【摘要】 【目的】分析中亚热带不同树种、土层、粒级及其交互作用对土壤团聚体粒级组成及其碳、氮含量、储量及碳氮比的早期影响，揭示种植不同树种对土壤团聚体组成及其碳、氮含量的影响，以期为中亚热带地区造林和营林中合理选择树种提供科学依据。【方法】通过随机区组设计，于2012年2月在土壤发育和经营历史相同的林地上建立了中亚热带地区常见树种同质园。2019年8月测定各树种不同土层(0～10、10～20、20～30、30～40和40～50 cm)不同粒级(>2、1～2、0.25～1和0.053～0.25 mm)团聚体的质量百分含量、有机碳和全氮含量、储量及碳氮比。【结果】1)各土层团聚体均以>2 mm粒级为主，且>2 mm粒级团聚体的质量百分含量随土层加深而降低，并在木荷、米槠和杜英土壤中较高，而1～2 mm粒级团聚体的质量百分含量则在马尾松林土壤中最高；2)各粒级团聚体的有机碳含量随土层加深而降低，各土层团聚体的有机碳含量则随粒级减小呈先增后减的趋势，其中，0～10 cm土层团聚体的有机碳含量以1～2 mm粒级最高，而20～30、30～40和40～50 cm土层团聚体的有机碳含量则均以0.25～1 mm粒级最高，并在米槠林土壤中最高；3)除0～10 cm土层外，各土层不同粒级团聚体的全氮含量总体在米槠林土壤中最高，在香樟林土壤中最低；4)在20～30、30～40和40～50 cm土层，>2 mm粒级团聚体的碳、氮储量均在米槠林土壤中最高，而其余各粒级团聚体的碳、氮储量均在马尾松林土壤中最高；5)各粒级团聚体的碳氮比均在表层(0～20 cm)土壤较高，在深层(30～50 cm)土壤较低。【结论】各树种种植7年后，不同土层团聚体的粒级组成均以>2 mm为主，且>2 mm粒级团聚体的质量百分含量随土层加深而降低。土壤团聚体的碳、氮储量变化规律与粒级组成变化规律相似，土壤团聚体的粒级组成比团聚体碳、氮含量更能影响团聚体的碳、氮储量，所以种植米槠的土壤碳、氮储量比同期种植马尾松的土壤更高。更多还原

【Abstract】 【Objective】The objective of this study was to assess the early influence of plantations with different local tree species on the compositions of soil aggregates and their organic carbon and nitrogen concentrations and storage. This study was designed to provide more theoretical basis for rational selection of tree species in afforestation and forest management in subtropical China. 【Method】A common-garden planted with dominated tree species in central subtropical China was established in a forest stand with the same parent material and forest management through a randomized block design in February 2012. Soil samples were collected at different soil layers(0-10, 10-20, 20-30, 30-40, and 40-50 cm depths) at plantations of six tree species(Schima superba, Castanopsis carlesii, Elaeocarpus decipiens, Cinnamomum camphora, Cunninghamia lanceolate and Pinus massoniana) in August 2019. The particle size compositions(>2, 1-2, 0.25-1, and 0.053-0.25 mm), and their carbon and nitrogen concentrations, storage and carbon to nitrogen ratios were determined. 【Result】1) The dominated aggregate mass percentage was observed in >2 mm particles in all soil layers, and the mass percentage of >2 mm particles decreased with increasing soil depth. The mass percentage of >2 mm particles were the highest in soils planted with Castanopsis carlesii, whereas the mass percentages of 1-2, 0.25-1, and 0.053-0.25 mm particles were the highest in soils planted with Pinus massoniana. 2) The organic carbon concentrations in aggregates of all particle sizes decreased with increasing soil depth and the organic carbon concentrations in aggregates increased but then decreased with the decreasing particle sizes at all of the studied soil layers. The organic carbon concentrations in aggregates were the highest in the 1-2 mm particles for 0-10 cm soil layers, while those were the highest in 0.25-1 mm particles for 10-20, 20-30, 30-40, and 40-50 cm soil layers, with the highest concentrations observed in soils planted with Castanopsis carlesii. 3) The nitrogen concentrations in aggregates were the highest in soils planted with Castanopsis carlesii and the lowest in soils planted with Cinnamomum camphora for all particle sizes and soil layers. 4) The patterns of organic carbon and nitrogen storage were consistent with the variations of the compositions of soil aggregates at all soil layers. The organic carbon and nitrogen storage in the >2 mm particles were the highest in soils planted with Castanopsis carlesii, while those in the other particles with sizes less than 2 mm were the highest in soils planted with Pinus massoniana except for the 0-10 cm soil layer. 5) The carbon to nitrogen ratios in all aggregates were higher in surface soils(0-20 cm) but lower in deeper soils(30-50 cm). 【Conclusion】The compositions of aggregates at all of the studied soil layers was dominated by >2 mm particles, and their mass percentage showed decreasing tendency towards deeper soils after 7 years of plantation for all tree species. The mass percentage of >2 mm particles was the highest in soils planted with Castanopsis carlesii, while those for other particles with sizes less than 2 mm were the highest in soils planted with Pinus massoniana. Meanwhile, the carbon and nitrogen storage in aggregates were strongly controlled by the mass percentages of soil aggregates than by their concentrations in these particles. The soils planted with Castanopsis carlesii had higher carbon and nitrogen storage than the soils planted with Pinus massoniana.更多还原