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981.
Survey‐gap analysis in expeditionary research: where do we go from here?   总被引:2,自引:0,他引:2  
Research expeditions into remote areas to collect biological specimens provide vital information for understanding biodiversity. However, major expeditions to little‐known areas are expensive and time consuming, time is short, and well‐trained people are difficult to find. In addition, processing the collections and obtaining accurate identifications takes time and money. In order to get the maximum return for the investment, we need to determine the location of the collecting expeditions carefully. In this study we used environmental variables and information on existing collecting localities to help determine the sites of future expeditions. Results from other studies were used to aid in the selection of the environmental variables, including variables relating to temperature, rainfall, lithology and distance between sites. A survey gap analysis tool based on ‘ED complementarity’ was employed to select the sites that would most likely contribute the most new taxa. The tool does not evaluate how well collected a previously visited site survey site might be; however, collecting effort was estimated based on species accumulation curves. We used the number of collections and/or number of species at each collecting site to eliminate those we deemed poorly collected. Plants, birds, and insects from Guyana were examined using the survey gap analysis tool, and sites for future collecting expeditions were determined. The south‐east section of Guyana had virtually no collecting information available. It has been inaccessible for many years for political reasons and as a result, eight of the first ten sites selected were in that area. In order to evaluate the remainder of the country, and because there are no immediate plans by the Government of Guyana to open that area to exploration, that section of the country was not included in the remainder of the study. The range of the ED complementarity values dropped sharply after the first ten sites were selected. For plants, the group for which we had the most records, areas selected included several localities in the Pakaraima Mountains, the border with the south‐east, and one site in the north‐west. For birds, a moderately collected group, the strongest need was in the north‐west followed by the east. Insects had the smallest data set and the largest range of ED complementarity values; the results gave strong emphasis to the southern parts of the country, but most of the locations appeared to be equidistant from one another, most likely because of insufficient data. Results demonstrate that the use of a survey gap analysis tool designed to solve a locational problem using continuous environmental data can help maximize our resources for gathering new information on biodiversity. © 2005 The Linnean Society of London, Biological Journal of the Linnean Society, 2005, 85 , 549–567.  相似文献   
982.
Modeling Historical Ecology, Thinking about Contemporary Systems   总被引:1,自引:1,他引:0  
One way to make archaeological trajectories compelling to contemporary audiences is through detailed computer simulation with graphical interfaces that allow students or researchers to explore historical sequences and ask "what if" questions of them. We discuss progress on modeling coupled human systems and ecosystems over long periods in the Mesa Verde region of the U.S. Southwest, a project developed with both research and educational products in mind. The project has many foci, but here we concentrate on fuel-wood availability and its pre-Hispanic use in the pygmy forests of this region. Our preliminary results tend to indicate that wood for fuels became sufficiently limited in this sequence to become a factor of considerable importance in decisions about where to live, how to build, and even whether to remain in the region. The same logic of modeling can be used to study problems of contemporary forest use in other parts of the world.  相似文献   
983.
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985.
曲卉  柳毅  陈雅文  汪晖 《遗传》2022,(2):107-116
印迹基因是由大约100个基因组成的一类特殊子集,主要以亲本单等位基因的方式表达,对胚胎的生长发育具有重要作用.近年来发现,环境因素所引起的印迹基因表观遗传修饰改变可造成胎儿多脏器发育不良甚至成年后多疾病易感,且存在多代遗传效应.本文基于国内外最新研究进展,总结了印迹基因表达改变对个体发育阶段以及生命后期器官功能的影响,...  相似文献   
986.
Although it was claimed that the Kuwait Master Plans have helped guide the development in Kuwait from a small mud brick town of 150,000 inhabitants to today's modern metropolis of about 3 million inhabitants, this article argues that the implementation of the first plan in 1952 planted the seeds of human and ecological risk problems in Kuwait, which were intensified later in the 1960s and 1970s. As the latest 2007 Master Plan comprises major development projects, which could certainly have adverse ecological impacts on the environment and human well-being, this article highlights the importance of integrating environmental impact assessment (EIA) and the development projects within the Master Plan as a tool for sustainable development and as an assessment of human and ecological risks before the implementation of such projects. According to the current status, the level of collaboration among the concerned organizations responsible for preparing the Master Plans and conducting the EIA is behind the ambition. This article recommends setting out documented environmental criteria for land use planning and major development projects implementation, so as to control pollution and prevent any environmental change that might impair the public's health or influence future ecological stability.  相似文献   
987.
988.
Summary   All forests, including commercial plantations, provide a range of habitats for conserving and enhancing elements of native biodiversity. However, the biodiversity values of commercial plantations will depend on the management practices adopted on site, as well as the landscape context of the plantation. The present study describes a generic, quantitative method for assessing the potential biodiversity benefits that might be derived from a plantation, depending on the management practices adopted. This method is based on existing ecological design and management principles. The Plantation Biodiversity Benefits Score (PBBS) was designed to be repeatable and practical to apply. The method can be used either as a stand-alone tool or as part of an integrated framework to assess and compare the commercial and environmental benefits that can be derived from different layouts, management practices and locations of plantations anywhere in Australia.  相似文献   
989.
990.
三种绢蝶翅脉数字化特征的提取及初步分析   总被引:5,自引:1,他引:4  
利用化学方法去除3种绢蝶翅面的鳞片和斑纹,通过扫描获取翅脉标本图片,并利用DrawWing、TPSDig和BugShape3种软件对其前翅左侧翅脉的数字特征进行了提取,并包括DrawWing提取的小红珠绢蝶右翅翅脉特征值。分析了小红珠绢蝶左右翅脉的对称性以及个体间的差异,对比了3种软件在3种绢蝶分类判别中的优劣。不仅对改进这些工具提出了建议,而且讨论了昆虫鉴定领域中数字化技术和形态测量学的应用前景。  相似文献   
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