why do we need ecosystems
The reason we need to save or conserve an ecosystem is because they are all interdependent, if one ecosystem is thrown off balance it causes a domino affect down the food chain/web.e thus need to save the ecosystem that supports us inorder to save ourselves from the damage we did to the environment that gives us our food, clothing and shelter. As Walter Kelly said in the Comic Strip Pogo,  We have met the enemy and he is US ! . Source(s):