test ecological hypotheses, it is necessary that we understand, adapt, and use them in ways that both allow us to deliver their full potential and account for their limitations. Here, we attempt to increase the accessibility of network approaches by providing a review of the tools that have been developed so far, with – what we believe to be – their appropriate uses and potential limitations. This is not an exhaustive review of all methods and metrics, but rather, an overview of tools that are robust, informative, and ecologically sound. After providing a brief presentation of species interaction networks and how to build them in order to summarize ecological information of different types, we then classify methods and metrics by the types of ecological questions that they can be used to answer from global to local scales, including methods for hypothesis testing and future perspectives. Specifically, we show how the organization of species interactions in a community yields different network structures (e.g., more or less dense, modular or nested), how different measures can be used to describe and quantify these emerging structures, and how to compare communities based on these differences in structures. Within networks, we illustrate metrics that can be used to describe and compare the functional and dynamic roles of species based on their position in the network and the organization of their interactions as well as associated new methods to test the significance of these results. Lastly, we describe potential fruitful avenues for new methodological developments to address novel ecological questions.