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A low‐intervention approach to restoration that also allows restoration outcomes to be framed as trajectories of ecosystem change can be described as “open‐ended” restoration. It is an approach which recognizes that long‐term ecosystem behavior involves continual change at small and large spatial and temporal scales. There are a number of situations in which it is appropriate to adopt an open‐ended approach to restoration including: in remote and large areas, where ecological limiting factors will be changed by future climates, where antecedent conditions cannot be replicated, where there are novel starting points for restoration, where restoration relies strongly on processes outside the restoration area, in inherently dynamic systems, where costs are high and where the public demands “wildness.” Where this approach is adopted managers need to explain the project and deal with public expectations and public risk. Monitoring biotic and abiotic components of the project are very important as an open‐ended approach does not equate to “abandon and ignore it.”  相似文献   

4.
Accurate and ecologically meaningful characterisation of reference conditions is a fundamental premise of restoration ecology. Restoration practice and research commonly define reference conditions in terms of compositional and structural elements. We propose a “process-centred” framework that places central emphasis on ecological functions and ecosystem processes. A wide variety of processes is central to the functioning and dynamics of ecological systems, and can be placed at the foundation of restoration research and practice. A process-centred approach allows the definition of “reference dynamics”, where spatial and temporal variability and underlying mechanisms of change are primary. We illustrate this approach using a 303-yr reconstruction of the natural surface fire regime to guide restoration of a Pinus ponderosa forest in the Jemez Mountains of southwestern North America. Fire occurrence varied over space and time during the period of record, with ecologically significant variation in fire intervals (yr fire−1) governed by process–structure interactions. We defined a variety of reference variables for reintroduction of fire as the keystone ecological process, along with related structural variation. A process-centered approach and the reference dynamics paradigm can replace a more static concept of reference conditions in defining restoration baselines and provide an improved standard of comparison for restoration ecology.  相似文献   

5.
Understanding how plant community dynamics are impacted by altered disturbance regimes is a pressing challenge for restoration ecology. Most assessments of community dynamics involve computationally intensive statistical techniques, while management often defers to derived, qualitative “state‐and‐transition” models. Here, we demonstrate an intermediate approach to track and predict community resilience, diversifying the tools available to assess ecosystem change. First, we develop indices of sagebrush‐steppe community structure in permanent monitoring plots based on plant functional types and our conceptual understanding of the ecosystem. The indices define a bivariate space within which the trajectories of permanent monitoring plots can be tracked. Second, we quantify two metrics of community resilience: resistance (overall change during the time period) and stability (average amount of movement per monitoring period). Plots dominated by obligate seeder shrubs displayed low resilience relative to those dominated by grasses and forbs or resprouting shrubs. Resilience was strongly related to initial plant functional type composition and elevation. Our results suggest restoration objectives should consider how plant traits control ecosystem responses to disturbance. We suggest that the approach developed here can help assess longer‐term resilience, evaluate restoration success, and identify communities at risk of state transitions.  相似文献   

6.
Developing quantitative ecosystem–scale expectations of habitat restoration projects and examining trade‐offs associated with alternative approaches has been a challenge for restoration ecology. Many of the largest freshwater lake restoration projects have occurred in Florida to remediate degradation to vegetated littoral habitats resulting from stabilized water levels, but effects across lake food‐webs have not been assessed. We developed an ecosystem model using Ecopath with Ecosim and Ecospace for a generalized large, eutrophic Florida Lake to explore how simulated restoration activities could influence fish communities with emphasis on sport fish abundance. We modeled three habitat restoration scenarios: (1) “no control,” (2) a “10‐year control” that restored littoral habitat every 10 years, and (3) a “combined control” scenario that restored littoral habitat every 10 years with maintenance controls between 10‐year periods. Our “combined control” scenario provided the largest long‐term habitat restoration benefits for sport fish abundance and the fisheries they support. In Ecospace, we simulated a littoral habitat restoration project that reduced lake‐wide tussock coverage from 30 to 15%. Ecospace predicted positive benefits to sport fish and fisheries following the restoration simulation and highlighted the importance of habitat edge effects, spatial design of habitat restoration projects, and sampling designs for evaluating restoration projects.  相似文献   

7.
Meta-ecosystems: a theoretical framework for a spatial ecosystem ecology   总被引:4,自引:0,他引:4  
This contribution proposes the meta‐ecosystem concept as a natural extension of the metapopulation and metacommunity concepts. A meta‐ecosystem is defined as a set of ecosystems connected by spatial flows of energy, materials and organisms across ecosystem boundaries. This concept provides a powerful theoretical tool to understand the emergent properties that arise from spatial coupling of local ecosystems, such as global source–sink constraints, diversity–productivity patterns, stabilization of ecosystem processes and indirect interactions at landscape or regional scales. The meta‐ecosystem perspective thereby has the potential to integrate the perspectives of community and landscape ecology, to provide novel fundamental insights into the dynamics and functioning of ecosystems from local to global scales, and to increase our ability to predict the consequences of land‐use changes on biodiversity and the provision of ecosystem services to human societies.  相似文献   

8.
The spatial pattern of vegetation changes during ecological restoration, and these changes are affected by the process of restoration. The objective of this study was to integrate the pattern and mechanism of forest restoration in the Dinghushan Nature Reserve (DNR), Guangdong, China, based on data from remote sensing and long‐term field observations. We studied the pattern dynamics of three main forest types and their underlying mechanisms during restoration following a multiscale, hierarchical patch dynamics framework that integrates population, community, and landscape processes. Remote sensing data were used to determine the changes in landscape pattern during different periods of forest restoration from 1978 to 2006. At the landscape scale, the number, area, and perimeter of the needle/broad‐leaved mixed forest (MF) and the evergreen broad‐leaved forest (BF) increased, whereas those of the tropical needle‐leaved forest (NF) decreased during succession. Our analysis based on long‐term field observations indicated that the change rate of NF was lower than that of MF during 1981–1996, but became much higher during 1996–2007. The rate of change in landscape pattern and the progression of succession stages were consistent with each other. Our results also showed that species regeneration and community succession are the biological basis of forest landscape dynamics during vegetation restoration. Landscape pattern analysis allowed us to show “what” happened during vegetation restoration and “where,” and population and community analysis indicated “why” and “how” it happened.  相似文献   

9.
Valladares and Gianoli (2007) tried to answer a key question, “how much ecology do we need to know to restore Mediterranean ecosystems?” by focusing on (1) plant–plant interactions; (2) environmental heterogeneity and the potential adaptation of transplanted plants; and (3) phenotypic plasticity of the planted species. We consider their choice of topics incomplete and potentially misleading because (1) it is clearly biased toward a narrow set of research topics (phenotypic plasticity, facilitation, and climate change); (2) it assumes that active restoration, and specifically revegetation, is needed; and (3) it conveys a false perception that other basic ecological aspects of Mediterranean ecosystems are sufficiently known. Instead, we review the current knowledge on seed dispersal, succession, and ecosystem functioning for Mediterranean ecosystems. We argue that decades of research on these topics have yielded few practical guidelines for restoration, something that needs to be urgently corrected. First, the current “establishment limitation paradigm” for plant recruitment does not acknowledge the role of dispersal limitation at large spatial scales. More attention should be paid to nucleation processes and directed seed dispersal mediated by animals. Second, studies of vegetation dynamics and succession in the Mediterranean have led to an overly simplistic view of successional dynamics. How fast and deterministic succession is remains mostly unexplored; long‐term monitoring of successional dynamics at different spatial scales is urgently needed. Third, information on the functional status of Mediterranean ecosystems is required to identify processes hindering natural recovery after disturbances and to set priorities on the areas and ecosystem components to be restored.  相似文献   

10.
景观生态学与退化生态系统恢复   总被引:34,自引:5,他引:29  
退化生态系统的恢复是一项艰巨任务,它需要考虑到所要恢复的退化生态系统的结构,多样性和其动态的整体性和长期性。现在对于退化生态系统恢复研究已经要使生态学家们关注受损生态系统的理论和实际问题。退化生态系统恢复所面临的挑战是理解和利用生态演替理论来完成并加速恢复进程。恢复的主要目标是建立一个自维持的,由不同的群落或生态系统组成的能够满足不同需要如生物保护和粮食生产需要的景观。景观生态学关注于大的空间尺度的生态学问题。景观生态学研究方法可以为退化生态系统恢复实践提供指导。在解决退化生态系统的恢复问题时,景观生态学的方法在理论和实践上是有效的。景观生态学中的核心概念和其一般原理斑块形状、生态系统间相互作用、镶嵌系列等都同退化生态系统的恢复有着密切的关系。如恢复地点的选择和适当的恢复要素的空间配置。在评价退化生态系统的恢复是否取得成功,利用景观生态学也具有重要的意义。景观生态学理论如景观格局与景观异质性理论,干扰理论和尺度理论都能够指导退化生态系统的恢复实践。同样地,退化生态系统的恢复可以为景观生态学的研究提供非常恰当的实验场。寓景观生态学思想于退化生态系统恢复过程是一种新的有效途径。  相似文献   

11.
干扰与生态系统演替的空间分析   总被引:34,自引:1,他引:33  
演替不光是生态系统在时间序列上的替代过程,而且也是生态系统在空间上的动态演变。演替的空间属性有演替系列的格局、范围、尺度、演替方向和速率、稳定的程度、多样性、以及在自然和人为干扰下的恢复等。干扰破坏了生态系统的稳定性,形成生态系统结构和功能的破损,使生态系统处于一种过渡状态。但是干扰也是生态系统演替的外在驱动力,自然的和人为的干扰引起的生态系统的对称性破缺,推动了系统的进化和演变。外界因素作用于生态系统的干扰因子包含了很多种类,如火、风倒、洪水、病虫害、人类活动等。干扰的属性有范围、频度、季节、强度、损害度、返回时间和循环周期。讨论了这些干扰的类型和生态系统演替所具有空间的特征,并且介绍了干扰和生态系统演替空间分析常用的方法,如空间解绎和辨识、空间统计分析、空间格局分析和地理信息系统的空间分析、以及空间模拟。利用了一些典型的实例来深入阐明空间分析在干扰和生态系统演替中的应用。利用美国加利福尼亚北部火干扰的历史和空间分布的记录,进行了火干扰的空间分析的研究;用Spies等在美国俄勒冈州西部1972~1988年的多时段的变化的实例说明了收获干扰的影响;利用俄勒冈州东部山地的主要两个虫害(山地松树甲虫(Mountain Pine Beetle)和云杉蚜虫(Spruce Budworm))22a的数据分析了病虫害干扰的空间分布格局及其与海拔、温度、降水和植被类型的关系。在生态系统演替的空间分析方面,以美国俄勒冈州西部的历史和现实植被演替格局的分析为例,讨论了如何利用空间分析方法研究区域尺度生态系统的演替,同时比较了历史和现实植被的空间格局指数的变化;用两个实例来说明空间分析在辨识大陆和国家尺度生态系统变迁中的应用,一个是美国原生的老森林(Old~growth)植被从1620年到1920年,300a的空间格局变化,另外一个是加拿大植被从1600年到2000年,大约400a的空间分布变化。最后,对生态系统演替的空间分析的一些重要问题作了探讨,例如:空间分析可否帮助确定地带性顶极群落;如何将外貌与成分结合更好地识别生态系统演替的空间格局与演变趋势;以及如何利用空间分析研究由于人类活动干扰加剧所造成的生态系统自然演化规律的异化。  相似文献   

12.
Evans and Davis claim the SER Standards use a “pure naturalness” model for restoration baselines and exclude most cultural ecosystems from the ecological restoration paradigm. The SER Standards do neither. The SER Standards consider both “natural” ecosystems (that are unequivocally not cultural) and “similar” cultural ecosystems as suitable reference models. Furthermore, Evans and Davis propose assessing whether a cultural ecosystem exhibits “good, bad, or neutral impacts from humans on ecosystems” as the basis for reference models. We argue that such an approach would overlook the indispensability of native ecosystem benchmarks to measure human impacts and provide a springboard for social‐ecological restoration.  相似文献   

13.
区域生态安全格局:概念与理论基础   总被引:126,自引:13,他引:113  
提出区域生态安全格局概念的提出 ,适应了生态系统恢复和生物多样性保护的发展需求。针对区域生态环境问题 ,通过干扰排除以及空间格局规划和管理 ,能够保护和恢复生物多样性 ,维持生态系统结构、功能和过程的完整性 ,实现对区域生态环境问题的有效控制和持续改善。区域生态安全格局的研究对象具有针对性、研究尺度具有区域性、研究问题具有系统性、研究手段具有主动性。它强调区域尺度的生物多样性保护、退化生态系统恢复及其空间合理配置、生态系统健康的维持、景观生态格局的优化、以及对社会经济发展需求的满足。它更加强调格局与过程安全及其整体集成 ,将生态系统管理对策落实到具体的空间地域上 ,实现管理效果的直观可视。相关理论 ,景观生态学、干扰生态学、保护生物学、恢复生态学、生态经济学、生态伦理学、和复合生态系统理论等为其提供了坚实的理论基础。区域生态安全格局不存在一个固定标准 ,人类对生态系统服务功能需求的不断变化是生态系统管理的根本原因。实现区域生态安全不但要以社会、经济、文化、道德、法律、和法规为手段 ,更要以其不断发展对生态系统服务功能的新需求为目标逐步进行。区域生态安全格局研究对于解决区域生态环境问题具有不可替代的作用 ,具有广阔应用前景。  相似文献   

14.
Present State and Future Perspectives of Restoration Ecology—Introduction   总被引:1,自引:1,他引:0  
Although the aim of and the need for ecological restoration, and restoration ecology as its scientific base, are obvious, the field is still struggling with defining its basics. This situation, reflected by the debate about alternative terms to replace “restoration,” the ambiguous self‐image as a movement, art, application, or science, and the lack of a unifying conceptual framework, results in an uncertainty about the future development of the field. In a 10‐year project, an interdisciplinary Research Training Group in Jena followed the regeneration of one degraded terrestrial and aquatic ecosystem, respectively, and suggested a conceptual model for regeneration and restoration that was derived from the shared features of the two systems. As part of the scientific discussion of this new approach, an international workshop “Present State and Future Perspectives of Restoration Ecology” was organized in Jena in November 2004. The following collection of 12 opinion papers and 1 concluding chapter reflect the discussions at the workshop and contributes to the “self‐finding” process of restoration ecology.  相似文献   

15.
Extreme disturbance events denote another aspect of global environmental changes archetypal of the Anthropocene. These events of climatic or anthropic origin are challenging our perceived understanding about how forests respond to disturbance. I present a general framework of tropical forest responses to extreme disturbance events with specific examples from tropical dry forests. The linkage between level of disturbance severity and dominant mechanism of vegetation recovery is reflected on a variety of initial trajectories of forest succession. Accordingly, more realistic and cost‐effective restoration goals in many tropical forests likely consist in maintaining a mosaic of different successional trajectories while promoting landscape connectivity, rather than encouraging full‐ecosystem recovery to pre‐disturbance conditions. Incorporating extreme disturbance events into the global restoration ecology agenda will be essential to design well‐informed ecosystem management strategies in the coming decades.  相似文献   

16.
植物群落动态的模型分析   总被引:6,自引:0,他引:6  
植物群落的动态是植物群落学的中心问题之一,包括更新、波动、演替、进化等主要内容。空间格局对种群和群落的动态起着至关重要的作用,种群空间格局和群落空间结构是群落中各种过程相互作用的产物。模型是描述群落动态、认识植物群落组建和维持机理的有效工具。本文阐述和比较了描述群落动态的四种具有代表性的经验模型,即镶嵌循环模型、随意游走模型、同资源种团比例模型、空间抢先占有模型及其机理。四种经验模型的空间性及缺陷分别是:(1)“镶嵌循环模型”考虑到了相邻斑块之间的植被空间结合在群落动态中的作用,而另外三种模型没有考虑到这一点;(2)在一定程度上,四种植物群落动态模型对各自针对的植物群落可能是适合的,但要作为描述群落动态发展的一般性模型还需要不断完善和发展;因为四种模型均没有考虑到自然干扰和人类干扰对植物群落动态的影响。作者对将来植物群落动态的研究及实践意义做出以下展望:(1)在不同空间尺度上,更加有效地评价控制群落动态变化的各种过程的相对重要性,并进一步将它们之间的复杂相互作用整合到群落动态模型中;(2)充分认识植物群落中存在的各种自然环境条件和生物群体的结构配置对植物群落动态发展的重要性;(3)重视植物群落动态发展中自然干扰过程和人类干扰过程的整合以  相似文献   

17.
To bridge the gaps between restoration as a science and as a practice, restoration ecology has to broaden its scope toward transdisciplinarity in close cooperation with landscape ecologists and other holistic environmentally oriented scientists, professionals, practitioners, and stakeholders. For restoration, the ongoing transdisciplinary scientific revolution has opened new insights to cope with the complex bio‐hydro‐ and human‐ecological network relations. The Total Human Ecosystem (THE), integrating humans with all other organisms and their total environment at the highest level of the global hierarchy, should become the unifying holistic paradigm for all synthetic “eco‐disciplines.” These should link ecological knowledge, wisdom, and ethics with their scientific and professional expertise from the natural and social sciences and the humanities. As the tangible matrix for all organisms, including humans, our industrial Total Human Landscape is the concrete spatial and functional system of the THE. It forms a closely interlaced network of solar energy–powered natural and seminatural biosphere landscapes and fossil energy–powered urban and agro‐industrial technosphere landscapes. The self‐organizing and self‐creative restoration capacities of biosphere landscapes are driven by mutually amplifying auto‐ and cross‐catalytic feedback loops, but the rapidly expanding technosphere landscapes are driven by destabilizing “run‐away” feedback loops. To prevent a global breakdown and to ensure the sustainable future for both humankind and nature, these positive feedbacks have to be counteracted by restraining, cultural feedbacks of environmental planning and management, conservation, and restoration. As the theme of this special issue alludes to, this template should become an integral part of an urgently needed sustainability revolution, to which the transdisciplinary landscape restoration could contribute its important share.  相似文献   

18.
Ecosystem engineers are increasingly being reintroduced to restore ecological processes in restoration and rewilding projects. To predict and adaptively manage the impact of such species their behavioral ecology must be understood and quantified. Rooting behavior by wild boar qualifies them as ecosystem engineers due to their impact on vegetation disturbance regimes. The behavioral foraging ecology of wild boar was quantified in a fenced area in the Scottish Highlands in order to provide some of the understanding necessary to predict their ability to affect ecosystem restoration. Five wild boar were monitored within a 125 ha fenced area using Global Positioning System (GPS) collars and behavioral monitoring over a 12‐month period. Their activity budget, the relationship between foraging behavior and vegetation communities, and how these relationships vary between seasons was investigated. The results indicate that wild boar invested approximately four more hours daily to rooting during the autumn and winter than the spring and summer. During the spring and summer, grazing was the dominant foraging behavior (approximately 28% of foraging period) while rooting dominated in autumn and winter (approximately 76% of foraging period). Deep rooting behavior is particularly associated with bracken‐dominated communities. Associations between rooting, vegetation community, and season will have a strong influence on the spatial and temporal distribution of rooting behavior. This variation could have important implications for the impacts of boar on vegetation community dynamics. These results detail some of wild boar's ecosystem engineering behaviors; however, further research is required to consider the wider impacts of a full reintroduction.  相似文献   

19.
恢复生态学研究的一些基本问题探讨   总被引:193,自引:13,他引:180  
对恢复生态学的研究概况、基本概念、内涵与研究内容以及生态恢复的目标、原则、程序与技术进行了分析与探讨。指出恢复生态学应加强基础理论研究(包括生态系统的演替理论及干扰条件下生态系统的受损过程与响应机制研究等)和应用技术研究(包括土壤、水体、大气和植被恢复技术、生物多样性保护技术以及生态系统的组装与集成技术等).生态恢复与重建是指根据生态学原理,通过一定的生物、生态以及工程的技术,人为地切断生态系统退化的主导因子和过程,调整和优化系统内部及其与外界的物质、能量和信息的流动过程及其时空秩序,使生态系统的结构、功能和生态学潜力尽快地成功地恢复到原有的乃至更高的水平。  相似文献   

20.
The concept of life‐history traits and the study of these traits are the hallmark of population biology. Acknowledging their variability and evolution has allowed us to understand how species adapt in response to their environment. The same traits are also involved in how species alter ecosystems and shape their dynamics and functioning. Some theories, such as the metabolic theory of ecology, ecological stoichiometry or pace‐of‐life theory, already recognize this junction, but only do so in an implicitly non‐spatial context. Meanwhile, for a decade now, it has been argued that ecosystem properties have to be understood at a larger scale using meta‐ecosystem theory because source–sink dynamics, community assembly and ecosystem stability are all modified by spatial structure. Here, we argue that some ecosystem properties can be linked to a single life‐history trait, dispersal, i.e. the tendency of organisms to live, compete and reproduce away from their birth place. By articulating recent theoretical and empirical studies linking ecosystem functioning and dynamics to species dispersal, we aim to highlight both the known connections between life‐history traits and ecosystem properties and the unknown areas, which deserve further empirical and theoretical developments.  相似文献   

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