【摘要】 为了解不同地形对青冈栎(Cyclobalanopsis glauca)林养分循环的影响,本研究对贵州茂兰国家级自然保护区内漏斗、槽谷、坡地3种地形青冈栎林叶片、凋落物、土壤中的碳(C)、氮(N)、磷(P)、C/N、C/P、N/P等化学计量指标进行测定和计算,分析植物叶片、凋落物、土壤的生态化学计量特征及其关联性。结果表明:(1)漏斗、槽谷、坡地3种地形青冈栎林叶片的C、N含量存在显著差异;凋落物中C含量存在显著差异;土壤C、N、P含量存在显著差异。(2)3种地形青冈栎林除叶片、凋落物C/N差异不显著外,其余均存在显著差异。(3)漏斗青冈栎林叶片N含量与凋落物C/N,叶片N/P与凋落物C/N、P含量,凋落物P含量与土壤N含量、N/P均呈正相关。槽谷凋落物C含量与土壤N含量呈正相关,与土壤C/N呈负相关;凋落物N含量与土壤C/N呈正相关,与土壤C、N含量及N/P均呈负相关;凋落物C/N与土壤N含量呈正相关,与土壤C/N呈负相关。坡地叶片N/P与凋落物N/P呈正相关,叶片C/N与凋落物N/P呈负相关;叶片C/N与土壤N含量呈正相关,与土壤C/N呈负相关。综上所述,随漏斗、槽谷、坡地地形的变化,青冈栎林生长受P限制有所加剧;漏斗、槽谷凋落物分解过程中受到N限制,坡地受P限制;青冈栎林土壤N释放较慢,土壤P含量相对丰富,但土壤P有效性较低,青冈栎林吸收土壤N、P不平衡。更多还原

【Abstract】 The effects of different terrains on the nutrient cycling in Cyclobalanopsis glauca forests were studied.The ecological stoichiometric indexes such as carbon(C),nitrogen(N),phosphorus(P),C/N,C/P,N/P in leaf,litter and soil samples in funnel,valley and slope areas of C.glauca forests in Maolan National Nature Reserve,Guizhou Province were measured.The ecological stoichiometric characteristics of leaves,litter and soil and their correlations were studied.The results are summarized as follows:(1)There were significant differences in leaf C and N content,litter C content,and soil C,N and P content among funnel,valley and slope areas.(2)There were significant differences in the C/P and N/P values of leaf,litter and soil among three terrains,while there was no significant difference in C/N value.(3)In the funnel area,positive correlations were observed for leaf N with litter C/N,for leaf N/P with litter C/N and litter P,and for litter P with soil N and soil N/P.In the valley area,litter C was positively correlated with soil N and negatively correlated with soil C/N.Litter N was positively correlated with soil C/N and negatively correlated with soil C,N,and N/P.Litter C/N was positively correlated with soil N and negatively correlated with soil C/N.In the slope area,leaf N/P was positively correlated with litter N/P;leaf C/N was negatively correlated with litter N/P and soil C/N and positively correlated with soil N.In summary,with the change of funnel,valley and slope terrains,the P limitation on the growth of C.glauca forests aggravated.The decomposition process of litter was limited by N in funnel and valley areas and by P in the slope area.The soil in the forests demonstrated slow N release,high P content,and low P availability,and the soil N and P absorption was unbalanced.更多还原