Changes in Organic Matter Pools and Increases in Carbon Sequestration in Response to Surface Liming in an Oxisol under Long-Term No-Till
Changes in Organic Matter Pools and Increases in Carbon Sequestration in Response to Surface Liming in an Oxisol under Long-Term No-Till
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DOI：
10.2136/sssaj2011.0128
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发表时间：
2012-01-01
影响因子：
2.9
通讯作者：
dos Santos, Josiane Buerkner
中科院分区：
文献类型：
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作者：
Briedis, Clever;de Moraes Sa, Joao Carlos;dos Santos, Josiane Buerkner
在天然酸性土壤上的免耕系统（NTS）中，表面施石灰对中和土壤酸度和提高作物产量至关重要。因此，土壤表层的有机质（SOM）库可能会发生变化，反映作物残体增加C输入。本研究的目的是量化的变化SOM池和发生在响应表面石灰在长期NTS实验中的C螯合率。实验在巴西南部的Oxisol进行。处理包括1993年在土壤表面施用0或6 Mg ha（-1）白云质石灰，以及2000年在有或没有之前施用石灰的地块上重新施用0或3 Mg ha（-1）白云质石灰。石灰引起总有机碳（TOC）的积累，特别是在0至2.5厘米层。在对照、6 + 0、0 + 3和6 + 3 Mg ha（-1）处理中，20 cm土层中的TOC储存量分别为49.9、52.9、52.7和57.5 Mg ha（-1）。颗粒有机碳（POC）和矿物相关的有机碳（MAOC）在SOM的水平也提高了石灰。POC的增加直接相关（R-2 = 0.99，P = 0.002），从作物残体，这是在接受石灰处理的地块更大的C的积累。TOC与热水浸提碳、总多糖、活性多糖呈正相关。相关性分析还表明，TOC与POC的相关性更紧密，而不是与MAOC，表明更大的影响力的不稳定部分TOC的增加与表面石灰。
In a no-till system (NTS) on naturally acidic soils, surface liming is essential to neutralize soil acidity and increases crop productivity. As a result, the soil organic matter (SOM) pools of the soil surface layers may change, reflecting increased C inputs by crop residues. The objective of this study was to quantify changes in SOM pools and the rate of C sequestration that occur in response to surface liming in a long-term NTS experiment. The experiment was conducted in an Oxisol in southern Brazil. The treatments consisted of the application of 0 or 6 Mg ha(-1) of dolomitic lime on the soil surface in 1993 and a reapplication of 0 or 3 Mg ha(-1) of dolomitic lime in 2000 to plots with or without the previous lime application. Liming caused total organic C (TOC) accumulation, especially in the 0- to 2.5-cm layer. The amount of TOC stored in the 20-cm layer was 49.9, 52.9, 52.7, and 57.5 Mg ha(-1) in the control, 6 + 0, 0 + 3, and 6 + 3 Mg ha(-1) treatments, respectively. The levels of particulate organic C (POC) and mineral-associated organic C (MAOC) in the SOM were also enhanced by liming. The increase in POC was directly related (R-2 = 0.99, P = 0.002) to the accumulation of C from crop residues, which was greater in the plots receiving lime treatment. There were positive correlations between TOC and C extractable with hot water, total polysaccharides, and labile polysaccharides. The correlation analysis also demonstrated that TOC was more tightly correlated with POC than with MAOC, indicating a greater influence of the labile fraction on the increase in TOC with surface liming.