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自1980年以来的全球土壤湿度动态:1980年以来的全球土壤湿度动态:数据集偏差,趋势和科学知情的选择

Ziyang Zhu¹, Meiqing Feng², Wim Cornelis³

¹State Key Laboratory of Ecological Safety and Sustainable Development in Arid Lands, Xinjiang Institute of Ecology and Geography, Chinese Academy of Sciences, Urumqi 830011, China; University of Chinese Academy of Sciences, Beijing 100049, China; Soil Physics (SoPHy), Department of Environment, Ghent University, Ghent 9000, Belgium; Xinjiang Key Laboratory of Water Cycle and Utilization in Arid Zone, Xinjiang Institute of Ecology and Geography, Chinese Academy of Sciences, Urumqi 830011, China; Ili Station for Watershed Ecosystem Research, Chinese Academy of Sciences, Xinyuan 835800, China; Tianshan Snowcover and Avalanche Observation and Research Station of Xinjiang, Chinese Academy of Sciences, Xinyuan 835800, China.

Science bulletin

|November 15, 2025

概括

全球土壤湿度显示长期略有下降,但数据集性能不同. 微波遥感产品,特别是SMAP,在土壤湿度监测中为时间动态提供了更高的准确性.

科学领域:

地球和环境科学地球和环境科学
气候科学气候科学
水文学水文学

背景情况:

土壤湿度对于气候预测,生态管理和灾害预警至关重要.
现有的多源土壤湿度数据集由于算法和观测约束而表现出时空不一致性和有限的区域适用性.

研究的目的:

统计评估23个全球表面土壤湿度数据集的性能和时空变化.
为了评估数据集在全球不同地区的适用性,根据科本气候和IPCC土地用途进行分类.

主要方法:

对跨越1980-2023年的23个全球表面土壤湿度数据集的分析,包括重新分析,陆地表面模型和微波遥感.
对992个现场站和过的483个高度代表性的站进行双重验证.
使用皮尔森相关性 (R) 和时空趋势分析进行统计性能评估.

主要成果:

从1980年到2023年,全球表面土壤湿度略有下降 (-4.30 × 10−4 m−3 m−3 a−1) 被观察到,一些数据集显示2010年后的短期湿.
大多数产品表现中等好 (R ≈ 0.5-0.7),微波遥感 (特别是SMAP) 显示出优异的时间动态捕获 (R ≈ 0.7).
空间代表性错误显著影响验证;过站改善了热带地区的验证 (平均R增加0.41).

结论:

数据集的性能各不相同,因此在水文和气候研究中需要采用以科学为基础的,针对特定应用的选择方法.
微波遥感产品在捕获时间土壤湿度动态方面表现出更高的可靠性.
解决空间代表性对于准确的土壤湿度数据集验证和应用至关重要.

关键词:

全球数据集全球数据集在现场观察观察.科学知情的选择选择.土壤水分土壤水分空间代表性空间代表性时间空间的趋势.

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