广东莲花山不同海拔梯度下森林土壤养分和化学计量特征

Soil Nutrients and Stoichiometric Characteristics along Altitude of Lianhua Mountain in Guangdong Province

为探究广东莲花山土壤有机碳(C)、氮(N)、磷(P)、钾(K)含量垂直分布特征,阐明土壤C、N、P、K生态化学计量学特征对海拔梯度的响应规律,在广东莲花山500~1 000 m区域以100 m海拔间隔进行研究。结果表明:(1)不同海拔下土壤有机碳、全氮、全磷、全钾变化范围分别是38.72~68.17、0.90~1.32、0.011~0.022、5.19~7.08 g·kg^-1,土壤全氮、全磷含量随海拔梯度升高而增加,土壤有机碳、全钾含量随海拔梯度的变化,差异不显著。(2)土壤的C/N和N/P分别介于40.12~50.76、43.06~90.86间。不同海拔梯段下土壤C/N无显著差异;整体来看,土壤N/P随海拔梯度的增加呈降低趋势。(3)500~1 000 m海拔土壤速效氮含量介于0.81~2.01 mg·kg^-1,均值为1.19 mg·kg^-1,其中,500 m海拔下土壤速效氮含量最高,1 000 m海拔下,土壤速效氮含量值达到最小。土壤速效氮含量与土壤速效氮含量的关系呈负相关。土壤速效钾、速效磷含量在500~800 m海拔间变化幅度较小,至900 m海拔下最大。莲花山土壤养分空间分布具有一定的异质性,全氮、全磷、速效氮含量、N/P的空间变化强烈。

In the current study,we evaluated the status of soil carbon(C),nitrogen(N),phosphorus(P)and potassium(K),and also the C,N,P ecological stoichiometry along the altitude within the range from 500 m to1 000 m(100 m altitude span)in Lianhua mountain.The results showed that the concentration of organic C,total N total P,total K at different altitude varied in the range of 38.72~68.17,0.90~1.32,0.011~0.022,5.19~7.08 g·kg^-1respectively.The content of total N and total P generally increased with increased altitude,while organic C and total K concentration had relatively little variation.Soil C/N ratio and N/P ratio varied between 40.12 and 50.7643.06 and 90.86,respectively.There was no significant difference in soil C/N ratio among the different altitude within 500 m to 1 000 m.In general,soil N/P ratio tended to decrease with the increased altitude.Soil available N ranged from 0.81 to 2.01 g·kg^-1 along the altitude of 500~1 000 m,with an average of 1.19 g·kg^-1.Along the altitude,soil available N tended to decline with rising altitude from 500 to 1 000 m.Soil available K and P were in the highest values at the altitude of 900 m,but fluctuates a little within the altitude of 500~800 m.