Ecological balance is a dynamic balance. Once disturbed by natural and man-made factors, it exceeds the self-regulation ability of the ecosystem, and cannot be restored to its original stable state, the structure and function of the ecosystem are destroyed, and the input and output of matter and energy are unbalanced, resulting in system component defects (such as the reduction of biodiversity, etc.). ), structural changes (such as sudden increase or decrease of animal population, changes in food chain, etc. ), the energy flow is blocked and the material circulation is interrupted, which is generally called ecological imbalance and serious ecological disaster.