3.1 AHP model
Based on the composition of the water system, we constructed an index system including boundary, flow and sediment (Fig. 2a, Table 1), which can reflect the fluidity and stability of the boundary, the fluidity and continuity of water flow, the transport and exchange of sediment, etc. The matching index of sediment can reflect the channel evolution. The matching index of minimum flow can reflect whether the incoming flow meets the ecological flow. The matching index of maximum flow can reflect whether the flood is a floodplain, which can also reflect the lateral connectivity.
Figure 2 Index system of the AHP; (a) Index System of Water System Connectivity; (b) Weight obtained by the AHP for channel connectivity