Chin J Plant Ecol ›› 2022, Vol. 46 ›› Issue (2): 148-161.DOI: 10.17521/cjpe.2021.0033

Special Issue: 生态遥感及应用

• Research Articles • Previous Articles     Next Articles

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)


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