雾灵山不同海拔土壤养分及其生态化学计量特征

Characteristics of soil nutrients and their ecological stoichiometry at different elevations in Wuling Mountain National Nature Reserve

为了揭示雾灵山不同海拔土壤养分含量变化及其生态化学计量特征,比较了雾灵山7个不同海拔的土壤有机碳(OC)、全氮(TN)、全磷(TP)、全钾(TK)、碱解氮(AN)、速效磷(AP)、速效钾(AK)含量变化及其生态化学计量特征,并对其相关性进行分析。研究结果表明,随土层加深,土壤OC、TN、TK、AN、AP、AK、C:N、C:P、C:K、N:P、N:K呈现显著下降趋势,且A土层显著高于C土层。土壤pH值、OC、TP、TK、AN、AP、C∶N、C∶P、N∶P和P∶K受海拔梯度显著影响;土壤OC含量呈“V”型变化趋势;土壤TP、TK含量主要呈现“M”型变化趋势;AN含量呈现“N”型变化趋势;pH值与AP含量呈波形变化趋势;C∶P,N∶P呈现“W”型变化趋势,P∶K呈现“M”型变化趋势,其他指标无显著变化趋势。主成分和相关性分析表明:OC与TN、TK、AK、C∶N、C∶P和C∶K均呈极显著正相关,说明有机碳是土壤养分的关键因子。综上所述,雾灵山保护区内土壤养分及其化学计量特征随海拔变异明显,土壤养分间具有一定的相关性。研究结果可为研究森林资源的保护和合理利用提供一定的参考。

In order to reveal the changes of soil nutrient content and its ecological stoichiometry characteristics obtained from different elevations in Wuling Mountain National Nature Reserve,the contents of soil organic carbon(OC),total nitrogen(TN),total phosphorus(TP),total potassium(TK),available nitrogen(AN),available phosphorus(AP),available potassium(AK)were compared.The results showed that soil OC,TN,TK,AN,AP,AK,C∶N,C∶P,C∶K,N∶P,N∶K decreased significantly with the deepening of soil layer,and soil layer A was significantly higher than soil layer C.Soil pH,OC,TP,TK,AN,AP,C:N,C∶P,N∶P and P∶K were significantly affected by the elevation gradient.The content of OC in soil showed a“V”-shaped trend;The contents of TP and TK in soil showed an“M”-shaped trend;The content of AN showed an“N”-shaped trend;pH value and AP content showed a wavy trend;C∶P,N∶P showed a"W"-shaped trend,and P:K showed an"M"-shaped trend;There was no significant change in other indicators.Principal component and correlation analysis showed that OC was positively correlated with TN,TK,AK,C∶N,C∶P and C∶K,indicating that organic carbon was the key factor of soil nutrients.In conclusion,soil nutrients and their stoichiometry characteristics in Wuling Mountain National Nature Reserve varied significantly with altitude,and there was a certain correlation between soil nutrients.The results could provide some reference for the study of forest resources protection and rational utilization.