Eichhornia crassipes and Salvinia molesta are two of the world’s worst aquatic invasive alien plant Species (AIAPS) that have a major impact on the environment, agricultural production and food security. The aim of this study was to understand the current and potential distribution of E. crassipes and S. molesta under climate change in the tropical island of Sri Lanka. The MaxEnt species distribution modelling technique was used to generate predictive models using global distribution data and environmental variables. For future projections, the mean of two best performing climate models was used under two emissions scenarios, Representative Concentration Pathways (RCP) 4.5 and 8.5 for time periods 2050 and 2070. The study revealed that at present, the majority of the aquatic habitats of the country, particularly lowland areas, are vulnerable to the invasion of these two species; however, a striking difference was observed under future RCP scenarios. Aquatic habitats suitable for E. crassipes is predicted to decrease substantially by 2050 and increase again until 2070. The suitable habitats of S. molesta are likely to decrease sharply until 2070. This study provides insights for decision-makers that climate change influences should be considered for long-term management of AIAPS.

Eichhornia crassipes和Salvinia molesta是世界上最严重的两种水生外来入侵植物物种（AIAPS），对环境，农业生产和粮食安全产生重大影响。这项研究的目的是了解当前的和潜在的E. crassipes和S. molesta分布在热带岛屿斯里兰卡的气候变化下。MaxEnt物种分布建模技术用于使用全局分布数据和环境变量生成预测模型。对于未来的预测，在两种排放情景下使用了两种表现最佳的气候模型的平均值，即2050年和2070年的代表浓度路径（RCP）4.5和8.5。研究表明，目前，该区域的大多数水生生境国家，特别是低地地区，很容易受到这两种物种的入侵；但是，在未来的RCP方案下，观察到了显着差异。预计到2050年，适合于E. crassipes的水生生境将大量减少，直到2070年将再次增加。S. molesta的适宜生境 到2070年可能会急剧下降。本研究为决策者提供了见识，即对AIAPS的长期管理应考虑气候变化的影响。