Chin J Plant Ecol ›› 2025, Vol. 49 ›› Issue (6): 922-938.DOI: 10.17521/cjpe.2024.0160  cstr: 32100.14.cjpe.2024.0160

• Research Articles • Previous Articles     Next Articles

Spatiotemporal evolution and landscape pattern analysis of the invasive species Spartina alterniflora in the Yellow River Delta wetland

DUAN Jun-Cheng, WANG Zhi-Yong*(), GAO Wei-Cong, ZHANG Cheng-Kai, GAO Chang-Hong, LIU Xiao-Tong, LI Zhen-Jin   

  1. College of Geodesy and Geomatics, Shandong University of Science and Technology, Qingdao, Shandong 266590, China
  • Received:2024-05-16 Accepted:2024-09-28 Online:2025-06-20 Published:2024-09-29
  • Contact: WANG Zhi-Yong
  • Supported by:
    Supported by the National Natural Science Foundation of China(41876202);National Undergraduate Innovation and Entrepreneurship Training(202111031101)

Abstract:

Aims In recent years, the invasion of Spartina alterniflora has caused significant damage to the structure and function of the wetland ecosystem in the Yellow River Delta Nature Reserve. Analyzing the invasion characteristics and landscape pattern changes of S. alterniflora over a long-term period holds considerable ecological importance.

Methods In this study, we use long-term Landsat optical remote sensing images as the primary data source, focusing on the wetlands of the Yellow River. Employing a support vector machine classification algorithm, we extracted wetland type information of the Yellow River Delta from 2000 to 2022. This allowed us to uncover the spatiotemporal dynamics of the wetlands. Additionally, we applied eight landscape pattern indices to examine the outbreak characteristics of S. alterniflora and conducted further analysis on its spatial pattern, evolution characteristics, and associated ecological factors.

Important findings The results revealed that: (1) The average overall accuracy of ground object extraction across 23 periods was 88.60%, with an average Kappa coefficient of 0.85. The Support Vector Machine algorithm demonstrated higher classification accuracy compared to other traditional machine learning methods, making it highly effective for analyzing wetland evolution mechanisms. (2) The long-term wetland evolution analysis showed distinct phases in the expansion of S. alterniflora. From 2002 to 2010, its expansion was slow. However, since 2010, the expansion on both sides of the Yellow River estuary entered an explosive phase. By 2012, its area had increased to 22.63 km2, continuing to grow steadily, reaching 50.42 km2 by 2021. The landscape pattern index indicated that S. alterniflora has a significant ecological advantage in the study area. Fragmented patches of S. alterniflora have progressively merged and connected, invading native wetland vegetation and creating a mosaic-like spatial pattern with other vegetation communities. (3) The expansion of S. alterniflora in the study area showed a high correlation with hydrothermal conditions, sunshine duration, topography, and the mudflat environment. Among these factors, the correlation between sunshine conditions, proximity to the sea, and the growth of S. alterniflora was particularly strong. These findings provide theoretical support for relevant departments in the sustainable management and utilization of wetlands in the Yellow River Delta Nature Reserve, as well as in the control and eradication of S. alterniflora.

Key words: Spartina alterniflora, long-term remote sensing monitoring, Yellow River Delta, wetland classification, evolution mechanism analysis