不同地点红锥幼林叶片-土壤C、N和P化学计量特征

Stoichiometric Characteristics of C,N and P in Leaves and Soils of Young Castanopsis hystrix Forests in Different Sites

为探讨不同地点红锥(Castanopsis hystrix)幼林叶片-土壤碳(C)、氮(N)和磷(P)的化学计量关系,以广西昭平县(FL)、兴业县(LW)、宁明县(PYS)、兴宾区(WD)和西乡塘区(LHL)5个地点的红锥幼林为研究对象,测定红锥叶片及土壤的C、N和P含量,分析其分配及化学计量特征,为红锥人工林的持续经营管理提供科学依据。结果显示,红锥幼林叶片平均C、N和P含量分别为465.8、12.1和0.68 g/kg;平均C∶N、C∶P和N∶P分别为39.9、821.0和21.1。0~60 cm土层土壤平均C、N和P含量分别为13.23、0.79和0.25 g/kg;平均C∶N、C∶P和N∶P分别为15.5、57.1和3.44。叶片与土壤C、N和P含量及化学计量比间均无显著相关性。各地均存在不同程度的营养缺乏;其中,PYS的红锥生长主要受N限制,WD、LW和FL的红锥生长主要受P限制,LHL的红锥生长受N和P共同限制。各地土壤可利用C、N和P均不足,建议增加土壤中有机质、N和P营养元素的投入。

In order to discuss stoichiometric relationships of C,N and P between leaves and soils of young Cas⁃tanopsis hystrix forests in different sites,five young C.hystrix forests were selected as research objects in Guangxi Zhaoping county(FL),Xingye county(LW),Ningming county(PYS),Xingbin district(WD)and Xixi⁃angtang district(LHL).Contents of C,N and P in leaves and soils of C.hystrix were determined,and their distri⁃butions and stoichiometric characteristics were analyzed,which could provide scientific basis for sustainable operation and management of C.hystrix plantations.Results showed that average contents of C,N and P in leaves of young C.hystrix forests were 465.8,12.1 and 0.68 g/kg,respectively.Means of C∶N,C∶P and N∶P in leaves were 39.9,821.0 and 21.1,respectively.Average contents of C,N and P in 0-60 cm soils were 13.23,0.79 and 0.25 g/kg,respectively.Means of C∶N,C∶P and N∶P in soils were 15.5,57.1 and 3.44,respectively.There were no significant correlations among contents of C,N and P,and their stoichiometric ratios between leaves and soils.Different levels of nutrient deficiency existed in all sites.C.hystrix growth in PYS was mainly limited by N.C.hystrix growths in WD,LW and FL were mainly limited by P.C.hystrix growth in LHL was lim⁃ited by N and P.Contents of available C,N and P were insufficient in all sites,so it was recommended to in⁃crease input of organic matter,N and P.