College of Environmental Science and Engineering, Nankai University, Tianjin 300350, China.
Faculty of Geography, Tianjin Normal University, Tianjin 300387, China.
Sci Total Environ. 2024 Dec 1;954:176383. doi: 10.1016/j.scitotenv.2024.176383. Epub 2024 Sep 21.
Biological invasion poses a significant threat to biodiversity conservation and also results in substantial economic loss including the excessive cost of management to control it. Still, its impact on plant sexual reproduction strategies remains underexplored in natural settings. We conducted a field experiment on native Phragmites australis and invasive Spartina alterniflora in Bohai Bay and assessed plant size (aboveground biomass and height) and sexual reproduction (ear biomass, reproductive allocation, etc.) in conjunction with water and soil properties. The results showed that during the early stage of invasion, the two species declined in size and sexual reproduction, with S. alterniflora showing a lesser decline than P. australis. However, in the late stage of invasion, S. alterniflora maintained its plant size by reducing its investment in sexual reproduction. Moreover, significant reproductive allometries were demonstrated by S. alterniflora under different competition intensities. P. australis displayed heightened sensitivity to water properties and soil non-resource conditions, while S. alterniflora adapted its inherent traits and environmental tolerance. S. alterniflora allocated more resources to thriving as an individual, while P. australis prioritized reproduction by increasing seed production. Overall, this study revealed the reproductive strategies that invasive and native species employ in response to competition and environmental factors, thereby offering crucial insights for conservation and management efforts.
生物入侵对生物多样性保护构成重大威胁，同时也导致了巨大的经济损失，包括控制生物入侵所需的高额管理成本。然而，生物入侵对植物有性繁殖策略的影响在自然环境中仍未得到充分探索。我们在渤海湾对本地芦苇和入侵的互花米草进行了实地实验，结合土壤和水分特性评估了植物的大小（地上生物量和高度）和有性繁殖（耳生物量、生殖分配等）。结果表明，在入侵的早期阶段，这两个物种的大小和有性繁殖都有所下降，互花米草的下降幅度小于芦苇。然而，在入侵的后期阶段，互花米草通过减少有性繁殖的投入来维持其植物大小。此外，互花米草在不同的竞争强度下表现出显著的生殖异速性。芦苇对水分特性和土壤非资源条件更为敏感，而互花米草则适应了其内在特性和环境耐受性。互花米草将更多的资源分配给个体的生长，而芦苇则通过增加种子产量来优先繁殖。总的来说，本研究揭示了入侵和本地物种在应对竞争和环境因素时所采用的繁殖策略，为保护和管理工作提供了重要的见解。
