广州华侨新村低密度住宅区庭院的树木和景观研究*

对广州华侨新村低密度住宅区庭院树木的组成、结构、空间格局、树木与生境的关系,以及私人庭院树木与公共绿地的不同特点进行了研究。结果表明:华侨新村庭院树木的种类多样性很高,共有114个树种。与广州城市行道树相比,华侨新村的乡土树种和果树比例较高。在调查的树木中84.75%的树木没有结构损伤现象,只有1.5%的树木生长较差。私人庭院内的树种较为分散,有45种树木为每个庭院仅一棵的单生种,有67.1%的庭院其树种在5种或以上。树木在街道的空间分布则有相对集中的趋势。庭院的大小是影响树木生长的重要条件,在有限空间的庭院内种植过多的树木是造成树木和环境关系紧张的重要原因。

TREES AND LANDSCAPE OF THE HOUSE GARDENSIN A LOW DENSITY RESIDENTIAL QUARTER OFHUAQIAO XINCUN OF GUANGZHOU

Many private trees have been planted in the house gardens of a low density residential quarter of Huaqiao Xincun of Guangzhou. The study deals with tree composition, structure, spacial pattern, and tree-habitat relationship. A survey was conducted in five main streets of the area. The 165 house gardens with 1409 trees were studied in detail. Some results were compared with those of a previous local street-tree survey. It is shown in study that:species diversity of trees was surprisingly high and tree composition was made up of 114 species. The ratios of local species and fruit trees in the house agrdens were much greater than those in local street tress. At present, most of trees are in range between 3m and 9m. However, potential high of 21 species is more than 20m. Most of trees were cared for and only 15.5% of trees was found in structural damage. In five streets only 4.2% of house gardens had no tree and more than 80% house gardens had 5 or more trees. The gardens had a relatively high species diversity and 45 species occurred as solitary specimen (one tree per garden). In house gardens with trees, 73% of house gardens had solitary specimen and 67.1% of house gardens had five or more species. Space distribution of trees by streets had a relative congregation pattern. The top 10 species of trees occurred in all survey streets and also had a great street aggregation index. This means that they cover most of the study area. Garden size was in important factor for treen growth. It was a key problem that tree density was too high and niches were limited. Trees and landscape in house gardens of Huaqiao Xncun are good examples for the low density residential quarters in other tropical and subtropical areas.