蜀南苦竹林生态系统碳储量与碳汇能力估测

Estimating the Carbon Stock and Carbon Sequestration of the Pleioblastus amarus Forest Ecosystem in Southern of Sichuan

科学准确的碳计量是评价森林减缓大气CO2浓度增加、应对气候变化能力的关键,而竹林特殊的生物学与生态学特性使得竹林碳汇计量较其他森林生态系统更为复杂。采用生物量法研究蜀南苦竹林生态系统的碳密度、碳储量及其空间分配格局,并对苦竹林生态系统碳汇能力进行估算。结果表明:1)立竹平均含碳率为450.792g·kg-1,不同龄级苦竹各器官含碳率差异不显著。土壤有机碳含量为19.410g·kg-1,不同土层差异极显著;2)苦竹林生态系统总碳储量为156.823t·hm-2,其中土壤碳库是最大的碳库,为132.568t·hm-2,占总碳储量的84.53%,枯落物碳库为最小的碳库(4.823t·hm-2),只占总碳储量的3.08%;3)苦竹立竹碳储量为19.432t·hm-2,占总碳储量12.39%,其中近半(49.13%)贮藏于竹秆中。竹秆、竹枝、竹叶3部分地上碳储量总计达13.346t·hm-2,占立竹总碳储量的68.68%,地上部分碳储量为地下部分碳储量的2.19倍;4)苦竹林生态系统植被层年固碳量为8.262t·hm-2,相当于每年固定30.294t·hm-2CO2,固碳能力强于毛竹。

Scientific and accurate estimation of the forest carbon sequestration is the key to evaluate forest functions of mitigating CO2 concentration in atmosphere and responding to climate change, however the special biological and ecological characters of bamboo greatly increased the difficulty in accounting the carbon sequestration. The biometric approach was used to estimate the carbon density, storage and spatial distribution pattern of the Pleioblastus amarus Forest Ecosystem in Southern Siehuan Province, as well as the annual carbon sink. The results showed： 1 ） There was not significant difference in carbon density between various ages and organs in stumpage bamboo, and the mean value was 450. 792 g·kg-1. The mean soil carbon density was 19. 410 g·kg-1, however there were extremely significant differences in the density between various soil layers. 2） The total carbon storage of the P. amarus forest ecosystem was 156. 823 t· hm-2, and the earbon stored in soil, stumpage bamboo and litter accounted for 84.5% （132. 568 t·hm-2） , 12.4% （19. 432 t·hm-2） and 3.1% （4. 823 t·hm-z） , respectively. 3） For the carbon storage in stand bamboo approximate 49.13% was stored in stem. The earbon stored in the over-ground parts and underground parts accounted for 68.68% and 32. 32% , respectively. The carbon stock above ground was 2.19 times more than that underground. 4） Carbon sequestration capacity of the P. amarus stand was 8. 262 t· hm -2a-1 , equivalents to 30. 292 t· hm -2 of CO2 , greater than Phyllostachys edulis forest ecosystem.