荒漠草原灰钙土与风沙土水分时空特征 postprint

Abstract: Due to the interference from human activities and natural factors, the primary sierozem area in theNingxia desert steppe has gradually shrunk due to long-term desertification and formed island patches within thesurrounding aeolian soil. To reveal the spatiotemporal characteristics of soil moisture after sierozemdesertification, a comparative study was carried out between the large (200-300 m2), medium (approximately 100m2), and small (approximately 50 m2) sierozem patches and the surrounding aeolian soil in Wanjigou Village,Yanchi County, Ningxia, during the growing season (May to October from 2017 to 2019). The uniform rainfallpattern in 2017 led to the highest annual average soil moisture content. While the annual rainfall in 2018 wasslightly higher than that in 2017, it was concentrated in the spring, and there were almost no rainfall events in thesummer and autumn, resulting in a low soil moisture content throughout the year. The summer rainfall pattern in2019 resulted in the highest average soil moisture content during the summer period. The soil moisture content ofsierozem in the 0-100 cm soil layer first showed an increase and then a decrease with increases in soil depth andwas greatest in the 10-40 cm soil layer. The soil moisture content of the aeolian soil increased with soil depth,and the soil moisture content of the 0-20 cm soil layer was much lower than that of the 20-100 cm layer. Themoisture content of sierozem in the 0-20 cm soil layer was greater than that of the aeolian soil, while themoisture content of the sierozem in the 20-100 cm soil layer was significantly lower than that of the aeolian soil(except for small and medium-sized patches in 2018). There was no significant difference (P > 0.05) in the soilmoisture content of the sierozem between the different patch sizes, except that the soil moisture content of theaeolian soil surrounding the large-sized patches was significantly greater than that of the small and medium-sizedpatches (P < 0.05). The water storage of sierozem in the 0-100 cm soil layer was generally lower than that of theaeolian soil, and the variation range was smaller than that of the aeolian soil during the same period. When therainfall was <16 mm, the water in both soil types was in a consumption state. When the rainfall ranged from 16 to25 mm, the water storage capacity of the sierozem was greater than that of the aeolian soil, but when the rainfallwas >25 mm, the water storage capacity of the aeolian soil was greater than that of the sierozem. The soilmoisture content in the desert steppe was dominated by the rainfall, its distribution pattern, and soil type. Themoisture contents of the sierozem and aeolian soils differ in their profiles, as well as in response to rainfall.