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1.
高俊峰  张志明  蔡永久  黄佳聪 《生态学报》2022,42(14):5677-5691
我国目前处于生态环境管理的转型期,尚未形成统领水生生物、生物栖息地、水质与水量等要素的水生态保护体系。在总结相关水生态研究成果的基础上,梳理形成了基于水生态系统时空尺度和状态梯度效应理论的水生态保护目标制定构想与方法,分析了淡水生物完整性对自然地理要素、水环境压力、栖息地质量的响应机制,提出以水生态“功能分区-状态评价-问题诊断-目标预设-可达性评估-目标确定”为主线的水生态保护目标制定技术体系,研发了生物完整性评价、水生态保护目标预设和可达性分析等技术方法。以江苏省常州市为典型水生态功能区应用案例,验证了技术体系的适用性与可行性,取得良好的应用效果。水生态保护目标制定理论和方法方面的研究探索可为全国相关工作提供参考依据。  相似文献   

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Biodiversity targets, or estimates of the quantities of biodiversity features that should be conserved in a region, are fundamental to systematic conservation planning. We propose that targets for species should be based on the quantitative thresholds developed for the Vulnerable category of the IUCN Red List system, thereby avoiding future listings of species in an IUCN Red List threat category or an increase in the extinction risk, or ultimate extinction, of species already listed as threatened. Examples of this approach are presented for case studies from South Africa, including threatened taxa listed under the IUCN Red List criteria of A to D, a species listed as Near Threatened, a species of conservation concern due to its rarity, and one species in need of recovery. The method gives rise to multiple representation targets, an improvement on the often used single representation targets that are inadequate for long term maintenance of biodiversity or the arbitrary multiple representation and percentage targets that are sometimes adopted. Through the implementation of the resulting conservation plan, these targets will ensure that the conservation status of threatened species do not worsen over time by qualifying for higher categories of threat and may actually improve their conservation status by eliminating the threat of habitat loss and stabilizing population declines. The positive attributes ascribed to the IUCN Red List system, and therefore to the species targets arising from this approach, are important when justifying decisions that limit land uses known to be detrimental to biodiversity.  相似文献   

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Phylogenetic, genetic and demographic information are key issues for establishing priorities for conservation. In this study we explored the Vane-Wrigth measure of phylogenetic diversity for establishing criteria for conservation, when intra as well as interpopulation level demographic (population size) and genetic (heterozygosity, inbreeding and genetic distances among populations) parameters are taken into consideration. The data were standardized and analyzed independently and integratively enabling the calculation of indices or criteria for conservation priorities. We illustrate the application of this approach in populations of four Mexican pine species that have been considered rare and endangered, Pinus rzedowzkii, P. pinceana, P. lagunae and P. muricata. The application of several independent diversity indices did not allow us to resolve prioritization. However, the integration of all indices generated different values of importance to conservation, and suggested that the populations with the highest priorities for conservation are: two for Pinus rzedowskii, P. pinceana, and P. lagunae, and one for P. muricata. These populations have intermediate sizes, are the most divergent in the phylogeny and contain genetic variation that is representative of the gene pool of each species. Finally, we demonstrated the functionality of some genetic and demographic parameters; the genetic structure, recruitment rate, geographic distribution and demographic stochasticity, as complementary indicators for evaluating the conservation priority among populations and species.  相似文献   

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未来十年的生物多样性保护目标   总被引:4,自引:0,他引:4  
生物多样性作为人类生存与发展的基础,正以前所未有的速度丧失.据国际自然保护联盟(IUCN)报道,在他们评估的5.2万个物种中有36%受到严重威胁,全球六千多种两栖类中有30%受到严重威胁,自2000年以来每年有600万公顷原始森林丧失,在过去的20年中红树林丧失了35%,目前70%的珊瑚礁受到严重破坏(http://www.iucn.org/iyb/about/bio-diversity_crisis/).  相似文献   

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The statutory bodies in the United Kingdom advise Government on U.K. nature conservation and undertake site and species conservation. Active partnerships with other organizations and individuals are an important aspect of how this conservation work is undertaken. Current work on birds includes studies on introduced species, reintroduced species, marine species and agricultural issues. The concepts of sustainable use and the conservation of biodiversity figure highly in commitments for the future and will direct efforts on research and monitoring.  相似文献   

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Berg and colleagues, in this issue, describe a framework for assessing risks to biodiversity and setting conservation priorities in northeast Germany. Their method explicitly separates community endangerment from conservation value, and derives its plant communities from a sound regional classification. It could be improved by incorporating ecological processes into risk assessment, and socio‐political constraints, economic costs and the likelihood of success into priority setting.  相似文献   

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Background

A commonplace analysis in high-throughput DNA methylation studies is the comparison of methylation extent between different functional regions, computed by averaging methylation states within region types and then comparing averages between regions. For example, it has been reported that methylation is more prevalent in coding regions as compared to their neighboring introns or UTRs, leading to hypotheses about novel forms of epigenetic regulation.

Results

We have identified and characterized a bias present in these seemingly straightforward comparisons that results in the false detection of differences in methylation intensities across region types. This bias arises due to differences in conservation rates, rather than methylation rates, and is broadly present in the published literature. When controlling for conservation at coding start sites the differences in DNA methylation rates disappear. Moreover, a re-evaluation of methylation rates at intronexon junctions reveals that the magnitude of previously reported differences is greatly exaggerated. We introduce two correction methods to address this bias, an inferencebased matrix completion algorithm and an averaging approach, tailored to address different underlying biological questions. We evaluate how analysis using these corrections affects the detection of differences in DNA methylation across functional boundaries.

Conclusions

We report here on a bias in DNA methylation comparative studies that originates in conservation rate differences and manifests itself in the false discovery of differences in DNA methylation intensities and their extents. We have characterized this bias and its broad implications, and show how to control for it so as to enable the study of a variety of biological questions.

Electronic supplementary material

The online version of this article (doi:10.1186/s12864-015-1604-3) contains supplementary material, which is available to authorized users.  相似文献   

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Protected areas (PAs) are a cornerstone of conservation efforts and now cover nearly 13% of the world's land surface, with the world's governments committed to expand this to 17%. However, as biodiversity continues to decline, the effectiveness of PAs in reducing the extinction risk of species remains largely untested. We analyzed PA coverage and trends in species' extinction risk at globally significant sites for conserving birds (10,993 Important Bird Areas, IBAs) and highly threatened vertebrates and conifers (588 Alliance for Zero Extinction sites, AZEs) (referred to collectively hereafter as 'important sites'). Species occurring in important sites with greater PA coverage experienced smaller increases in extinction risk over recent decades: the increase was half as large for bird species with>50% of the IBAs at which they occur completely covered by PAs, and a third lower for birds, mammals and amphibians restricted to protected AZEs (compared with unprotected or partially protected sites). Globally, half of the important sites for biodiversity conservation remain unprotected (49% of IBAs, 51% of AZEs). While PA coverage of important sites has increased over time, the proportion of PA area covering important sites, as opposed to less important land, has declined (by 0.45-1.14% annually since 1950 for IBAs and 0.79-1.49% annually for AZEs). Thus, while appropriately located PAs may slow the rate at which species are driven towards extinction, recent PA network expansion has under-represented important sites. We conclude that better targeted expansion of PA networks would help to improve biodiversity trends.  相似文献   

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罗茂芳  杨明  马克平 《广西植物》2023,43(8):1350-1355
在中国作为主席国的引领下,联合国《生物多样性公约》(以下简称《公约》)第十五次缔约方大会(以下简称COP15)第二阶段会议通过了62项决定,特别是达成了以变革理论为基础的《昆明-蒙特利尔全球生物多样性框架》(以下简称《昆蒙框架》),为全球生物多样性治理擘画了新的蓝图。该文就《昆蒙框架》的三个核心目标——保护地“3030目标”、资源调动、遗传资源数字序列信息进行解读,对保障《昆蒙框架》落地的相关决议进行简要介绍,并就我国未来的保护行动提出了相关建议:(1)加强生物多样性保护的主流化;(2)进一步制定详细的保护计划,明确保护区域的范围、目的和管理措施,并落实实施计划的责任部门和具体措施;(3)根据框架目标的监测要求,制定可操作的指标体系和监测计划;(4)继续加强生物多样性保护的意识和教育,提高公众对生物多样性保护的认识和重视程度,促进全社会的可持续生产和可持续消费;(5)大力推进国际合作,在更大尺度上探索和促进基于自然的解决方案,寻找对自然产生正面、积极效果的经济和社会发展路径。  相似文献   

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Wild rhododendron (Rhododendron ponticum) is widely regarded by conservationists as a scourge of the British countryside. However, in its native haunts such as Turkey, it is also one of Europe's most threatened species, with ancient rhododendron forests now reduced to only a few hectares.  相似文献   

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The United Kingdom Biodiversity Action Plans includes protection plans for 27 liverworts and 76 mosses. One of the most complicated examples of British plant rarity concerns the leafy liverwort Telaranea. Of the three species recognized in the literature for the British Isles, two (T. tetradactyla and T. murphyae) have been considered recent introductions to the British flora, because their occurrence is restricted to in or near botanic gardens. Both species have recently been transferred to the genus Tricholepidozia. Tricholepidozia murphyae, unlike any other bryophyte on the British Red List, is regarded as non-native, of unknown origin. We selected two molecular markers from different genomic compartments to fit in with existing datasets for Lepidoziaceae, in order to elucidate the origin and affinities of this enigmatic, non-native British endemic, and thus assist prioritization of conservation efforts. We sequenced multiple accessions of all three currently recognized British Telaranea and Tricholepidozia. Based on sequence data, while Telaranea europea is genetically isolated from all other sequenced Lepidoziaceae, it seems that Tricholepidozia murphyae merely represents a separate genetic introduction from the Austral T. tetradactlya/T. lindenbergii species group into the British Isles, and as such, in the UK it should be considered of low conservation priority. We thus synonymize T. murphyae under T. tetradactyla, while acknowledging that taxonomy within the T. tetradactlya/T. lindenbergii species complex still requires revision.  相似文献   

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It has been possible to regenerate a few cycad species in vitro by somatic embryogenesis, either from zygotic embryos (Ceratozamia hildae, C. mexicana, Encephalartos cycadifolius,E. dyerianus, E. natalensis, Zamia fischeri, Z. furfuracea, andZ. pumila) or from leaves of mature phase trees (C. euryphyllidia, Ceratozamia hildae, andC. mexicana). This strategy has great potential for the commercial vegetative propagation of certain highly endangered species (e.g.,C. euryphyllidia) and should indirectly protect wild populations of these species by discouraging collection in situ. Embryogenic cultures of several cycad species have grown vigorously and are highly morphogenic more than 11 years after induction. The long-term conservation of cycad genetic resources can also be addressed for species that can be regenerated by somatic embryogenesis. Preliminary studies indicate that embryogenic cultures that have been pretreated on plant growth medium containing 0.75 M sucrose for two days, encapsulated in sodium alginate, and desiccated for six hours can survive immersion in liquid nitrogen (−196°C).  相似文献   

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