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1.
1. Most Finnish streams were channelised during the 19th and 20th century to facilitate timber floating. By the late 1970s, extensive programmes were initiated to restore these degraded streams. The responses of fish populations to restoration have been little studied, however, and monitoring of other stream biota has been negligible. In this paper, we review results from a set of studies on the effects of stream restoration on habitat structure, brown trout populations, benthic macroinvertebrates and leaf retention. 2. In general, restoration greatly increased stream bed heterogeneity. The cover of mosses in channelised streams was close to that of unmodified reference sites, but after restoration moss cover declined to one‐tenth of the pre‐restoration value. 3. In one stream, densities of age‐0 trout were slightly lower after restoration, but the difference to an unmodified reference stream was non‐significant, indicating no effect of restoration. In another stream, trout density increased after restoration, indicating a weakly positive response. The overall weak response of trout to habitat manipulations probably relates to the fact that restoration did not increase the amount of pools, a key winter habitat for salmonids. 4. Benthic invertebrate community composition was more variable in streams restored 4–6 years before sampling than in unmodified reference streams or streams restored 8 years before sampling. Channelised streams supported a distinctive set of indicator species, most of which were filter‐feeders or scrapers, while most of the indicators in streams restored 8 years before sampling were shredders. 5. Leaf retentiveness in reference streams was high, with 60–70% of experimentally released leaves being retained within 50 m. Channelised streams were poorly retentive (c. 10% of leaves retained), and the increase in retention following restoration was modest (+14% on average). Aquatic mosses were a key retentive feature in both channelised and natural streams, but their cover was drastically reduced through restoration. 6. Mitigation of the detrimental impacts of forestry (e.g. removal of mature riparian forests) is a major challenge to the management of boreal streams. This goal cannot be achieved by focusing efforts only on restoration of physical structures in stream channels, but also requires conservation and ecologically sound management of riparian forests.  相似文献   

2.
River ecosystems face growing threats from human-induced stressors, resulting in habitat degradation and biodiversity loss. Crucial to these ecosystems, macroinvertebrates maintain river health and functioning. In this review, we examine the challenges confronting macroinvertebrates, explore restoration strategies and management approaches, and shed light on knowledge gaps and future research directions. Habitat degradation, water pollution, climate change, and invasive species are discussed as key challenges. Various restoration strategies, such as in-stream habitat restoration, flow regime restoration, riparian zone restoration, and connectivity restoration, are evaluated for macroinvertebrate conservation. Integrated catchment management, adaptive management, community-based management, monitoring, and policy integration are highlighted as essential management approaches, and knowledge gaps in long-term monitoring, innovative restoration techniques, climate change resilience, and policy incorporation are identified as areas calling for further research. Ultimately, a proactive, adaptable, and cooperative approach to river management will ensure macroinvertebrate conservation and sustainable river ecosystems.  相似文献   

3.
张立斌  杨红生 《生命科学》2012,(9):1062-1069
由于人类活动导致的海洋生境、生态系统以及生物资源的衰退已经引起了全球的高度重视。以生态修复的原理为基础,综述了海洋生境修复和生物资源养护的关键设施、关键技术、监测与效果评价以及综合管理的国内外研究进展,并对海洋生境修复与生物资源养护的研究热点和重点进行了展望,以期为我国海洋生境修复和生物资源养护提供参考。  相似文献   

4.
The loss and fragmentation of habitat is a major threat to the continued survival of many species. We argue that, by including spatial processes in restoration management plans, the effects of habitat loss and fragmentation can be offset. Yet few management plans take into account spatial effects of habitat conservation/restoration despite the importance of spatial dynamics in species conservation and recovery plans. Tilman et al. (1997) found a “restoration lag” in simulations of species restoration when randomly selecting habitat for restoration. Other studies have suggested that the placement of restored habitat can overcome effects of habitat loss and fragmentation. Here we report the findings of simulations that examine different regional management strategies, focusing on habitat selection. We find that nonrandom restoration practices such as restoring only habitat that is adjacent to those occupied by the target species can dramatically reduce or negate any restoration lag. In fact, we find that the increase in patch occupancy of the landscape can be greater than two-fold in the adjacent versus the random scenarios after only two restoration events, and this increase can be as great as six-fold during the early restoration phase. Many restoration efforts have limitations on both funds and available sites for restoration, necessitating high potential success on any restoration efforts. The incorporation of spatial analyses in restoration management may drastically improve a species' chance of recovery. Therefore, general principles that incorporate spatial processes and sensible management are needed to guide specific restoration efforts.  相似文献   

5.
Rivers are conduits for materials and energy; this, the frequent and intense disturbances that these systems experience, and their narrow, linear nature, create problems for conservation of biodiversity and ecosystem functioning in the face of increasing human influence. In most parts of the world, riparian zones are highly modified. Changes caused by alien plants — or environmental changes that facilitate shifts in dominance creating novel ecosystems — are often important agents of perturbation in these systems. Many restoration projects are underway. Objective frameworks based on an understanding of biogeographical processes at different spatial scales (reach, segment, catchment), the specific relationships between invasive plants and resilience and ecosystem functioning, and realistic endpoints are needed to guide sustainable restoration initiatives. This paper examines the biogeography and the determinants of composition and structure of riparian vegetation in temperate and subtropical regions and conceptualizes the components of resilience in these systems. We consider changes to structure and functioning caused by, or associated with, alien plant invasions, in particular those that lead to breached abiotic‐ or biotic thresholds. These pose challenges when formulating restoration programmes. Pervasive and escalating human‐mediated changes to multiple factors and at a range of scales in riparian environments demand innovative and pragmatic approaches to restoration. The application of a new framework accommodating such complexity is demonstrated with reference to a hypothetical riparian ecosystem under three scenarios: (1) system unaffected by invasive plants; (2) system initially uninvaded, but with flood‐generated incursion of alien plants and escalating invasion‐driven alteration; and (3) system affected by both invasions and engineering interventions. The scheme has been used to derive a decision‐making framework for restoring riparian zones in South Africa and could guide similar initiatives in other parts of the world.  相似文献   

6.
陈妍  周妍  包岩峰  周旭  苏香燕 《生态学报》2023,43(21):8894-8902
我国实施了诸多生态保护修复工程,取得了显著成效。然而,以往工程多以湿地、森林、草原等单一类型的生态系统为保护修复目标,缺乏区域整体性、系统性考虑。2016年以来,我国开始从完整流域的视角出发,系统考虑生态系统完整性、自然地理单元连续性和社会经济可持续性,实施山水林田湖草沙一体化保护和修复工程。该类工程保护修复目标多样、内容庞杂,因而成效评估面临子项目类型多、空间尺度多、目标维度多、项目实施周期短等诸多挑战。就空间尺度而言,评估对象既要涵盖常规评估中相对较大的、确定的空间范围,也要涵盖具有相对类似生态问题或目标的保护修复单元,以及实际采取措施的子项目;就时间尺度而言,既要考虑工程实施结束时的成效,也要考虑实施结束后的成效动态;就评估内容而言,既要关注社会、生态、经济效益,也要考察工程措施与生态效应之间的关系、不同类型子项目的关联性与协同性、工程的整体性与系统性。研究基于上述背景制定了一个新型评估框架,重点强调基于子项目、保护修复单元以及工程范围三个尺度的指标体系,以及生态、社会、经济、管理四个方面的评估内容。新的评估框架将有助于完善山水林田湖草沙一体化保护和修复工程标准体系,为推进国土空...  相似文献   

7.
Ecological restoration of forest ecosystems is increasingly being implemented in many parts of the world, as a response to widespread forest loss and degradation. In common with other conservation management interventions, restoration efforts should be directed towards areas where the maximum benefits are likely to be achieved. Such prioritisation requires the development of appropriate criteria and indicators (C&I), an issue poorly addressed by previous research. In particular, there is need for C&I that are operational, suitable for spatial analysis and mapping and applicable to a broad range of contexts. This investigation aimed to verify whether this might be achieved through the elicitation of experts’ opinion, when considering biodiversity conservation as the main objective of restoration. A Delphi process was performed, aimed at defining the key ecological criteria and a broad set of indicators. 389 criteria and 669 related indicators were provided in total and grouped into clusters relating to individual criteria. A total of 20 criteria referred to the need for restoration and 18 to its feasibility. In the second round of the Delphi process, 8 definitive criteria were identified along with some 90 related indicators. Finally, a face-to-face meeting was conducted to show how ready-to-use C&I can be obtained for application to a specific context starting from the Delphi's results. The study highlights the potential value of combining the Delphi process and face-to-face meetings for identifying practically applicable C&I for planning ecological restoration. However, the diversity of views identified within a single group of stakeholders suggests that the development of a generally applicable set of C&I for forest restoration will be difficult to achieve in practice.  相似文献   

8.
Human–wildlife conflict (HWC) has become a conservation focus for both protected area management and local communities in many parts of the world. The incidence and mediation of HWCs are rooted in coupled environmental and socioeconomic contexts. A systematic analysis of HWCs was undertaken in 2016 in the Wolong Nature Reserve located in Sichuan Province, southwestern China. Semi‐structured interviews were conducted with 201 local households to understand the occurrence of wildlife damage, the wildlife species involved, the typical losses incurred, and the mitigation measures employed. The results revealed that local HWC has increased rapidly in recent years due to effective biodiversity conservation and ecological restoration policies. Despite the widespread occurrence of HWCs, with nearly all respondents stating that they had suffered a financial loss, appropriate compensation schemes are lacking. Local respondents' expected compensation amount and style were investigated, and it was concluded that integrated compensation and community development plans are needed to mediate and resolve HWC. In particular, greater attention should be given to reduce local households' dependence on agriculture and transform local livelihood strategies to alternative economic activities not related to farming, such as ecotourism development and migrating employment.  相似文献   

9.
Abstract. This Special Feature focuses on lowland fens and flood plains. In this introduction we discuss the most important mire‐related terms, present status, threats and conservation and restoration attempts. Floodplains and especially lowland fens are rare and vulnerable ecosystems. They are highly threatened all over the world because of direct conversion to agricultural land and especially the lack of appropriate management and altered catchment hydrology. Finally we present a framework for the conservation and restoration of these ecosystems. This consists of (1) optimising abiotic conditions; (2) safeguarding propagule availability of the target species; (3) creating and maintaining conditions for (re)establishment of these species, and (4) appropriate management to keep the conditions suitable.  相似文献   

10.
Conservation and restoration interventions can be mutually reinforcing and are converging through an increased focus on social dimensions. This paper examines how to more effectively integrate the complementary goals of conservation and restoration of tropical forests. Forest conservation and restoration interventions are integral components of a broad approach to forest ecosystem and landscape management that aims to maintain and restore key ecological processes and enhance human well‐being, while minimizing biodiversity loss. The forest transition model provides a useful framework for understanding the relative importance of forest conservation and restoration interventions in different regions. Harmonizing conservation and restoration presents serious challenges for forest policy in tropical countries, particularly regarding the use and management of secondary forests, fallow vegetation, and forests degraded by logging and fire. Research to implement restoration more effectively in tropical regions can be stimulated by transforming questions that initially focused on conservation issues. Examination of papers published in Biotropica from 2000–2018 shows that most studies relevant to tropical forest conservation do not address forest restoration issues. Forest restoration studies, on the other hand, show a consistent association with conservation issues. There is much scope for further integration of conservation and restoration in research, practice, and policy. Securing a sustainable future for tropical forests requires developing and applying integrated approaches to landscape management that effectively combine knowledge and tools from multiple disciplines with practical experience and engagement of local stakeholders. Abstract in Portuguese is available with online material.  相似文献   

11.
Restoration models and practise to date have been applied mainly to ecosystems. More recently, there has been a focus on the “landscape perspective” of ecosystem restoration in order to improve nature conservation and management effectiveness.

Here, we clarify some of the differences between ecosystem- and landscape-oriented restoration, and propose four components that should be considered in planning and conceptualising: (a) landscape composition and configuration; (b) traditional land management techniques; (c) linear and point features; and (d) other heritage features. We further discuss the concept of reference landscapes, and the contrasts between restoration and rehabilitation. Spatial approaches to restoration are explored, comparing small areas with complete restoration (“museum landscapes”) from large areas with rehabilitation of landscape physiognomy or point and linear features. The linkages with nature conservation and the sustainable use and management of natural resources are examined in the context of a rapidly changing world.  相似文献   


12.
黄土高原水土流失治理现状、问题及对策   总被引:19,自引:0,他引:19  
黄土高原位于黄河中游地区,是世界上水土流失最为严重的区域之一;黄土高原水土流失治理问题历来受到国家高度关注,涌现了种类多样的水土流失治理模式,目前还缺乏对黄土高原区域尺度水土流失治理模式的总结和整理。本文总结和整理了建国以来黄土高原主要的四类水土流失治理模式,生物措施模式主要由退耕还林、荒山造林和封山育林工程组成,工程措施模式包括修建梯田和淤地坝,以及近期涌现的治沟造地工程;小流域综合治理模式主要体现在坡面、沟道系统整治,生物和工程措施相结合的特点,区域综合整理模式则强调对生态系统进行整体保护、系统修复和综合治理,达到生态、社会、经济可持续发展。基于黄土高原水土流失治理模式存在的问题,提出了黄土高原水土流失治理模式调整和优化建议,以期对黄土高原生态恢复建设和水土流失科学治理提供科学依据。  相似文献   

13.
This paper is based on research of the restoration of species‐rich calcareous grasslands in The Netherlands, over the last 30 years. Chalk grassland is a semi‐natural vegetation with a high density of species at a small scale. This type of vegetation was once widespread in Western Europe as common grazing land, mainly for flocks of sheep for which the main function was dung production. In some regions of Central Europe, these grasslands were also used for hay production. The dung was used to maintain arable field production at a reasonable level. In the chalk district in the southernmost part of The Netherlands some 25 sites of this vegetation, varying in area from 0.05–4.5 ha, are still present. Chalk grassland completely lost its significance for modern agricultural production after the wide application of artificial fertilizer following World War II. This grassland has a high conservation value both for plants and animal species, of which a large number of species are exclusively restricted to this biotope. When conservation activities started at a large scale in the early 1960s, three different types of restoration activities could be distinguished: (1) restoration of fertilized sites; (2) restoration of abandoned grasslands; and (3) recreation of chalk grassland on former arable fields. The main aim of the restoration attempt is to create and/or improve sustainable conditions for both plant and animal species characteristic of the chalk grassland ecosystem. In the process of restoration, several phases of different activities can be distinguished: (1) pre‐restoration phase, during which information of the land use history is collected and, based on these data, clear restoration goals are established; (2) initial restoration phase, during which effects of former, non‐conservational land use has to be undone in order to stimulate germination and establishment of target species originating from soil seed bank and species pool; (3) consolidation phase, including the introduction and continuation of a regular management system for sustainable conservation; and (4) long‐term conservation strategy, including measures to prevent disturbance from the outside and genetic erosion and extinction of locally endangered plant populations.  相似文献   

14.
In highly impaired watersheds, it is critical to identify both areas with desirable habitat as conservation zones and impaired areas with the highest likelihood of improvement as restoration zones. We present how detailed riparian vegetation mapping can be used to prioritize conservation and restoration sites within a riparian and instream habitat restoration program targeting 3 native fish species on the San Rafael River, a desert river in southeastern Utah, United States. We classified vegetation using a combination of object‐based image analysis (OBIA) on high‐resolution (0.5 m), multispectral, satellite imagery with oblique aerial photography and field‐based data collection. The OBIA approach is objective, repeatable, and applicable to large areas. The overall accuracy of the classification was 80% (Cohen's κ = 0.77). We used this high‐resolution vegetation classification alongside existing data on habitat condition and aquatic species' distributions to identify reaches' conservation value and restoration potential to guide management actions. Specifically, cottonwood (Populus fremontii) and tamarisk (Tamarix ramosissima) density layers helped to establish broad restoration and conservation reach classes. The high‐resolution vegetation mapping precisely identified individual cottonwood trees and tamarisk thickets, which were used to determine specific locations for restoration activities such as beaver dam analogue structures in cottonwood restoration areas, or strategic tamarisk removal in high‐density tamarisk sites. The site prioritization method presented here is effective for planning large‐scale river restoration and is transferable to other desert river systems elsewhere in the world.  相似文献   

15.
I consider the possibility that people engaged in conservation and management of species and ecosystems are experiencing grief related to ongoing loss of species, assemblages, ecosystem integrity, and so on. In human psychology, five stages of the grieving process have been identified, namely denial, anger, bargaining, depression, and acceptance. Although presented as a series of stages, it is recognized that the progression through them is not linear and people can move quickly among them or experience more than one at any one time. I then consider whether current polarized debates in conservation and restoration, for instance in relation to non‐native species and novel ecosystems, result in part from people operating from different places in the grief spectrum. Throughout the grieving process, hope remains a constant feature, and it is important to recognize the place of hope in motivating and sustaining people engaged in conservation and restoration. Although restoration provides great hope that losses can be minimized and, in some cases, reversed, this hope needs to be grounded in a realistic assessment of what is possible in a rapidly changing world.  相似文献   

16.
东苕溪中下游河岸类型对鱼类多样性的影响   总被引:2,自引:0,他引:2  
河流修复工程被美国《科学》杂志列入2000年最具发展潜力的六大领域之一,河流修复工程对水生生态系统的影响也成为各国科学家的研究热点。本文以东苕溪中下游河段为对象,研究4种不同河岸类型(自然河岸 水生植物(A)、自然河岸 无水生植物(B)、人工河岸 水生植物(C)、人工河岸 无水生植物(D))对鱼类生物多样性的影响。本次调查共采集鱼类标本499尾,经鉴定为32种,隶属于7目10科24属。鱼类生物多样性结果显示A、B的物种丰度和Shannon-Wiener指数与D存在显著差异(P<0.05); A的优势度指数与D存在显著性差异(P<0.05); A、C的均匀度与D存在显著性差异。鱼类群落NMDS排序与相似性分析(ANOSIM)显示D与A、B、C能完全分开,且D与A、C存在显著性差异(P<0.05),其中A与C存在显著性差异。因此,河流修复工程中水生植被的恢复对于水生生物多样性的维持至关重要,且恢复水生植被的河流修复工程会减少该工程对鱼类群落结构和生物多样的负面影响。  相似文献   

17.
朱青  周自翔  刘婷  白继洲 《生态学报》2021,41(7):2557-2570
为探究黄土高原地区退耕还林(草)工程(1999)实施后植被恢复的生态效益,选择黄土高原延河流域为研究区,利用趋势线分析法、SWAT(Soil and Water Assessment Tool)水文模型和生态系统服务价值评价方法(市场价值法、机会成本法、恢复费用法和影子工程法等),重点分析2000-2015年该区域植被恢复状况及其对土壤保持的作用,并评估生态系统服务价值的提升效应。研究结果表明:(1)退耕还林(草)工程实施后,延河流域植被覆盖均呈增加趋势,植被恢复显著;(2)植被恢复对土壤侵蚀的抑制作用明显。在没有植被覆盖的条件下,土壤极易发生侵蚀,且侵蚀模数大;从该工程实施以来,2001-2014年土壤保持量具有不同程度的增幅,表明多年来流域治理取得一定的成效;(3)流域植被覆盖以中覆盖为主,土壤保持量以低保持为主。不同植被覆盖下土壤保持量存在差异。其中,中低、中、中高覆盖能有效保持土壤;(4)生态系统土壤保持服务价值时空分布特征明显。流域年均(2000-2015)土壤保持服务价值为3.64×108元,生长季月均土壤保持服务价值为6.06×107元,生态系统土壤保持服务价值显著提升。时间尺度上,生态系统土壤保持服务价值受降水因素影响;空间尺度上,流域生态系统土壤保持服务价值空间差异大,具体表现为下游残塬平梁沟壑区最高,上游山地区次之,中游梁峁丘陵沟壑区最低。通过研究延河流域植被恢复状况以及定量评估土壤保持服务价值,不仅阐明了退耕还林(草)工程带来的巨大生态效益,同时也为流域乃至黄土高原的水土流失治理工作提供一定的参考作用。  相似文献   

18.
Despite the growing body of literature on ecosystem services, still many challenges remain to structurally integrate ecosystem services in landscape planning, management and design. This paper therefore aims to provide an overview of the challenges involved in applying ecosystem service assessment and valuation to environmental management and discuss some solutions to come to a comprehensive and practical framework.First the issue of defining and classifying ecosystem services is discussed followed by approaches to quantify and value ecosystem services. The main part of the paper is focussed on the question how to analyze trade-offs involved in land cover and land use change, including spatial analysis and dynamic modelling tools. Issues of scale are addressed, as well as the question how to determine the total economic value of different management states.Finally, developments and challenges regarding the inclusion of ecosystem services in integrative landscape planning and decision-making tools are discussed.It is concluded that the ecosystem service approach and ecosystem service valuation efforts have changed the terms of discussion on nature conservation, natural resource management, and other areas of public policy. It is now widely recognized that nature conservation and conservation management strategies do not necessarily pose a trade-off between the “environment” and “development”. Investments in conservation, restoration and sustainable ecosystem use are increasingly seen as a “win-win situation” which generates substantial ecological, social and economic benefits.  相似文献   

19.
Aims In this paper, we highlighted some key progresses in mangrove conservation, restoration and research in China during last two decades.Methods Based on intensive literature review, we compared the distribution and areas of existing mangroves among selected provinces of China, discussed the issues associated with mangrove conservation and restoration and highlighted major progresses on mangrove research conducted by key institutions or universities in mainland China, Hong Kong, Taiwan and Macao.Important findings The population boom and rapid economic developments have greatly reduced mangrove areas in China since 1980s, leaving only 22?700 ha mangroves in mainland China in 2001. Chinese government has launched a series of programs to protect mangroves since 1980s and has established mangrove ecosystems as high-priority areas for improving environmental and living resource management. During last three decades, a total of 34 natural mangrove conservation areas have been established, which accounts for 80% of the total existing mangroves areas in China. Mangrove restoration areas in Mainland China accounted for <7% of the total mangroves areas in 2002. A great deal of research papers on Chinese mangroves has been published in international journals. However, more systematic protection strategies and active restoration measurements are still urgently needed in order to preserve these valuable resources in China.  相似文献   

20.
The conservation of dry calcareous grasslands in the French Prealps strongly depends on the maintenance of low-intensity farming systems supported by agri-environmental schemes. An experimental assessment of the effect of current agro-pastoral management on the biodiversity of plant communities was conducted during a six-year permanent plot survey in four sites with contrasting habitat conditions (mesic to xeric). Analyses of species changes showed: (i) a strong increase in species richness and open grassland species frequencies four years after shrub-clearing, and (ii) a noticeable recovery of rare annuals and perennial species of conservation interest establishing in gaps created by grazing. At the community level, the restoration effect was evaluated by a between-year Correspondence Analysis, explaining 10.9% of the total floristic variability versus 29.5% for the site effect (between-site CA). Species ordination by between-year CA showed similar trajectories of vegetation changes during restoration despite different habitat conditions and grazing regimes between sites. The successful restoration of prealpine calcareous grasslands was explained by the availability of seed sources during the study in adjacent grazed or mown grasslands. Thus, restoration assessment should focus on dispersal possibilities and functional roles of species rather than species richness only. Finally, the spatial (i.e. the area of patches that need to be restored) and temporal (i.e. the frequency of shrub-clearing) implications for the large-scale conservation of prealpine calcareous grasslands by current agro-pastoral management are discussed.  相似文献   

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