干旱区研究 ›› 2023, Vol. 40 ›› Issue (12): 1969-1981.doi: 10.13866/j.azr.2023.12.10

• 植物生态 • 上一篇    下一篇

西北干旱半干旱区NDVI季节性变化及其影响因素

吴万民1(),刘涛2(),陈鑫2   

  1. 1.成都信息工程大学资源与环境学院,四川 成都 610225
    2.清华大学全球变化研究中心地球系统科学系,地球系统模拟教育部重点实验室,北京 100084
  • 收稿日期:2023-05-24 修回日期:2023-08-25 出版日期:2023-12-15 发布日期:2023-12-18
  • 通讯作者: 刘涛. E-mail: liut22@mails.tsinghua.edu.cn
  • 作者简介:吴万民(2002-),男,主要从事遥感植被监测研究. E-mail: 17208281794@163.com
  • 基金资助:
    国家自然科学基金青年科学基金(42201279);中国博士后科学基金(2022M711755)

Seasonal changes of NDVI in the arid and semi-arid regions of Northwest China and its influencing factors

WU Wanmin1(),LIU Tao2(),CHEN Xin2   

  1. 1. School of Resources and Environment, Chengdu University of Information Technology, Chengdu 610225, Sichuan, China
    2. Department of Earth System Science, Center for Global Change Research, Tsinghua University, Key Laboratory of Earth System Simulation, Ministry of Education, Beijing 100084, China
  • Received:2023-05-24 Revised:2023-08-25 Online:2023-12-15 Published:2023-12-18

摘要:

研究植被的动态变化及其影响因素,不仅能够揭示植被覆盖动态变化特征与气候变化之间的响应机制,同时对区域的植被恢复以及生态可持续具有重要意义。本文基于MODIS遥感卫星数据,借助变异系数、趋势分析、相关分析与Hurst指数探究了2000—2020年西北干旱半干旱区植被覆盖逐季变化特征、影响因素及未来趋势。结果表明:(1) 归一化植被指数(Normalized Difference Vegetation Index, NDVI)空间变异程度在冬季偏高,且高波动主要分布在新疆与内蒙古大兴安岭的草地与未利用地区域。(2) NDVI随季节波动较大,在林地与耕地最为明显。(3) NDVI主要为改善趋势,其中,春季改善面积最大(84.63%),冬季最小(72.52%),且林地改善最为显著。(4) 各季度NDVI均受地表温度与降水量影响(Significance=0.05),且夏季地表温度与冬季降水量逐年递增对植被生长具有抑制作用。(5) 未来NDVI主要呈改善趋势。值得注意的是,退化区域零星分布于新疆塔里木盆地、准噶尔盆地等地区。本研究旨在为西北干旱半干旱区的生态修复与治理,以及局部气候暖湿化的应对提供理论参考。

关键词: NDVI, 植被变化趋势, 影响因素, MODIS, 未来预测, 干旱半干旱区, 西北

Abstract:

The study of vegetation dynamics and its influencing factors can reveal the response mechanism between vegetation cover dynamics and climate change and has important significance for regional vegetation restoration and ecological sustainability. Based on MODIS multitemporal remote sensing satellite data, this study investigated the quarterly changes in vegetation cover in the arid and semi-arid regions of Northwest China from 2000-2020 using variation coefficient, Theil-Sen median trend analysis, Mann-Kendall significance test, correlation analysis, and Hurst index. The study found that: (1) The spatial variability of the Normalized Difference Vegetation Index (NDVI) was high in winters, and the high fluctuation areas were mainly in the grasslands and unused land areas in the Daxinganling region of Xinjiang and Inner Mongolia. (2) NDVI fluctuates more with the seasons and is most obvious in forests and cultivated areas. (3) NDVI is mainly improving, with the largest improvement in springs (84.63%), the smallest in winters (72.52%), and the most significant improvement in the woodland areas. (4) Surface temperature and precipitation influenced NDVI in all seasons (Significance = 0.05), with precipitation changes significantly affecting NDVI trends in summers and weakly during winters and surface temperature changes significantly affecting NDVI trends in springs and weakly in autumns. (5) The future NDVI also mainly shows an improving trend, with an area of 70.89%; notably, the degraded areas are sporadically distributed in the Tarim and Junggar Basins of Xinjiang. This study’s results provide theoretical references for ecological restoration and management in the arid and semi-arid regions of Northwest China and the response to local climate warming and humidification.

Key words: NDVI, trends in vegetation cover, influencing factors, MODIS, future projections, arid and semi-arid region, Northwest China