不同利用方式棕壤氧化铁的存在形态和分异特征

研究了不同利用方式下,棕壤各形态氧化铁的存在形态和分异特征。结果表明:(1)开垦使棕壤表层游离态、无定形态和结晶态氧化铁的含量都有一定程度的提高。(2)表层铁的游离度和活化度显示开垦促进表层游离铁形成并抑制其向晶质铁转化。(3)在土体剖面0~60cm范围内,各形态氧化铁均表现出向下聚集的规律,但它们在不同利用方式棕壤中的活动情况各不相同。它们的分布和转化与有机质和颗粒组成等多种因素有关,是一个复杂的多因素共同作用的过程。

The Existences and Characters of Iron Oxides in Brown Soil of Different Land Use Systems

Study was on the existing states and differential characteristics of three forms of the iron oxides different land use systems of brown soil. The results show: (1) the number of free iron oxides or active iron oxides or crystal iron oxides are different in the surface horizons of different land use systems. (2)the variation of free degree and activation degree show that till can promote the product of free iron oxides and hold back to form crystal iron oxides. (3) In the range of 0~60cm of the pedons, three kinds of iron oxides gathered downwards, but their mobility are different. The conversion and distribution of iron oxides related with organism and composition of particles is a compound process.