How can you sustain the environment without giving up basic necessities?

Wow, I see two answers that say there are 4 necessities....That part is correct, but their answers are only half correct.

Yes, there are four necessities for a human to survive...

1) Pure drinking water is your Most important asset. You won't last a week without it.

2) Shelter from the elements. Either a good quality tent or the knowledge and ability to build an adequate structure with materials at hand.

3) You must have the materials necessary to make fire in wet or dry conditions. A heat base is vital. If you have a fire...-100 degrees isn't fatal.

4) You must have a sustainable food source.

So...Companionship and weather issues don't count.

That depends on how you define necessities

Is it a necessity that you eat fresh cherries in December? Is it a necessity that you spend spring break in Thailand?.

Basic necessities, that is food , water , shelter and human companionship. Anything more that is luxury and energy intensive.

drastically reduce the human population

so is the intentions of the green movement

Try this link- http://www.environmentalscience.org/sustainability

By not going too greedy. Take what is necesary to survive, not more than that.

you only have four, food, shelter, companionship and a usable climate.