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351.
The Global Strategy for Plant Conservation (GSPC) set an ambitious target to achieve a conservation assessment for all known plant species by 2020. We consolidated digitally available plant conservation assessments and reconciled their scientific names and assessment status to predefined standards to provide a quantitative measure of progress toward this target. The 241,919 plant conservation assessments generated represent 111,824 accepted land plant species (vascular plants and bryophytes, not algae). At least 73,081 and up to 90,321 species have been assessed at the global scale, representing 21–26% of known plant species. Of these plant species, at least 27,148 and up to 32,542 are threatened. Eighty plant families, including some of the largest, such as Asteraceae, Orchidaceae, and Rubiaceae, are underassessed and should be the focus of assessment effort if the GSPC target is to be met by 2020. Our data set is accessible online (ThreatSearch) and is a baseline that can be used to directly support other GSPC targets and plant conservation action. Although around one‐quarter of a million plant assessments have been compiled, the majority of plants are still unassessed. The challenge now is to build on this progress and redouble efforts to document conservation status of unassessed plants to better inform conservation decisions and conserve the most threatened species. 相似文献
352.
阐明了能使防护林体系水土保持功能达到持续和稳定提高的造林和经营配套技术 相似文献
353.
丛枝菌根对盐胁迫的响应及其与宿主植物的互作 总被引:1,自引:0,他引:1
丛枝菌根真菌(Arbuscular Mycorrhizae Fungi,AMF)作为陆地生态系统的组成部分之一,在促进宿主植物对土壤养分和水分的吸收、提高植物生物量生产、调节种群和群落的结构、维持生态系统的稳定性等方面发挥了重要作用。其中,盐渍化是自然生态系统中广泛存在的一种胁迫生境条件,全球盐渍化土地约占耕地总面积的10%,因而探讨AM菌根在此胁迫生境下对宿主植物生长的影响具有重要意义。从以下几个方面,围绕盐胁迫条件、AM菌根和宿主植物三者之间的关系对当前国际上相关领域的研究进展进行了综述:1)AM真菌对盐胁迫的响应,包括菌根共生体形成、菌根侵染率、AM真菌的分布、菌丝体生长发育、孢子的形成和分布等;2)盐胁迫条件下AM菌根对宿主植物的效应,包括AM菌根促进宿主植物对P、N等元素的吸收、降低植物体内Na 的含量、提高光合作用能力,进而提高植物的生物量和对植物的群落结构产生影响等;3)AM菌根提高宿主植物耐盐性的机理,分别从植物根系形态的改变、水分吸收能力的加强、细胞内营养物质的平衡,以及细胞生理代谢的调节等方面对AM菌根促进植物抗盐性的机理进行了剖析。 相似文献
354.
生物多样性保护依赖于健全的国际立法和国家立法。中国已颁布一系列有关生物多样性保护的法律和条例。这些法规的实施,使生物多样性保护工作取得重大进展,但还存在许多不足和空白。本文概述了中国在生物多样性保护方面的立法现状,在此基础上,针对存在问题,并根据《生物多样性公约》要求,从生态系统、物种和遗传多样性保护3个层次上阐明需要完善和加强法规建设的若干方面和需求。 相似文献
355.
王献溥 《生态与农村环境学报》1995,(4)
当前,任何地区的生物多样性都是自然和社会因素长期综合作用所造成。生物多样性最丰富的地区不一定全部由顶极植被所覆盖,而常常是一些包括所有演替类型的地方。本文通过讨论自然环境的变化和人类生产活动对不同区域景观的影响,探讨有关生物多样性的保护问题。 相似文献
356.
白效明 《生态与农村环境学报》1993,(4)
本文针对目前环境保护的热点之一——全球和地区性生物多样性保护,对其中的一个基础理论问题,即区域生物多样性评价标准进行了探索;从理论上对制定这一标准的必要性、可行性、生物多样性的基本内涵、区域生物多样性中心标准的意义及标准制定的原则和依据进行了阐述,并在此基础上提出了我国区域生物多样性中心标准的基本框架。 相似文献
357.
KAZUE ASOH§ TOMOKO YOSHIKAWA† RANDALL KOSAKI‡ ELIZABETH A. MARSCHALL 《Conservation biology》2004,18(6):1645-1650
Abstract: Many fishing methods and gear types used in coral reefs cause physical damage to the reef substratum. Only recently have monofilament fishing lines been recognized as a cause of coral damage and death. We assessed the extent of damage caused by monofilament fishing lines to the cauliflower coral ( Pocillopora meandrina ) colonies in fished and adjacent unfished zones at seven sites in the main Hawaiian islands. We examined coral colonies for the presence or absence of fishing line and for the degree of damage (dead, no live coral surface; damaged, some dead coral surface; or intact, no dead coral surface) in nine 25-m2 grids. The mean proportion of colonies entangled with fishing lines in fished zones ranged from 0.18 to 0.44. The mean proportion of dead or damaged colonies was higher in fished than adjacent unfished zones, and there was a positive linear relationship between the proportion of colonies entangled with fishing lines and the proportion of dead or damaged colonies. These results indicate that monofilament fishing lines have a negative impact on the health and survival of P. meandrina colonies. Because tourism and related recreational fishing activities are expanding rapidly in many tropical states and nations, we recommend that the degrading effects of fishing lines on corals be considered in the design and management of tourism development. 相似文献
358.
超高浓度萘系磺酸染料中间体废液资源化 总被引:1,自引:0,他引:1
王连生 《城市环境与城市生态》1995,8(3):11-14
本文介绍了胺盐萃取回收率液中萘磺酸染料中间体的方法,回收率达95%以上,回收浓缩液工艺套用,10t/d废液量的资源化年净效益达580万元,投资费用两个月即可全部收回,采用Langmuir等温方程描述体系中萃取剂用量,待萃物含量和萃取率的关系,使工艺参数的确立和工程设计完全处理指导之下。 相似文献
359.
SVEN WUNDER 《Conservation biology》2007,21(1):48-58
360.
Is Current Consumption Excessive? A General Framework and Some Indications for the United States 总被引:3,自引:0,他引:3
Abstract: Many prior studies have explored the implications of human population growth and environmentally problematic technologies for biodiversity loss and other forms of environmental degradation. Relatively few, however, have examined the impacts of the level and composition of consumption. We offer a framework that shows how the level and composition of a society's total consumption relate to the uses of various forms of capital and to the sustainability of natural resources and human well-being. We relate the framework to two main approaches—top–down macro studies and bottom–up computer models—for measuring whether overall consumption in the United States satisfies a sustainability requirement. Existing top–down studies have shortcomings that bias their results toward optimism, and current computer simulation models, although strong on revealing biophysical outcomes, are limited in their ability to evaluate impacts on human well-being. Although some ambiguities arise in determining whether overall consumption in the United States is excessive, our conclusions regarding the composition of U.S. consumption are unambiguous. Distorted consumption patterns and associated production methods lead to excessively rapid natural resource depletion; greater conservation would yield gains to current and future generations that more than compensate for the sacrifices involved. Public policies that deal with the composition problem not only would help conserve natural resources and improve current welfare but also would reduce the costs of meeting the goal of sustainability. 相似文献