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1.
Management of private land for ecological outcomes has emerged as an important facet of biodiversity management and ecological restoration in Australia. Common law conservation contracts and conservation covenants are important tools within this framework of private land conservation. They can provide legal protections to biodiversity and natural assets on private land, as well as legal frameworks, in the form of obligations, to restoration programs. They can provide distinct qualities of binding obligation: fixed term or enduring. Conservation contracts and covenants need to be recognized as possessing both transactional and relational qualities, and these qualities should be considered and reflected in the design of agreements and in practices of conservation management and agreement‐making. Two design questions are considered in this article. Conservation agreements need to contend with dynamism in ecological and social realities and this may be accommodated in mechanisms for adjustment of obligations between or within agreements. Dispute management is a second field of practice and drafting requiring attention. Constructing disputes provisions that are adapted and appropriate to long‐term conservation actions and restoration initiatives is reflective of good faith principles and can include scope for graduated, independent, corrective, and fair arrangements, informed as necessary by expert input.  相似文献   

2.
<Abstract>

Earlier studies suggested that the Mesovoid Shallow Substratum (MSS), a subterranean network of voids immediately under the soil and scree horizon, might play an important role in the life cycle of some troglobitic species. No ecological studies have been conducted to test whether this terrestrial shallow subterranean habitat only plays an important role for a few subterranean or preferential species, or whether it is also important for the soil faunal structure and dynamics. We investigated the spatial and temporal patterns of the arthropod community in the MSS and sub-alpine scree and analysed the correlations with environmental variables. We identified 140 soil-dwelling, characteristic and troglobitic species that inhabited the MSS in different seasonal assemblages. Combined statistical analyses of the environmental factors and seasonal variation in arthropod abundance and biomass emphasized the importance of the MSS as an ecological microrefuge for many soil-dwelling species (including important predators and detritivores) which usually live in the adjacent forests or mountain pastures. Conservation plans for invertebrates should include the protection of the MSS.  相似文献   

3.
The distribution of wintering waterbirds within some Tunisian artificial wetlands (AW) was studied during the 2004–2007 stable wintering periods. The survey has regarded 88 wetlands including 27 large dams, 25 hill dams and 36 hill lakes. We identified 42,840 individuals representing seven orders, eleven families, 37 species and six functional groups: dabbling ducks, grazing waterfowl, fish‐eaters, deep‐water foragers, shoreline foragers and waders. The population structure analysis showed an absolute dominance of the deep‐water foragers with approximately 82% of observed waterbirds. The total abundance survey showed a fluctuation of population sizes and richness, from thousands to few individuals and from 1 to 25 species, respectively. Analysis results showed that the species distribution is governed by several ecological factors and there was a significant correlation between species abundance and richness and some habitat variables such as area, depth, age, plant cover and hunting disturbance. Investigated AW revealed a significant carrying capacity and refuge serving for the conservation of numerous wintering and endangered waterbird species of high nature conservation value, the White‐headed Duck Oxyura leucocephala that has been observed with relatively high numbers representing more than 40% of the assessed Tunisian–Algerian population.  相似文献   

4.
This study is focused on determining the response behaviour of five saline plant communities to two environmental variables: flooding and salinity. Also, total soil organic carbon, diversity, plant cover and vegetation height were measured. Once this behaviour is known, the impacts of future climate scenarios may be approached. Since some of these variables could be altered by climate change, the future vegetation dynamics might indicate the trending of change, so plant communities can be used as bioindicators. The investigation was carried out in some small coastal wetlands located in a semiarid Mediterranean region. Low values of diversity were found in these plant communities due to a great effect of flooding, followed by salinity. ‘Reed beds’ are bioindicators of flooding and environmental disturbance. ‘Saline rushes’ are also flooding bioindicators and efficient accumulators of organic matter. ‘Mediterranean halophilous scrubs’ are bioindicators of seasonal flooding and changes to salinity. ‘Mediterranean halo-nitrophilous scrubs’ might be considered as bioindicators of low flooding and low salinity in anthropic environment while ‘Mediterranean salt steppes’ bioindicate driest conditions. At present, Mediterranean halophilous scrubs are the most widely extended community, which could be interpreted as a consequence of a changing and sharply seasonal climate. Our research suggests that future climate change scenarios involving flooding increases would support the proliferation of the lowest diversity and thus lower ecological value plant communities (i.e. reed beds). Conversely, a future scenario of decreasing flooding would benefit the most diverse and valuable conservation community actually priortized by European Habitats Directive (Mediterranean salt steppes, Limonietalia).  相似文献   

5.
As biodiversity declines, wildlife conservation focuses on in situ and ex situ management strategies. Zoo-based breeding programmes are often designed to contribute to the conservation of species that are threatened in the wild. Diet contributes to the reproductive success, disease status and longevity of all animals. It is near-impossible to replicate a species' diet in captivity using only the species they consume in the wild, but the nutritional composition of a wild diet, if known, can be closely matched using commercially available foods for which the nutritional composition has been calculated. Ecological research has identified food items of importance in the diet of many species. However, the nutritional composition of these food items is rarely evaluated, even though the composition of wild food items is important in understanding the dietary adaptations and requirements of wildlife. In contrast, the nutritional requirements of domestic species are well researched and can be used to predict a range of plausible nutrient requirements of some wild species, especially those with similar life histories. Access to wild populations provides further opportunities for nutritional science to determine the requirements of individual species. Small-scale dietary experimentation undertaken at conservation institutions may show positive effects on health and welfare but is rarely published in the scientific literature. This review describes current standards in nutritional management of birds and recommends pathways for filling knowledge gaps. Research on mammals has dominated the nutrition literature, so there is a relative lack of nutritional management information for birds. We combine concepts of domestic animal nutrition with recent findings on the nutritional requirements of birds to provide a foundation for further studies of avian nutrition. We call for the broader zoological community to share data and collaborate on nutritional research to support conservation institutions in nutritional management of wild birds.  相似文献   

6.
青藏高原是我国重要的生态屏障。自然保护区能有效地保护生态安全和生物多样性, 评估自然保护区管理能力对保护成效的影响有利于自然保护区的科学保护与管理。本研究分析了青藏高原54处国家级自然保护区管理机构类型、资金、人员配置等管理能力方面的差异, 并利用归一化植被指数(normalized difference vegetation index, NDVI)研究不同自然保护区的保护成效, 揭示青藏高原国家级自然保护区管理能力与保护成效的关系, 为提升青藏高原自然保护区保护和管理成效提供依据。结果表明: (1)青藏高原国家级自然保护区管理机构行政级别差异较大, 包括厅局级(1处)、县处级(36处)、乡科级(16处)和股级(1处) 4个级别, 其中独立管理机构42处, 与其他机构合署办公的非独立管理机构12处, 行政级别和独立性影响保护成效, 行政级别较高、独立的管理机构的自然保护区保护成效较好。(2)青藏高原国家级自然保护区在单位管理资金、人均管理面积与巡护面积等方面与全国平均水平差异较大, 且专业人才普遍缺乏。建议重点关注青藏高原地区自然保护区保护管理的特殊性, 规范管理机构建设, 加强资金保障, 推动更多高水平专业人才从事保护工作, 进一步加大生态管护岗位设置与培训, 切实提高青藏高原地区自然保护区管理能力和保护成效。  相似文献   

7.
Europe's five species ofMaculinea butterfly are examples of endangered species adapted to live in traditional, cultural landscapes. All are threatened with extinction in Western Europe because of recent changes in land use. This is illustrated by an historical account of the extinction of the BritishMaculinea arion populations, despite many conservation attempts. It is shown how the failures proved to be due to ignorance of the key factor forM. arion, its specialization on a single ant host,Myrmica sabuleti. A brief account is given of research that shows how each of the five species is similarly dependent upon a separate hostMyrmica ant species and how each has an interesting and rare specific parasitoid. Steps for the practical conservation of existingMaculinea populations including the obligation, under the Bern Convention, to re-establish nationally extinct species are outlined. The procedure and problems involved in re-establishment are illustrated with reference to the successful programme forM. arion in Britain. The best way of ensuring robust populations ofMaculinea butterflies is to manage habitats to optimize the density and distribution of the required species ofMyrmica host and, secondarily, the distribution of the larval food plant. The value of single species conservation in cultural habitats is discussed. It is concluded that this is possible to achieve and that other rare organisms also often benefit, but only when conservation measures are based on the results of detailed autecological research.  相似文献   

8.
  • 1 Dolphins and porpoises in coastal and/or riverine habitats face serious conservation threats, yet surveys of their abundance are often especially difficult due to the challenges imposed by the habitats. Because many of these species occur in developing countries, lack of resources imposes a further set of challenges.
  • 2 We offer advice on designing and conducting line‐transect surveys with a focus on sound, practical, design rather than analytical sophistication, and we attempt, where possible, to offer simple, inexpensive solutions.
  • 3 We guide the reader through the questions of what kind of survey should be done, whether by boat or aircraft, and we discuss ways to avoid bias and increase precision.
  • 4 Our treatment of field methods focuses especially on robust, but low‐cost, approaches. We provide two case studies to illustrate the implementation of these ideas.
  相似文献   

9.
An official organization responsible for ecological research and nature conservation was formed in 1949. This paper traces its development and vicissitudes, first as an independent Nature Conservancy, then as a part of the Natural Environment Research Council, and finally as the Nature Conservancy Council. Much has been achieved: ecology is now a household word; there is a strong voluntary tide for nature conservation in the country; and there have been notable achievements in practical conservation. But the dangers to nature in Britain have proved to be much greater than anticipated.  相似文献   

10.

Aim

Ecological refuges buffer organisms against stressors and mediate a range of species interactions. However, their role in the context of biological invasions has yet to be synthesized, despite the increasing prevalence and impact of non-native species. To address this, we conducted a systematic review aiming to determine the extent to which refuges are considered explicitly in the invasion literature and to synthesize their function.

Location

Global.

Time period

Present day.

Major taxa studied

All.

Methods

Our search of the literature was conducted using the SCOPUS and Web of Science databases and followed the preferred reporting items for systematic reviews and meta-analyses (PRISMA) protocol. We obtained 315 records of refuge use in biological invasions from 300 studies. From each record, we extracted information relating to the experimental design, species characteristics and refuge type, where available.

Results

Refuges and refuge-mediated processes are widely reported in the invasion literature. Native species commonly use refuges to avoid non-native predation and competition, with spatial complexity and habitat heterogeneity key factors in facilitating their coexistence. Records show that artificial structures safeguard non-natives in their introduced range. However, there were key differences in the use of such structures in marine and terrestrial environments. Moreover, the enhanced structural complexity created by non-native plants and bivalves is often reported to act as a predation refuge for other species.

Main conclusions

The ubiquity of refuge-based processes suggests that refuges can play an important role in affecting the persistence, spread and impacts of non-native species, either through previously described mechanisms (i.e. refuge-mediated apparent competition and the persistent pressure scenario) or through a mechanism we describe (i.e. when non-native species use existing refuges), or both.  相似文献   

11.
1. The Daphnia pulex‐pulicaria species complex has been proposed as an example of rapid ecological speciation, associated with divergence along the gradient of waterbody size from temporary ponds to deep, stratified lakes. However, this divergence is incomplete, and thus represents an opportunity to study ecological divergence as it is occurring. 2. Dynamics of twelve populations of Daphnia in the pulex‐pulicaria species complex were monitored over 1 year. Six temporary pond populations and six permanent lake populations were compared to evaluate demographic differences that may contribute to ecological divergence in this complex. 3. Pond populations experienced greater changes in density, which were reflected in more extreme growth rates, higher birth rates and higher mortality rates than those of lake populations. 4. Mitochondrial DNA was isolated from up to three clones from each population, the D‐loop of the control region was sequenced, and a phylogenetic tree was constructed. This tree revealed two strongly supported clades. The clades were not congruent with habitat type and nominal status, indicating that interhabitat gene flow occurs easily and that the nominal taxa are incompletely diverged. 5. Published reports of genetic life history differences in the D. pulex‐pulicaria complex are consistent with the demographic differences reported here. This suggests that ecological differences between the habitats are selectively maintaining trait differences despite the possibility for genetic exchange. Thus, these taxa may be at the inception of ecological speciation.  相似文献   

12.
13.
Summary A common approach to nature conservation is to identify and protect natural ‘assets’ such as ecosystems and threatened species. While such actions are essential, protection of assets will not be effective unless the ecological processes that sustain them are maintained. Here, we consider the role of ecological processes and the complementary perspective for conservation arising from an emphasis on process. Many kinds of ecological processes sustain biodiversity: including climatic processes, primary productivity, hydrological processes, formation of biophysical habitats, interactions between species, movements of organisms and natural disturbance regimes. Anthropogenic threats to conservation exert their influence by modifying or disrupting these processes. Such threats extend across tenures, they frequently occur offsite, they commonly induce non‐linear responses, changes may be irreversible and the full consequences may not be experienced for lengthy periods. While many managers acknowledge these considerations in principle, there is much scope for greater recognition of ecological processes in nature conservation and greater emphasis on long time‐frames and large spatial scales in conservation planning. Practical measures that promote ecological processes include: monitoring to determine the trajectory and rate of processes; incorporating surrogates for processes in conservation and restoration projects; specific interventions to manipulate and restore processes; and planning for the ecological future before options are foreclosed. The long‐term conservation of biodiversity and the well‐being of human society depend upon both the protection of natural assets and maintaining the integrity of the ecological processes that sustain them.  相似文献   

14.
The concept of ecosystem restoration is gaining momentum in western Europe. This is necessary because in most managed nature reserves one or more of the following processes, which are analogous to those that have led to the dramatic loss of biological diversity in Europe, are still operating: continuing nutrient output, continuing high level of disturbance and fixing the system in some successional stage. This is partly because most management activities have been derived from, or copy, former agricultural practices. The study of natural ecosystems has revealed the key role large herbivores have in maintaining structural diversity in the vegetation and so biological diversity. Because of this they have been used as tools in achieving a variety of conservation goals. Here, various effects large herbivores can have on plant species composition, structural diversity of the vegetation and fauna are briefly reviewed. Attention is given to pasture-woodlands in southern Europe, which often have a relatively high biological diversity and share some key features with natural ecosystems: very low nutrient input, extensive grazing with large herbivores and the presence of natural tree cover. In a number of European countries attempts are being made to restore normal functioning multi-(herbivore) species ecosystems.  相似文献   

15.
Conservation ecology is a new paradigm of ecology that aims at scientific contributions to maintaining earth's biodiversity and is committed to ecosystem management indispensable to intergenerational long-term sustainability. Population ecology plays a central role in conservation ecology. Persistence of the metapopulation rather than that of each local population should be pursued in species conservation management. Biological interactions essential to reproduction and soil seed bank components of the population should be investigated and applied to planning for the conservation of a plant population. Gravelly floodplains and moist tall grasslands are among typical riparian habitats containing many threatened plants in Japan. These riparian habitats are now subjected not only to heavy fragmentation but also to intensive invasion of highly competitive alien (nonnative) plants. Extreme habitat isolation may result in reproductive failure or fertility selection in a plant population without pollinators, as exemplified by a nature reserve population of Primula sieboldii. Biological invasions, which are facilitated by extensive changes in the river environment including decreased seasonal flooding, abandonment of traditional vegetation management, eutrophication, and extensive clearing of the land for recreational use, threaten endemic riparian species. To preserve safe sites and growing conditions for threatened plants such as Aster kantoensis, active management to suppress the dominance of alien invader plants is necessary. Population management and habitat restoration should be based on sound information on the population ecology of both threatened and alien invader plants, designed as an ecological experiment to clarify effective ways for management. Received: September 18, 1998 / Revised: October 22, 2001 / Accepted: October 23, 2001  相似文献   

16.
Steppe is among the most endangered biomes of the world, especially in Eastern Europe, where more than 90 % of original steppes have been destroyed due to conversion into croplands, afforestation and other human activities. Currently, steppe vegetation is often restricted to places unsuitable for ploughing, such as ancient burial mounds called kurgans. The aim of our study was to collect and synthesise existing knowledge on kurgans by a review of research papers and grey literature. The proportion of kurgans covered by steppe vegetation increases from west to east and from lowlands to uplands. Despite their small size, kurgans act as biodiversity hotspots and harbour many red-listed species. High overall species richness and a high proportion of grassland specialists are maintained by a pronounced fine-scale environmental heterogeneity. The main factors threatening the biodiversity of kurgans are intensified agriculture and construction works. We conclude that kurgans can play a crucial role in preserving steppe vegetation, especially in intensively used agricultural landscapes in the western part of the steppe zone. Despite the vital role of kurgans in sustaining steppe vegetation, we identified serious knowledge gaps on their distribution, vegetation, flora and fauna and their potential role in steppe restoration.  相似文献   

17.
The range and extent of nature conservation interests on land owned by the National Trust are reviewed and the high level of protection which can be afforded to such features is stressed. Some of the threats to such interests are examined and possible conflicts between management for nature conservation and for other Trust objectives are considered. The importance of survey and monitoring are emphasized. It is argued that nature conservationists need to adopt a view of plant communities which recognises their dynamic nature and which accepts the possibility of change. Evidence is reviewed which supports the non-equilibrium state of some communities, the impact of rare events and the importance of life history phenomena. Some possible future directions of nature conservation in the Trust are discussed.  相似文献   

18.
This essay explains the role of reproductive science, including what are termed reproductive technologies (i.e. artificial insemination, in vitro fertilization, embryo transfer, cloning), in conservation biology. Reproductive techniques (high- and low-tech) find their greatest application in understanding species uniqueness, adaptations and physiological mechanisms, not in the large-scale assisted breeding and the production of offspring. Models of how to use these tools to study reproductive fitness are emerging to help insure gene diversity and even propagate endangered species, but only after fundamental databases have been developed. Examples are provided of how non-invasive hormone metabolite monitoring, artificial insemination and genome resource banking are being used ex situ and in situ to understand wildlife biology. We predict that as the fundamental, multi-species database grows, so will the applied benefits for: (1) developing genome banks for insuring extant genetic diversity; (2) assessing the relationship of physiology, behaviour and environmental perturbations; (3) managing small populations; and (4) dealing with dilemmas ranging from contraception to skewed sex ratios to animal welfare. Most progress will be made in using these tools in systematic studies to solve the mystery of how thousands of unstudied species reproduce. Carried out appropriately, financial costs will be consistent with any approach for generating sound scientific knowledge.  相似文献   

19.
20.
Conservation policies and environmental impact assessments commonly target threatened species and habitats. Nevertheless, macroecological research provides reasons why also common species should be considered. We investigate the consequences of focussing solely on legally protected species and habitats in a spatial conservation planning context using a comprehensive, benthic marine data set from the northern Baltic Sea. Using spatial prioritization and surrogacy analysis, we show that the common approach in conservation planning, where legally listed threatened species and habitats are the focus of conservation efforts, could lead to poor outcomes for common species (and therefore biodiversity as a whole), allowing them to decline in the future. If conservation efforts were aimed solely at threatened species, common species would experience a loss of 62% coverage. In contrast, if conservation plans were based only on common species, threatened species would suffer a loss of 1%. Threatened species are rare and their ecological niches distinct, making them poor surrogates for biodiversity. The best results are achieved by unified planning for all species and habitats. The minimal step towards acknowledging common species in conservation planning would be the inclusion of the richness of common species, complemented by information on indicator species or species of high importance for ecosystem functioning. The trade-off between planning for rare and common species should be evaluated, to minimize losses to biodiversity.  相似文献   

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