论述了林学、森林与林业近两个多世纪以来的发展和变化 .林学经历了由传统林学向现代林学的转变 .现代林学是以森林生态系统的营建、经营管理和利用为研究对象 ,以发挥森林生态系统的生态环境功能为核心 ,全面发挥森林的多种效益和多种功能为目的的学科 .对森林的认识也经历了由单株树木到树木群体到森林生态系统的变化 .由于对林学及森林认识的深刻变化 ,人们对林业的认识也就从长期形成的以木材利用为中心 ,转变到以发挥森林生态系统的生态环境作用为核心和重点 ,全面发挥森林的生态、经济和社会功能作为林业的指导思想和目标 ,以实现林业的可持续发展 Discusses the development and changes of forestry, forestry and forestry since more than two centuries.The forestry has undergone the transformation from traditional forestry to modern forestry.Modern forestry takes the construction, management and utilization of forest ecosystem as the research object, The ecosystem function of forest ecosystem as the core and give full play to the multiple benefits and multiple functions of the forest for the purpose of the knowledge of the forest has also experienced from a single tree to the tree groups to the forest ecosystem changes.Because of the forest And the profound changes of forest cognition, people’s understanding of forestry has also shifted from taking the long-term use of wood as the core to taking the role of the ecological environment of forest ecosystems as the core and focus, giving full play to the ecological, economic and social functions of forests As the guiding ideology and goal of forestry, in order to achieve the sustainable development of forestry