干旱区研究 ›› 2024, Vol. 41 ›› Issue (2): 191-199.doi: 10.13866/j.azr.2024.02.02 cstr: 32277.14.j.azr.2024.02.02

• 天气与气候 • 上一篇    下一篇

基于CWSI的汾河流域干旱时空变化特征

周义(), 索文姣()   

  1. 山西师范大学地理科学学院,山西 太原 030000
  • 收稿日期:2023-04-07 修回日期:2023-10-25 出版日期:2024-02-15 发布日期:2024-03-11
  • 作者简介:周义(1985-),男,博士,讲师,研究方向为资源环境遥感. E-mail: aboatnju@163.com
  • 基金资助:
    国家自然科学基金项目(41901339)

Spatialtemporal variation characteristics of drought in the Fenhe River Basin based on CWSI

ZHOU Yi(), SUO Wenjiao()   

  1. College of Geographical Sciences, Shanxi Normal University, Taiyuan 030000, Shanxi, China
  • Received:2023-04-07 Revised:2023-10-25 Published:2024-02-15 Online:2024-03-11

摘要:

基于MOD16数据,计算作物缺水指数(Crop Water Stress Index, CWSI),结合汾河流域气象站点数据、植被指数数据和土地利用数据,采用差值法、线性趋势法和相关分析法,分析汾河流域2000—2021年干旱时空变化特征。结果表明:(1)CWSI能有效监测汾河流域旱情,其与10 cm土壤相对湿度呈显著负相关。(2)汾河流域CWSI空间分布差异明显,呈现出南湿北旱的特点。(3)汾河流域CWSI年际变化较为平稳,而月变化波动较大,5月CWSI达到年内峰值。(4)汾河流域不同生长期内干旱情况差异显著,生长季前期(4—5月)特旱区占汾河流域总面积的48.55%;生长季中期(6—8月)基本全域无旱;生长季后期(9—10月),仅11.17%的地区发生干旱。(5)不同土地利用类型干旱程度不同,CWSI从小到大依次为:林地(0.686)<草地(0.749)<耕地(0.751)<未利用地(0.758)<城镇(0.765)。本研究结果可为汾河流域旱情监测和抗旱决策的制定提供科学数据支撑。

关键词: 干旱, 作物缺水指数(CWSI), 时空变化, 汾河流域

Abstract:

Based on MOD16 global evapotranspiration data, the Crop Water Stress Index (CWSI) was computed. This was combined with the meteorological station precipitation, temperature, and vegetation index data in the Fenhe River Basin, along with land use data. Employing the difference method, linear trend method, and correlation analysis, the temporal and spatial characteristics of drought in the Fenhe River Basin from 2000 to 2021 were analyzed. The results showed that: (1) CWSI effectively monitored drought in the Fenhe River Basin, displaying a notably negative correlation between CWSI and 10 cm soil relative moisture. (2) The spatial distribution of CWSI in the Fenhe River Basin exhibited significant disparities, illustrating wet conditions in the south and dry conditions in the north. (3) While interannual CWSI variations in the Fenhe River Basin remained relatively stable, monthly fluctuations were substantial, peaking in May annually. (4) Drought conditions varied distinctly during different growing periods in the Fenhe River Basin: significant drought occurred in the early growing season (April to May), encompassing 48.55% of the Fenhe River Basin area. No drought occurred in the mid-growing season (June to August). By the end of the growing season (September to October), only 11.17% of the area experienced drought. (5) Drought occurrences differed among various land use types, ranked by CWSI from smallest to largest: forest land (0.686) < grassland (0.749) < cultivated land (0.751) < unused land (0.758) < urban land (0.765). These study outcomes offer critical scientific data support for drought monitoring and decision-making regarding drought resistance in the Fenhe River Basin.

Key words: drought, Crop Water Stress Index, spatiotemporal changes, Fenhe River Basin