4. what are some positive effects of a rapid change to an ecosystem

Positive effects of a rapid change to an ecosystem:There are some "positive effects" of a "rapid change" to an ecosystem. For example the increased food product in the ecosystem helps lots of people from getting out of the poverty.  The sudden change in ecosystem sometime causes adverse effect but some time it may help to bring the positive effect. As mentioned in the example the food increment which is an important change in ecosystem which helps lots of human race to get out from the poverty.

Migration people get up and go cause they feel it is best for them