Coastal, freshwater wetlands in northern Australia are at risk of increased saltwater intrusion associated with sea-level rise, which threatens the persistence of numerous freshwater plant species by increasing salinity. Waterlilies (Nymphaea) are widespread in northern Australia, and their loss from these wetlands will be detrimental, both ecologically and culturally. This study aimed to define the regeneration tolerance of Nymphaea to increased salinity through quantifying the effects of salinity on seed germination and early seedling growth in four Nymphaea species. Seed germination and seedling growth were assessed under a gradient of salinity concentrations. Seeds that did not germinate after salinity exposure were assessed for their ability to recover in fresh water. For all species, there was a significant reduction in germination when seeds were exposed to salinities of ≥100 mM NaCl. Total seedling biomass was less sensitive to increasing salinity than germination, however declined significantly across all species at salinities ≥100 mM NaCl. Ungerminated seeds from all salinity treatments displayed some degree of recovery when transferred to fresh water. For the majority of species, however, seed germination of these transferred seeds never reached the percentages observed in the non-saline controls. For most species of Nymphaea, any salinization event reaching ≥100 mM NaCl will significantly reduce recruitment from seeds, irrespective of whether saline water is flushed from the system. The predicted future increases of saltwater intrusion into coastal freshwater wetlands in Northern Australia associated with global sea-level rise will likely result in significant habitat loss for many Nymphaea species.

澳大利亚北部沿海淡水湿地面临着与海平面上升相关的盐水入侵增加的风险，这通过增加盐度来威胁许多淡水植物物种的持久性。睡莲（Nymphaea）在澳大利亚北部广泛分布，它们从这些湿地中流失的情况在生态和文化上都是有害的。这项研究旨在通过定量盐度对四个睡莲种子萌发和幼苗早期生长的影响来定义睡莲对增加盐分的耐受性。种类。在盐度浓度梯度下评估种子发芽和幼苗生长。评估盐分暴露后未发芽的种子在淡水中恢复的能力。对于所有物种，当种子暴露于盐度≥100 mM NaCl时，发芽量均显着降低。盐分≥100 mM NaCl时，幼苗总生物量对盐度增加的敏感性低于发芽，但在所有物种中均显着下降。所有盐分处理的未发芽种子转移到淡水中均显示出一定程度的恢复。但是，对于大多数物种而言，这些转移种子的种子发芽从未达到在非盐类对照中观察到的百分比。对于大多数睡莲，任何盐化事件达到或超过100 mM NaCl都会显着减少种子的募集，而与是否从系统中冲洗掉盐水无关。随着全球海平面上升，预计到未来澳大利亚北部海域沿海淡水湿地的盐水入侵量将增加，这可能会导致许多睡莲物种的栖息地大量丧失。