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研究森林植被、枯落物和土壤的氮(N)磷(P)化学计量关系对于理解生态系统各组分的相互作用和养分循环具有重要意义。该研究对陕西省不同类型森林生态系统植被、枯落物和土壤的N和P含量及其化学计量关系进行了研究分析。结果表明:1)森林生态系统各组分的N、P化学计量特征存在显著差异(p<0.05),N、P含量均以林下灌草层植物和枯落物层较高,乔木层植物和土壤层较低;N:P值则稍有不同,以枯落物层最高,土壤层最低,其他各层差异不显著;各组分N、P含量和N:P值分别为0.72–11.99 mg·g~(–1)、0.47–1.07 mg·g~(–1)和1.86–14.84。0–1 m土层内N含量、N:P值均随土层加深而降低(p<0.05),P含量则不随土层发生明显变化。2)各组分N、P含量和N:P值多表现为阔叶林高于针叶林,但其差异不显著。3)生态系统同一组分内,N、P含量间极显著正相关,N、P含量与N:P值分别呈极显著正相关、负相关关系,但是土壤层内N、P含量无显著相关关系。各组分间,枯落物层与乔木层、草本层和土壤层的N、P含量和N:P值也均极显著正相关,而枯落物层与灌木层植物无显著相关关系。4)生态系统各组分N、P含量和N:P值随空间变化表现不尽一致,总体上呈稳态。该文通过对N、P化学计量特征的研究,揭示了森林生态系统植被、枯落物和土壤组分间所存在的养分循环联系,这些联系中也表现出分异特征,而分异可能由各自所执行的不同生态功能所致。
Studying stoichiometry of nitrogen (N) and phosphorus (P) in forest vegetation, litter and soils is of great importance in understanding the interactions and nutrient cycling of various ecosystem components. The study studied the relationship between N and P contents and their stoichiometry of vegetation, litter and soil in different types of forest ecosystems in Shaanxi Province. The results showed that: 1) The N and P stoichiometric characteristics of all components of forest ecosystem were significantly different (p <0.05), and the contents of N and P were higher in forest shrub layer and litter layer, And the soil layer is lower; the N: P value is slightly different, the litter layer is the highest, the soil layer is the lowest, the other layers are not significantly different; the N, P content and N: P values of each component are 0.72-11.99 The contents of N and N: P in the soil samples were decreased with the soil depth increasing (p <0.05 ), P content does not change significantly with the soil. 2) The content of N, P and N: P in each component were higher in broad-leaved forest than in coniferous forest, but the difference was not significant. There was a significant positive correlation and a negative correlation between N and P contents and N: P contents in the same ecosystem, but there was no significant correlation between N and P contents in soil layers relationship. The contents of N, P and N: P in litter layer, arbor layer, herb layer and soil layer were also significantly and positively correlated with each other, while the litter layer and shrub layer plants had no significant correlation. 4) The contents of N, P and N: P in different components of the ecosystem are not consistent with the spatial variation, and are generally steady. In this paper, we study the stoichiometric characteristics of N and P, and reveal the nutrient cycling relationships among the vegetation, litter and soil components of forest ecosystem. These associations also show the characteristics of differentiation and the differentiation may be caused by Respectively due to the different ecological functions performed.