Effects of Mitigation Scenarios on Water Quality Under Drought-Flood Abrupt Alternation

With the increasing of extreme events globally, they had significant adverse impacts on ecosystems according to existing studies. Previous studies pointed out that the drought-flood abrupt alternation (DFAA) events have been increasing in recent years, and they had adverse impacts on eco-environment. To adapt the DFAA, mitigation measures should be applied. However, scant studies concern quantified assessment of these measures. Under these circumstances, this study set drought level degradation and flood level degradation scenarios in history and in the future based on the critical thresholds obtained by our previous field experiments in the Northern Anhui Plain. Our findings suggest that the soil P loss increased by 14.5–26.4%, and 0.5–1.3% under drought level degradation scenarios in history and in the future, while decreased by 40.0–41.7%, and −0.5 to 56.2% under flood level degradation scenarios in the summer maize planting areas. This study could provide supports for mitigating the adverse effects of DFAA on water quality, further may guide regulation measures for extreme events.