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191.
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   
192.
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   
193.
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   
194.
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   
195.
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   
196.
基于2010—2015年江苏省常州市金坛区高分辨率遥感影像,综合分析了生态系统空间分布格局及其演变特征,初步揭示了生态系统的驱动力及其对生态系统格局变化的影响。结果表明,金坛区生态系统类型主要由农田、湿地、城镇构成,3者合占总面积的87. 8%; 2010年以来,金坛加快实施城市"东扩南移"战略,原有农田不断被蚕食,生态系统的聚集度、边界密度有所上升,城镇更加连片分布,城镇面积已接近2020年18 604. 7 hm~2的建设红线。  相似文献   
197.
曹玉 《环境与发展》2020,(2):190-190,192
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   
198.
A linear engineering project--i.e. a pipeline--has a potential long- and short-term impact on the environment and on the inhabitants therein. We must find better, less expensive, and less time-consuming ways to obtain information on the environment and on any modifications resulting from anthropic activity. We need scientifically sound, rapid and affordable assessment and monitoring methods. Construction companies, industries and the regulating government organisms lack the resources needed to conduct long-term basic studies of the environment. Thus there is a need to make the necessary adjustments and improvements in the environmental data considered useful for this development project. More effective and less costly methods are generally needed. We characterized the landscape of the study area, situated in the center and north-east of Argentina. Little is known of the ecology of this region and substantial research is required in order to develop sustainable uses and, at the same time, to develop methods for reducing impacts, both primary and secondary, resulting from anthropic activity in this area. Furthermore, we made an assessment of the environmental impact of the planned linear project, applying an ad hoc impact index, and we analyzed the different alternatives for a corridor, each one of these involving different sections of the territory. Among the alternative corridors considered, this study locates the most suitable ones in accordance with a selection criterion based on different environmental and conservation aspects. We selected the corridor that we considered to be the most compatible--i.e. with the least potential environmental impact--for the possible construction and operation of the linear project. This information, along with suitable measures for mitigating possible impacts, should be the basis of an environmental management plan for the design process and location of the project. We pointed out the objectivity and efficiency of this methodological approach, along with the possibility of integrating the information in order to allow for the application thereof in this type of study.  相似文献   
199.
The article describes a riverscape approach based on landscape ecology concepts, which aims at studying the multiscale relationships between the spatial pattern of stream fish habitat patches and processes depending on fish movements. A review of the literature shows that few operational methods are available to study this relationship due to multiple methodological and practical challenges inherent to underwater environments. We illustrated the approach with literature data on a cyprinid species (Barbus barbus) and an actual riverscape of the Seine River, France. We represented the underwater environment of fishes for different discharges using two-dimensional geographic information system-based maps of the resource habitat patches, defined according to activities (feeding, resting, and spawning). To quantify spatial patterns at nested levels (resource habitat patch, daily activities area, subpopulation area), we calculated their composition, configuration, complementation, and connectivity with multiple spatial analysis methods: patch metrics, moving-window analysis, and least cost modeling. The proximity index allowed us to evaluate habitat patches of relatively great value, depending on their spatial context, which contributes to the setting of preservation policies. The methods presented to delimit potential daily activities areas and subpopulation areas showed the potential gaps in the biological connectivity of the reach. These methods provided some space for action in restoration schemes.  相似文献   
200.
21世纪初的玛纳斯县域土地利用面临新的政策和技术背景,采用遥感技术对2000年和2005年玛纳斯县域人类主要活动区各类景观进行比对分析,发现研究区内耕地、城镇景观面积出现大幅增长,林地、草地景观面积显著下降,“农林”、“农草”争水、争地的矛盾逐渐激化,水资源的供需处于“紧平衡”状态,区域景观生态系统的多样性、稳定性降低。分析表明农业产业组织形式的创新和农业节水灌溉技术的突破是玛纳斯县域景观生态变化的关键因子。  相似文献   
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