Humus Characteristics Of Main Soils In Hebei Province

Soil humus was an important component of organic matter, which was relatively difficult todegrade.The quantity and compositon of soil humus could reflect a certain soil conditions, soilprocesses, and could be an important diagnostic index to distinguish soil types. By field investigationand laboratory analysis, soil humus and its fractions of main soil types in Hebei province were studied.The paper studied humus and its fractions of8main soil types in Hebei from two aspects: soil surfaceand distribution of soil profiles. In additon, the paper analysised correlation between soilphysico-chemical properties and soil humus and its componentsin in different soil or differenthorizon.At the same time, using geostatistics, the paper studied the space structure of humus and itscomponents in topsoil in Hebei province.Moreover, the auther analysised regional differences of humusand its components of the broad distribution of brown soil, cinnamon soil, fluvo-aquic soil.The mainconclusions were as follows:(1) Surface and profile content features of humus and its component in8main types in Hebei.①Soil types had obviously effects on soil humus and its components in topsoil.The content of soilhumus and its components in meadow soil, black soil, chestnut soil and limestone soil were high, andcontent of soil humus and its components in brown soil, skeletal soil, cinnamon soil, and fluvo-aquicsoil were low. HA/HF ratio of cinnamon soil and skeletal soil were less than1. HA/HF ratio offluvo-aquic soil and limestone soil close to1, and HA/HF ratio of other soil types were greater than1.②For different soil types, profile distribution characteristics of average contentof soil humus andits fractions were different, and the absolute content of each component decresed with profile depthincreasing, but the change of relative ratio of components in different soils were various. The HA/HFvalue decreased with the depth increasing wavely, and were different in soils.The soil humuscomponents in each horizon were: humin>hummus acid> humic acid>fulvic acid.(2) The correlation between soil physico-chemical properties and soil humus and its components in8main soilsin Hebei provinces①CEC, sand had highly significant positive correlation with soil humus and its components, butsand had highly significant negative correlation with soil humus and its components, which indicatedthat soil humus and its components content had great effect on soil CEC、pH,while sand had certaineffect on soil humus and its componets mainly by improving the aeration and water permeability.②.The correlation between soil humus, humus components and soil property were different fordifferent horizon or soil types.Correlation between CEC, sand and soil humus, humus componentsincreased with soil depth increasing, and reached a maximum in the deposition layer.while sand hadsignificant correlation with soil layers above depositon horizon. In each soil, humus and its componentsof black soil, chestnut soil and meadow soil had greater correlation with soil properties.(3) Spatial distribution characteristics of oil humus and its components in Hebei province①Soils in Hebei province were various in the space, which was mainly caused by structuralfactors, and ratio of space structure were more than80%.②From the whole, distribution of soil humus and its components in Hebei province were: Fromthe northwest to the southeast, soil and its components were decreased annularly. While the distributionof HA/HF value was high in the north of Hebei,low in the south.③Except that humus and its componts in brown soil and fluvo-aquic soil were decreasingobviously from west to East or from north to south.Brown soil, cinnamon soil, fluvo-aquic soil in theother direction had no obvious change trend, the ratio of HA/HF had no significant change trend too.