Sea level rise threatens coastal peatlands globally, as increased salinity can cause peat collapse and formation of brackish ponds, replacing marshes. Sawgrass, Cladium jamaicense Crantz (Cyperaceae), is the charismatic macrophyte that dominates Everglades marshes (Florida, USA). Sawgrass root growth is reduced by salinity pulses of 20 ppt, impacting soil structure and organic input into coastal peats and possibly leading to coastal marsh loss. The potential for regeneration of coastal sawgrass marsh from seeds depends on how salinity affects sawgrass germination. Although adult sawgrass plants can tolerate salinities of 10–20 ppt in the field, the effect of salinity on seed germination is not known. In this study, sawgrass seeds were exposed to salinities of 0, 5, 15, and 25 ppt and observed weekly for germination over seven months (Oct. 2017-Apr. 2018). Twenty-eight percent of seeds in 0 ppt water germinated, while only 4% of seeds in 5 ppt germinated. Seeds in 15 and 25 ppt salt did not germinate. After 3.6 months, four-fifths of the seedling trays at the two higher salinities were transferred to 0 ppt. Beginning 7 weeks after transfer, 6% (15 ppt) and 3% (25 ppt) of transferred seeds germinated, while seeds remaining at the higher salinities did not. These results indicate that sawgrass seeds have greatly reduced or no germination in elevated salinity. If salinities rise in coastal areas, this lack of germination could prevent coastal sawgrass regeneration from seed, negatively affecting coastlines as sea level continues to rise.

海平面上升威胁全球泥炭地，因为盐分增加会导致泥炭倒塌和淡淡的池塘形成，从而取代沼泽。锯齿草，一本芒属jamaicenseCrantz（莎草科）是一种有魅力的大型植物，在大沼泽地（美国佛罗里达州）占主导地位。20 ppt的盐度脉冲会降低锯齿草根的生长，影响土壤结构和向沿海泥炭的有机输入，并可能导致沿海沼泽地流失。从种子再生沿海锯齿草沼泽的潜力取决于盐度如何影响锯齿草发芽。尽管成年的锯齿草植物在田间可以忍受10–20 ppt的盐度，但盐度对种子发芽的影响尚不清楚。在这项研究中，锯齿草种子暴露于0、5、15和25 ppt的盐度下，并在七个月内每周观察发芽情况（2017年10月至2018年4月）。0 ppt水中的28％种子发芽，而5 ppt中只有4％的种子发芽。含15和25 ppt盐的种子不发芽。3.6个月后，将两个较高盐度的育苗盘的五分之四转移到0 ppt。转移后7周开始，转移的种子中有6％（15 ppt）和3％（25 ppt）的种子发芽，而保持较高盐度的种子则没有发芽。这些结果表明，锯齿草种子在盐度升高的情况下发芽率大大降低或没有发芽。如果沿海地区的盐分上升，则这种发芽不足将阻止沿海锯齿草从种子中再生，随着海平面继续上升，对海岸线产生不利影响。这些结果表明，锯齿草种子在盐度升高的情况下发芽率大大降低或没有发芽。如果沿海地区的盐分上升，则这种发芽不足可能会阻止沿海锯齿草从种子中再生，随着海平面继续上升，对海岸线产生不利影响。这些结果表明，锯齿草种子在盐度升高的情况下发芽率大大降低或没有发芽。如果沿海地区的盐分上升，则这种发芽不足将阻止沿海锯齿草从种子中再生，随着海平面继续上升，对海岸线产生不利影响。