关中地区是陕西省主要的农业生产基地，但频发的旱灾严重阻碍了社会经济的发展。土壤湿度作为反映旱灾的一个重要指标，进行土壤湿度对气候因子响应的研究，可为科学认识干旱规律及制定政策提供依据。以关中地区为研究区，采用2001—2020年的MODIS-NDVI与MODIS-LST长时间序列数据，构建了关中地区地表土壤干湿状况（TVDI）特征空间，采用线性趋势法、相关性分析、敏感性分析等统计方法对关中地区土壤干湿状况的空间分布特征及其对气候的响应进行分析。结果表明：（1）TVDI能够较为准确的反演出关中地区的土壤湿度状况。近20 a来，关中地区土壤干湿状况存在变干趋势；其中，春季最旱、冬季次之。（2）土壤干湿状况的空间分布存在明显的空间异质性，整体上呈现西南向东北干旱递增的趋势。（3）土壤干湿状况与降水和气温存在相关性。与降水呈正相关关系，随着降水量增加，土壤湿度增加；与气温呈负相关关系，随着气温升高，土壤湿度降低。（4）降水对土壤干湿状况的敏感性较高，而气温对土壤干湿状况的变化程度起着较大的影响。降水决定了土壤湿度值的增加或减少的方向，而气温则决定了增加或减少的程度。土壤干湿状况是一个综合指标，其值受降水和气温的影响。降水是决定增减趋势的主要因素，而气温则决定了增减的幅度。因此，仅研究气温和降水的影响时，降水是控制土壤干湿状况增减趋势的主要因素，而气温则调节了这种增减的幅度。

The Guanzhong region serves as the main agricultural production base in Shaanxi Province. However, frequent droughts severely impede socioeconomic development in the area. Soil moisture, a vital drought indicator, can offer valuable insights into understanding drought laws and formulating policies to address them by studying the response of soil moisture to climate factors. Within the Guanzhong region, long-term MODIS-NDVI and MODIS-LST series data from 2001 to 2020 were used to establish the characteristic spatial distribution of surface soil moisture and dryness (TVDI). The linear trend method, correlation analysis, sensitivity analysis, and other mathematical statistical methods were used to scrutinize the spatial distribution patterns of soil moisture and dryness in response to climate conditions. Key results are as follows: (1) TVDI can accurately reflect soil moisture status in the Guanzhong region, revealing a trend of both soil drying and wetting over the past two decades, with spring being the driest, followed by winter. (2) There is significant spatial heterogeneity in soil moisture distribution and dryness, with an overall trend of increasing drought from the southwest to the northeast. (3) Soil moisture exhibits correlations with precipitation and temperature: it is positively correlated with precipitation (as precipitation increases, soil moisture increases) and negatively correlated with temperature (as temperature increases, soil moisture decreases). (4) Precipitation has a high sensitivity to soil moisture and dryness, while temperature significantly impacts the degree of changes in soil moisture and dryness. Precipitation determines the direction in which soil moisture values increase or decrease, whereas temperature determines the degree of increase or decrease. Soil dryness and wetness act as comprehensive indicators, influenced by both precipitation and temperature. Precipitation predominantly determines the trend of value increase or decrease, while temperature determines the magnitude of the increase or decrease. Hence, when studying the impacts of temperature and precipitation, precipitation emerges as the main factor controlling soil moisture and dryness trends, while temperature regulates the extent of these changes.