Herman Daly, one of the early pioneers of ecological sustainability, looked at the problem from a maintenance of natural capital viewpoint. In 1990 he proposed that:

"1. For renewable resources, the rate of harvest should not exceed the rate of regeneration (sustainable yield);
2. [For pollution] The rates of waste generation from projects should not exceed the assimilative capacity of the environment (sustainable waste disposal); and
3. For nonrenewable resources the depletion of the nonrenewable resources should require comparable development of renewable substitutes for that resource.

Herman Daly, one of the early pioneers of ecological sustainability, looked at the problem from a maintenance of natural capital viewpoint. In 1990 he proposed that;

1. For renewable resources, the rate of harvest should not exceed the rate of regeneration (sustainable yield);

Explanation:

Herman Daly talked about renewable energy. that the rate of consumption should not be greater than the rate at which the products are beo=ing produced.

A renewable resource this  is a natural resource that will be made to replace the portion that was used by consumption, either through natural reproduction process or by other artificial recurring processes in a finite amount of time.

heat from the core of the earth causes convection currents to occur in the mantle. these currents slowly move the crust around.