东北天然次生林物种多样性与碳储量关系研究

Research on the Relationship between Species Diversity and Carbon Storage of Natural Secondary Forest in Northeast China

本研究以东北地区天然次生林为研究对象,共调查样地71块(阔叶混交林36块、针阔混交林24块、蒙古栎纯林11块),研究不同林分类型下各林层物种多样性、碳储量以及二者之间的关系。结果表明:从各林分类型之间来看,针阔混交林内的物种多样性相对于其他林型更高,在各林分类型下,多样性指数均表现为草本层>灌木层>乔木层。各林分类型的单位面积碳储量为针阔混交林(144.12 t·hm^(-2))>阔叶混交林(106.85 t·hm^(-2))>蒙古栎纯林(77.53 t·hm^(-2)),在各林分类型下,乔木层碳储量在整个林分碳循环过程中占主要地位。随着各多样性指数的增加,林分植物碳储量呈现出先增加后降低的趋势,通过拟合发现,均以二次项函数拟合效果最佳,R^(2)值分别为0.6779、0.5643和0.5571。因此,在东北天然次生林经营过程中,可通过适当控制林分内多样性指数来提高植被碳储量,从而促进林分正向演替。

The natural secondary forest in Northeast China was taken as the research object in this study.A total of 71 plots(36 plots in broad-leaved mixed forest,24 plots in coniferous and broad-leaved mixed forest,and 11 plots in pure forest of Quercus mongolica)were investigated to study the species diversity,carbon storage,and their relationship in different layers of different stand types.The results showed that the species diversity in coniferous and broad-leaved mixed forests was higher than that in other types of forest.The diversity index of each stand type was as follow:herb layer>shrub layer>tree layer.The carbon storage per unit area of different stand types was as follow:coniferous and broad-leaved mixed forest(144.12 t·hm^(-2))>broad-leaved mixed forest(106.85 t·hm^(-2))>pure forest of Quercus mongolica(77.53 t·hm^(-2)).The carbon storage in the tree layer of each stand type played the major role in the whole carbon cycle process of forest.The carbon storage of forest plants showed the trend of first increasing and then decreasing with the increase of each diversity index.Through fitting,it was found that the quadratic function had the best fitting effect,and R^(2) values were 0.6779,0.5643,and 0.5571,respectively.Therefore,in the management process of the natural secondary forest in Northeast China,it was possible to increase vegetation carbon storage by properly controlling the diversity index in the stand,so as to promote the positive succession of the stand.