How do natural disasters affect biodiversity?
If there is a flood, erosion cause some harm but make some positive changes
If a flood occurs (beyond floodplain), some areas will become saturated and aquatic life can bloom. Flooded areas can be better in the future since erosion brings organically rich material from upper basin. If there is a forest fire, succession might occur. First couple of years can be problematic in terms of animals and plants though. Nature can renew itself but if there are endemic plants/animals in the area of concern, they might disappear due to sudden change in the area.