Yan Hai, Fan Shuxin, Guo Chenxiao, Hu Jie, Dong Li
College of Landscape Architecture, Beijing Forestry University, Beijing, China; School of Landscape Architecture, Zhejiang Agriculture and Forestry University, Lin'an, Zhejiang, China.
College of Landscape Architecture, Beijing Forestry University, Beijing, China.
PLoS One. 2014 Jul 10;9(7):e102124. doi: 10.1371/journal.pone.0102124. eCollection 2014.
The effects of land cover on urban-rural and intra-urban temperature differences have been extensively documented. However, few studies have quantitatively related air temperature to land cover composition at a local scale which may be useful to guide landscape planning and design. In this study, the quantitative relationships between air temperature and land cover composition at a neighborhood scale in Beijing were investigated through a field measurement campaign and statistical analysis. The results showed that the air temperature had a significant positive correlation with the coverage of man-made surfaces, but the degree of correlation varied among different times and seasons. The different land cover types had different effects on air temperature, and also had very different spatial extent dependence: with increasing buffer zone size (from 20 to 300 m in radius), the correlation coefficient of different land cover types varied differently, and their relative impacts also varied among different times and seasons. At noon in summer, ∼ 37% of the variations in temperature were explained by the percentage tree cover, while ∼ 87% of the variations in temperature were explained by the percentage of building area and the percentage tree cover on summer night. The results emphasize the key role of tree cover in attenuating urban air temperature during daytime and nighttime in summer, further highlighting that increasing vegetation cover could be one effective way to ameliorate the urban thermal environment.
土地覆盖对城乡和城市内部温差的影响已有大量文献记载。然而，很少有研究在局部尺度上对气温与土地覆盖组成进行定量关联，而这可能有助于指导景观规划与设计。在本研究中，通过实地测量活动和统计分析，对北京邻里尺度上气温与土地覆盖组成之间的定量关系进行了调查。结果表明，气温与人工表面覆盖率呈显著正相关，但相关程度在不同时间和季节有所不同。不同的土地覆盖类型对气温的影响不同，且空间范围依赖性也有很大差异：随着缓冲区大小增加（半径从20米到300米），不同土地覆盖类型的相关系数变化不同，其相对影响在不同时间和季节也有所不同。在夏季中午，约37%的温度变化可由树木覆盖率解释，而在夏季夜间，约87%的温度变化可由建筑面积百分比和树木覆盖率解释。研究结果强调了树木覆盖在夏季白天和夜间减弱城市气温方面的关键作用，进一步突出了增加植被覆盖可能是改善城市热环境的一种有效方式。
