基于TM影像的哈尔滨市主城区绿地降温作用研究

Cooling Effect of Green Patche Based on TM Image in Harbin Downtown City

选取2001年、2005年、2013年和2015年的4期同季TM影像为数据源,利用单窗算法反演哈尔滨市主城区地表温度,以SPOT影像为数据源提取30块城市绿地斑块,将地温空间格局与城市绿地斑块进行空间耦合分析,以揭示绿地对城市热岛地温格局的干扰影响。结果表明:从空间上看,哈尔滨市主城区热岛效应显著,主城区分布着大面积高温区和次高温区,极高温区则呈点状、面状或带状孤岛型分布特点;从动态上看,城市热岛的空间格局呈现从城市中心的老城区逐渐向外围新开发建设区域扩展的特点。绿地斑块内部平均温度除与自身特征有关外,还与其空间布局和周边景观格局相关。绿地斑块降温程度和降温范围与绿地斑块面积呈正相关关系,与绿地斑块形状指数呈负相关关系,绿地降温范围与绿地斑块周长呈正相关关系。当绿地斑块面积为0.055 km^2时,绿地斑块对周边温度的降温效率较好,当绿地斑块面积在0.070 km^2时,绿地斑块对周边降温的面积效率较好。

In this study, four years TM images(2001, 2005, 2013 and 2015) were selected as the data and the single window algorithm was employed to study the surface temperature of Harbin downtown city. 30 pieces urban green patches were extracted by using SPOT image. Surface temperature spatial pattern and urban green patches coupling relationship were analyzed, which revealed green patches have an interference effect on the surface temperature spatial pattern of the urban heat island. The results show that: Spatially, the heat island effect was significant in Harbin downtown city, the large area of high temperature region and second-rate high temperature region were distribution in downtown, and extremely high temperature region have point, planar or ribbon distribution characteristics. The urban heat island presents gradually from the old town to the new development and construction characteristics of regional extension from the dynamic. It indicated that the inner average temperature of green patches is associated with its own characteristics, and it have a certain relationship with the space layout and the surrounding landscape pattern. Green patches cooling level and green patches cooling range are positively correlated relationship with green patches area. Green patches cooling level and green patches cooling range are negatively correlated relationship with green patches shape index. Green patches cooling range are positively correlated relationship with green patches perimeter. When green patches area was 0.055 km^2, make green patches for cooling efficiency of the surrounding temperature is better; When green patches area was 0.070 km^2, make green patches for area efficiency of the surrounding cooling is better.