Why do we say that soil is the foundation of life?

im not gonna answer but i just saying that im the 1 that asked the question my name is sherif shehata and i am an Egyptian and i live in cairo, i go to the best skool in the Middle East BISC and im in year 7 today is the Friday 20th of November 2009 7:45 pm im doin my Biology hw and want the answer to this question im in my room on my desk and playing on my laptop just for anyone who knows me

PLS answer the question before monday 22nd of November because that's when i will hand it in so there will be NO point thnx :D