【摘要】 以祁连山不同海拔梯度及剖面不同层次土壤有机质和全氮为研究对象,分析两元素在海拔和剖面上的分异规律。结果表明:祁连山青海云杉分布带(海拔为2 500~3 300m)土壤有机质和全氮含量随海拔的升高而增大,分布带下限两者含量最低,分别为8.07%和0.32%,分布带上限两者含量最高,分别为18.487%和0.588%。剖面上土壤有机质和全氮含量均表现为在表层最高,分别为18.487%和0.588%,在40-60cm层含量均最低,分别为7.373%和0.243%,随取样深度的增加,两者在剖面上的含量均呈递减趋势。土壤碳氮比随海拔的升高有波动增大趋势,海拔2 800m时最小,海拔3 100m时最大,其碳氮比介于12.1~30.6之间,在剖面上表现为表层最高,10-20cm最低,其余各层随土壤深度增加而增大。土壤容重与土壤全氮、土壤有机质含量之间均存在负相关关系;土壤自然含水量与土壤全氮、土壤有机质含量之间均存在正相关关系。更多还原

【Abstract】 The distribution characteristics of soil organic matter and total nitrogen at different altitudes and sampling depth in Qilian mountains were investigated.The results showed that soil organic matter and total nitrogen increased with the increase of altitude.Both soil organic matter and total nitrogen were the lowest at the lowest altitude,8.07%and 0.32%respectively,and were the highest at the highest altitude,18.487%and 0.588%respectively.Soil organic matter and total nitrogen at surface were the highest,18.487%and 0.588%respectively.The content at 40-60 cm was the lowest,7.373%and 0.243%respectively.Soil organic matter and total nitrogen increased with the decrease of sampling depth.Soil C/N increased with increasing altitude,ranged from 12.1to 30.6.Soil C/N at 2 800 maltitude was minimum,and at 3 100 maltitude was maximum.Soil C/N at 10-20 cm was maximum,and increased with the sampling depth from 60 cm.The soil bulk density was negatively correlated with total nitrogen and organic matter.Soil water content was positively correlated with total nitrogen and organic matter.更多还原