X img

官方微信

img

群号:冰川冻土交流群

QQ群:218834310

高级检索
作者投稿 专家审稿 编辑办公 编委办公 主编办公

冰川冻土 ›› 2023, Vol. 45 ›› Issue (1): 54-66.doi: 10.7522/j.issn.1000-0240.2023.0003

• 第二次青藏高原综合科学考察研究 • 上一篇    下一篇

基于SHAW模型的青藏高原季节冻土区土壤温湿度模拟与评估

薛伟1(), 周毓彦1(), 刘建伟1,2, 鲁帆1, 侯保灯1, 胡莹莹1, 肖伟华1   

  1. 1.中国水利水电科学研究院 流域水循环模拟与调控国家重点实验室,北京 100038
    2.河海大学 水文水资源学院,江苏 南京 210098
  • 收稿日期:2022-05-04 修回日期:2022-08-23 出版日期:2023-02-28 发布日期:2023-02-25
  • 通讯作者: 周毓彦 E-mail:1751553454@qq.com;zhyy@iwhr.com
  • 作者简介:薛伟,硕士研究生,主要从事水文水资源研究. E-mail: 1751553454@qq.com
  • 基金资助:
    国家自然科学基金项目(51909275);第二次青藏高原综合科学考察研究项目(2019QZKK0207);中国水利水电科学研究院基本科研业务费专项(WR110145B0052021);流域水循环模拟与调控国家重点实验室开放研究基金项目(IWHR-SKL-KF202204);青海省中央引导地方科技发展资金项目(2022ZY020)

Simulation and assessment of soil temperature and moisture in seasonally frozen soil regions of the Tibetan Plateau based on SHAW model

Wei XUE1(), Yuyan ZHOU1(), Jianwei LIU1,2, Fan LU1, Baodeng HOU1, Yingying HU1, Weihua XIAO1   

  1. 1.State Key Laboratory of Simulation and Regulation of River Basin Water Cycle,China Institute of Water Resources and Hydropower Research,Beijing 100038,China
    2.College of Hydrology and Water Resources,Hohai University,Nanjing 210098,China
  • Received:2022-05-04 Revised:2022-08-23 Online:2023-02-28 Published:2023-02-25
  • Contact: Yuyan ZHOU E-mail:1751553454@qq.com;zhyy@iwhr.com

摘要:

不同气象条件对青藏高原土壤含水量与土壤温度具有重要影响,采用土壤水热耦合模型模拟青藏高原季节冻土区土壤水分、温度的变化特征是反映冻融作用下土壤水循环过程的重要手段。研究针对青藏高原不同气象条件下典型季节冻土区土壤温湿度特征差异性的关键问题,采用土壤水热耦合模型SHAW及三种土壤水分特征曲线模型对玛曲、那曲、狮泉河地区2017—2018年土壤温湿度变化特征进行模拟,分析不同气象条件下土壤温湿度模拟效果及变化特征,研究不同土壤水分特征曲线模型对模拟效果的影响。结果表明:SHAW模型能较好地模拟不同气象条件下土壤温湿度随时间的变化特征和垂向分布特征,土壤温度模拟效果好于土壤湿度,土壤温度的平均NSE、R2、RMSE分别为0.88、0.96和2.2 ℃,土壤湿度的平均NSE、R2、RMSE分别为0.60、0.72和0.03 m3·m-3;从不同气象条件来看,干旱区的土壤温度模拟效果显著优于湿润区,而湿润区的土壤水分模拟效果显著优于干旱区;从不同深度来看,土壤温度模拟效果随深度增加逐渐降低,而在半湿润区中下层土壤水分模拟效果好于表层;从不同水分特征曲线模型来看,采用不同土壤水分特征曲线模型对土壤温度模拟效果无显著影响,而在土壤水分模拟效果上存在显著差异性;此外,不同冻融阶段土壤温湿度模拟效果存在较大差异性和不确定性。研究结果可为揭示冻融条件下土壤温湿度变化规律提供参考。

关键词: 土壤温度, 土壤湿度, SHAW, 土壤水分特征曲线模型, 青藏高原

Abstract:

In recent years, more and more attention has been paid to the problem of the cryosphere changes on the Tibetan Plateau, and it has gradually become a hot issue for scholars. Known as the “water tower of Asia”, the Tibetan Plateau is the source of many major rivers in Asia. Under the combined influence of climate change and human activities, water resources on the Tibetan Plateau have undergone profound changes, especially soil water, as an important component of water resources, which plays an important role in regulating vegetation and crop growth, rainfall and runoff. However, global warming leads to the degradation of permafrost and seasonally frozen soil, which affects the original water cycle process and the spatial and temporal pattern of water resources by changing the properties of soil water storage and water transport. In the Tibetan Plateau, where there are few data, it is difficult to directly study the soil water cycle process under freezing-thawing by using original data. Therefore, it is an important means to simulate the variation characteristics of soil water and temperature under freezing-thawing in seasonally frozen soil regions of the Tibetan Plateau by using coupling model of soil water and heat. Aiming at the key problem of the difference of soil temperature and moisture characteristics in typical seasonally frozen soil regions under different meteorological conditions, this paper simulated the characteristics of soil moisture and temperature change in Maqu, Naqu (Nagqu) and Shiquanhe from 2017 to 2018 by using SHAW (Simultaneous Heat and Water) model and three soil moisture characteristic curve models. The simulation effect and variation characteristics of soil moisture and temperature under different meteorological conditions were analyzed, and the influence of soil moisture characteristic curve model on the simulation effect was studied. The results show that SHAW model can well simulate the temporal variation and vertical distribution of soil temperature and moisture under different meteorological conditions. The simulation effect of soil temperature is better than that of soil moisture. The average NSE, R2 and RMSE of soil temperature are 0.88, 0.96 and 2.20 ℃, respectively. The mean NSE, R2 and RMSE of soil moisture are 0.60, 0.72 and 0.03 m3·m-3, respectively. In terms of different meteorological conditions, the simulation effect of soil temperature in relatively dry region was significantly better than that in humid region, while the simulation effect of soil water in relatively humid region was significantly better than that in arid region. From different depths in soil, the simulation effect of soil temperature decreases gradually with the increase of depth, while the simulation effect of soil moisture in the middle and lower layers is better than that in the surface layer. From the view of different soil moisture characteristic curve models, different soil water characteristic curve models have no significant effect on soil temperature simulation effect, but there are significant differences in soil moisture simulation effect. In addition, there are great differences and uncertainties in simulating soil temperature and moisture in different freezing-thawing stages. With the increasing trend of climate warming, permafrost and seasonally frozen soil on the Tibetan Plateau may continue to degrade, may change the current water resources pattern, resulting in frequent extreme weather events. Therefore, from the perspective of numerical simulation, this paper verified the applicability of soil moisture and heat coupling model in soil temperature and moisture simulation under different meteorological conditions, revealed the influence of precipitation and temperature on soil temperature and moisture simulation at different depths in seasonally frozen soil regions, and analyzed the differences in simulation effects of different soil moisture characteristic curve models. The results provide reference for the study of soil water resources variation under freezing-thawing conditions.

Key words: soil temperature, soil moisture, SHAW, soil water characteristic curve model, Tibetan Plateau

中图分类号: 

  • S152