The degree to which the distribution of mangrove forests will be impacted by climate change depends on the dispersal and establishment of sea-faring propagules, which drive forest rejuvenation, gene flow and range expansion. Climate change affects sea surface density via changes in temperature and salinity. However, these changes have not been mapped and it remains unclear how these factors may impact mangrove propagule dispersal. Here, we provide evidence for strong warming of coastal mangrove waters and elevated geographic variability in surface ocean density under representative concentration pathway RCP 8.5 by 2100. The largest changes will occur in the Indo West Pacific region, the primary hotspot of mangrove diversity. By comparing propagule densities to predicted sea surface density, we assessed potential effects on mangrove propagule dispersal. In the future, a warmer and fresher ocean is likely to alter dispersal trajectories of mangrove propagules and increase rates of sinking in unsuitable offshore locations, potentially reducing the resilience of mangrove forests.

气候变化对红树林分布的影响程度取决于海洋繁殖体的扩散和建立，这些繁殖体推动了森林的复兴、基因流动和范围的扩大。气候变化通过温度和盐度的变化影响海面密度。然而，这些变化尚未被绘制出来，目前尚不清楚这些因素如何影响红树林繁殖体的传播。在这里，我们提供证据表明，到 2100 年，在代表性浓度路径 RCP 8.5 下，沿海红树林水域的强烈变暖和地表海洋密度的地理变异性升高。最大的变化将发生在印度西太平洋地区，这是红树林多样性的主要热点。通过将繁殖体密度与预测的海面密度进行比较，我们评估了对红树林繁殖体传播的潜在影响。未来，更温暖、更新鲜的海洋可能会改变红树林繁殖体的扩散轨迹，并增加在不合适的近海位置下沉的速度，从而可能降低红树林的恢复力。