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991.
As conservation reserves expand, the likelihood that they will capture areas degraded by previous land use increases. Ecological restoration of such areas will therefore play an increasing role in biodiversity conservation. On the New South Wales North Coast, recent expansion in the conservation estate has captured over 300 softwood and hardwood plantations, many with understoreys dominated by exotic weeds. Here we present an overview of the practices we have adopted in managing flooded gum (Eucalyptus grandis) plantations infested with lantana (Lantana camara) to enhance their biodiversity value. Experiments designed to overcome barriers limiting regeneration of native forest in conjunction with measurement of soil and plant responses yielded insights into the management of former timber plantations for biodiversity. Canonical Correspondence Analysis indicated that the level of canopy retention (or logging intensity) within sites consistently explained the greatest amount of variation in plant community composition (32–38% post-treatment). Thinning and burning stimulated regeneration of native species. Retained canopy cover was proportional to the richness or abundance of native woody shrubs, understorey trees and native perennial herbs, indicating that management intensity can be varied to promote a range of conservation values. A state-and-transition model summarising purported management actions and likely outcomes for these plantations is presented. This is the first time plantations have been managed solely for biodiversity. Logging income means that plantation restoration can be cost-neutral, and the positive influence of a cover crop of trees means that plantation management may generally be manipulated to promote biodiversity conservation.  相似文献   
992.
The present work provides an overview of the global use of reptiles in traditional folk medicine and the implications for conservation. The results demonstrate that at least 165 reptile species belonging to 104 genera and 30 families are used in traditional folk medicine around the world. Some species are used as sources of drugs for modern medical science. Of the reptiles recorded, 53% are included on lists of endangered species, demonstrating the importance of understanding such medicinal uses in the context of reptile conservation as well as the need for considering socio-cultural factors when establishing management plans directed towards the sustainable use of these reptiles.  相似文献   
993.
Butterfly monitoring in Europe: methods,applications and perspectives   总被引:1,自引:0,他引:1  
Since the first Butterfly Monitoring Scheme in the UK started in the mid-1970s, butterfly monitoring in Europe has developed in more than ten European countries. These schemes are aimed to assess regional and national trends in butterfly abundance per species. We discuss strengths and weaknesses of methods used in these schemes and give examples of applications of the data. A new development is to establish supra-national trends per species and multispecies indicators. Such indicators enable to report against the target to halt biodiversity loss by 2010. Our preliminary European Grassland Butterfly Indicator shows a decline of 50% between 1990 and 2005. We expect to develop a Grassland Butterfly Indicator with an improved coverage across European countries. We see also good perspectives to develop a supra-national indicator for climate change as well as an indicator for woodland butterflies.  相似文献   
994.
Secondary forests constitute a growing portion of forested areas worldwide. They might have a substantial role for the conservation of biodiversity in tropical areas, but there is little information on their potential to support forest species and the recovery of faunal communities. We studied two forest frogs (Eleutherodactylus diastema and E. fitzingeri) in an area of Costa Rica composed of a mosaic of primary forest, young secondary forest and pasture, and we compared the density of calling males in areas with different forest alteration. Autoregressive models were used to compensate for potentially undesired effects of spatial autocorrelation and pseudoreplication. Both species were most abundant in riparian, primary forest. However, E. fitzingeri was also abundant in riparian secondary forests, and its density far from the river was similar in primary and secondary forest, suggesting that river proximity can influence the recovery of secondary forest for amphibians. Conversely, the density of E. diastema was similar in secondary forest and pasture, stressing interspecific differences for recovery rate. These frogs have a keystone role in nutrient cycling and food webs, and their prompt recovery might represent an important step for the functional recovery of forests. Nevertheless, the strong interspecific differences stress the complexity of these processes.  相似文献   
995.
秤锤树属与长果安息香属植物的地理分布及其濒危现状   总被引:10,自引:0,他引:10  
秤锤树属(SinojackiaHu)和长果安息香属(ChangiostyraxC.T.Chen)是安息香科的少种属,这两属在我国共记录有7个种。本文通过野外调查,分析了中国这两属植物的地理分布、濒危现状及其迁地保护状况。结果表明:秤锤树属植物地理分布较广,但是每个物种的居群数量和居群大小均很小。其中秤锤树(Sinojackiaxylocarpa)和狭果秤锤树(S.rehderiana)已经在其模式标本产地灭绝;棱果秤锤树(S.henryi)在过去的近70年内没有采到过标本,该物种可能存在同物异名现象或已经灭绝;细果秤锤树(S.microcarpa)由于人为破坏严重,居群大小急剧下降;肉果秤锤树(S.sarcocarpa)和怀化秤锤树(S.oblongicarpa)呈零星分布且个体数量很少,处于极濒危状态。另外本次调查发现秤锤树属的一个新的分类群(待鉴定种)。秤锤树属的大多数种和长果安息香属植物的居群更新能力差:虽然结果率较高,但是结籽率较低;坚硬的内果皮阻碍了种子的萌发,这是其居群更新的最大障碍;另外人为破坏对其居群更新的影响也较大。作者建议应该把秤锤树属的所有物种和长果安息香属植物都纳入保护的范围并讨论了这两属植物的保护策略。  相似文献   
996.
云南省香格里拉大峡谷藏族神山在自然保护中的意义   总被引:12,自引:1,他引:11  
位于云南省西北部迪庆藏族自治州境内的香格里拉大峡谷拥有独特的自然人文景观和丰富的生物多样性。藏族作为当地最重要的原住民族,他们的文化对当地的自然环境具有重要的影响。为了解藏族传统文化中的神山崇拜对香格里拉大峡谷地区自然环境的影响,本文应用民族生态学、植物生态学和文化人类学的研究方法,结合文献资料的分析,对香格里拉大峡谷的藏族神山进行了调查和研究,并对处于不同保护状态下(神山与非神山)的两个典型植物群落即高山松(Pinus densata)群落和云南黄果冷杉(Abies ernestii var. salouenensis)群落进行了比较。结果显示,在相同的样地面积内(20 m×20 m),神山植物群落在物种数量(20,14)和群落盖度(100%,85%)方面都明显高于非神山植物群落(11,2;70%,60%)。结合入户调查资料,发现广泛分布于香格里拉大峡谷的藏族神山构成了一个“自下而上”的乡土保护体系,它不仅在保护生物多样性、维护当地脆弱的生态环境等方面发挥着重要的作用,而且还可以提供多种非林产品,实现多种生态功能。文章探讨了发挥乡土保护体系的保护功效及应用传统文化知识以促进自然保护的重要性,建议应当尊重和保护原住民的传统文化,发掘其中优秀的自然保护知识和经验,引导其发挥更加有效的自然保护功能,使民族传统保护体系成为现代自然保护体系的有力补充。  相似文献   
997.
重寄生属(Phacellaria)植物共有8个种,其地理分布主要局限于东南亚和我国华南和西南地区的亚热带和热带山地森林中,其中我国分布有6个种。重寄生属植物的寄主仅局限于桑寄生科(Loranthaceae)和檀香科(Santalaceae)寄生藤属(Dendrotrophe)的植物。作者在查阅国内主要标本馆的馆藏标本、野外调查并结合已有研究报道的基础上,详细分析了我国重寄生属植物目前的生存现状,认为它们已经处于渐危或濒危的境地。造成重寄生属植物渐危或濒危的主要因素是森林过度砍伐导致的重寄生植物寄主种群密度的降低;与重寄生植物种子传播者啄花鸟类的生境片断化和数量的减少等也有密切的关系。重寄生属植物与其寄主、种子传播者啄花鸟类和生境中的其他生物形成了复杂的关系,是生物多样性的重要组成部分。因此,有必要对重寄生属植物进行保护。提出了保护重寄生属植物的生境、保护啄花鸟类和加强其生物学特性研究等保护对策。  相似文献   
998.
洞庭湖流域曾有亚洲象(Elephasmaximus)、犀(Rhinocerossp.)、麋鹿(Elaphurusdavidianus)、川金丝猴(Rhinopithecusroxellana)、长臂猿(Hylobatessp.)、大熊猫(Ailuropodamelanoleuca)、梅花鹿(Cervusnippon)、棕熊(Ursusarctos)等哺乳动物分布,但受古气候、古地理以及人类活动的影响,这些哺乳动物已在洞庭湖流域灭绝。这些哺乳动物的濒危和灭绝既受自然环境变化和灾变的影响,也与物种本身生物学特性和人类活动有关,尤其与人类捕杀和生境丧失有关。据古籍记载分析:在洞庭湖流域,亚洲象和犀于北宋末期灭绝或已南迁,而野生麋鹿、大熊猫、川金丝猴、长臂猿、梅花鹿和棕熊等于19世纪末灭绝。根据我们对30个自然保护区或森林公园野生动物资源实地调查的结果,在洞庭湖流域已记录到21种国家重点保护哺乳动物,其中有5、6、10种哺乳动物分别处于“极危”、“濒危”、“易危”等级,这表明物种濒危的过程仍在继续。导致这些现生哺乳动物濒危的主要原因是生境丧失、人类猎捕、环境污染等,而人类活动干扰对现生濒危物种存活的影响越来越大。洞庭湖流域重引入麋鹿需采取人类协助生存策略:提供足够的且受洪水影响小的适宜生境、保证稳定的奠基者种群数量、减少人为干扰、调控种群密度、实施社区共管和生计替代项目、加强疾病防治、完善保护措施、加大保护基金投入、加强生境监测和湿地恢复等。  相似文献   
999.
The distributions of eight out of nine common species of waders (Charadrii) overwintering on UK estuaries have changed in association with recent climate change. These birds represent a high proportion of various populations from breeding grounds as far apart as Greenland to the west to high‐arctic Russia to the east. During warmer winters, smaller proportions of seven species wintered in south‐west Britain. The distributions of the smaller species show the greatest temperature dependence. The opposite was found for the largest species and no relationship was found for a particularly site‐faithful species. In north‐west Europe, the winter isotherms have a broadly north to south alignment, with the east being colder than the west. The average minimum winter temperatures across the UK having increased by about 1.5°C since the mid‐1980s, the temperatures on the east coast during recent winters have been similar to those of the west coast during the mid‐1980s. On average, estuaries on the east and south coasts of Britain have muddier sediments than those on the west coast and thus support a higher biomass of the invertebrate prey of waders. We suggest that, with global climatic change, the advantage gained by waders wintering in the milder west to avoid cold weather‐induced mortality is diminished. Consequently, more choose to winter in the east and thus benefit from better foraging opportunities. The implications of these results are considered in terms of a site‐based approach to wildlife protection used in Europe and elsewhere.  相似文献   
1000.
Abstract Habitat models are now broadly used in conservation planning on public lands. If implemented correctly, habitat modelling is a transparent and repeatable technique for describing and mapping biodiversity values, and its application in peri‐urban and agricultural landscape planning is likely to expand rapidly. Conservation planning in such landscapes must be robust to the scrutiny that arises when biodiversity constraints are placed on developers and private landholders. A standardized modelling and model evaluation method based on widely accepted techniques will improve the robustness of conservation plans. We review current habitat modelling and model evaluation methods and provide a habitat modelling case study in the New South Wales central coast region that we hope will serve as a methodological template for conservation planners. We make recommendations on modelling methods that are appropriate when presence‐absence and presence‐only survey data are available and provide methodological details and a website with data and training material for modellers. Our aim is to provide practical guidelines that preserve methodological rigour and result in defendable habitat models and maps. The case study was undertaken in a rapidly developing area with substantial biodiversity values under urbanization pressure. Habitat maps for seven priority fauna species were developed using logistic regression models of species‐habitat relationships and a bootstrapping methodology was used to evaluate model predictions. The modelled species were the koala, tiger quoll, squirrel glider, yellow‐bellied glider, masked owl, powerful owl and sooty owl. Models ranked sites adequately in terms of habitat suitability and provided predictions of sufficient reliability for the purpose of identifying preliminary conservation priority areas. However, they are subject to multiple uncertainties and should not be viewed as a completely accurate representation of the distribution of species habitat. We recommend the use of model prediction in an adaptive framework whereby models are iteratively updated and refined as new data become available.  相似文献   
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