开展珠三角森林城市群区域性河流水系森林景观评价与优化,为珠三角森林城市群森林质量提升与高质量发展提供理论依据。基于广东省2021年森林资源管理“一张图”数据,以地类、优势树种、年龄和郁闭度为依据进行景观类型划分与景观格局分析,其中优势树种分为桉树、阔叶混交林、其他阔叶林、杉木、针阔混交林、针叶混交林等6类。结果表明:珠三角森林城市群区域性河流水系森林景观多样性丰富,均匀度与连接度中等;森林景观斑块形状简单,以小斑块为主,斑块破碎化程度较大;森林景观以其他阔叶林为主,占比40.77%,桉树林次之,占比24.61%;郁闭度以中密度林为主,幼龄林、中壮林和成熟林的比例为1∶2∶1。建议通过高质量水源涵养林营造、低产低效林改造、中幼林森林抚育等森林质量提升项目,调整树种、龄组、密度结构,进一步优化森林景观的均匀度与连通性。

To carry out forest landscape evaluation and optimization of regional river system in the Pearl River Delta forest urban agglomeration is to provide the oretical basis for forest quality improvement and high-quality development of the Pearl River Delta forest urban agglomeration.Based on the data of "one map" of forest resources management in Guangdong Province in 2021,the landscape classification and landscape pattern analysis were researched in accordance with the land type,dominant tree species,age and density.Among them,the dominant species were divided into 6 categories:eucalyptus,broad-leaved mixed forest,other broad-leaved forest,Chinese fir,coniferous and broad-leaved mixed forest,and coniferous mixed forest.The results showed that the regional river system forest landscape in the Pearl River Delta forest urban agglomerations was rich in diversity,medium in evenness and connectivity,and the forest landscape patches were simple in shape,mainly small patches,and the patch fragmentation degree was high.The forest landscape was dominated by other broad-leaved forests,accounting for 40.77%,followed by eucalyptus forest,accounting for 24.61%,and the canopy density was mainly medium forest.The ratio of young forest,medium strong forest and mature forest was 1∶2∶1.Through forest quality improvement projects such as high-quality water conservation forest construction,low-yield and low-efficiency forest transformation,and middle and young forest tending,tree species,age group and density structure were adjusted to further optimize the evenness and connectivity of forest landscape.