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论文选择贵州省遵义县为典型样区,使用1980年代第二次土壤普查数据和2011年实测数据,以耕地土壤图为基础,运用土壤类型法和通用有机碳密度度量法,测算样区近30 a农田土壤有机碳(SOC)储量和密度变化特征,借助逐步回归分析法,识别影响这一变化的潜在驱动因素,结果表明:①样区近30 a农田总丢碳量2.94×104t,整体呈基本持平略带下降趋势;②样区近30 a农田单位面积碳变化量为-132.03 kg C·hm-2,年均变化速率-4.40 kg C·hm-2·a-1,固碳、丢碳和相对平衡面积比为49.45:32.96:17.59;③不同土壤类型间不管是SOC储量还是土壤有机碳密度(SOCD)均差异显著,丢碳幅度最大的是山地黄棕壤,达77.34%,固碳幅度最大的是紫色土,是1980年代的1.1倍;④空间分布上,总体展现为以娄山山脉为界的西北丢碳东南固碳态势;⑤SOCD1980s、机械组成(砂粒比、粘粒比、粉粒比)、全N密度、C/N等指标是影响样区近30 a间农田SOC变化的主要因素,且除SOCD1980s外,剩余5因素与SOCD年均变化速率间拥有正相关关系。研究有助于查明样区近30 a农田SOC变化的本底和潜在影响因素,为未来农田SOC的管理提供数据基础。
Zunyi County in Guizhou Province as a typical sample area, the use of the second soil census data in the 1980s and 2011 measured data, soil arable land map as the basis, the use of soil type method and common organic carbon density measurement method, the sample area of nearly 30 The results show that: (1) The total carbon loss of farmland in the past 30 years was 2.94 × 104 t, showing a general trend of With a slight downward trend; ②The change of carbon per unit area of farmland in the past 30 years was -132.03 kg C · hm-2, and the annual average rate of change was -4.40 kg C · hm-2 · a-1. Carbon and relative equilibrium area ratio is 49.45: 32.96: 17.59. ③The difference between SOC and SOCD is significant in different soil types, with the largest degree of carbon loss being mountain yellow brown soil, reaching 77.34% The carbon amplitude is the largest purple soil, which is 1.1 times that of the 1980’s; ④The spatial distribution generally shows the carbon sequestration in the southeast of the northwest of the Loess Mountains; ⑤SOCD1980s, mechanical composition (grit ratio, Grain ratio), all N density, C / N and other indicators are affected sample area In the recent 30 years, the main factors of farmland SOC change were the positive correlations between the remaining five factors and the average annual SOCD shift rate except SOCD1980s. The study is helpful to find out the background and potential influencing factors of farmland SOC change in the past 30 years and provide the data foundation for the future management of farmland SOC.