黄土地区农田土壤块状结构体理化性状研究  

The physical and chemical properties of soil block cloddy in Loess area farmland

作　　者：王益[1] 王益权[1] 刘军[1] 张兴昌[1] 

机构地区：[1]西北农林科技大学资源环境学院,陕西杨凌712100

出　　处：《干旱地区农业研究》2007年第3期110-112,124,共4页Agricultural Research in the Arid Areas

基　　金："十一"五国家科技支撑计划重大项目"黄土高原水土流失综合治理工程关键支撑技术研究"(2006BAD09B06)

摘　　要：针对黄土地区农田土壤普遍存在块状结构体的现象,用蜡封法研究了块状结构体的松紧度以及用EDTA滴定法测定了结构体中水溶性Ca^2＋含量。结果表明不合理耕作所产生的块状结构体具有外部极为密实而内部相对疏松的构造特征,外壳的容重高达1.39-2.0 g/cm^3以上,仅依赖于自然干湿交替作用使其碎散成小的土团成为不可能,必须运用机械击打、旋耕切割等方法进行破碎。块状结构体在自然演变过程中,Ca^2＋存在着从结构体内部向外部迁移现象,帮助了密实外壳形成,也证明了环境因子对块状结构体性质有较为强烈的作用,耕作后及时破除这些块状结构体在农田管理中有着极端重要性。In Loess area, block cloddy was universal existence in farmland surface. The physical and chemistry properties of block cloddy in plow layer were researched in this study. The results showed that the structure characteristics of block cloddy was with tight surface but loose inner, the bulk density of the crust can be high as 1.39-2.0 g/cm^3, which was mainly affect by unreasonable tillage process. The tight surface can not be crushed by nature alternation of drying and wetting. Farming machinery to impact and rotary tillage were necessary when reduce them. Ca^2＋ can migration from block cloddy inner to surface during the environment evolution, which was deteriorated the block cloddy surface tight. It can verify the environment factor has great effect on the properties of block cloddy and disperse block cloddy after tillage is very important.

关 键 词：黄土地区 农田土壤 块状结构体 

分 类 号：S152[农业科学—土壤学]