黔北金佛山方竹林碳储量及其影响因素

Carbon Storage in Chimonobambusa utilis Forest in North Guizhou Province and Its Influencing Factors

竹林碳汇是国际社会关注的热点,其中亚优势层竹林碳汇是观测研究的难点。在黔北大娄山金佛山方竹(以下简称方竹)中心分布区调查了92个样地,其中纯林样地数量占33.70%,分析了纯林及混交林碳储量及组成对方竹林分指标的响应。结果表明:1)纯林及混交林方竹地上部分平均碳储量分别为29.74 t/hm^(2)和30.31 t/hm^(2),地下部分平均碳储量分别为16.07 t/hm^(2)和18.16 t/hm^(2),总碳储量分别为45.81 t/hm^(2)和48.47 t/hm^(2),地下部分碳储量及总碳储量差异显著。不同类型方竹林构件碳储量呈竹秆>鞭根>竹叶>竹枝>竹篼的变化趋势,竹秆碳储量在龄级间比例相近。2)方竹纯林及混交林土壤(土层厚度40 cm)平均碳储量分别为136.36 t/hm^(2)和112.57 t/hm^(2),二者差异极显著,呈土壤B层>A层的变化趋势。土壤碳储量在A层与B层、A层及B层与AB层间相关极显著。3)方竹纯林及混交林灌木地上部分平均碳储量分别为0.01 t/hm^(2)和0.02 t/hm^(2),混交林乔木地上部分及凋落物平均碳储量分别为12.63 t/hm^(2)和2.14 t/hm^(2)。4)在纯林及混交林中,方竹碳储量、灌木地上部分碳储量以及植被层(方竹、乔木和灌木)地上部分碳储量与方竹平均胸径及密度二元线型回归式的相关性极显著,混交林方竹平均胸径及密度与土壤A层、B层及AB层碳储量的二元线型回归模型相关显著。研究为评价方竹林碳储量及影响因素提供了科学依据。

Bamboo forest sink is an international concern,among which the sink in subdominant layer is a difficult point in observation and research.In this study,92 plots were investigated in the main distribution area of Chimonobambusa utilis(hereafter referred to as CU)in North Guizhou Province of China,of which pure forest plots accounted for 33.70%.The response of CU stand indexes to the carbon storage in pure CU forest and mixed CU forest as well as to the composition of the storage was analyzed.The results show that:1)The average aboveground carbon storage is 29.74 t/ha and 30.31 t/ha,the underground carbon storage is 16.07 t/ha and 18.16 t/ha,and the total carbon storage is 45.81 t/ha and 48.47 t/ha in the pure CU forests and the mixed CU forests,respectively,and the underground carbon storage and the total carbon storage in the pure CU forests and the mixed CU forest are significantly different.The carbon storage of different components in Ch.utilis forest shows the trend of culms>rhizome>leaves and branches>bamboo basket,and the carbon storage in culms has the similar proportion along different age classes;2)The average soil carbon storage in pure CU forests and mixed CU forests(the total soil thickness at 40 cm)is 136.36 t/ha and 112.57 t/ha,respectively,with significant differences and the change trend of layer B>layer A.Soil carbon storage is significantly associated between layers A and B,A and B and AB;3)The average aboveground carbon storage in pure CU forests and the shrubs in the mixed CU forests is 0.01 t/ha and 0.02 t/ha,respectively,and the average aboveground carbon storage in arbors and litters of the mixed CU forests is 12.63 t/ha and 2.14 t/ha,respectively;and 4)Bamboo carbon storage,shrub aboveground carbon storage,and vegetation aboveground carbon storage(bamboo,trees and shrubs)in the pure CU forests and the CU mixed forests are extremely significantly correlated with the average DBH and the density binary linear regression of the CU forests,and the average DBH and the density of the CU mixed forests are significantly correlated with the binary linear regression of carbon storage in soil layer A,B and AB.The study provides a science base for evaluating the carbon storage of CU forest and its influencing factors.