9 Life-Support Systems for Humans.

I do not hold a position on any of these based on my own study, but I do recognize the potential catastrophic effects of not keeping an eye on these nine processes:

  1. Acid oceans (pH levels).
  2. Ozone (depletion).
  3. Fresh water (depletion).
  4. Biodiversity (extinction).
  5. Air cycles (nitrogen and phosphorus).
  6. Land resources (depletion).
  7. Climate control (change).
  8. Aerosol (loading).
  9. Synthetic chemical (pollution).

Source: https://www.newscientist.com/round-up/ocean-to-ozone-earths-nine-life-support-systems/