Even with land degradation being a serious issue, most cases can be avoided by individuals managing their own affairs in an orderly manner. We do not need a totalitarian organisation telling farmers what to do with their land.
The average collectivist greens person does not want to increase immigration either because of greed or prejudice. However, a larger population will preserve the environment if a system of private property rights is maintained.
Dr Bruce Ames is a scientist that has specialised in carcinogens and he has indicated that we consume trace amounts of deadly chemicals and we should vary our diet to ensure the exposure is remains small.