黄土丘陵区水蚀坡面土壤有机碳矿化动态模拟

发布时间：2019-05-28 07:51

【摘要】：为了深入理解侵蚀影响下的碳排放机制,本文以黄土丘陵区不同有机碳背景的水蚀坡面土壤为研究对象,采用3因素(土壤有机碳水平、温度和土壤含水量)4水平的正交试验设计,通过对坡面不同部位土壤的室内矿化培养实验,分析水蚀坡面土壤有机碳矿化特征,并模拟土壤有机碳矿化动态。结果表明:土壤有机碳质量分数是影响水蚀坡面有机碳矿化的主要因素,不同有机碳背景下,水蚀坡面表现出不同有机碳矿化特征。当土壤有机碳水平较低时,坡面侵蚀促进了沉积区土壤有机碳矿化;当土壤有机碳水平较高时,沉积区土壤有机碳矿化受到抑制。一级动力学方程较好的描述土壤有机碳矿化累积动态(R0.98),有机碳矿化潜力(Cp值)能综合反映土壤有机碳水平、温度和含水量对有机碳矿化的影响。通过Cp值修正,得到的土壤有机碳矿化多因素方程拟合度较高(R20.95),能够很好地拟合不同有机碳水平下土壤有机碳矿化动态。
[Abstract]:In order to deeply understand the carbon emission mechanism under the influence of erosion, this paper takes the water erosion slope soil with different organic carbon background in loess hilly region as the research object, and adopts three factors (soil organic carbon level). The orthogonal experimental design of temperature and soil water content was carried out to analyze the characteristics of soil organic carbon mineralization and simulate the dynamics of soil organic carbon mineralization in different parts of the slope. The results show that the soil organic carbon content is the main factor affecting the organic carbon mineralization on the water erosion slope, and the water erosion slope shows different organic carbon mineralization characteristics under different organic carbon background. When the soil organic carbon level is low, the slope erosion promotes the soil organic carbon mineralization in the sedimentary area, and when the soil organic carbon level is high, the soil organic carbon mineralization in the sedimentary area is restrained. The first-order kinetic equation can describe the accumulation dynamics of soil organic carbon mineralization (R0.98). The potential of organic carbon mineralization (Cp value) can comprehensively reflect the effects of soil organic carbon level, temperature and water content on soil organic carbon mineralization. Through the modification of CP value, the fitting degree of multi-factor equation of soil organic carbon mineralization is high (R20.95), which can well fit the dynamics of soil organic carbon mineralization under different organic carbon levels.
【作者单位】：中国科学院水利部水土保持研究所黄土高原土壤侵蚀与旱地农业国家重点实验室;中国科学院大学;西北农林科技大学林学院;
【基金】：国家自然科学基金“黄土高原深层土壤有机碳固存及对土地利用/覆被变化的响应”(41171422),“黄土区生物结皮坡面产汇流过程研究”(40971174) 中国科学院战略性先导科技专项“西北农田土壤固碳潜力与速率研究”(XDA05050504)
【分类号】：S153.621

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