地理学报 ›› 2019, Vol. 74 ›› Issue (3): 520-533.doi: 10.11821/dlxb201903009

所属专题: 气候变化与地表过程

• 气候变化与地表过程 • 上一篇    下一篇

青藏高原地表土壤水变化、影响因子及未来预估

范科科1,2,3(), 张强1,2,3(), 孙鹏4, 宋长青1,2,3, 朱秀迪1,2,3, 余慧倩1,2,3, 申泽西1,2,3   

  1. 1. 北京师范大学环境演变与自然灾害教育部重点实验室,北京 100875
    2. 北京师范大学地表过程与资源生态国家重点实验室,北京 100875
    3. 北京师范大学地理科学学部,减灾与应急管理研究院,北京 100875
    4. 安徽师范大学地理与旅游学院,芜湖 241002
  • 收稿日期:2017-08-31 修回日期:2018-12-08 出版日期:2019-03-25 发布日期:2019-03-19
  • 作者简介:

    范科科(1995-), 男, 河南驻马店人, 博士研究生, 主要从事生态水文和遥感水文等方面的研究。E-mail: fankk95@hotmail.com

  • 基金资助:
    国家自然科学基金委创新群体项目(41621061);国家杰出青年科学基金项目(51425903);国家自然科学基金项目(41771536, 41601023)

Variation, causes and future estimation of surface soil moisture on the Tibetan Plateau

Keke FAN1,2,3(), Qiang ZHANG1,2,3(), Peng SUN4, Changqing SONG3, Xiudi ZHU1,2,3, Huiqian YU1,2,3, Zexi SHEN1,2,3   

  1. 1. Key Laboratory of Environmental Change and Natural Disaster, Ministry of Education, Beijing Normal University, Beijing 100875, China
    2. Academy of Disaster Reduction and Emergency Management, Beijing Normal University, Beijing 100875, China
    3. Faculty of Geographical Science, Beijing Normal University, Beijing 100875, China
    4. College of Geography and Tourism, Anhui Normal University, Wuhu 241002, Anhui, China
  • Received:2017-08-31 Revised:2018-12-08 Online:2019-03-25 Published:2019-03-19
  • Supported by:
    Creative Research Groups of National Natural Science Foundation of China, No.41621061;National Science Foundation for Distinguished Young Scholars of China, No.51425903;National Natural Science Foundation of China, No.41771536, No.41601023

摘要:

土壤水分是地表和大气连接的纽带,在水文循环中扮演着重要角色。青藏高原作为“第三极”和“亚洲水塔”,其土壤水分对周边地区的气候如亚洲季风的形成和维持产生重要影响,也深刻影响着亚洲水资源的可利用量。基于分布在青藏高原3个气候区的100个站点的实测土壤水数据,对ECV、ERA、MERRA、Noah数据集进行评价,选择对土壤水分评估效果最好的数据集,分析各种气象要素对土壤水分时空格局的影响,并预估未来100年内青藏高原土壤水变化,探讨可能气候成因。结果表明:① Noah数据集对青藏高原历史时期土壤水分评估效果最好,相对其他地区,各数据集对那曲地区土壤水分评估效果最优;② 在各种气象因子中,降水是影响大部分地区土壤水分时空变化的最主要因子,但在喜马拉雅山脉地带,尤其山脉北坡,温度和太阳辐射有较高的影响;③ 1948-1970年土壤水分有明显的下降趋势,1970-1990年土壤水分呈波动变化,无明显趋势,1990-2005年土壤水分有一定的上升趋势,2005年后至今土壤水分有明显快速下降趋势:④ 不同未来情景,土壤水分有下降趋势,其中在CRP 8.5情景下,土壤水分下降最为明显,在2080年之后有更加显著的下降趋势;⑤ 未来降水和温度均呈上升趋势,其中干旱指数变化在RCP 8.5情景下呈下降趋势,在RCP 2.6和RCP 4.5情景下无明显变化,干旱指数在一定程度上能解释未来土壤水分的变化格局。

关键词: 青藏高原, 土壤水, 干旱指数, 气候情景, 气候模式

Abstract:

Soil moisture is the link between the land surface and the atmosphere, which plays an important role in the hydrological cycle. As the "Third Pole" and "Asian Water Tower", the Tibetan Plateau has an important influence on the climate of the surrounding areas such as the formation and maintenance of the Asian monsoon and it also profoundly affects the availability of Asian water resources. Based on the measured soil moisture data from 100 stations distributed in the three climate zones on the Tibetan Plateau, this paper assesses the ECV, ERA, MERRA and Noah datasets, selects the best evaluated dataset for surface soil moisture, and analyzes the influence of various meteorological factors on spatial and temporal patterns of soil moisture changes. Finally, the paper evaluates the changes of surface soil moisture during the next about 100 years and explores possible climate causes. The results show that: (1) The Noah dataset has the best assessment of surface soil moisture in the Qinghai-Tibet Plateau during the historical period. Among all the regions, Naqu obtains the best assessment of surface soil moisture in each dataset. (2) Among various meteorological factors, precipitation is the most important factor affecting the temporal and spatial patterns of soil moisture in most areas, but the temperature and solar radiation have a relatively high impact in the Himalayas, especially on the north slope of the mountains. (3) The surface soil moisture had a significant downward trend from 1948 to 1970. However, it did not fluctuate obviously from 1970 to 1990. From 1990 to 2005, there existed a certain upward trend. Conversely, it has a rapid downward trend since 2005. (4) There is a downward trend for surface soil moisture in different future scenarios. Compared with the RCP2.6 and RCP4.5 scenarios, the soil moisture declines obviously with a more significant downward trend after 2080 under the RCP8.5 scenerio. (5) In the future, both precipitation and temperature show an upward trend. There was a downward trend for the drought index in the RCP8.5 scenario, whereas, there is no significant change under the RCP2.6 and RCP4.5 scenarios. The drought index can explain the change of surface soil moisture in the future to a certain extent.

Key words: Tibetan Plateau, soil moisture, drought index, climate scenario, GCM