Arid Zone Research ›› 2023, Vol. 40 ›› Issue (10): 1625-1636.doi: 10.13866/j.azr.2023.10.09

• Land and Water Resources • Previous Articles     Next Articles

Spatiotemporal characteristics of sierozem and aeolian soil moisture levels in a desert steppe

YANG Shuangqi1,2,3(),SONG Naiping1,2,3(),WANG Xing1,2,3,CHEN Xiaoying4,CHANG Daoqin1,2,3   

  1. 1. College of Ecological Environment, Ningxia University, Yinchuan 750021, Ningxia, China
    2. Breeding Base for State Key Laboratory of Land Degradation and Ecological Restoration in Northwestern China, Ningxia University, Yinchuan 750021, Ningxia, China
    3. Key Laboratory for Restoration and Reconstruction of Degraded Ecosystem in Northwestern China of Ministry of Education, Ningxia University, Yinchuan 750021, Ningxia, China
    4. School of Agricultural, Ningxia University, Yinchuan 750021, Ningxia, China
  • Received:2023-02-13 Revised:2023-04-22 Online:2023-10-15 Published:2023-11-01

Abstract:

Due to the interference from human activities and natural factors, the primary sierozem area in the Ningxia desert steppe has gradually shrunk due to long-term desertification and formed island patches within the surrounding aeolian soil. To reveal the spatiotemporal characteristics of soil moisture after sierozem desertification, a comparative study was carried out between the large (200-300 m2), medium (approximately 100 m2), 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 rainfall pattern in 2017 led to the highest annual average soil moisture content. While the annual rainfall in 2018 was slightly higher than that in 2017, it was concentrated in the spring, and there were almost no rainfall events in the summer and autumn, resulting in a low soil moisture content throughout the year. The summer rainfall pattern in 2019 resulted in the highest average soil moisture content during the summer period. The soil moisture content of sierozem in the 0-100 cm soil layer first showed an increase and then a decrease with increases in soil depth and was 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. The moisture content of sierozem in the 0-20 cm soil layer was greater than that of the aeolian soil, while the moisture 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 soil moisture content of the sierozem between the different patch sizes, except that the soil moisture content of the aeolian soil surrounding the large-sized patches was significantly greater than that of the small and medium-sized patches (P < 0.05). The water storage of sierozem in the 0-100 cm soil layer was generally lower than that of the aeolian soil, and the variation range was smaller than that of the aeolian soil during the same period. When the rainfall was <16 mm, the water in both soil types was in a consumption state. When the rainfall ranged from 16 to 25 mm, the water storage capacity of the sierozem was greater than that of the aeolian soil, but when the rainfall was >25 mm, the water storage capacity of the aeolian soil was greater than that of the sierozem. The soil moisture content in the desert steppe was dominated by the rainfall, its distribution pattern, and soil type. The moisture contents of the sierozem and aeolian soils differ in their profiles, as well as in response to rainfall.

Key words: desert steppe, soil moisture, soil type, precipitation changes, soil water storage