The rising urban land surface temperature (LST) has undoubtedly caused an imminent threat to human habitat. Landscape patterns are among the most significant factors related to LST. However, the marginal effects and thresholds of landscape at optimal grid scale on LST within diverse local climate zones (LCZs) are poorly understood. This study employed the boosted regression trees (BRT) model to evaluate the relative influences and marginal effects of built-up, water, and green landscape metrics on LST at the optimal grid scale across various LCZs. The findings reveal that: (1) The spatial spread trend of LST closely matches the expansion trend of built-up landscapes. (2) Significant variations in average summer LST were observed among LCZs, with LCZ8 (large low-rise) exhibiting the highest temperatures and LCZ11 (dense trees) the lowest. (3) At the optimal scale of 1000 m, the DIVISION metric for water landscapes significantly influenced LCZ6 (open low-rise), LCZ8, and LCZ14 (low plants). (4) In LCZ6 and LCZ8, effective heat mitigation requires increasing water area to 50% and optimizing the water body separation index to 0.88. These findings suggest that heterogeneous landscape heat mitigation strategies should be considered across diverse LCZs in urban areas.

中文翻译：

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基于最佳景观尺度的景观对当地气候带城市地表温度的边际效应


城市地表温度（LST）的上升无疑对人类栖息地造成了迫在眉睫的威胁。景观格局是与地表温度相关的最重要因素之一。然而，人们对不同当地气候区 (LCZ) 内地表温度的最佳网格尺度景观的边际效应和阈值知之甚少。本研究采用增强回归树 (BRT) 模型来评估各个 LCZ 的最佳网格规模下建筑、水和绿色景观指标对 LST 的相对影响和边际效应。研究结果表明：（1）地表温度的空间扩展趋势与建成景观的扩张趋势密切相关。 (2) LCZ 夏季平均地表温度存在显着差异，其中 LCZ8（大型低层）温度最高，LCZ11（茂密树木）温度最低。 （3）在1000 m的最佳尺度下，水景观的DIVISION度量对LCZ6（开放式低层植物）、LCZ8和LCZ14（低矮植物）影响显着。 (4) 在LCZ6和LCZ8中，有效缓解热量需要将水域面积增加至50%，并将水体分离指数优化至0.88。这些发现表明，应在城市地区的不同 LCZ 中考虑异质景观散热策略。