湖南省阔叶林生态系统碳储量及其分布

根据2017年湖南省森林资源清查资料和野外实地调查实测数据,对湖南省阔叶林生态系统碳储量、碳密度的动态特征进行了研究。结果表明:湖南省阔叶林森林生态系统总碳贮量为505.17 TgC,其中乔木层、灌草层、枯落物和土壤层层分别为113.75 TgC、9.92 TgC、9.64 TgC和377.86 TgC,分别占阔叶林生态系统碳贮量的22.52%、1.96%、1.91%和73.61%;湖南省阔叶林森林生态系统碳密度为154.51 t·hm^2,各层碳密度的大小顺序为土壤层(113.74 t·hm^-2)>乔木层(34.79 t·hm^-2)>灌草层(3.03 t·hm^-2)>枯落物层(2.95 t·hm^-2)。在3种类型阔叶林中,乡土阔叶林生态系统碳贮量为485.56 TgC,所占全省阔叶林生态系统碳贮量的96.12%;乡土阔叶林生态系统碳密度最大,为154.72 t·hm^-2,杨树林生态系统碳密度最小,为149.59 t·hm^-2。在阔叶林各龄组中,中、幼龄林约占湖南省阔叶林生态系统碳贮量的67.13%,是阔叶林的主要碳库且固碳潜力巨大;湖南省阔叶林碳密度幼龄林、中龄林、近熟林和成过熟林的碳密度分别介于24.60～55.51 t·hm^-2之间,具体表现为成过熟林(55.51 t·hm^-2)>近熟林(47.51 t·hm^-2)>中龄林(44.68 t·hm^-2)>幼龄林(24.60 t·hm^-2)。全省阔叶林生态系统空间分布表现为碳贮量呈现明显的湘西、湘南,湘中较低特征,而碳密度整体表现出洞庭湖流域地区大于其他地区的趋势。

Carbon storage and its distribution of broad-leaved forest ecosystems in Hunan Province

By using the resource inventory and field investigation data, this paper studied the characteristics of carbon storage and carbon density of broad-leaved forest ecosystems in Hunan Province in 2017. The total carbon storage in the broad-leaved forest ecosystems was 505.17 TgC, and the carbon storage in arbor layer, shrub-grass layer, litter layer, and soil were 113.75 TgC,9.92 TgC,9.64 TgC and 377.86 TgC, accounting for 22.52%,1.96%,1.91% and 73.61% of the total, respectively. The carbon density in the broad-leaved forest ecosystems was 154.51 t·hm-2, with 34.79 t·hm-2 in arbor layer, 3.03 t·hm-2 in shrb-grass, 2.95 t·hm-2 in litter layer,and 113.74 t·hm-2 in soil.In the three types of the broad-leaved forest ecosystems, the carbon storage of the native broad-leaved forest was 485.56 TgC, accounting for 96.12% of the total. the highest values of carbon density of the native broad-leaved forest was 154.72 t·hm-2, and the lowest values of carbon density was 149.59 t·hm-2.The young and middle aged forests which accounted for 67.13% of the total carbon storage were the main body of carbon storage in Hunan Province, the carbon density ranged from 24.60 t·hm-2 to 55.51 t·hm-2, the carbon density of young forest, middle-aged forest, near-mature aged forest and mature aged forest were 24.60 t·hm-2,44.68 t·hm-2,47.51 t·hm-2 and 55.51 t·hm-2. The carbon storage were greater in west and south area than in the north area of Hunan Province, and overall, the carbon density were greater in Dongting Lake plain than the forest in other area.