Micromorphological Features of Palaeocultivated Soil in Middle Reaches of Jinghe River
泾河中游古耕作土壤的微形态特征研究

A study on micromorphological features of soil in the middle reaches of the Jinghe River was carried out in this paper by means of field investigation,chemical analysis and polarizing microscope.The results are as follows: the texture of the palaeocultivated soil is medium-loam;the skeleton in the palaeocultivated soil have good smooth surface and mostly consist of quartzes,feldspars etc.,and also have some compounded quartz grains and platy single crystal of quartz or feldspar;there are residues of plants and directional distributed excrements in the organic constituents.The shapes of the voids chiefly are cylinder,arch or equidimension.The basic microstructure of the palaeocultivated soil is spongy microstructure.Hollow butt and wormholes are very developed with few crannies.The palaeocultivated soil accumulates an abundance of clays.It contains some pedogenic calcite pedofeatures and quantity of clay nodules impregnated by iron.The optical directional clay only exists a little.