降雨强度对含碎石坡耕地侵蚀泥沙有机碳组分流失特征的影响OA北大核心

[Objective]The objectives of this study are to clarify the characteristics of organic carbon loss in sloping cultivated land with gravel under different rainfall intensities and gravel contents,and to provide scientific support for the prevention and control of organic carbon loss in sloping cultivated land.[Methods]The yellow-brown soil of sloping cultivated land with gravel was taken as the research object.Artificial simulated rainfall experiments were carried out with different rainfall intensities(60,90,120 mm/h)under four gravel contents(0,10％,20％and 30％).[Results](1)The content of fine sand particles was the highest(＞50％),the content of moderate-labile organic carbon was the highest in the erosion sediment,and the loss of organic carbon was the highest when the content of gravel was 20％,and the loss of moderate-labile organic carbon was the mainstay.(2)The rain intensity was significantly negatively correlated with the content of each organic carbon(p＜0.01),and the content of gravel and the content of no-labile organic carbon were significantly positively correlated(p＜0.05).(3)Rainfall intensity mainly affected the loss of organic carbon with high activity by affecting coarse sand and fine sand particles,while gravel content mainly affected the loss of organic carbon with low activity by affecting clay particles,and the influence of rain intensity(60.2％)on the loss of erosive sediment and organic carbon was greater than that of gravel content(39.8％).[Conclusion]The increase of rainfall intensity and gravel will accelerate the loss rate and amount of organic carbon,so it is recommended to de-gravel and keep the gravel content below 10％on sloping cultivated land.