Ecological Stoichiometric Characteristics of Leaf-litter-soil of Different Afforestation Tree Species in Upper-river Basin of Miyun Reservoir
Plain afforestation may affect the stoichiometry of carbon,nitrogen,and phosphorus in soil due to chan-ges in land use.In order to clarify the spatial distribution,stoichiometric characteristics,and control factors of carbon(C),nitrogen(N),and phosphorus(P),four typical plain afforestation forests,Robinia pseudoacacia,Platycladus orientalis,Ailanthus altissima and Ulmus pumila,were selected in the upstream plain afforestation area of Miyun Reservoir,Beijing.Analyzed the concentrations and stoichiometric relationships of C,N,and P in leaves,litter,and soil.The results showed that the content of C,N,and P in the leaves,litter,and soil of different tree species showed changes.The C content of white elm was highest in the leaves,litter,and soil,and there were significant differences in the C︰N︰P stoichiometric ratio between fresh and fallen leaves of the four tree species.The fresh leaves of the four tree species showed a C︰N and C︰P ratio of Ulmus pumila>Robinia pseudoacacia>Ailanthus altissima>Platycladus orientalis.The N︰P ratio of fallen leaves of four tree species is as follows:Robinia pseudoacacia>Ai-lanthus altissima>Platycladus orientalis>Ulmus pumila,and there are significant differences among the three.There is a significant correlation(P<0.01)between soil C︰N,C︰P,N︰P,and SOC and TN content,indicating that the content of SOC and TN is a factor affecting the stoichiometric ratio of C,N,and P.The N/P of Robinia pseud-oacacia,Ailanthus altissima,and Ulmus pumila leaves in this area is 16-19,indicating that the growth of these three tree species may be limited by P.Therefore,in the management of artificial forest nurturing,understory vegetation should be protected.For coniferous forests,mixed forests should be appropriately developed to promote litter decom-position,improve the nutrient cycling ability of artificial forests,and maintain long-term productivity of the forest.
Miyun Reservoirafforestation tree speciesecological stoichiometric characteristicsrestriction element
万方数据
维普
