三横山人工鱼礁区鱼类和大型无脊椎动物诱集效果初探

为了解人工鱼礁投放对鱼类和大型无脊椎动物(简称FM,以下同)的诱集效果,分别于2007年5、9月和2009年3、5、7月对上三横山人工鱼礁B区与泥底区进行了拖网本底和跟踪调查,并于2009年1-8月对下三横山人工鱼礁A区与鳗头山岩礁和泥底区进行了刺网调查。采用CPUE、Margalef种类丰富度d、经济种类数变化、Whilm多样性指数H′′等反映FM的资源状况。结果显示,(1)鱼礁A区和岩礁区在CPUE、种类丰富度、经济种和多样性上均无明显差异(P>0.05),而两者各指标与泥底区皆存在显著差异(P<0.05);(2)鱼礁B区,投礁后CPUE和经济种类数都明显高于投礁前也大于同期对照区,差异显著(P<0.05);礁区平均丰富度水平高出同期对照区31.1%(P<0.05);多样性水平相对投礁前和对照区都有一定提高,但尚无显著差异(0.05相似文献   

浙江舟山桃花岛的天然植被类型

以点-线结合法等对桃花岛天然植被进行了调查,根据群落外貌特征,建群层片中相同生活型植物重要值大小及建群种的异同将该岛的天然植被划分为8个植被型,即:Ⅰ、常绿阔叶林;Ⅱ、落叶阔叶林;Ⅲ、常绿、落叶阔叶混交林;Ⅳ、暖性针叶、阔叶混交林;Ⅴ、暖性针叶林;Ⅵ、常绿阔叶灌丛;Ⅶ、灌草丛;Ⅷ、草甸。以此该岛植被可进一步划分为12个群系,即:1.青冈、石楠、刺叶桂樱林;2.南京椴、枫香林;3.枫香林;4.红楠、日本珊瑚树、落叶树林;5.青冈、红楠、枫香林;6.马尾松、青冈、枫香林;7.马尾松林;8.柃木灌丛;9.滨柃、赤楠灌丛;10.禾草灌丛;11.沙钻苔草、绢毛飘拂草、肾叶打碗花草甸;12.碱蓬、钻形紫菀群落。本文对各群系的组成及结构特征进行了描述。根据目前更新层树种的重要值分析后,笔者认为现有的主要森林群落若加以保护,将较快地演替为常绿阔叶林。鉴于岛屿植被的特殊性,在植被片下划分植被小区时,舟山群岛可单独划为岛屿植被小区。     

The influence of habitat availability and landscape structure on the distribution of wood cricket (Nemobius sylvestris) on the Isle of Wight, UK

Little information is available regarding the landscape ecology of woodland invertebrate species with limited dispersal ability. An investigation was therefore conducted within woodland fragments in an agricultural landscape for the flightless wood cricket (Nemobius sylvestris) on the Isle of Wight, UK. The current pattern of distribution of the species, established during a field survey, was related to measures of habitat availability and habitat isolation/fragmentation. Results revealed that wood cricket populations were patchily distributed and mainly found in relatively large mature woodland fragments situated closely (<50 m) to another occupied site. Although the occurrence of wood cricket was related to fragment area, isolation, habitat availability and woodland age, a logistic regression model revealed that presence of the species was most accurately predicted by fragment isolation and area alone. These results highlight the vulnerability of relatively immobile woodland invertebrate species, such as wood cricket, to the impacts of habitat loss and fragmentation.     

特呈岛种子植物区系研究

据野外植物调查与室内鉴定,特呈岛种子植物区系合计有种子植物112科393属556种,其中,木本植物有290种,草本有207种,藤本植物59种;本地野生种有343种,外来种213种。以热带性区系成分为主,温带成分主要为外来种类,区系具明显热带性质。优势建群植物种类组成的主要植被类型有潮间带红树林、沿岸木麻黄林、村落风水林、农田人工作物植被与草地。     

特呈岛白骨壤古树群的调查分析

特呈岛白骨壤古树群是我国极其珍贵的红树林资源,该古树群有510株古树,依据古树植株生长势可分为4级：Ⅰ级树势良好株46．47％、Ⅱ级树势正常株37．45％、Ⅲ级树势衰弱株13．92％、Ⅳ级垂死株2．16％。建议加强该古树群的保护复壮管理。     

特呈岛红树林资源保护与利用研究

特呈岛的红树林资源,尤其是其中的白骨壤古树群,是我国珍稀的海岸自然资源,有重要的自然资源保护与利用价值。通过古树复壮、生长环境优化、园林规划与生态旅游等措施的实施,该红树林资源得到了有效保护,并已成为湛江生态旅游的新亮点;通过研究获得了白骨壤果实的初试产品“榄钱果”、“榄钱豆”,表明进行资源有效开发利用能取得资源保护与资源利用双赢的效果。     

Public green space and disabled users

Social statistics indicate that the proportion of disabled people in the economically developed societies of the Western world is increasing. Thus more and more people are relying on special assistance and services. Environmental pollution and individual stress pose significant burdens to the majority of the constantly increasing urban population, especially the disabled, because they are dependent on suitable environments to serve their needs. These problems need to be remedied through planning and management. An empirical survey of the Isle of Mainau, located on Lake Constance in Southern Germany, shows that people with officially recognised disabilities feel stigmatised by green space that is specially designed for visitors with handicaps. People with lighter handicaps would like to have more attention and services rendered to them. ‘Standard users’, particularly those of higher income with better education, are reluctant to concede the entire island park's design and infrastructure to accommodate the needs of disabled visitors.     

Congenital bone deformities and the inbred wolves (Canis lupus) of Isle Royale

The wolf (Canis lupus) population on Isle Royale, a remote island in Lake Superior, North America, is extremely inbred. Nevertheless, the consequences of genetic deterioration have not been detected for this intensively studied population, until now. We found that 58% (n = 36) of Isle Royale wolves exhibited some kind of congenital malformation in the lumbosacral region of the vertebral column and 33% exhibited a specific malformity, lumbosacral transitional vertebrae. By contrast, only 1% (1 of 99) of wolves sampled from two outbred, wolf populations exhibited this malformity. Moreover, in domestic dogs (Canis lupus familiaris) lumbosacral transitional vertebrae are associated with cauda equina syndrome, which can cause paresis, paralysis, locomotor difficulties in the rear legs and tail, and back pain. Whereas many studies illustrate how genetic deterioration affects population-level phenomena, such as survival and reproduction, these results are distinctive for demonstrating how genetic deterioration has compromised the morphology of individuals in a free-ranging population. The results are also significant because many policy makers and stakeholders and some conservation professionals use examples like Isle Royale wolves to downplay the consequences of genetic deterioration.     

特呈岛红树林土壤总砷及多态砷含量测定

采用氢化物一原予荧光光谱法分析表明：特呈岛红树林中白骨壤古树群落和红海揽群落土壤无砷污染,总砷含量及五态砷合计含量均小于10mg／kg,其中以残渣态砷和Fe-结合态砷为主,后者占五种形态砷合计的25．6％-72．2％,土壤Fe-结合态砷〉交挟态砷〉AI-结合态砷〉Ca-结合态砷。