长白山原始针叶林沼泽湿地生态系统碳储量

Carbon storage of a primary coniferous forested wetland ecosystem in the temperate Changbai Mountain of China

采用年轮分析及相对生长方程法与碳/氮分析仪测定法,测定温带长白山沿湿地过渡带环境梯度依次分布的5种典型原始沼泽类型(草丛沼泽-C、灌丛沼泽-G、落叶松泥炭藓沼泽-LN、落叶松藓类沼泽-LX和落叶松苔草沼泽-LT)生态系统碳储量(植被和土壤)、植被净初级生产力与年净固碳量,定量评价温带森林湿地固碳能力及其长期碳汇作用,并揭示其沿过渡带水分环境梯度的空间分异规律。结果表明:①5种天然沼泽类型的植被碳储量(3.18±1.70)—(112.2±18.3) tC/hm2沿过渡带环境梯度总体上呈递增趋势,针叶林沼泽显著高于C和G 12.2—34.3倍,G高于C 0.6倍,且LX和LT显著高于LN 0.3—0.6倍;②土壤碳储量(296.3±42.2)—(824.50±50.79) tC/hm2沿过渡带环境梯度总体上呈递减趋势,C显著高于G和针叶林沼泽30.8%—178.3%(P<0.05),G显著高于针叶林沼泽38.7%—112.8%,且LN和LT显著高于LX 32.8%—53.4%;③生态系统碳储量(408.42±57.53)—(827.52±50.96) tC/hm2沿过渡带环境梯度总体上也呈递减趋势,C显著高于G和针叶林沼泽30.2%—102.7%,G显著高于针叶林沼泽21.5%—55.6%,且LN和LT显著高于LX 18.8%—28.0%;④5种沼泽类型的植被净初级生产力与年净固碳量分布在(5.74±0.08)—(10.98±1.67) t hm-2 a-1和(2.44±0.03)—(5.17±0.83)tC hm-2 a-1,其中,LX和LT的植被净初级生产力显著高于C、G和LN 61.2%—91.3%和34.5%—59.6%;而在植被年净固碳量方面,3种针叶林沼泽类型均显著高于C和G 28.7%—111.9%和19.4%—96.6%。故长白山5种天然沼泽类型的植被净初级生产力与年净固碳量沿湿地过渡带环境梯度总体上呈现出阶梯式递增趋势,且仅有LX和LT达到了中国陆地植被及全球陆地植被平均固碳水平。因此,温带长白山沼草丛沼泽和灌丛沼泽长期碳汇作用强于森林沼泽,湿地碳汇管理实践中应重视草丛沼泽和灌丛沼泽的保护与恢复。

An annual ring analysis,relative growth equation method,and carbon/nitrogen analysis assay were used to determine the ecosystem carbon stocks(vegetation and soil)of five typical types of primitive swamps(Swamp Swamp-C,Shrub Swamp-G,Larix olgensis-Sphagnum magellanicum swamp-LN,Larix olgensis-moss swamp-LX,and Larix olgensis-Carex schmidtii swamp-LT)in the transitional zone of the wetland in the temperate zone of Changbai Mountain.The results showed that①The vegetation carbon stocks of the five natural swamp types were(3.18±1.70)—(112.2±18.3)tC/hm2,which increased gradually along the transitional zone.The conifer forest swamps had significantly higher values than did C and G by 12.2 and 34.3 times,respectively,G was higher than C by 0.6 times,and LX and LT were significantly higher than LN by 0.3 and 0.6 times;②The soil carbon stocks of(296.3±42.2)—(824.50±50.79)tC/hm2 declined along the environmental gradient of the transitional zone,C was significantly higher than that of G and the coniferous forest swamps by 30.8%—178.3%.Coniferous forest swamps were lower by 38.7%—112.8%,and LN and LT were significantly higher than LX 32.8%—53.4%;③The ecosystem carbon stocks of(408.42±57.53)—(827.52±50.96)tC/hm2 also showed a decreasing trend along the transitional zone,C was significantly higher than G and coniferous forest swamps by 30.2%—102.7%,and G was significantly higher than that of coniferous forests.Marsh was higher by 21.5%—55.6%,and LN and LT were significantly higher than LX by 18.8%—28.0%;④The net primary productivity and annual net carbon sequestration of vegetation in the five swamp types were distributed at(5.74±0.08)—(10.98±1.67)t hm-2 a-1 and(2.44±0.03)—(5.17±0.83)tC hm-2 a-1,of which,the net primary productivity of LX and LT was significantly higher than that of C,G,and LN by 61.2%—91.3%and 34.5%—59.6%.In terms of annual net carbon sequestration of vegetation,the coniferous forest swamp types were significantly higher than those of C and G by 28.7%—111.9%and 19.4%—96.6%.That is why the net primary productivity and annual net carbon fixation of the five natural marsh types in Changbai Mountain show a stepwise increasing trend along the environmental gradient in the transitional zone of wetlands.However,only LX and LT reached the average carbon fixation of land vegetation and global terrestrial vegetation in China.Therefore,the long-term carbon sink effect of the Changbai mountain marsh swamps and shrub swamps is stronger than that of forest swamps.We should protect and restore swamps and shrub swamps in our wetland carbon sink management practices.