Long-term empirical evidence, early warning signals, and multiple drivers of regime shifts in a lake ecosystem（长期经验证据、早期预警信号和湖泊生态系统制度变迁的多重驱动因素）

A burgeoning literature shows that ecosystems (freshwater, marine and terrestrial) respond nonlinearly to environmental drivers, as an abrupt transition occurs when a driver exceeds a threshold (Beisner et al., 2003; Scheffer et al., 2001). Ecosystems often exhibit hysteresiseven when external drivers return to previous conditions, leading to not only serious degradation of ecological functions and services but also difficulty in restoration practice (Hilt et al., 2017).