The objectives of this work were to quantify the soil organic carbon (SOC) stock and to evaluate the distribution of soil aggregates and their respective SOC and labile carbon (LC) present inside the aggregates in different perennial land use systems in the semi-arid region of Brazil. Soil samples were collected in four land use systems: two forage palm cultivation systems of different ages, a mango orchard, and natural forest. A higher amount of SOC stored in the 0–60 cm layer was observed in the mango orchard, increasing the soil carbon stock by 16.4% in relation to the natural forest. Palm cultivations presented larger amounts of macroaggregates from the 10–20 cm layer until 60 cm depth, while the mango orchard and natural forest presented a similar pattern in all fraction-size classes. SOC averages of non-occluded particulate organic matter (POM) and aggregate occluded organic matter (AOM) in the macroaggregates of the 0–10 cm layer were higher in the mango orchard and natural forest compared to palm cultivations; however, the LC of AOM was higher in palm crops. Soil microaggregates were little influenced by land use systems, however this class represented an average of 24% of SOC stock.

这项工作的目的是量化土壤有机碳（SOC）的存量，并评估半干旱地区不同多年生土地利用系统中土壤团聚体及其各自的SOC和不稳定碳（LC）的分布巴西的。在四个土地利用系统中收集了土壤样品：两个不同年龄的饲草种植系统，一个芒果园和一个天然森林。在芒果园中，在0–60 cm层中储存了更多的SOC，相对于天然林，土壤碳储量增加了16.4％。棕榈栽培从10–20 cm层到60 cm深度呈现出大量的大团聚体，而芒果园和天然林在所有分数级类别中均表现出相似的模式。与棕榈种植相比，芒果园和天然林中0-10 cm层大集合体中非封闭颗粒有机物（POM）和聚集有机物（AOM）的SOC平均值更高；然而，棕榈农作物的AOM LC较高。土壤微骨料几乎不受土地利用系统的影响，但是该类别平均占SOC总量的24％。