Journal d'écosystème et d'écographie

Abstrait

Phytoplankton Abundance Constrains Planktonic Energy Subsidy to Benthic Food Web

Peiyu Zhang1, Huijuan Tang, Zhijun Gong, Ping Xie and Jun Xu

Linkages across habitats between habitats are fundamental components of ecological processes. As a major characteristic of within-lake food webs, linkage of benthic and planktonic food webs has received a great deal of attention in recent aquatic studies. However, planktonic energy subsidy to benthic consumers has been infrequently tested in experiment. In a field experiment manipulating nutrients and phytoplankton abundance, we ask how changes in phytoplankton abundance affect planktonic energy subsidy to benthic primary consumers across nutrient levels. Our results suggest that the planktonic subsidy to benthic primary consumers depends on the phytoplankton abundance. Furthermore, highly taxon-specific planktonic energy subsidy to benthic primary consumers suggests that the benthic community composition partially determines the degree of the planktonic-benthic linkage. Because shallow and eutrophic lakes distribute worldwide, and many ecological functions are mediated by planktonic-benthic linkage, it will be important to consider these findings to protection and restoration of lake ecosystems.