计划烧除对滇中云南松林土壤养分的影响OA北大核心CSTPCD

[Objective]This study aims to analyze the impact of evaluate prescribed burning and intervals on soil chemical stoichiometry of carbon(C),nitrogen(N),phosphorus(P),and potassium(K)in Pinus yunnanensis forest.[Method]The study object was P.yunnanensis forest in Xinping Zhaobi Mountain,Yuxi in central Yunnan Province.Soil samples of 0-10 and 10-20 cm soil layers were collected separately from unburned plots(control),plots of 1 year after prescribed burning(T1)and plots of 3 years after prescribed burning(T2),respectively,and the mass fractions of soil C,N,P,and K were measured.The impact of prescribed burning on soil stoichiometry in P.yunnanensis forest was studied.Analysis of variance(ANOVA),Spearman's correlation analysis and principal component analysis(PCA)were used to investigate the effects of different burning intervals on the soil stoichiometry.[Result]Compared with the control,there was no significant change in soil pH in both soil layers(0-10 and 10-20 cm)of T1 plot,while there was a significant increase in soil pH in both layers of T2 plot(P＜0.01).In the 0-10 and 10-20 cm soil layers of T1 and T2 plots,there was no significant variation in total carbon(TC),organic carbon(SOC),total nitrogen(TN),and hydrolysable nitrogen(AN).The available phosphorus(AP)in the 0-10 cm soil layer of T2 plot significantly decreased(P＜0.05),while the available potassium(AK)in both soil layers significantly increased(P＜0.05).The soil carbon-to-nitrogen(C/N)ratio significantly increased only in the 10-20 cm soil layer of T2 plot(P＜0.05).[Conclusion]The impact of the prescribed burning on the quality fraction of soil nutrients in the study area is influenced by such as factors burning interval and soil depth.Both interval time after prescribed burning has no significant impact on C and N contents of soil in P.yunnanensis forest.However,burning has a larger effect on soil pH,C/N ratio,AP,and AK.[Ch,3 fig.3 tab.34 ref.]