A major disturbance that almost caused a total collapse, but that the ecosystem was able to recover from eventually.​

A major disturbance that the ecosystem was able to recover completely from the grasses which is diseased.

Explanation:

If the grasses were diseased, the ecosystem will recover itself from this type of disturbance. If the population of snakes and hawks increases so the ecosystem will recover itself from this disturbance because snakes are the food of hawks so if the population of snakes increases so more food is available for hawks in the form of snakes and that's why population of hawks also increases and the population of snakes is controlled.