无论是利用森林的木材资源,或者是保护森林环境,改善人类的生活场所,掌握森林生态系统的实质,了解其物质的收支和循环动态,都是十分重要的。特别是从林业生产的角度,尽管森林不同于其他矿物资源,是一种可更新的资源,但是,为了永续利用森林,提高林业生产的水平,也必需对森林生态系统有一个正确的认识。树木群是构成森林生态系统的主要成分,而树木是高等植物,它接受太阳光能、热能, Whether it is using the wood resources of forests, protecting the forest environment, improving the living places of human beings, mastering the essence of forest ecosystems, understanding the balance of payments and the circulation of their materials, it is very important. Especially from the point of view of forestry production, though forests are renewable resources different from other mineral resources, a correct understanding of forest ecosystems is also necessary for the sustainable use of forests and the improvement of forestry production. The tree group is the main component of the forest ecosystem, and the tree is a higher plant, which receives solar energy, heat,