Data synthesis of carbon distribution in particle size fractions of tropical soils: Implications for soil carbon storage potential in croplands
Data synthesis of carbon distribution in particle size fractions of tropical soils: Implications for soil carbon storage potential in croplands
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DOI：
10.1016/j.geoderma.2017.10.010
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发表时间：
2018-03-01
期刊：
影响因子：
6.1
通讯作者：
Chevallier, Tiphaine
中科院分区：
文献类型：
--
作者：
Fujisaki, Kenji;Chapuis-Lardy, Lydie;Chevallier, Tiphaine
土壤有机碳饱和度是指土壤有机碳(SOC)的理论最大值，土壤有机碳(SOC)可与细粉粒加粘土颗粒(F<；20微米)结合并稳定在其上。为了评价热带土壤的碳饱和度和估算农田的碳储存潜力，我们回顾了有关土壤有机碳在各组分之间分布的文献。我们收集了来自27个国家84个地点的258个热带土壤各组分间有机碳分布的数据点。我们使用边界线分析来估计最大稳定有机碳取决于土类、粘土类型和土地利用。用土壤有机碳饱和亏缺、实际有机碳含量与最大稳定有机碳含量之差来计算土壤有机碳储存潜力，发现热带土壤细粒中的最大有机碳含量(53g C kg(-1)细粒)低于以往以温带土壤为主的全球有机碳储存规模评估。森林土壤中的F<；20亩m比农田土壤中更接近有机碳饱和度。农田具有更高的土壤碳储存潜力，但改变农业管理做法并不能填补使用整个数据集计算的缺口。仅用草地或农田数据估算土壤有机碳亏损量要小得多：这为农田土壤有机碳储存潜力提供了一个更真实的估计。粗颗粒(F>；50亩m)中的有机碳含量不受土壤质地的影响，对总有机碳的贡献很大，尤其是沙质土壤(41.3%)。这受到农业管理做法变化的影响。我们的结论是，尽管提高SOC稳定性的目标最初源于气候变化缓解战略，但现在必须更多地将其视为与粮食安全和当地适应气候变化更相关。
Organic carbon saturation in soils refers to the theoretical maximum soil organic carbon (SOC) that can be associated with and stabilized on fine silt plus clay particles (F < 20 mu m). We reviewed the literature dealing with SOC distribution between soil fractions to evaluate carbon saturation for tropical soils and estimate the C storage potential of cropland.We collected 258 data points on SOC distribution between soil fractions in tropical soils from 84 sites in 27 countries. We used boundary line analysis to estimate the maximum stabilized SOC depending on soil group, clay type and land use. SOC storage potential was calculated as the SOC saturation deficit, the difference between the actual SOC content and the maximum stabilized SOC content.We found that the maximum SOC in the fine fraction of tropical soils (53 g C kg(-1) fine fraction) was lower than previous assessments of global SOC storage scale based mainly on temperate soils. The F < 20 mu m fractions were closer to SOC saturation in forest soils than in croplands. The cropland had a higher soil C storage potential, but changing agricultural management practices did not fill the deficit that is calculated using the whole dataset. The deficit was much lower when it was estimated with grassland or cropland data only: this provides a more realistic estimate for SOC storage potential for croplands.The SOC content in the coarser fraction (F > 50 mu m) did not depend on soil texture and significantly contributed to the total SOC, especially in sandy soils (41.3%). This is affected by changes in agricultural management practices. We concluded that, although the aim of increasing SOC stabilization originally arose from climate change mitigation strategies, it must now be more viewed as being more relevant to food security and local adaptation to climate change.