阿尔泰山南坡土壤有机碳密度的分布特征和储量估算

Distribution characteristics and storage of soil organic carbon in the southern slope Altai Mountains

在陆地生态系统中土壤有机碳库是重要的碳库之一,对于研究全球碳循环和温室效应有重要影响。通过野外实地采样和室内分析,按照0~10 cm、10~20 cm、20~30 cm、30~40 cm、40~50 cm、50~100 cm的土壤分层方法,综合分析了阿尔泰山南坡土壤有机碳密度的分布特征,并估算了该地区的有机碳储量。结果表明：（1）在阿尔泰山南坡土壤有机碳密度随海拔梯度的变化具有一定的变化规律,海拔在500~2 400 m之间,土壤有机碳密度呈现逐渐增加的趋势;2 400~3 000 m之间,出现下降趋势;（2）土壤有机碳密度在0~100 cm土壤层内呈递减趋势,且不同土层有机碳密度的变异程度不同;在土壤各个土层深度,9种土壤类型的有机碳密度均有显著差异（p〈0.05）;（3）研究区域0~100 cm有机碳储量为0.477 4 Pg,各土壤类型储量差异显著（p〈0.05）,亚高山草甸土的储量最多,山地灰色针叶林土次之,储量最少的出现在高山寒冻土和棕钙土;其中0~30 cm层土壤有机碳储量为0.225 Pg,占总储量的44.13%。研究结果为估算不同土壤类型土壤有机碳密度,以及分析碳源碳汇提供了数据参考,并对进一步研究此地区碳循环具有一定意义。

Soil organic carbon stock is the main part of organic carbon stock in terrestrial ecosystems, may have im- portant effects on the global carbon cycle and global warming. In this study, by field sampling and laboratory analy- sis, the soil profile is divided into six layers： 0-10 cm, 10-20 cm, 20-30 cm, 30-40 cm, 40-50 cm, 50-100 cm. Comprehensive analysis of the distribution characteristics of the soil organic carbon density on the Ahai Mountains＇ southern slope. The results showed as follows ： （ 1 ）In this region, soil organic carbon densities have vertically distrib- uting regional characteristics, and organic carbon densities of different soil types are as follows： Brown calcic soil （11.29 ± 1.66） kg· m^-2, mountain brown calcic soil （16.02 ± 2.74） kg· m^-2, mountain chestnut soil （26.64 ± 3.38） kg· m^-2, mountain chernozem soil （65.79 ± 8.92） kg· m^-2, mountain gray coniferous forest soil （78.14 ± 9.34） kg· m^-2, mountain brown coniferous forest soil （74.48 ± 4.03 ） kg· m^-2, subalpine meadow soil （48.22 ± 5.06） kg. m-2, alpine meadow soil （59.94 ± 3.24） kg· m^-2, and alpine frost soil （21.29 ± 2.72） kg· m^-2. With the elevation increasing, from 500 to 2 400 m, soil organic carbon densities are gradually increased, from 2 400 to 3 000 m, are declined. （2） As far as 0-100 cm layer of soil profile, soil organic carbon densities are declined with soil depth increasing, and coeffi- cients of variation of soil organic carbon densities are not exactly the same in different layers; soil organic carbon densities of each layer are significantly different for different soil types （ p 〈 0.05）. （3） The soil organic carbon stor- age is 0.477 4 Pg, and different soil types＇ organic carbon storages have greatly varying （p 〈 0.05）. Sub-alpine meadow soils have the largest storage, followed by mountain gray coniferous forest soils;alpine cold permafrost and brown calcic soil have the least storage; 0.225 Pg being in the 0-30 cm layer, taking up 44.13% of the total storage. This study will provide the basic data of the organic carbon storage for the Ahai Mountains region, and provide a ref- erence about resource development and environmental protection at the same time.