长期连作茭白增加水田深层土壤有机碳的积累  

Increase of Organic Carbon Accumulation in Deep Soil of Paddy Fields by Long Term Continuous Cropping of Zizania latifolia

作　　者：张丽君 章明奎[2] ZHANG Lijun;ZHANG Mingkui(Pingyang County Agricultural Development and Agricultural Technology Guidance Station,Pingyang,Zhejiang 325400;College of Environmental and Resource Sciences,Zhejiang University,Hangzhou 310058)

机构地区：[1]平阳县农业开发和农业技术指导站,浙江平阳325400 [2]浙江大学环境与资源学院,杭州310058

出　　处：《中国农学通报》2024年第15期88-95,共8页Chinese Agricultural Science Bulletin

基　　金：国家自然科学基金面上项目“长期全年淹水集约种植对水耕人为土性态演变与物质循环及生态功能的影响”(41977001)。

摘　　要：为了解长期连作茭白后水稻土有机碳库及其组分的变化,选择了连续种植茭白时间分别为0(对照)、2~5、5~10、10~20、20~30、30~35 a等6组种植茭白前土壤类型相同的18块农田,通过挖掘标准土壤剖面采集0~20、20~40、40~60、60~80 cm分层土样,分析了土壤有机碳、不同稳定性有机碳组分和微生物生物量碳。结果表明:随着茭白种植时间的增加,土壤容重由上层至下逐渐下降;各土层中有机碳总量、高活性有机碳、中活性有机碳、低活性有机碳和惰性有机碳及微生物生物量碳均逐渐增加,增幅以20~40、40~60 cm等2个土层最为明显。同时,深层土壤中高活性有机碳比例呈现显著的增加,20~80 cm土层中有机碳总量及其各形态有机碳贮量占0~80 cm土层有机碳总量的比例逐渐增加,呈现有机碳向深层土壤积累的特点。分析认为,深耕、长期浸水及茭白生产过程田间人为频繁踩踏,导致土壤犁底层逐渐消失、软糊层形成是造成茭白田深层土壤有机碳快速积累、有机碳活性增加的主要原因。To understand the changes of organic carbon pool and its components in paddy soils after long-term continuous cropping of Zizania latifolia,six groups of farmlands with the same soil type,varying in Zizania latifolia plantation years of 0(control),2-5,5-10,10-20,20-30 and 30-35,were selected,and soil samples of 0-20,20-40,40-60 and 60-80 cm layers were collected.Soil organic carbon,different stable forms of organic carbon and microbial biomass carbon were analyzed.The results showed that with the increase of the plantation time of Zizania latifolia,the soil bulk density decreased gradually from the upper layer to the lower layer,the total amount of soil organic carbon,highly active organic carbon,moderately active organic carbon,low active organic carbon,inert organic carbon and microbial biomass carbon in each of soil layers gradually increased,with the most obvious increase in 20-40 and 40-60 cm soil layers.Meanwhile,the proportion of highly active organic carbon in deep soil increased significantly.The storage proportion of total organic carbon and various forms of organic carbon of 20-80 cm soil layers in all of 0-80 cm soil layers also increased gradually,showing the characteristics of organic carbon accumulation in deep soil.The main reasons for the rapid accumulation of organic carbon and the increase of organic carbon activity in the deep soil of farmland planted with Zizania latifolia were the gradual disappearance of the plough pan and the formation of the soft paste layer caused by deep tillage,long-term flooding and frequent human trampling in the field during the production of Zizania latifolia.

关 键 词：茭白田 深层土壤 碳库 有机碳组分 积累 软糊层 

分 类 号：S151[农业科学—土壤学]