Organic matter application significantly influences soil carbon storage and sequestration in cropland. The investigation of C sequestration through soil organic carbon (SOC) fractions in the soil profile and its relation to nutrient stoichiometry are essential for evaluating the effect of farming practice on soil fertility. This study aimed to examine the effect of cattle manure application on nutrient stoichiometry, which would be associated with soil C stock in SOC fractions, such as microbial biomass C (MBC), dissolved organic C (DOC) and water-soluble organic C (WSOC), coarse particulate organic carbon (cPOC), fine particulate organic carbon (fPOC) and the mineral-associated organic carbon (MOC). A four-year manure application experiment was conducted in a Mollisol, in which fertilization treatments comprised (1) NoF: the non-fertilizer control, (2) F: synthetic fertilizer, i.e. 20.3, 21.2 and 12.2 kg ha⁻¹ of nitrogen (N), phosphorus (P) and potassium (K) in soybean, and 69.0, 28.1 and 6.1 kg ha⁻¹ of N, P and K for corn on an annual basis, respectively, (3) F + M: synthetic fertilizer plus 15 Mg ha^-1 of cattle manure and (4) F + 2M: synthetic fertilizer plus 30 Mg ha⁻¹ of cattle manure in a soybean-corn rotation. SOC concentration in top 10 cm of soil was 18 % and 19 % higher under F + M than that under NoF and F, respectively. Whereas, F+2 M significantly increased SOC concentration by 32 %, 32 %, 14 %, and 11 % in 0−10, 10−20, 20−30, and 30−40 cm of soil depth compared to that in respective soil depth under NoF. Compared to NoF and F, manure application (F + M and F+2 M) significantly increased MBC in the top 30 cm of soil depth and DOC concentration in the top 20 cm of soil depth, but significantly decreased WSOC concentration in the top 20 cm of soil depth. F+2 M significantly increased cPOC concentration in the top 30 cm of soil depth compared to NoF and F. F + M significantly increased fPOC concentration in the top 50 cm of soil depth, compared to NoF, and F. F+2 M further increased the fPOC concentration in the top 30 cm of soil depth, compared to F + M. There was no difference among fertilization treatments in MOC concentration in any soil depth. There were significant exponential correlations of C concentration in POC fractions with soil N, P and N/P ratio. These results indicate that the combination of manure and synthetic fertilizer increased C accumulation in the POC fraction especially in the top 30 cm of soil depth. The change of nutrient stoichiometry was responsible to the accumulation of soil organic matter, highlighting that N, rather than P mainly regulated C accumulation in POC. Increasing input of N fertilizer combined with manure application would benefit the formation of soil organic matter in agricultural Mollisols.

有机物的施用显着影响农田的土壤碳存储和固存。通过土壤剖面中土壤有机碳（SOC）组分的固碳研究及其与养分化学计量的关系，对于评估耕作方式对土壤肥力的影响至关重要。这项研究旨在检验牛粪肥对养分化学计量的影响，养分化学计量与土壤有机碳组分（例如微生物量碳（MBC），可溶性有机碳（DOC）和水溶性有机碳（WSOC）中的土壤碳储量相关），粗颗粒有机碳（cPOC），细颗粒有机碳（fPOC）和矿物相关有机碳（MOC）。在Mollisol上进行了为期四年的肥料施用实验，其中施肥处理包括（1）NoF：^-1的氮（N），磷（P），钾（K）在大豆，和69.0，28.1和6.1公斤公顷^-1上每年N，P和K的玉米，分别，（3）F + M：合成肥料加15 Mg ha ^-1的牛粪和（4）F + 2M：合成肥料加30 Mg ha ^-1大豆玉米轮作中的牛粪肥。在F + M条件下，土壤表层10 cm的SOC浓度分别比NoF和F条件下分别高18％和19％。而F + 2 M分别在0-10、10-20、20-30和30-40 cm的土壤深度中分别使SOC浓度分别增加32％，32％，14％和11％ NoF下的深度。与NoF和F相比，施肥（F + M和F + 2 M）显着增加了土壤深度前30 cm的MBC和DOC浓度在土壤深度前20 cm，但显着降低了前20 cm的WSOC浓度土深的厘米。与NoF和F相比，F + 2 M显着增加了土壤深度最深30 cm处的cPOC浓度。F + M与NoF和F相比，显着增加土壤深度最深50 cm中的fPOC浓度。与F + M相比，F + 2 M进一步增加了土壤深层顶部30 cm的fPOC浓度。在任何土壤深度下，施肥处理的MOC浓度均无差异。土壤中氮，磷和氮/磷比与土壤有机碳含量中的碳浓度呈显着的指数相关性。这些结果表明，肥料和合成肥料的结合增加了POC组分中的碳积累，特别是在土壤深度的前30 cm。养分化学计量的变化与土壤有机质的积累有关，这表明氮而不是磷主要调节POC中的碳积累。氮肥的增加与肥料的施用相结合，将有利于农业土壤中有机质的形成。在任何土壤深度下，施肥处理的MOC浓度均无差异。土壤中的氮，磷和氮/磷比与土壤有机碳含量之间存在显着的指数相关性。这些结果表明，肥料和合成肥料的结合增加了POC组分中的碳积累，特别是在土壤深度的前30 cm。养分化学计量的变化是造成土壤有机质积累的原因，这表明氮而不是磷主要调节POC中碳的积累。氮肥和肥料施用的增加将有利于农业土壤中有机质的形成。在任何土壤深度下，施肥处理的MOC浓度均无差异。土壤中氮，磷和氮/磷比与土壤有机碳含量中的碳浓度呈显着的指数相关性。这些结果表明，肥料和合成肥料的结合增加了POC组分中的碳积累，特别是在土壤深度的前30 cm。养分化学计量的变化与土壤有机质的积累有关，这表明氮而不是磷主要调节POC中的碳积累。氮肥和肥料施用的增加将有利于农业土壤中有机质的形成。土壤中氮，磷和氮/磷比与土壤有机碳含量中的碳浓度呈显着的指数相关性。这些结果表明，肥料和合成肥料的结合增加了POC组分中的碳积累，特别是在土壤深度的前30 cm。养分化学计量的变化与土壤有机质的积累有关，这表明氮而不是磷主要调节POC中的碳积累。氮肥和肥料施用的增加将有利于农业土壤中有机质的形成。土壤中氮，磷和氮/磷比与土壤有机碳含量中的碳浓度呈显着的指数相关性。这些结果表明，肥料和合成肥料的结合增加了POC组分中的碳积累，特别是在土壤深度的前30 cm。养分化学计量的变化与土壤有机质的积累有关，这表明氮而不是磷主要调节POC中的碳积累。氮肥和肥料施用的增加将有利于农业土壤中有机质的形成。养分化学计量的变化与土壤有机质的积累有关，这表明氮而不是磷主要调节POC中的碳积累。氮肥和肥料施用的增加将有利于农业土壤中有机质的形成。养分化学计量的变化与土壤有机质的积累有关，这表明氮而不是磷主要调节POC中的碳积累。氮肥和肥料施用的增加将有利于农业土壤中有机质的形成。