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1.
城市园林绿化现存问题、对策及其绿化植物配置原则 总被引:21,自引:4,他引:17
随着国民经济的不断发展,城市园林绿化已成为现代建设的重要内容。在归结上前城市园林绿化所存共性问题的基础上,针对城市园林绿化普遍存在的4方面问题,提出5点对策。 相似文献
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The re-emergence of indigenous forest in an urban environment, Christchurch, New Zealand 总被引:4,自引:0,他引:4
Glenn H. Stewart Maria E. Ignatieva Colin D. Meurk Richard D. Earl 《Urban Forestry & Urban Greening》2004,2(3):149-158
Christchurch, the second largest city in New Zealand is a planned city on a coastal plain on the east coast of the South Island. The birth of the city and the subsequent century of development was characterised by colonial values and tree and garden planting with familiar European species along with those from Australia, North America, and eventually all other continents. The image of an “English garden city” with classical parks of oaks and willow-lined rivers became the accepted norm and the way in which the city has been promoted to potential tourists. Gardening is one of the top two recreational activities and exotic species greatly outnumber native species in the flora and in gardens. This has had serious consequences for the highly fragmented and degraded indigenous vegetation and its co-adapted wildlife. A few hardy indigenous species continued to regenerate through this period, but since the 1970s, there has been a progressive change of attitude and interest in reclaiming the natural heritage of the city, manifest in widespread private and public planting of indigenous species and active habitat restoration. In this article we examine the indigenous and exotic shrub and tree components of the Christchurch flora as planted street trees, in domestic gardens, and in parks. We also present data on shrub and tree regeneration in parks and domestic gardens in the city. Indications are that the more sensitive, less intrusive management of urban environments, combined with the greater density of indigenous seed sources, has allowed regeneration of a wide range of indigenous species across a broad spectrum of habitats – from neglected gardens to pavement cracks to exotic plantations. This is despite the competition from the prodigious seed banks and density of exotic trees, shrubs, and ground covers and albeit minimal impacts of introduced browsing and seed eating mammals. If the present trends continue through appropriate management and facilitation, these tentative signs of native forest regeneration should eventually proliferate into a sustainable mixed origin urban forest that resurrects and preserves the natural character of the region. 相似文献
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Path analysis of spatial predictors of front-yard landscape in an anthropogenic environment 总被引:4,自引:0,他引:4
Contagious spatial patterns were shown to exist in the landscape of front-yards in street sections of Hochelaga-Maisonneuve, Montréal. Neighbour mimicry was hypothesized as the mechanism behind this pattern (Zmyslony and Gagnon 1998). To assess the role of spatial environmental factors in structuring this pattern, we carried out a path analysis on the front-yard landscape with five spatial factors: relative distance, street side, width, depth and type of front-yard. We removed all non-significant factors from our model with simple Mantel tests and untangled the common spatial component from the relationship between spatial factors and front-yard landscape with partial Mantel tests. We then used path analysis to evaluate the relative importance of all significant spatial factors in structuring front-yard landscape and to determine the r
2 (% of landscape variation explained by spatial factors). Results showed that (1) among all spatial environmental factors, distance (proximity) remained the best predictor of front-yard vegetation – distance alone explained an average of 20% of the landscape variation of a street section, (2) depth, width and type of front-yard also structured the front-yard landscape independently of distance, (3) front-yard landscape expresses greater similarity within the same side of a street section, and (4) in two street sections of Hochelaga-Maisonneuve, spatial factors predicted over 40% of the landscape variation. This suggests (1) that landscape contagion exists also in highly humanized environments and (2) that the mimicry phenomenon was induced not only by proximity, but also by similar environmental conditions in same side street sections and whole street sections. Finally, we suggest that street sections are a very useful and appropriate unit of analysis of urban ecosystems. 相似文献
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基于空间采样的城市景观格局梯度分析——以成都市中心城区为例 总被引:1,自引:0,他引:1
通过空间网格采样的格局指数在景观水平上定量并图示化分析了成都市绕城高速以内区域的城市景观格局特征和城乡景观格局差异。结果表明,成都市的圈层式发展特点能够通过空间采样的格局指数进行量化,并且不同的指数从不同的方面表现了成都市景观格局在城乡梯度上的差异。除表现景观形状特征的指数不太规则外,在城乡梯度上平均斑块面积、斑块密度、边缘密度以及聚集度均表现出逐渐上升或下降的单调变化趋势,而最大斑块指数、分割度和Shannon多样性指数均由于城乡交错带的影响表现出非单调变化趋势。 相似文献
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呼和浩特市城市现代化水平综合评价与分析 总被引:2,自引:0,他引:2
城市现代化是城市素质的综合反映,城市现代化水平评价是衡量1个城市综合竞争力的最有效方法。本文根据城市现代化的概念与内涵,构建了呼和浩特市城市现代化评价指标体系与测度模型,运用层次分析法对历年的城市现代化水平进行了综合评价与动态分析。分析表明:自1990年以来,呼和浩特市城市现代化水平呈平稳上升趋势,但总体水平仍然偏低,处于现代化的准备阶段向基本实现现代化阶段的过渡时期。 相似文献