城市化进程中天津城市热岛景观格局变化分析

为了控制城市热岛的增长趋势并提出科学的政策方案,以天津市为研究对象,利用2001年—2009年的5景Landsat TM/ETM+遥感影像数据对地表亮温进行反演,并利用景观格局指数分析城市热岛在天津城市化进程中的演变特征.结果表明:随着天津城市化进程的发展,热岛景观在数量特征上体现为斑块个数减少,高等级热岛景观类型面积和单体面积均增大,热岛景观逐渐变得更加聚集化;在形态特征上,热岛景观形状指数增大,斑块形状越来越复杂;在结构特征上,热岛景观的聚合度、邻近指数和蔓延度逐渐增大,多样性指数和均匀度指数降低,热岛景观分布向不均匀、组团式发展;在空间分布上,研究区的高温组团大致分布在市区、塘沽区中东部、汉沽区西北部和大港西南部,其中以市区和塘沽区中东部2个组团为典型.利用景观指数分析城市热岛环境,可为制定有效防止热岛发展的措施提供科学依据.

Analysis of the changes of urban heat island landscape pattern in the urbanization process of Tianjin

In order to control the growth trend of urban heat island and make policy scientifically, taking Tianjin as the research object, the surface temperature were inversed using 5 scenes Landsat TM/ETM＋ remote sensing image data during 2001-2009, and the evolution characteristics of urban heat island were analyzed using the landscape pattern metrics during the urbanization process of Tianjin. The results show that with the development of urbanization in Tianjin, the plaque number of heat island landscape decreases while the class area and monomer area increase in high heat island landscape in the quantity characteristics. Heat island landscape becomes more gathered gradually. Shape index of heat island landscape increase and patch shape becomes more complicated than those before in the morphological characteristics. The aggregation degree, proximity index and CONTAG of the heat island landscape gradually increase while the diversity index and uniformity index decrease in the structure characteristics, the distribution of heat island landscape is developed to the asymmetry and group. High temperature groups in the research area are roughly distributed in urban areas, eastern Tanggu district, northwest Hangu district and southwest Dagang district in the spatial distribution, and the two groups of urban and southwest Tanggu district are typical examples. The scientific reference can be provided for preventing the development of heat island by analyzing the heat island environment using landscape metrics.