欢迎访问《草业学报》官方网站,今天是 分享到:

草业学报 ›› 2024, Vol. 33 ›› Issue (4): 22-34.DOI: 10.11686/cyxb2023209

• 研究论文 • 上一篇    下一篇

荒漠草原灌丛转变过程土壤水分亏缺空间特征及影响因素

赵亚楠1,2(), 王红梅1,3(), 李志丽1, 张振杰1, 陈彦硕1, 苏荣霞1   

  1. 1.宁夏大学林业与草业学院,宁夏 银川 750021
    2.中国科学院地理科学与资源研究所,北京 100101
    3.宁夏大学西北退化生态系统恢复与重建教育部重点实验室,宁夏 银川 750021
  • 收稿日期:2023-06-23 修回日期:2023-07-11 出版日期:2024-04-20 发布日期:2024-01-15
  • 通讯作者: 王红梅
  • 作者简介:E-mail: whm_826@nxu.edu.cn
    赵亚楠(1995-),男,陕西延安人,特别研究助理,博士。E-mail: zhaoyanan@igsnrr.ac.cn
  • 基金资助:
    国家自然科学基金(31860677);宁夏高等学校一流学科建设项目(NXYLXK2017A01)

Responses of spatial pattern and driving factors for soil water deficit of desert grassland-shrubland transition sites

Ya-nan ZHAO1,2(), Hong-mei WANG1,3(), Zhi-li LI1, Zhen-jie ZHANG1, Yan-shuo CHEN1, Rong-xia SU1   

  1. 1.College of Forestry and Prataculture,Ningxia University,Yinchuan 750021,China
    2.Institute of Geographic Sciences and Natural Resources Research,Chinese Academy of Sciences,Beijing 100101,China
    3.Key Laboratory of Restoration and Reconstruction of Degraded Ecosystems in Northwestern China of Ministry of Education,Ningxia University,Yinchuan 750021,China
  • Received:2023-06-23 Revised:2023-07-11 Online:2024-04-20 Published:2024-01-15
  • Contact: Hong-mei WANG

摘要:

草地灌丛化对生态系统结构、功能与服务产生重要影响,目前已经认识到其对土壤水分的负面影响,但还缺乏其在区域尺度的定量评价及其驱动机制研究。在宁夏荒漠草原选取43块成对样地(即荒漠草地和灌丛地),引入样地土壤水分相对亏缺指数(PCSWDI)评价荒漠草原向灌丛转变后土壤水分亏缺空间格局现状及其驱动因子。结果表明:荒漠草原转变为灌丛后0~100 cm和100~200 cm土壤含水量分别显著下降了27.80%和57.92%,0~100 cm灌丛地的PCSWDI显著低于荒漠草地,表明0~100 cm灌丛地目前不存在土壤水分亏缺现象。地统计学分析表明,荒漠草地和灌丛地的0~100 cm土壤水分相对亏缺指数的结构方差比分别为94.73%和95.29%,均属于强空间自相关,主要受结构性因子控制。此外,地理探测器的因子探测发现0~100 cm土壤储水量、坡向和田间持水量是影响灌丛地土壤水分相对亏缺指数的主导因子;交互探测表明,灌丛地0~100 cm土壤水分相对亏缺指数空间分异是多因子共同作用的结果。尽管分析得到0~100 cm灌丛地不存在土壤水分亏缺,但100~200 cm土壤含水量显著下降已经预示了深层土壤水分的消耗。因此,干旱半干旱地区的植被恢复必须考虑其植被承载力和水分阈值,基于自然的解决方案可能是未来植被恢复的主流思路。

关键词: 荒漠草原, 人为灌丛化, 土壤水分, 地理探测器, 样地土壤水分相对亏缺指数

Abstract:

Shrub encroachment has an important impact on ecosystem structure, function and services, and its adverse impact on soil water has been recognized, but there is still a lack of quantitative assessment and research into its driving mechanisms at a regional scale. In the Ningxia desert steppe, 43 paired sample sites of desert grassland and of shrubland were selected, and a ‘plot compared soil water deficit index’ (PCSWDI) was introduced to evaluate the spatial pattern of soil water deficit and its drivers after the transition from desert steppe to shrubland. Results showed that the soil water content of 0-100 cm and 100-200 cm strata decreased significantly by 27.80% and 57.92%, respectively, after the transition from desert grassland to shrubland. Also, the PCSWDI of shrubland from 0-100 cm was significantly lower than that of desert grassland, indicating that there is no soil water deficit in the 0-100 cm layer of shrubland. Geostatistical analysis showed that the structural variance ratios of the PCSWDI of desert grassland and shrubland were 94.73% and 95.29%, respectively, which indicate strong spatial autocorrelation and were mainly controlled by structural factors. Furthermore, the geographic detector method found that soil water storage, aspect and field capacity were the dominant factors affecting the PCSWDI of the shrubland; The interactive detection showed that the spatial differentiation of the PCSWDI of the 0-100 cm soil layer of shrubland was the result of the interaction of multiple factors. In conclusion, our results show that although there was no soil water deficit in the 0-100 cm soil layer of shrubland, a significant decrease in the 100-200 cm soil water content indicating the depletion of deep soil water was observed. Therefore, vegetation restoration in arid and semi-arid regions must take into account the carrying capacity and water threshold of vegetation, and a nature-based solution may be the main focus of vegetation restoration in the future.

Key words: desert steppe, anthropogenic shrub encroachment, soil water, geographic detector method, plot compared soil water deficit index