小陇山林区日本落叶松人工林碳汇研究

Carbon Sink of Larix kaempferi Plantation in Xiaolongshan Forest Area of Gansu Province

为科学评价甘肃省小陇山林业实验局日本落叶松人工林碳汇现状,采用标准地调查法、径级标准木法测定日本落叶松人工林乔木层生物量,样方法调查灌木层、草本层、林下凋落物生物量;采用重铬酸钾—硫酸氧化法测定乔木层、灌木层、草本层、凋落物层含碳率;用重铬酸钾水合加热法测定土壤碳含量;应用最新二类资源数据测算碳储量等方法,对小陇山林区日本落叶松人工林碳储量及其在乔木层、灌木层、草本层、林下凋落物以及土壤中的分布进行了测定研究。结果表明:小陇山林区日本落叶松人工林总碳储量为3380539.3 t,平均碳储量87.5 t·hm^(-2)。土壤、林下凋落物、乔木层、灌木层、草本层碳储量分别为2902920.3、56816.6、388531.5、24721.0、7549.9 t,分别占总碳储量的85.9%、11.5%、1.7%、0.7%、0.2%。总体看,土壤是日本落叶松人工林最大的碳库,乔木层是地上最大的碳库。按林龄分,本林区日本落叶松幼龄林、中龄林、近熟林林分碳储量分别为2509492.7、734499.6、136547.0 t,分别占总碳储量的74.2%、21.7%、4.1%,日本落叶松人工林碳储量以幼龄林为主,后期增长潜力巨大。

The biomass of tree layer of Larix kaempferi plantations of different ages was determined by standard plot method and diameter class standard wood method.The biomass of shrub layer,herb layer and litter under the plantations was investigated by sampling method.The carbon content of tree layer,shrub layer,herb layer and litter layer were determined by potassium dichromate and sulfuric acid(K_(2)Cr_(2)O_(7)-H_(24))oxidation method.The carbon content of soil was determined by potassium dichromate hydration heating method.The forest management planning data was used to calculate the carbon storage of Larix kaempferi plantation in Xiaolong mountain forest area of Gansu Province.The results showed The total carbon stock of Larix kaempferi plantation in Xiaolongsha is 3380539.3 tons,and the average carbon stock per hectare is 87.5 tons.The carbon reserves of soil,undergrowth litter,tree layer,shrub layer and herb layer was 2902920.3t,56816.6t,388531.5t,24721.0 t and 7549.9t respectively,which accordingly accounting for 85.9%,11.5%,1.7%,0.7%and 0.2%of the total carbon reserves.Soil was the largest carbon pool of Larix kaempferi plantation,and arbor layer was the largest carbon pool above ground.According to the stand age,the carbon reserves of young,middle and near mature forests in this forest area was 2509492.7t,734499.6t and 136547.0t,respectively.The carbon reserves of Larix kaempferi plantation in this forest area account for 74.2%,21.7%and 4.1%respectively.74.2%of carbon reserves of Larix kaempferi plantation in this forest area are stored in young forest.The carbon storage of Larix kaempferi plantation in this forest area has great potential for growth in the later period.