Soil temperature reflects the impact of local factors, such as the vegetation, soil, and atmosphere of a region. Therefore, it is important to understand the regional variation of soil temperature. However, given the lack of observations with adequate spatial and/or temporal coverage, it is often difficult to use observational data to study the regional variation. Based on the observational data from Nanchang and Ganzhou stations and ERA-Interim/Land reanalysis data, this study analyzed the spatiotemporal distribution characteristics of soil temperature over Poyang Lake Basin. Four soil depths were examined, 0–7, 7–28, 28–100, and 100–289 cm, recorded as ST1, ST2, ST3, and ST4, respectively. The results showed close correlations between observation data and reanalysis data at different depths. Reanalysis data could reproduce the main spatiotemporal distributions of soil temperature over the Poyang Lake Basin but generally underestimated their magnitudes. Temporally, there was a clear warming trend in the basin. Seasonally, the temperature increase was the most rapid in spring and the slowest in summer, except for ST4, which increased the fastest in spring and the slowest in winter. The temperature increase was faster for ST1 than the other depths. The warming trend was almost the same for ST2, ST3, and ST4. An abrupt change of annual soil temperature at all depths occurred in 1997, and annual soil temperatures at all depths were abnormally low in 1984. Spatially, annual soil temperature decreased with latitude, except for the summer ST1. Because of the high temperature and precipitation in summer, the ST1 values were higher around the lake and the river. The climatic trend of soil temperature generally increased from south to north, which was opposite to the distribution of soil temperature. These findings provide a basis for understanding and assessing the variation of soil temperature in the Poyang Lake Basin.

中文翻译：

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Po阳湖流域土壤温度数据评估与分析

土壤温度反映了当地因素的影响，例如某个地区的植被，土壤和大气。因此，了解土壤温度的区域变化非常重要。但是，由于缺乏具有足够空间和/或时间覆盖范围的观测资料，因此通常难以使​​用观测数据来研究区域变化。基于南昌，赣州两地的观测资料和ERA-Interim / Land再分析资料，对analyzed阳湖流域土壤温度的时空分布特征进行了分析。检查了四个土壤深度，分别为ST1，ST2，ST3和ST4，分别为0-7、7-28、28-100和100-289 cm。结果表明，不同深度的观测数据与再分析数据之间具有密切的相关性。再分析数据可以再现re阳湖流域土壤温度的主要时空分布，但总体上低估了它们的大小。盆地暂时有明显的变暖趋势。季节性上，春季的增温最快，夏季最慢，ST4除外，春季的最快，冬季最慢。ST1的温度上升速度快于其他深度。ST2，ST3和ST4的变暖趋势几乎相同。在1997年，所有深度的年土壤温度均发生突然变化，并且在1984年，所有深度的年土壤温度均异常低。在空间上，除夏季ST1以外，年土壤温度均随纬度下降。由于夏季高温和降水，湖泊和河流周围的ST1值较高。土壤温度的气候趋势总体上是从南向北升高的，这与土壤温度的分布相反。这些发现为了解和评估the阳湖流域土壤温度的变化提供了基础。