Why is an ecosystem considered to be a self supporting system

Why is an ecosystem considered to be a self supporting system?

An example of a ecosystem is a tropical forest and it is self supporting because the rain forest gas sunlight produce food from a process known as photosynthesis and then the animals eat the food which at one point be eaten by other animals.

do not just copy and paste. please rewrite it in your own words.

answer; ///the above statement is (true); //

answer; form new memories;