前言掌握森林资源变化动态是评价森林质量和数量发展趋势的根据,也是确定森林经营方针,研究经营措施的依据。多年来由于森林资源管理机构和管理制度不健全,数出多门,各取所需,造成数据混乱,真伪莫辨,对工作带来极为不利。为 Preface Grasping the dynamic changes of forest resources is the basis for evaluating the development trend of forest quality and quantity as well as the basis for determining forest management policies and studying management measures. Over the years, due to the unsound management institutions for forest resources and the management system, they have taken countless numbers and taken their own needs, resulting in confusing data and indiscriminate authenticity, which is extremely unfavorable to the work. for