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201.
Nodes,networks, and MUMs: Preserving diversity at all scales 总被引:14,自引:0,他引:14
The present focus of practical conservation efforts is limited in scope. This narrowness results in an inability to evaluate and manage phenomena that operate at large spatiotemporal scales. Whereas real ecological phenomena function in a space-time mosaic across a full hierarchy of biological entities and processes, current conservation strategies address a limited spectrum of this complexity. Conservation typically is static (time-limited), concentrates on the habitat content rather than the landscape context of protected areas, evaluates relatively homogeneous communities instead of heterogeneous landscapes, and directs attention to particular species populations and/or the aggregate statistic of species diversity. Insufficient attention has been given to broad ecological patterns and processes and to the conservation of species in natural relative abundance patterns (native diversity).The authors present a conceptual scheme that evaluates not only habitat content within protected areas, but also the landscape context in which each preserve exists. Nodes of concentrated ecological value exist in each landscape at all levels in the biological hierarchy. Integration of these high-quality nodes into a functional network is possible through the establishment of a system of interconnected multiple-use modules (MUMs). The MUM network protects and buffers important ecological entities and phenomena, while encouraging movement of individuals, species, nutrients, energy, and even habitat patches across space and time. An example is presented for the southeastern USA (south Georgia-north Florida), that uses riparian and coastal corridors to interconnect existing protected areas. This scheme will facilitate reintroduction and preservation of wide-ranging species such as the Florida panther, and help reconcile species-level and ecosystem-level conservation approaches. 相似文献
202.
Robert Tregay 《Journal of Environmental Planning and Management》1984,27(2):59-62
Around 1970 a quiet revolution occurred in several European countries involving the use of naturalistic design approaches and ecological principles in the design and management of urban green spaces. The objective was to bring the qualities of nature into peoples’ daily lives and provide a richer external living environment. Parallel programmes of community participation and environmental education were involved. Successful projects in Holland, Sweden and Britain are described. These indicate that despoiled urban and urban‐fringe land can be quickly and economically transformed into green environments which are attractive for living and commercial investment. A reorganisation of Local Authority landscape resources is recommended. 相似文献
203.
Anne R. Beer 《Journal of Environmental Planning and Management》1984,27(2):63-68
The lack of any particular character in much new low‐rise housing is seen as resulting in the lack of attention paid to the detailing of space between buildings. The landscape architect's role in overcoming “placelessness” is considered, and the information needs of designers is discussed. The paper also offers some notes for the designer on user needs. 相似文献
204.
给出了乘积代数的定义,讨论了其性质,并建立了乘积代数的度量,对逻辑度量空间的结构及其性质进行了讨论,得到了一些好的结果. 相似文献
205.
How does agricultural intensification modulate changes in plant community composition? 总被引:1,自引:0,他引:1
Laura José-María José M. Blanco-MorenoLaura Armengot F. Xavier Sans 《Agriculture, ecosystems & environment》2011,145(1):77-84
Agricultural intensification, at local and landscape scales, has caused a decrease in plant diversity and changes in species composition in cereal fields. To better understand the role of landscape complexity and farming systems in shaping plant assemblages, it is of interest to focus on functional traits rather than on floristic composition, which may help to highlight trends in vegetation patterns. We analysed the relative abundance of various functional attributes (different life forms, growth forms, wind-pollinated species and wind-dispersed species) at three contrasted field positions (boundary, edge and centre) of 29 organic and 29 conventional cereal fields distributed in 15 agrarian localities of NE Spain. Agricultural intensification affected the biological attributes of the vegetation in dryland Mediterranean cereal fields; local factors (farming system and position) had a more prominent role in affecting plant functional composition than the surrounding landscape. Local factors were important for life form distribution, growth form and pollination type, whereas landscape complexity mainly affected the proportion of wind-dispersed species. Therefore, depending on the objective of the study, it is important to select functional attributes sensitive to the different scales of agricultural intensification, especially because landscape complexity and land-use intensity are commonly related. 相似文献
206.
70 beaches in Wales, UK, were investigated with regard to the quality of beach scenery using video panoramas. Beaches were
given a score from zero to 20 by a panel of 24 coastal managers (National Park and Heritage Coast Wardens, etc.) and 42 final
year Degree or Master of Science students specializing in environmental sciences. Mean scores of coastal managers ranged from
16.1 (Broadhaven, S. Pembrokeshire; 80%) to 3.8 (Prestatyn, North Wales; 19%), while scores of students ranged from 16.0 (Barafundle,
S. Pembrokeshire; 80%) to 6.1 (Trecco Bay, Porthcawl; 31%). Wave height, number of people present on the beach and position
on the final videotape did not have significant effects on mean scores generated by either group. With both groups a strong
preference was observed for undeveloped beaches over those where anthropogenic structures were prominent (p=0.00), but beach commercialization level had an independent effect only on scores from the student group (p=0.02). Cloud cover at time of filming had a significant effect (p=0.00) on scoring, so a correction was applied for final score calculation and ranking. The findings contribute to management
of coastal aesthetic resources by providing a quantitative evaluation scheme. It is proposed to use these scores for beach
scenery/aesthetic quality in a novel, comprehensive beach rating system. 相似文献
207.
Habitat loss and increasing landscape fragmentation are known to be key forces driving the ongoing loss of plant species diversity. While the combined effects of increasing isolation and decreasing population size have been studied intensively; it is less understood how plant population performance in heterogeneous landscapes is affected by changes in fragmentation alone. 相似文献
208.
城市景观河流夏季污染状况及营养水平动态分析--以天津市津河为例 总被引:4,自引:0,他引:4
以CODMn、氨氮、总氮、总磷和叶绿素a等为主要指标。对天津市一条典型的景观河流——津河进行了调查分析。结果表明,津河水质介于地表水环境标准(GB3838—2002)的Ⅳ和Ⅴ类之间,营养状态为重富营养。且在多个采样点出现蓝藻水华。水体中的各项指标的变化趋势为,CODMn与叶绿素a都是在7月达到最高,随后逐渐降低。总溶解性氮夏季变化曲线呈倒“S’形。7月最低。8月最高。河道上游总溶解性磷一直比较稳定,而下游在8月上旬急剧升高。藻类演替过程大致为粉末微囊藻-皮状席藻-多种蓝藻。与改造之初相比。水质状况有所改善。 相似文献
209.
210.
人类文明的发展,不断地在改变地球的生态环境,我们赖以生存的环境正在逐渐恶化,在城市中生活的人们远离了自然,生活环境已经不再健康,雾霾、水污染以及绿化的减少,都严重影响着人类自身的发展。在意识到环境对人类社会发展的重要性之后,人们开始重视城市环境的改造,引入原生态环境景观,希望获得人类与自然的和谐与平衡,在这样的背景下城市公园的概念受到了广泛的关注,城市公园的景观设计开始追求原生态,综合考虑了对原生态环境的保护和利用,不断完善城市公园的设计,发挥原有自然环境的作用,让人工设计与自然天成融为一体,打造城市中心的绿肺,改善城市生态环境,维护人类社会生产生活与自然环境的平衡,为人类建设更为宜居的生活环境。 相似文献