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Societal Impact StatementThe invasive speciesS. alternifloraandP. australisare fast growing coastal wetland plants sequestering large amounts of carbon in the soil and protect coastlines against erosion and storm surges. In this global analysis, we found thatSpartinaandPhragmitesincrease methane but not nitrous oxide emissions, withPhragmiteshaving a lesser effect. The impact of the invasive species on emissions differed greatly among different types of native plant groups, providing valuable information to managers and policymakers during coastal wetland planning and restoration efforts. Further, our estimated net emissions per wetland plant group facilitate regional and national blue carbon estimates. SummaryGlobally,Spartina alternifloraandPhragmites australisare among the most pervasive invasive plants in coastal wetland ecosystems. Both species sequester large amounts of atmospheric carbon dioxide (CO2) and biogenic carbon in soils but also support production and emission of methane (CH4). In this study, we investigated the magnitude of their net greenhouse gas (GHG) release from invaded and non‐invaded habitats.We conducted a meta‐analysis of GHG fluxes associated with these two species and related soil carbon content and plant biomass in invaded coastal wetlands.Our results show that both invasive species increase CH4fluxes compared to uninvaded coastal wetlands, but they do not significantly affect CO2and N2O fluxes. The magnitude of emissions fromSpartinaandPhragmitesdiffers among native habitats. GHG fluxes, soil carbon and plant biomass ofSpartina‐invaded habitats were highest compared to uninvaded mudflats and succulent forb‐dominated wetlands, while being lower compared to uninvaded mangroves (except for CH4).This meta‐analysis highlights the important role of individual plant traits as drivers of change by invasive species on plant‐mediated carbon cycles.
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Novel genome characteristics contribute to the invasiveness of Phragmites australis (common reed)
Abstract The rapid invasion of the non‐nativePhragmites australis(Poaceae, subfamily Arundinoideae) is a major threat to native wetland ecosystems in North America and elsewhere. We describe the first reference genome forP. australisand compare invasive (ssp.australis) and native (ssp.americanus) genotypes collected from replicated populations across the Laurentian Great Lakes to deduce genomic bases driving its invasive success. Here, we report novel genomic features including aPhragmiteslineage‐specific whole genome duplication, followed by gene loss and preferential retention of genes associated with transcription factors and regulatory functions in the remaining duplicates. Comparative transcriptomic analyses revealed that genes associated with biotic stress and defence responses were expressed at a higher basal level in invasive genotypes, but native genotypes showed a stronger induction of defence responses when challenged by a fungal endophyte. The reference genome and transcriptomes, combined with previous ecological and environmental data, add to our understanding of mechanisms leading to invasiveness and support the development of novel, genomics‐assisted management approaches for invasivePhragmites.
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- PAR ID:
- 10363942
- Publisher / Repository:
- Wiley-Blackwell
- Date Published:
- Journal Name:
- Molecular Ecology
- Volume:
- 31
- Issue:
- 4
- ISSN:
- 0962-1083
- Page Range / eLocation ID:
- p. 1142-1159
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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