2001-2018年华北平原森林面积变化及影响因素分析

Changes of Forestland Area and their Influencing Factors in the North China Plain from 2001 to 2018

探讨华北平原森林转型缓慢的影响因素,可以为国家制定促进华北平原森林转型的政策措施提供科学依据.利用2001-2018年土地利用/覆被数据,分析华北平原森林变化时空特征.基于华北平原248个样本区县的自然与社会经济数据,构建线性回归模型,分析森林转型缓慢的影响因素.结果表明:(1) 18年间,华北平原森林转型进入面积净增加阶段,但进程仍然缓慢.林地面积增长的主要来源和流失的主要去向均为耕地和草地,林地与耕地两者之间转换频繁.(2)森林净增加的热点区域主要分布在山东中部丘陵地区、山东半岛沿海地区,森林净增加的冷点区域主要集中在淮北平原一带.(3)经济发展路径和国家森林政策路径在华北平原森林转型过程中作用不明显,其降水少而蒸发量大的自然条件、竞争性土地利用情况以及农业机械化发展是制约华北平原森林转型的主要原因.建议优化农田防护林带布局,实施更具针对性的林业政策和精细化的管理措施,加强对江苏黄淮平原一带林草一体保护,合理推动平原地区林业产业发展,协调好农、林业结构关系,实现粮食生产与生态环境建设的共同发展.

Exploring the influencing factors of the slow forest transition in the North China Plain(NCP) can provide a scientific basis for the formulation of policies and measures to promote the forest transition in the NCP. According to the MODIS land use and land cover data from 2001 to 2018, this study analyzed the spatio-temporal characteristics of forestland in the NCP by using land use transfer matrix and hot spot analysis method. Based on the natural and social economic data of 248 sample counties in the NCP, a liner regression model was constructed to analyze the influencing factors of the slow forest transition. The results showed that:(1) During the past 18 years, the forest transition in the NCP has entered the stage of net increase, but the process was still slow. The main source of forestland growth and the main direction of loss were arable land and grassland. Especially, the conversion between forestland and arable land was frequent.(2) The hot spots of the net increase of forestland were mainly concentrated in the central hilly area of Shandong Province and the coastal area of Shandong Peninsula, while the cold spots of the net increase of forestland were mainly concentrated in north Huaihe Plain.(3) Economic development path and national forest policy path played no obvious roles in the forest transition of the NCP. The natural conditions of low precipitation but high evaporation, competitive land use and agricultural mechanization development were the main reasons restricting the forest transition in the NCP. It is suggested to optimize the layout of farmland shelterbelt, implement more targeted forestry policies and refined management measures, strengthen the integrated protection of forest and grass in north Huaihe Plain, accelerate the development of forestry industry in plain area, coordinate the relationship between agriculture and forestry, and realize the common development of grain production and ecological environment construction.