Answer:
A natural ecosystem is self sufficient and sustainable is it is allowed to be so.
Explanation:
The ecosystems have a cause and effect sequence to maintain equilibrium. If the state is disturbed, there will be cascading effects on the system which can lead to destruction of the resources.
Our ecosystem is naturally equipped with endurance. The systems have been productive since ages. With the increase in human activities opposing to the ecosystem, the level of endurance decreases.
If this continues, system will no longer be eco-friendly. To curb this, innovative methods need to be employed (to meet the current requirements) to convert the existing system to the eco-friendly model.