资源科学 ›› 2020, Vol. 42 ›› Issue (6): 1175-1187.doi: 10.18402/resci.2020.06.14

• 水资源 • 上一篇    下一篇

西北内陆区水量平衡要素时空分析

刘启航(), 黄昌()   

  1. 西北大学,陕西省地表系统与环境承载力重点实验室,西安 710127
  • 收稿日期:2019-09-17 修回日期:2019-12-26 出版日期:2020-06-25 发布日期:2020-08-25
  • 通讯作者: 黄昌
  • 作者简介:刘启航,男,陕西西安人,硕士研究生,研究方向为遥感和GIS应用。E-mail: tttngliuqi@qq.com
  • 基金资助:
    国家重点研发计划项目(2017YFC0404302);国家自然科学基金项目(41501460)

Spatiotemporal change of water balance components in the inland region of Northwest China, 1998-2017

LIU Qihang(), HUANG Chang()   

  1. Shaanxi Key Laboratory of Earth Surface System and Environmental Carrying Capacity, Northwest University, Xi’an 710127, China
  • Received:2019-09-17 Revised:2019-12-26 Online:2020-06-25 Published:2020-08-25
  • Contact: HUANG Chang

摘要:

近几十年来,气候变化和人类活动的加剧导致西北内陆区的水资源以及相关水量平衡要素的时空分布发生了显著的变化。本文借助Google Earth Engine(GEE)遥感云计算平台,基于该平台集成的多源遥感数据集,从西北内陆区全流域和三级流域两个空间尺度,对1998—2017年近20年西北内陆地区多个水量平衡要素的年际和年内变化进行时空分析,进而揭示区域总蓄变量、降水量、土壤湿度、蒸散发、地表水等核心水量平衡要素的空间分布特征与时间演变规律。研究结果表明:①在全流域尺度,研究区整体的升温趋势导致高海拔地区冰雪消融加剧、下游低海拔平原及盆地水分补给增加,使得总蓄变量呈现“高海拔减少低海拔增加”的趋势,同时,低海拔地区的地表水面积、土壤湿度和蒸散发亦相应地表现出一定的增加趋势;②在时间尺度上,各水量平衡要素除沙漠和荒漠地区外季节分异性明显,一般在夏秋达到最大,在春冬季时最小;③在三级流域尺度,不同的子流域由于水分补给来源的不同,各水量平衡要素具有不同的协同演变关系,以冰雪补给为主的流域,各要素呈现与总蓄变量相似的变化趋势,而以降水补给为主的流域,各要素变化与降水的波动关系更为密切。总之,西北内陆区各水量平衡要素在不同的时空尺度上呈现了明显的差异性,本文可为变化环境下进一步深入理解各要素协同演变特征提供重要参考。

关键词: 多源遥感数据, 水量平衡要素, 地表水, 水循环, 西北内陆区

Abstract:

In the recent decades, increased climate change and human activities have been affecting the spatial and temporal distribution of water resources and water balance components in the inland region of Northwest China. This study used a remote sensing cloud computing platform, Google Earth Engine (GEE), to explore the spatial and temporal dynamics of water balance components in this area at both basin and sub-basin scales with both interannual and intraannual analyses over the last two decades. Multi-source remote sensing datasets were employed to fulfill this purpose. The study tried to reveal the spatial distribution characteristics and temporal change of key water balance components, including terrestrial water storage, precipitation, soil moisture, evapotranspiration, and surface water. The results show that: (1) At the whole basin scale, due to the increasing trend of air temperature, glaciers and snow in high altitude areas were melting with an increasing speed, which provides more water supply to the low altitude basins. Therefore, the terrestrial water storage exhibit a pattern of “decreasing at high altitude and increasing at low altitude”. Meanwhile, surface water area, soil moisture and evapotranspiration also showed a certain increasing trend accordingly. (2) At temporal scale, except for the desert areas, different water balance components exhibited different seasonal variations. The value of each component generally reaches the maximum in the summer and the autumn, and becomes the lowest in the spring and the winter. (3) At sub-basin scale, due to the different combinations of water sources, the variation patterns between different water balance components differ from sub-basin to sub-basin. In the ice and snow water dominated sub-basins, each component showed a similar variation pattern as the terrestrial water storage, while in the precipitation dominated sub-basins, the variation of each component is more closely related to precipitation fluctuation. In conclusion, different water balance components exhibit different characteristics at different spatial and temporal scales in the inland area. This study provides valuable reference for further understanding the co-evolution pattern of these components.

Key words: multi-source remote sensing data, water balance components, surface water, water cycle, northwest inland area