植物生态学报 ›› 2022, Vol. 46 ›› Issue (2): 148-161.DOI: 10.17521/cjpe.2021.0033

所属专题: 遥感生态学

• 研究论文 • 上一篇    下一篇

水淹频率变化对鄱阳湖增强型植被指数的影响

文可1, 姚焕玫1,*(), 龚祝清1, 纳泽林1, 韦毅明1, 黄以1, 陈华权1, 廖鹏任1, 唐丽萍2   

  1. 1广西大学资源环境与材料学院, 南宁 530004
    2广西大学化学化工学院, 南宁 530004
  • 收稿日期:2021-01-25 接受日期:2021-07-15 出版日期:2022-02-20 发布日期:2021-08-06
  • 通讯作者: 姚焕玫
  • 作者简介:(191723450@qq.com)
    ORCID:文可: 0000-0002-1982-171X
  • 基金资助:
    广西研究生教育创新计划资助项目(YCSW2021038)

Influence of inundation frequency change on enhanced vegetation index of wetland vegetation in Poyang Lake, China

WEN Ke1, YAO Huan-Mei1,*(), GONG Zhu-Qing1, NA Ze-Lin1, WEI Yi-Ming1, HUANG Yi1, CHEN Hua-Quan1, LIAO Peng-Ren1, TANG Li-Ping2   

  1. 1School of Resources, Environment and Materials, Guangxi University, Nanning 530004, China
    2School of Chemistry and Chemical Engineering, Guangxi University, Nanning 530004, China
  • Received:2021-01-25 Accepted:2021-07-15 Online:2022-02-20 Published:2021-08-06
  • Contact: YAO Huan-Mei
  • Supported by:
    Innovation Project of Guangxi Graduate Education(YCSW2021038)

摘要:

水淹状况是湿地植被动态的重要影响因素。该研究基于谷歌地球引擎(GEE)平台, 利用2000-03-01至2020-02-29所有覆盖研究区域的MODIS遥感影像数据, 分析20年间水淹频率(IF)、增强型植被指数(EVI)的时空变化以及湿地植被对IF变化的响应, 得出以下结论: (1) 20年来鄱阳湖水文节律发生了明显改变, 高IF (IF > 75%)水域面积呈现下降趋势, 从2000年1 435.3 km2下降至2019年的510.25 km2, 降幅为64.45%; (2)区域平均EVI呈显著上升趋势, 植被扩张主要集中在中部IF下降区域; (3)分析不同总水淹频率区域中平均EVI年际变化, 发现EVI与水淹状况的变化趋势相似, 2009年之后鄱阳湖水域面积萎缩趋势缓解, EVI增长速度出现下降; (4)鄱阳湖湿地植被主要沿水域面积萎缩方向扩张, 基于像元统计20年间IFEVI的变化趋势, 发现它们在空间分布上高度吻合, 这种空间异质性进一步证实水淹状况起到调节植被动态变化的作用。

关键词: 水淹频率, 鄱阳湖, 湿地植被, MODIS, 增强型植被指数

Abstract:

Aims Inundation frequency (IF) is an important influencing factor on dynamics of wetland vegetation. This study analyzed the temporal and spatial variations of IF and enhanced vegetation index (EVI) of wetland vegetation and their correlation in Poyang Lake, so as to maintain the stability of wetland ecosystem.

Methods In view of the significant seasonal changes of Poyang Lake, its impact on wetland vegetation needs to be analyzed with a high temporal resolution method. Based on MODIS image data from 2000-03-01 to 2020-02-29, this study mapped the annual water inundation frequency of Poyang Lake, analyzed the temporal and spatial variations of EVI under different flooding conditions, and explored the response of EVI of wetland vegetation to changes in flooding conditions.

Important findings The following conclusions are drawn: (1) The hydrological rhythm of Poyang Lake has changed significantly in the past 20 years. The water area with high inundation frequency (IF >75%) decreased from 1 435.3 km2 in 2000 to 510.25 km2 in 2019, with a decrement of 64.45%. (2) The regional average EVI showed a significant upward trend. Vegetation expansion was mainly concentrated in the middle region of Poyang Lake which was also the main region of IF declining. (3) By analyzing the changes of average EVI value under different total IF regions, it was found that the variation trend of IF was similar to that of EVI. After 2009, the shrinking trend of the Poyang Lake water area was alleviated, and the growth rate of EVI decreased. (4) In the past 20 years, the changing trend of IF and EVI in Poyang Lake was highly consistent in spatial distribution. Wetland vegetation was mainly expanded along the decreasing direction of water area. This spatial heterogeneity further confirms that hydrological variation plays a role in regulating vegetation dynamics.

Key words: inundation frequency, Poyang Lake, wetland vegetation, MODIS, enhanced vegetation index