土地利用规模?结构?形态演变对城市热环境的影响——以西安市主城区为例

土地利用变化与城市热环境关系紧密。以西安市为例，采用遥感影像数据，从规模?结构?形态对土地利用变化进行了分析，同时，对西安市热环境变化特征进行了阐释，在此基础上，对土地利用规模、结构和形态变化与热环境变化关系进行了系统分析，揭示土地利用变化对城市热环境的影响。结果如下：① 2000—2016年，随着建设用地的增长，西安市平均地表温度呈上升趋势，耕地与建设用地面积占比变化与地表温度变化呈正相关性，林草地与水域面积占比变化与地表温度变化呈负相关性；② 林草地、水域的斑块优势度越大，形状越复杂，集聚度越高，越有利于改善热环境，而耕地和建设用地的斑块景观优势度大、集聚度高，则会导致地表温度升高和热环境恶化；③ 集聚度和连通度高的大斑块林草地和水域具有更突出的降温效果，相反，高度集聚的建设用地形成的不透水面具有更强的升温效果。可为从土地利用视角改善城市热环境提供参考依据。

Study on the Influence of Land Use Evolution of Scale,Structure and Pattern on Urban Thermal Environment: A Case Study of Xi’an

Land use change is closely related to urban thermal environment. This paper uses remote sensing image data to interpret and invert the land use types and land surface temperature (LST) of Xi’an in 2000, 2008 and 2016 respectively, and analyzes land use changes from scale, structure, and pattern. Meanwhile, the characteristics of thermal environment changes in Xi′an are explained. On this basis, the relationship between land use changes and thermal environment changes is systematically analyzed to reveal the impact of land use changes on the urban thermal environment. The results are as follows: 1) From 2000 to 2016, with the increase of construction land, the average LST of Xi’an City showed a rising trend. The proportion of cultivated land and construction land was positively correlated with the change of land surface temperature, while the proportion of forest and grass land and water area was negatively correlated with the change of land surface temperature. 2) The larger the patch dominance degree, the more complex the shape and the higher the aggregation degree of forest, grass and water, the more conducive to improving the thermal environment, while the larger the patch dominance degree and the higher the aggregation degree of farmland and construction land, the higher the LST and the thermal environment deterioration. 3) The large patch forest grassland and water area with high degree of agglomeration and connectivity have a more prominent cooling effect, on the contrary, the impervious water surface formed by the construction land with high concentration has a stronger warming effect. This study can provide reference for improving urban thermal environment from the perspective of land use.