植物是人类生存不可缺少的挚友。因为人们要生存就离不开衣、食、住、行，而这一切所需要的物质绝大部分是植物光合作用的产物。而植物对人类的贡献还远不只这些，它对环境的保护起着无与伦比的巨大作用。本文将从几个方面阐述绿色植物与环境保护的关系。气体循环中的作用... Plants are indispensable close friends of human existence. Because people want to survive can not do without clothing, food, shelter, transportation, and all this material is most of the products of plant photosynthesis. The contribution of plants to human beings is far from these, and it plays a tremendous role in the protection of the environment. This article will explain the relationship between green plants and environmental protection from several aspects. The role of gas circulation ...