【摘要】 以典型黑土区3种地貌类型区(漫川漫岗区、丘陵漫岗区、平原低地区)坡耕地不同坡位表层土壤为研究对象，通过测定土壤总有机碳、高活性有机碳、中活性有机碳和低活性有机碳等指标，分析黑土区坡耕地不同坡位表层土壤活性有机碳的变化特征，探究不同地貌类型区坡耕地土壤活性有机碳变化特征的差异。结果表明，坡耕地各坡位表层土壤总有机碳含量变化范围为26.57～38.61 g/kg,土壤活性有机碳含量变化范围为1.85～5.67 g/kg。3种地貌类型区坡耕地不同坡位土壤总有机碳和活性有机碳含量变化特征不同。漫川漫岗区总有机碳、中活性有机碳和低活性有机碳含量变化特征均表现为坡上和坡中显著大于坡下、坡上和坡中无显著差异；高活性有机碳含量变化特征则以坡中最高坡下最低，且不同坡位之间高活性有机碳含量差异显著。丘陵漫岗区不同坡位土壤总有机碳和低活性有机碳含量差异显著，并表现为坡下显著大于坡上、坡上显著大于坡中；高活性有机碳和中活性有机碳含量的变化则呈现坡上和坡下显著大于坡中、坡上和坡下无显著差异。平原低地区总有机碳及3种活性有机碳组分的含量在各坡位间的差异均为未达显著水平。不同地貌间典型黑土区坡耕地表层土壤活性有机碳分布规律有所差异，漫川漫岗区和丘陵漫岗区坡耕地土壤有机碳活性最差的坡位分别是坡下和坡中，而平原低地区不同坡位间无显著变化。研究结果为黑土坡耕地生态建设与保护技术的针对性设计奠定了理论基础。更多还原

【Abstract】 Taking the surface soil at different slope positions of sloping farmland in three typical types of landforms(overtopping and overtopping areas, hilly and overtopping areas, and plain low areas) in the black soil areas of Northeast China as the research object, the change characteristics of surface soil active organic carbon at different slope positions of slope land in black soil area were analyzed by measuring total organic carbon, highly active organic carbon, moderately active organic carbon, and low active organic carbon, exploring the differences in soil active organic carbon change characteristics of slope farmland in different landform types. The results showed that the variation range of total organic carbon content in the surface soil of slope farmland was 26.57-38.61 g/kg and the variation range of soil active organic carbon content was 1.85-5.67 g/kg. The change characteristics of total organic carbon and active organic carbon content in different slope positions of sloping farmland in three types of landforms were different. The variation characteristics of total organic carbon, medium active organic carbon and low active organic carbon content in the overtopping and overtopping areas were: slope up and slope middle significantly greater than slope down, and there was no significant difference between the slope up and slope middle. The variation characteristics of high active organic carbon content was the highest in slope middle and the lowest in slope down, and the high active organic carbon content was significantly different among different slope positions. The contents of total organic carbon and low active organic carbon in the hilly and overtopping areas were were significantly different at different slope positions, and the slope down was significantly greater than slope up, slope up was significantly greater than slope middle. The changes in the content of high active organic carbon and medium active organic carbon were: slope up and slope down significantly greater than slope middle, and there was no significant difference between slope up and slope down. The content of total organic carbon and three levels of active organic carbon in the plain low areas had no significant difference among different slope positions. There were differences in the distribution patterns of active organic carbon in the surface soil of typical black soil areas among different landforms. The slopes with the worst activity in the overtopping and overtopping areas and the hilly and overtopping areas were slope down and slope middle, re-spectively. There was no significant change between different slope positions in the plain low areas. The research results have laid a theo-retical foundation for the targeted design of ecological construction and protection technologies for black soil sloping farmland.更多还原