作　　者： ; ; ; ; ;

机构地区： 中国农业大学资源与环境学院

出　　处： 《土壤学报》 2014年第2期238-246,共9页

摘　　要： 为研究北京地区红色黏土的成土过程及其系统分类,选取6个发育在石灰岩类和花岗岩类母岩上的红色黏土剖面,研究了土壤剖面形态、理化性质、黏土矿物组成等,并分析了其成土条件和发生过程。结果表明:所有土壤剖面的土壤结构体面上均有黏粒胶膜,通体无石灰反应,铁的游离度高,活化度低。石灰岩类发育的红色黏土质地更细,其土壤黏粒游离铁较多,颜色更红,结构体团聚程度更强。花岗岩发育的红色黏土因含有大量难以风化的石英,因而含有较多的砂粒,结构体团聚程度较低。这些土壤形成过程中发生了强烈的黏化和铁质化作用,可以推断其是在古湿热气候条件下形成的。而目前土壤的pH呈微碱或中性,交换性盐基离子以Ca2+为主,盐基饱和度较高,则是受现代黄土降尘的影响,发生了复盐基过程的结果。在此基础上,依据《中国土壤系统分类检索(第三版)》确定的原则和方法,确定研究剖面分属于淋溶土纲下的4个不同亚类。 To study pedogenetic process and taxonomy of red clay in Beijing, six red clay profiles developed from granites and limestones were selected as samples for analysis of soil profile morphology, soil physical and chemical properties and soil mineral composition. Results show that argillan existed on the surface of soil ped of all the soil profiles, no lime reaction was observed throughout the profiles, and the soils were high in Fed/Fet and low in Feo/Fed. The red clay soil originated from limestones was finer in texture, higher in free iron, redder in color and higher in aggregation degree of the ped, while those from granites was lower in aggregation degree of the ped because of its higher content of sands of hard-to-weather quartz. During the pedogenetic processes of the soils, intensive argillation and ferruginization occurred presumably under hot and humid paleoclimate. However, with time elapsing, the red clays in the area have now become slightly alkaline or neutral in pH, dominated with Ca2 in exchangeable base and high in base saturation, as a result of modern loess precipitation and consequent base complication. According to the principles and methods of Chinese Soil Taxonomy （3rd edition）, the six red clay profiles should be sorted into four different subgroups of Argosols.

关 键 词： 北京 红色黏土 成土过程 系统分类

领　　域： [农业科学] [农业科学]