开垦年限对稻田土壤腐殖质组成和胡敏酸结构特征的影响  

Composition of Humus and Structure of Humic Acid as a Function of Age of Paddy Field

作　　者：刘鑫[1] 窦森[1] 李长龙[1] 王培宇[1] 

机构地区：[1]吉林农业大学资源与环境学院,长春130118

出　　处：《土壤学报》2016年第1期137-145,共9页Acta Pedologica Sinica

基　　金：国家重点基础研究发展计划("973")项目(2011CB100503);吉林省重点科技攻关项目(20130206018NY)资助~~

摘　　要：以吉林省磐石市朝阳山镇青山村开垦年限分别为5 a、20 a和50 a的稻田土壤为研究对象,研究了0~15 cm和15~30 cm土层的土壤有机碳含量（SOC）、水溶性物质（WSS）、富里酸（FA）、胡敏酸（HA）和胡敏素（Hu）组成和HA结构特征及土壤养分含量的变化。结果表明：随稻田开垦年限增加（5~50 a）,表层（0~15 cm）与亚表层（15~30 cm）土壤变化如下：（1）电导率分别增加74.8%和113.7%,p H均基本稳定。土壤速效氮、有效磷和速效钾含量分别增加0.24%、15.8%、29.7%和1.33%、6.92%、14.7%。（2）有机碳总量分别增加42.1%和47.9%,WSS、HA和Hu含量分别增加28.4%、51.9%、76.2%和87.7%、84.9%、70.1%,而FA含量分别下降了9.2%和1.74%。说明稻田耕作年限越长越有利于土壤有机碳的积累。（3）胡敏酸占腐殖质的比例（PQ）值均增大,土壤腐殖化程度加深。（4）HA的氢碳元素物质的量之比（H/C）、色调系数（？lg K）、半定量分析得红外光谱在2 920和1 720峰处吸收强度之比（E2 920/1 720）与在2 920和1 620峰处吸收强度之比（E2 920/1 620）均减小,HA分子芳化度增强,缩合度上升,结构变得复杂。Relative to dry land,paddy field originally referred to artificially irrigated fields,where either paddy rice or upland crops were planted. Now only the field where paddy rice or some other aquatic plants are planted is called paddy field,or rice field. Different from the orginal paddy field,it has ridges to store water. In South China,paddy fields are not only long in cultivation history but also be vast in area and studies on such paddy fields started quite earlier and are great in volume both at home and abroad,but only a few has been reported on paddy soil in North China. Rice is the main grain crop in China. A large proportion of the total grain output in this country comes from Northeast China,where the paddy fields reach over 66.7 billion hm2（including 53.3 billion hm2 in Heilongjiang,and 6.6 billion hm2 each in Jilin and Liaoning）and occupy an important position in the rice cultivation area of the country. However,the rice fields are mostly short in cultivation history and most of the paddy fields were turned from upland fields,and what’s more,some of the paddy fields were turned back into upland fields again due to incomplete water conservancy facilities. During this kind of irregular changes,the soils in the fields would certain change in carbon fixation capacity,soil fertility and CO2 emission. But little has been done at home and abroad on how they evolve. Therefore,the study on paddy soils in Northeast China is of great significance. Rice yield depends mainly on soil fertility,of which soil organic matter is an important component. Soil humus,being an important component of the soil solid phase material,plays a huge role in the genesis and development of soil fertility,and hence is also an important indicator for soil fertility. It does not only influence productivity of the farmland ecosystem,but also have a great impact on CO2 concentration in the atmosphere through decomposition of soil organic matter. The study on how soil organic matter in the paddy field varies in content and composition

关 键 词：开垦年限 稻田 土壤有机质 腐殖质组成 胡敏酸 结构特征 

分 类 号：S153[农业科学—土壤学]