中文摘要：

以广东省内第四纪红色黏土、玄武岩和花岗岩母质发育的土壤为研究对象，采集不同土地利用方式（水田、旱地、林地、果园/草地）下表层（0～15 cm）和亚表层（15～30 cm）土壤，研究土壤有机碳及其组分（腐殖质碳、易氧化有机碳）、土壤团聚体及其稳定性，分析土壤有机碳及其组分与土壤团聚体及其稳定性之间的相互关系。结果表明：土地利用类型、成土母质等影响土壤有机碳及其组分。3种母质发育的土壤中，各腐殖质组分占有机碳的比例是胡敏酸碳（HAC）＜富里酸碳（FAC）＜胡敏素碳（HMC），第四纪红色黏土母质发育土壤腐殖酸碳（HAC＋FAC）以草地最高、水田最低；玄武岩、花岗岩母质发育土壤腐殖酸碳以果园最高。土壤中易氧化有机碳所占比例均高于惰性态，第四纪红色黏土母质发育土壤易氧化有机碳占有机碳比例以草地最高、旱地最低；玄武岩、花岗岩为果园最高、林地最低。3种母质发育土壤团聚体（湿筛）主要以＜0.25 mm微团聚体为主，表层土壤＞0.25 mm团聚体所占比例、团聚体平均重量直径（MWD）、团聚体破坏率（PAD）大于亚表层。土壤有机碳各组分均随着有机碳质量分数的增加而增加，＞0.25 mm团聚体质量分数和团聚体MWD随着土壤有机碳及其组分质量分数的增加而增大；PAD随着土壤易氧化碳组分质量分数增加而降低，易氧化有机碳组分有利于土壤中形成较大的团聚体，并增加团聚体水稳性。

英文摘要：

Soil samples, derived from Quaternary red clay, basalt and granite, were collected from surface （0～15 cm depths） and subsurface （15～30 cm depths） in different land uses including paddy field, upland, forest land and grassland/orchard, and soil organic carbon （SOC） and its fractions （humus C, oxidizable C fractions）, soil aggregates and its stability, and their relationship were studied in this paper. The results indicated that land uses and soil parent materials affected SOC and its fractions. The rank of percentage of humic fractions was HAC＜FAC＜HMC in soils derived from three parent materials, Grassland had the highest percentage of HAC＋FAC, paddy field the lowest for soil derived from Quaternary red clay. Orchard had the highest percentage of HAC＋FAC for soil derived from basalt and granite. Soil labile organic C fractions was higher than inert organic C fractions, grassland had the highest labile organic C fractions, and upland the lowest for soil derived from Quaternary red clay;Orchard had the highest labile organic C fractions, and forest land the lowest for soil derived from basalt and granite. The percentage of＜0.25 mm micro-aggregate was dominated in soils derived from three parent materials, The percentage of＞0.25 mm aggregate, aggregate mean weight diameter（MWD） and percentage of aggregate destruction（PAD） in 0～15 cm depth soil were larger than those in 15～30 cm depth soil. The SOC fractions increased with the increase of SOC content; The percentage of＆gt;0.25 mm soil aggregate and soil aggregate MWD increased with the increase of SOC and its fractions; PAD decreased with the increase of oxidizable SOC fractions. Oxidizable SOC fractions favoured macro-aggregate formation, and increased water stable aggregation.