期刊名称：Proceedings of the National Academy of Sciences
印刷版ISSN：0027-8424
电子版ISSN：1091-6490
出版年度：2022
卷号：119
期号：28
DOI：10.1073/pnas.2123274119
语种：English
出版社：The National Academy of Sciences of the United States of America
摘要：Significance
“Red Beach” ecosystems along the Yellow Sea coastline are biodiversity hotspots critical for migratory shorebirds of the East Asian–Australasian Flyway. Satellite images show that these ecosystems have been shrinking markedly in recent decades. The reasons for this loss are unknown. Here, we reveal a landscape-scale biotic interaction driven by the destructive effect of invasive cordgrass on native coastal saltmarsh ecosystems that has progressively emerged over the past four decades. In contrast to previous studies showing positive effects of long-distance interactions, our study demonstrates that this negative interaction operating over 10 km is leading to the extinction of the “Red Beach” ecosystem and will dramatically impact ecosystem resilience to sea-level rise in the coming decades.
Biotic interactions that hierarchically organize ecosystems by driving ecological and evolutionary processes across spatial scales are ubiquitous in our biosphere. Biotic interactions have been extensively studied at local and global scales, but how long-distance, cross-ecosystem interactions at intermediate landscape scales influence the structure, function, and resilience of ecological systems remains poorly understood. We used remote sensing, modeling, and field data to test the hypothesis that the long-distance impact of an invasive species dramatically affects one of the largest tidal flat ecosystems in East Asia. We found that the invasion of exotic cordgrass
Spartina alterniflora can produce long-distance effects on native species up to 10 km away, driving decadal coastal ecosystem transitions. The invasive cordgrass at low elevations facilitated the expansion of the native reed
Phragmites australis at high elevations, leading to the massive loss and reduced resilience of the iconic
Suaeda salsa “Red Beach” marshes at intermediate elevations, largely as a consequence of reduced soil salinity across the landscape. Our results illustrate the complex role that long-distance interactions can play in shaping landscape structure and ecosystem resilience and in bridging the gap between local and global biotic interactions.
