Ecosystem service relationships: Formation and recommended approaches from a systematic review

Ecosystem services interact and can form neural, synergic, and trade-off relationships with each other. Current studies of ecosystem service relationships have focused more on quantification without analyzing the driver of these interactions. Here, we proposed a qualitative method based on the number of shared optimal ecosystem attributes among services to study the possible driver of ecosystem service relationships and applied it to five ecosystem services (erosion control, water yield, air quality regulation, cooling effect, and carbon sequestration) as examples. The optimal approach of three categories of ecosystem attributes, namely spatial configuration, shape and size, and structure, for these five ecosystem services was summarized by systematically reviewing 116 related studies. Results suggested that synergic relationships were more likely to occur among erosion control, air quality regulation, and cooling effect since they had high numbers of shared optimal ecosystem attributes. A high possibility of trade-off relationships was found between carbon sequestration, cooling effect, and air quality regulation due to the relatively high number of contrary optimal ecosystem attributes they shared. Validation from previous studies supported these findings. The optimal attributes from this method might also provide general guidance for designing landscapes that aim to provide additional, diverse ecosystem services.