长期种植绿肥稻田土壤颗粒有机碳演变特征  

Evolution characteristics of soil particulate organic carbon in the paddy field with long-term planting green manure

作　　者：刘立生[1,2] 徐明岗[1] 张璐[1,2] 文石林[1,2] 高菊生[1,2] 董春华[1,2] 

机构地区：[1]中国农业科学院农业资源与农业区划研究所,北京100081 [2]中国农业科学院衡阳红壤实验站祁阳农田生态系统国家野外科学观测研究站,湖南祁阳426182

出　　处：《植物营养与肥料学报》2015年第6期1439-1446,共8页Journal of Plant Nutrition and Fertilizers

基　　金：国家科技支撑项目(2012BAD05B05);公益性行业(农业)科研专项(201503122;201203030;201103005)资助

摘　　要：【目的】基于长期定位试验探讨长期冬种绿肥稻田颗粒有机碳演变特征与土壤肥力的关系。【方法】以中国农业科学院祁阳红壤实验站水田轮作制度长期定位试验为基础,测定了1982年至2012年每6年一次的历史土壤-样品的颗粒含量、颗粒有机碳含量和稻田土壤养分含量。试验设4个处理：1）稻-稻-冬闲（R-R-WF）：2）稻-稻--油菜（R-R-RP）：3）稻-稻-紫云英（R-R-MV）;4）稻-稻-黑麦草（R-R-RG）。晚稻收获后,采集0-20 cm耕层土壤。土壤颗粒分级采用改进的Anderson离心法得到砂粒（53-2000μm）、粗粉粒（5-53μm）、细粉粒（2-5μm）、粗粘粒（0.2-2μm）和细粘粒（〈0.2μm）。采用重铬酸钾法测定土壤颗粒有机碳含量。【结果】1）30年试验后三种绿肥处理稻田土壤有机碳在不同土壤颗粒中的分布表现为细粘粒（28.05-28.27 g/kg）〉粗粘粒（25.76-26.91 g/kg）〉细粉粒（12.80-14.52 g/kg）、砂粒（13.83-14.92 g/kg）〉粗粉粒（1.67-2.62g/kg）,与冬闲处理（R-R-WF）相比,土壤总有机碳、细粘粒有机碳和粗粘粒有机碳含量分别显著增加34.6%-42.4%、12.3%-13.2%、6.1%-10.9%砂粒有机碳含量显著降低26.2%-31.6%（P〈0.05）。2）30年试验后,三种绿肥处理稻田土壤总有机碳在不同颗粒中平均分布比例为粗粘粒有机碳（45.0%）〉细粉粒有机碳（25.8%）〉细粘粒有机碳（15.1%）〉砂粒有机碳（11.5%）〉粗粉粒有机碳（2.7%）,与R-R-WF处理相比,总有机碳在粗粘粒中的比例提高8.0%-12.8%在砂粒中的比例降低36.8%-42.9%在细粘粒、细粉粒、粗粉粒中的比例提高5.3%-6.1%、5.5%-6.4%、6.5%-8.1%。3）长期种植绿肥土壤总有机碳、粗粘粒有机碳、细粘粒有机碳含量与时间（年）呈现极显著线性正相关（P〈0.01）,累积速率分别为0.16 g/（kg·a）、0.31 g/（kg·a）、0.22 g/（kg·a）;砂粒有机碳、粗粉粒有机碳、细粉粒有机碳含量与时间�[Objectives]Evolution characteristics of soil particulate organic carbon and their relationship with soil fertility were studied based on a long-term paddy field experiment.[Methods]Based on a long-term paddy field experiment with different winter green manures located at Qiyang Red Soil Experiment Station,Chinese Academy of Agricultural Sciences,soil particulate,particulate organic carbon and soil nutrient contents of historical soil samples from 1982 to 2012 with 6 years＇ interval were analyzed.There were four treatments in this study,rice-rice-winter fallow,rice-rice-rape,rice-rice-milk vetch and rice-rice-ryegrass.Soil samples in 0-20 cm layer were collected after the harvest of late rice,and soil particle size fractionation with the Anderson centrifugal was conducted to get sand（53-2000 μm）,coarse silt（5-53 μm）,fine silt（2-5 μm）,coarse clay（0.2-2 μm）and fine clay（0.2 μm）.The contents of organic matter were determined by the potassium chromate method.[Results]1） After the 30 years＇ application of green manures,the contents of soil organic carbon in different soil particulates had the trends as：fine clay（28.05-28.27 g/kg） coarse clay（25.76-26.91g/kg） fine silt（12.8-14.52 g/kg）,sand（13.83-14.92 g/kg） coarse silt（1.67-2.62 g/kg）.Compared with the winter fallow,the total organic carbon in soil,the organic carbon contents in fine clay and coarse clay were increased significantly by 34.6%-42.4%,12.3%-13.2%and 6.1%-10.9%,respectively,while the organic matter contents in sand were decreased significantly by 26.2%-31.6%（P〈0.05）.2） The distribution proportion of soil organic carbon in different soil particulates after 30 years＇ green manure planting were：coarse sand（45.0%） fine silt（25.8%） fine clay（15.1%） sand（11.5%） coarse silt（2.7%）.Compared with the winter fallow,the proportions of organic matter were increased by 8.0%-12.8%in coarse clay,decreased by 36.8%-42.9%in sand,and elevated by 5.3%-6.1%,5.5%-6.4%and 6.5%-8.1%in fine clay,f

关 键 词：演变特征 颗粒有机碳 绿肥 稻田 

分 类 号：S153.6[农业科学—土壤学] S55[农业科学—农业基础科学]