关于森林的效益问题,人们的认识並不是固定不变的。最早,人们只是把森林当作薪炭的来源,后来,随着工业化的发展,木材的各种工业用途得到高度的发挥,而成为重要的原材料。在开发利用森林的同时,人们也逐渐认识到,森林还具有重大的防护效益。不过,就改造自然环境的防护效益方面,过去受人重视的森林水源涵养效益,水土保持效益,防风固砂效益,保护农田丰收等方面,而对于森林在净 With regard to the benefits of forests, people’s awareness is not static. At first, people only used the forest as a source of firewood. Later, with the development of industrialization, various industrial uses of wood were highly exerted and became important raw materials. While developing and utilizing forests, people have come to realize that forests also have significant protective benefits. However, in terms of improving the protective benefits of the natural environment, forestry conservation benefits, soil and water conservation benefits, wind-and sand-fixing benefits, and farmland harvest gains in the past have been emphasized. However,