研究若尔盖高寒嵩草草甸湿地常年积水、季节性积水(每年6-10月积水)和无积水3种水分条件下土壤有机碳的分布特征.结果表明:若尔盖高寒嵩草草甸湿地土壤有机碳含量极高,表土层(0 ～ 10 cm)最高可达73.2 g·kg-1,是中国森林、农田和草原生态系统土壤有机碳含量的6 ～10倍,且土壤有机碳的垂直分布深达400cm,远远超过中国森林、农田和草原生态系统；在浅土层(0～50 cm)和深土层(200～400 cm),不同水分条件下的高寒嵩草草甸湿地土壤有机碳含量差异显著(P＜0.05),在0 ～ 50 cm浅土层表现为常年积水区＞季节性积水区＞无积水区,在200 ～ 400 cm深土层表现为无积水区＞季节性积水区＞常年积水区,而在50 ～ 200 cm中间土层,不同水分条件下高寒嵩草草甸湿地土壤有机碳含量无显著差异(P＞0.05)；在0 ～ 400 cm土层,不同水分条件下的高寒嵩草草甸湿地土壤C/N值多小于15,这有利于高寒湿地土壤碳的积累；若尔盖嵩草草甸湿地的有机碳储量极高,常年积水区、季节性积水区和无积水区在0 ～ 400 cm土层的有机碳储量分别为64.87,71.21和76.45 kt· km-2,是中国森林、农田和草原生态系统的20 ～ 40倍；约60％的土壤有机碳储量分布在l m以下土层；整个若尔盖高原地区的高寒嵩草草甸土壤总有机碳储量约为0.245 Pg.%The soil organic carbon ( SOC) and carbon storage of Zoige alpine Kobresia meadows wetland under no water logging, perennial water-logging and seasonal water-logging( during June to October) conditions were studied. The results showed that the SOC of Zoige alpine Kobresia meadows wetland was extreme high and that in the surface layer of the soil (0-10 cm)reached to 73. 2 g·kg-1 , 6 - 10 times higher than the forest, farmland and grassland ecosystem in China. The vertical distribution reached to 400 cm under ground, which was far more than the forest, farmland and grassland ecosystem in China. There were significant differences (P＜0.05) in SOC between shallow soil layer (0-50 cm) and deep soil layer (200 -400 cm) over different hydrologic conditions. In the shallow soil layer (0-50 cm) the SOC rank was: perennial water-logging ＞ seasonal water-logging ＞ no water-logging, and in the layer 200 - 400 cm the rank was: no water-logging ＞ seasonal water-logging ＞ perennial water-logging, while in the soil layer 50 -200 cm there was no significant difference in the SOC (P ＞ 0. 05). In the soil layer 0 -400 cm, the C/N ratio of alpine Kobresia meadows wetland over different hydrologic conditions mostly was less than 15 , which was beneficial to the accumulation of soil carbon. The carbon storage of Zoig(e) alpine Kobresia meadows wetland was at a very high level, the soil carbon storage of perennial water-logging, seasonal water-logging and no water-logging was 64. 87 ,71. 21 and 76. 45 kt · km-2 respectively, which was 20 -40 times higher than the forest, farmland and grassland ecosystem in China. Approximate 60% of soil carbon storage distributed under the 1 m soil layer. The total soil carbon storage of Zoige alpine Kobresia meadows wetland was about 0. 245 Pg.
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