三峡库区典型人工防护林林分结构与固碳特征  

Characteristics of forest structure and carbon sequestration of typical artificial shelterbelts in Three Gorges Reservoir Area

作　　者：朱美菲 程金花[1] 师雪淇 史德威 马思文 ZHU Meifei;CHENG Jinhua;SHI Xueqi;SHI Dewei;MA Siwen(School of Soil and Water Conservation,Beijing Forestry University,100083,Beijing,China)

机构地区：[1]北京林业大学水土保持学院,北京100083

出　　处：《中国水土保持科学》2023年第3期119-127,共9页Science of Soil and Water Conservation

基　　金：国家自然科学基金“喀斯特地区土石二元结构下优先流对坡面水文过程影响机理”(32071839)。

摘　　要：人工植被建设是增加陆地碳汇、减缓大气CO_(2)浓度的有效措施之一。为明确三峡库区人工防护林的固碳增汇作用,选取杉木纯林(L1)、马尾松纯林(L2)、针叶混交林(L3)、阔叶混交林(L4)、针阔混交林(L5)5种典型林分类型为研究对象,采用基于林分蓄积量的生物量模型法,相关分析法对林分空间结构,碳密度特征及其影响因素进行分析。结果表明:1)研究区3种混交林均为中度混交及以上,林分胸径平均大小比数介于0.35~0.65之间,趋于中庸状态,阔叶混交林趋于亚优势生长,L2和L3呈随机分布,L1、L4、L5呈聚集分布;2)5种林分类型土壤有机碳为0.83~5.25 g/kg,L3和L4林地土壤有机碳含量较为丰富,碳密度(259.13 t/hm^(2))达全国平均水平,土壤层和植被层在碳库中所占比例较高。其中,L2和L5林分固碳能力显著,混交林在乔木层和枯落物层固碳方面明显优于纯林;3)土壤层碳密度受土壤密度和黏粒含量的影响,角尺度、聚集指数及大小比数对乔木层碳密度产生影响。研究区5种人工防护林有良好的固碳功能,林分结构对固碳功能具有调控作用。因此,通过调整林分空间结构实现对林地资源的调控,可以充分发挥人工防护林的固碳增汇功能。[Background]Artificial vegetation construction is one of the effective measures to increase land carbon sink and slow down atmospheric CO_(2) concentration.[Methods]In order to clarify the carbon sequestration effects of artificial shelter forests in the Three Gorges Reservoir area,five typical plantations including pure Cunninghamia lanceolate coniferous(L1),pure Pinus massoniana coniferous(L2),mixed coniferous forest(L3),mixed broad-leaved forest(L4),mixed coniferous and broad-leaved forest(L5)were selected as the research objects,the biomass model based on stand volume and correlation analysis were used to analyze the spatial structure,carbon density and its influencing factors.[Results]1)The 3 mixed forests in the study area were moderately mixed or above,the neighborhood comparison value ranged from 0.35 to 0.65,which was in the middle state.L2 and L3 were randomly distributed,while the other stands are in aggregate distribution.2)The soil organic carbon of the five forest types ranged from 0.83 to 5.25 g/kg,and it was rich in L3 and L4.The carbon densities(259.13 t/hm^(2))of the artificial shelterbelts were up to the national average level,soil and vegetation were the main carbon sequestration modes.The carbon sequestration capacities of L2 and L5 stands were significant,and the carbon sequestration capacity of mixed forest was significantly better than that of pure forest in tree layer and litter layer.3)The density of soil organic carbon was affected by soil bulk density and clay content,while the mingling degree,angular scale and neighborhood comparison had effects on the carbon density of tree layer.[Conclusions]The carbon sequestration function of 5 artificial shelterbelts in the study area was promising,and the stand structure may regulate the carbon sequestration function.Therefore,the function of carbon sequestration can be brought into full play by adjusting the forest spatial structure to regulate the forest land resources.

关 键 词：人工林 林分结构 碳密度 土壤有机碳 

分 类 号：S157.1[农业科学—土壤学]