人需要空气、水和食物,成年人约在5周内没有食物、约在5天内没有水还能生存,但是没有空气只要5分钟就不能生存。
AboutUs.org (a wiki Internet domain directory) 对绿树网的评价是:"DoTree.com is a Chinese nature and environment friendly magazine", which is famous for its Carbon Footprint Calculator in China. The major concern of DoTree is to promote the green life style in China!
