城市建筑格局对小气候的影响

本文以南京农业大学实验楼独特的建筑格局所形成的局部小区域为研究对象,测量了其内、外的日最高气温、日最低气温和平均气温,测定结果表明,由于实验楼的特殊建筑格局,在晴好天气实验楼内外草坪的最低气温相差4℃以上,而阴雨天温差比较小,一般在2℃以下。当西北方冷空气来临时,内外草坪温差迅速上升,并大于-4℃。正是因为这一点,使得实验楼外部草坪的最低气温低于桔树临界低温-4℃时,内部草坪温度仍旧在-4℃以上,正是因为这一点使得原来在南京不能正常生长结果的桔树在实验楼内生长非常好,也就是说小气候足以使植物物种的分布发生改变。从四个不同时间段的平均温差来看,中午14时实验楼内外温差为最高为1.7℃,夜间2时和早晨8时次之,为1.3℃,20时温差最小为0.9℃。本文的目的在于强调现代城市建筑格局对于小气候不可忽视的影响,以期引起人们对此的关注,作者对城市建筑小气候的合理利用提出了几点思考。

The Impact of the Pattern of Urban Architecture on Microclimate

This paper regards the unique building pattern of experiment building in Nanjing Agricultural University as an observation spot;meanwhile the daily maximum temperature, minimum temperature and mean temperature of the lawn inside and outside of the experiment building were measured respectively. The results indicate that because of the special building pattern, the difference in minimum temperature on sunny days is more than 4 ℃ between the building and the open space. However the difference in temperature during the cloudy and rainy days is minor, being generally less than 2 ℃. When the cold air comes in from the North, the difference in temperature often rises rapidly, this makes the daytime minimum temperature of the lawn inside the experiment building 4℃ higher than that of the open space. As the minimum temperature of the lawn outside of the experiment building reaches the critical low temperature of the orange tree at-4 ℃, the temperature of the lawn intra building still keeps at about 0℃. Just because of this reason, if we are to grow oranges under the same condition as outside of the experiment building, the oranges will not grow well;however, orange can grow very well under the same climate condition as that of the lawn inside of the experiment building. In other words, the microclimate has even caused the transformation of the distribution of the plant species. The mean differences in temperature are different at different time intervals of a day, the difference in mean temperature is the highest at 14:00h at noon, being 1.7℃;the next is at 08:00h in the morning and at 02:00h at night, being 1.3 ℃;and the lowest is at 20:00h, being 0.9 ℃. The pattern of urban architecture exerts a greatest influence on the minimum temperature in a day. The object of this paper is to emphasize the impact of the pattern of urban architecture on microclimate and to arouse public attention. Finally suggestion is given on how to rationally utilize urban buildings.