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1.
The ability of landscape architectural projects to mitigate the worst effects of climate change will depend upon designed ecological systems. These systems will be built with plants. Despite the recognition of ecology as an essential driver of landscapes, the professionals of landscape architecture too often lack the knowledge and practical skills to create robust vegetative systems. New approaches and tools are required. This article outlines principles and methods for designing biodiverse plant systems for urban sites. Planting methods that increase species richness, functional diversity, and spatial complexity are emphasized as a way of developing more resilient plantings. Selecting species with similar evolutionary adaptions to stress, disturbance, and competition—as well as creating multi-layered compositions of diverse plant morphologies—allows designers to create compatible, long-lived plant mixes. To balance the increased visual complexity of diverse plant mixes, the article explores design techniques to make plantings more appealing to the public. The strategies explored here are based on the projects, experience, and research of Phyto Studio, a Washington, D.C. based studio. The methods build on work described in the author’s book, Planting in a Post-Wild World, an exploration of how to create designed plant communities.  相似文献   
2.
三江并流的世界自然遗产价值--生物多样性   总被引:4,自引:0,他引:4  
"三江并流"风景名胜区,是世界上生物多样性最丰富的地区之一,也是中国生物多样性最丰富的地区、全世界单位面积内生态系统类型最丰富的地区、欧亚大陆生物多样性最丰富的地区、世界最著名的植物模式标本产地、亚洲大陆多种动物分化和起源中心.可以说是北半球除沙漠、海洋景观外各类自然景观的大观园.  相似文献   
3.
建造以乡土植物为主体的园林绿地   总被引:31,自引:2,他引:31  
李树华 《中国园林》2005,21(1):47-50
指出外来植物扰乱生态平衡、破坏自然环境与人文景观以及对人们生活的严重影响等各种弊端,对园林绿化的现状以及方式方法进行了反思,提出以乡土植物为主体的园林绿地建设是城市园林绿化的惟一出路.最后,指出在进行以乡土植物为主体的城市园林绿地建设过程中存在的问题及解决办法.  相似文献   
4.
F.  A.  Y. R.  N. 《Landscape and urban planning》2004,67(1-4):195
Understanding the dynamics of biodiversity in changing agricultural landscapes is a goal for nature conservation and agricultural policies. Agriculture operates at several spatio-temporal levels from field to landscape, and induces differential response of communities according to their ecological traits. Reactions of several taxa to landscape and agricultural changes was conducted along landscape gradients in northern Brittany (France) gathering 14 sites. Landscapes ranged from fine grained areas, with a large proportion of permanent grasslands, wood and hedgerows, to coarse grained ones dominated by crops. Response of communities were either loss of species along the gradient (as for Diptera Chironomidae and Empididae), replacement (Coleoptera Carabidae) and no change in species composition (small mammals). In this paper, we present why these taxa react in such different ways according to their life history traits, their mobility patterns and to which parameters of landscape structure or agriculture intensification they are sensitive. Density of hedgerow networks, and permeability of individual hedgerows determine the spatial distribution of adults Diptera according to their flying ability. Mean body size of carabid beetles significantly decreases along the gradient of agricultural intensification, small species adapted to disturbance replacing large ones that are characteristic of stable habitats. The same small mammal species are found all along the two gradients, but their relative abundance is linked to the importance of crops versus more stable habitats in the landscape.We concluded that species survival in those fine grained agricultural landscapes depends on processes operating at the site scale and defining habitat quality, and processes operating at the landscape and/or metapopulation scale such as landscape modifications in connectivity and habitat availability.  相似文献   
5.
The biodiversity and distribution of testate amoebae in the Middle Ob flood plain soils have been studied. The biodiversity of Testacea in the soils consists of 83 species and varieties from 12 families. The population of Testacea in flood plain habitats is rich in water forms, especially in the flood plain part of the catena, because of annual floods. The study showed that the density of Testacea in the forest plots is approximately 10 times higher than in the meadow ones. The species diversity of Testacea in the meadows of the flood plain includes 40 species and varieties. It was found that there is an enrichment of the fauna of Testacea in the flood plain meadows with water forms and a decrease in the population of Testacea in the soil according to the depth. The decrease in the diversity and number down the soil profile is related to the decrease in the amount of the oxygen available and general induration of soil. On the whole, the population composition of Testacea in the soils of the pine forest consists of typical representatives of humus substrates with low values of pH, small stock of humus and mineral nutrition. The soils of mature pine forests are rich in Testacea; they have a similar complex of morphological types, mainly because of the moss cover and forest litter thickness.  相似文献   
6.
城市生物多样性是城市生存与发展的基础,是实现城市生态系统可持续性的保证。本文以相关生态学理论为指导,针对广州市海珠生态城的生态恢复实际,并结合海珠生态城"以万亩果林湿地为核心,打造具有岭南水乡魅力的花城、水城、绿城特色生态城市样板区"的总体定位,提出了该区域的生物多样性恢复目标和规划思路,并重点围绕湿地生境分区、栖息地修复、水环境改善、恢复物种筛选、区域生物多样性构建等方面进行了探讨,建立了海珠生态城湿地生物多样性恢复规划策略。  相似文献   
7.
Advances in computing power and infrastructure, increases in the number and size of ecological and environmental datasets, and the number and type of data collection methods, are revolutionizing the field of Ecology. To integrate these advances, virtual laboratories offer a unique tool to facilitate, expedite, and accelerate research into the impacts of climate change on biodiversity. We introduce the uniquely cloud-based Biodiversity and Climate Change Virtual Laboratory (BCCVL), which provides access to numerous species distribution modelling tools; a large and growing collection of biological, climate, and other environmental datasets; and a variety of experiment types to conduct research into the impact of climate change on biodiversity.Users can upload and share datasets, potentially increasing collaboration, cross-fertilisation of ideas, and innovation among the user community. Feedback confirms that the BCCVL's goals of lowering the technical requirements for species distribution modelling, and reducing time spent on such research, are being met.  相似文献   
8.
Knowledge of the nutrient content of foods is fundamental for virtually all nutrition-related projects, programmes and policies. Low quality compositional data may lead to inappropriate policies and funds spent unnecessarily. Existing food composition tables (FCT) for most West African countries date back to 1960 and 1970 and contain in general few foods and components without documentation. As a result of the recommendations by the Economic Community of West African States (ECOWAS) Nutrition forum and other high level meetings, FAO/INFOODS, WAHO/ECOWAS and Bioversity International developed the West African FCT. It contains 472 foods and 28 components. Emphasis was given to include data on food biodiversity by incorporating cultivars/varieties and underutilized foods. The West African FCT enables users to address diet-related health problems, strengthen local development, enhance trade and promote biodiversity. In addition it contributes to poverty alleviation in both rural and urban areas. The FCT needs to be updated regularly and it is the most recent example of INFOODS for regional food composition activities.  相似文献   
9.
10.
The type of land cover adjacent to hedges has been shown to influence the species composition of the ground flora. An assessment of the contribution of hedge networks to the biodiversity of landscapes therefore requires information on the relative lengths of hedge associated with different land covers. In the River Tyne catchment, Northern England, the association between hedges and land cover types differed between four landscapes. Overall, the greatest length of hedge was adjacent to arable crops, improved grasslands and roads. Hedges next to improved grassland and roads were the most species-rich, while those adjacent to arable crops were the least species-rich. Species which were common adjacent to arable crops were also common adjacent to other land covers. Hedges adjacent to improved grassland, roads and semi-natural broadleaved woodland supported species which were not common elsewhere in the hedge network. It was also found that hedges with different land cover on each side supported different floras on each side. When planning landscape-scale surveys of hedge biodiversity, it is important to survey both sides of hedges, and sampling should be stratified to include hedges adjacent to the different types of land cover present.  相似文献   
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