Fig. 4(D) shows that the Prop_Total

图 4（D）表明，在较高发展水平的城市中，AS 和树木的 Prop_Total 明显较高。此外，值得注意的是，在超一线城市中，AS的AI相对较低（图4（E）），而树木和草地的AI较高，这表明已经实施了有针对性的植被种植。这些地区，要避免城市建设过于密集。<br>然而，发达城市的平均 LST 仍然高于其他城市（图 4（F））。这主要归因于拥挤的人口和<br>导致高热量排放的各种人为活动，例如工业生产、家庭排放和商业贸易（贾和赵，2019）。<br>35个主要城市内沿AS比例梯度的Veg（树木/草地）比例和对应的LST如图5所示。可以观察到，随着AS比例的增加，树木的比例大部分<br>城市草地呈非线性下降，而在一些城市（如CC、HH和SJZ）则呈线性下降。但是，对于一些东南沿海城市，如广州、香港、杭州、新泽西、深圳、苏州、WX 和 YT，草原曲线在一些<br>被 10-30% AS 覆盖的地区略有上升，这可能是城市规划和管理的结果。另一方面，大部分城市（除了HZ、TJ、UQ、XN）的LST与AS的比例呈线性正相关关系。

Fig. 4(D) shows that the Prop_Total of AS and trees are obviously higher in the cities at higher development levels. Moreover, it is worth noting that, in the super first-tier cities, the AI of AS isrelatively low (Fig. 4(E)), whereas that of trees and grassland is high, which indicates that targeted vegetation planting has been implemented in these areas, to avoid overly dense urban construction.However, the mean LST of the developed cities is still higher than that of the other cities (Fig. 4(F)). This can be mainly attributed to the crowded population and various anthropogenicactivities that lead to high heat emissions, such as industrial production,domestic discharge, and commercial trade (Jia and Zhao,2019).The proportion of Veg (trees/grassland) and the corresponding LST along the proportion gradients of AS inside the 35 major cities are shown in Fig. 5. It can be observed that, with the increase of the proportion of AS, the proportion of trees and grassland in mostcities shows a non-linear decrease, while in some cities (e.g., CC,HH, and SJZ) a linear decline can be seen. However, for some southeast coastal cities, e.g., GZ, HK, HZ, NJ, SZ, SuZ, WX, and YT, the curve for grassland shows a slight rise in some areas that arecovered by 10e30% AS, which may be the result of urban planning and management. On the other hand, the LST of most cities (except HZ, TJ, UQ, XN) shows a linear positive relationship with the proportion of AS.<br>

图4(D)显示，在发展水平较高的城市，AS和树木的Prop_Total明显较高。而且值得注意的是，在超一线城市中，AS的AI相对较低(图4(E))，而树木和草地的AI较高，这说明这些地区已经实施了有针对性的植被种植，避免城市建设过于密集。然而，发达城市的平均LST仍高于其他城市(图4(F))。这主要归因于人口拥挤和各种人为因素导致高热排放的活动，如工业生产、国内排放和商业贸易(贾和赵，2019年)。图5显示了35个主要城市中沿砷比例梯度的Veg(树木/草地)比例和相应的LST。可以观察到，随着砷比例的增加，树木和草地的比例最多城市呈非线性下降，而在一些城市(如CC、HH和SJZ)可以看到线性下降。然而，对于一些东南沿海城市，例如GZ、香港、惠州、新泽西、深圳、苏州、WX和YT，草原曲线显示在一些地区略有上升，这些地区是由10e30% AS覆盖，这可能是城市规划和管理的结果。另一方面，大部分城市的LST(除了HZ、TJ、UQ、XN)与AS的比例呈线性正相关。