Effect of human activity intensity on stream structure and connectivity in Shaying River Basin, China

In order to quantify the relationship between human activity intensity and the evolution of stream structure and connectivity, the characteristics of spatial distribution and temporal evolution of stream structure and connectivity in different periods were studied by using river structure parameters and landscape ecology methods. The results indicate the following. (1) The mainstream trend of stream system, with the stream development coefficient decreased by 18.35% and 22.50% for the second- and third-level of stream, is obvious. (2) Human activity intensity has a significant impact on the change of stream structure and connectivity. Under the background of economy domination, the stronger human intervention is, the simpler stream structure will be, and the poorer stream connectivity will be. (3) From the view of time series, it is considered that human activities are the main reasons for affecting the change of stream structure and connectivity in the short term, while the natural factors have little effect. (4) The length of low-level streams is more affected by human activities than that of the high-level streams, but water surface ratio is opposite. This study can provide a reference for coordinating the contradiction between socio-economic development and protection of stream systems.