Hydrological connectivity and herbivores control the autochthonous producers of coastal salt marshes

Yin, Shuo; Bai, Junhong; Wang, Xin; Wang, Xinyan; Zhang, Guangliang; Jia, Jia; Li, Xiaowen; Liu, Xinhui

Hydrological connectivity and herbivores control the autochthonous producers of coastal salt marshes

2020

Sea-level rise and overfishing could enhance the strength of hydrological connectivity and the presence of herbivores, resulting in salt marsh loss through physical stress and trophic cascade effects. Our aim was to estimate the effects of these two stresses on autochthonous producers. Survivorship and biomass of Suaeda salsa (S. salsa) were the lowest in areas with high hydrological connectivity, whereas the highest biomass was observed in the areas with moderate connectivity. The biomass of benthic microalgae was higher under low hydrological connectivity and no herbivores. The interactive effects between hydrological connectivity and herbivores on S. salsa but not on benthic microalgae were observed. Herbivores were somewhat (28%) important for the survival of initial S. salsa seedlings, while hydrological connectivity controlled (50%) the biomass of benthic microalgae. Our study highlights that, the autochthonous producers in coastal salt marshes may disappear due to strong hydrological connectivity and the excessive presence of herbivores.

Показать больше [+]