ABSTRACT

Flow regime is a key driver of invasive aquatic organisms, and the invasiveness of mangrove species may be simultaneously attributed to plant traits and flowing hydrological conditions at the estuary scale. We focused on hydrological and topographic conditions for a non-native mangrove species, Sonneratia apetala, in Zhangjiang Estuary of Fujian, China. A hydrological model and a micro-topographic model were used to predict its dispersal and early establishment, and field surveys and simulated experiments were integrated to estimate its future dispersal patterns. The mesohaline mudflat with a salinity of 8 ~ 10 PSU at the mangrove seaward edge was the most likely colonization area for S. apetala under current conditions. The south-western region of the estuary with native mangroves was the most likely area for its colonization according to the unstructured-grid finite-volume community ocean model (FVCOM) in September, when the largest tidal currents within a year and the maximum fruit maturity period occur. Approximately 42% of the mudflats throughout the whole estuary may be available for seedling establishment under the future sea-level rise RCP 4.5 scenarios compared with 44% for current establishment; however, the RCP 8.5 scenarios would significantly decrease seedling establishment by 2100 due to serious tidal inundation according to the micro-topographical model.

摘要

流动状态是入侵性水生生物的关键驱动力，红树林物种的入侵性可能同时归因于河口规模的植物性状和流动的水文条件。我们重点研究了福建张江河口非本土红树林物种Sonneratia apetala的水文和地形条件。使用水文模型和微地形模型来预测其扩散和早期建立，并结合现场调查和模拟实验来评估其未来的扩散模式。在红树林的海缘，盐度为8〜10 PSU的中卤代泥滩是拟南芥最可能的定居区。在当前条件下。根据9月的非结构化网格有限体积群落海洋模型（FVCOM），河口西南部具有原生红树林的区域是最有可能被定殖的地区，当时潮汐流一年内最大，果实成熟度最高期间发生。在未来海平面上升RCP 4.5情景下，整个河口约有42％的滩涂可用于苗木建立，而目前的泥滩为44％；然而，根据微观地形模型，RCP 8.5方案将由于严重的潮汐淹没而在2100年之前显着减少幼苗的形成。