A study of the aggregate structure of topsoil in Mu Us Sandland in China

The study and analyses of the structure of the topsoil aggregates is important to make informed decisions not only for the ecological restoration of the land, but also to prevent erosion of the topsoil. The aim of this study was to analyse the properties of the aggregates and their interdependencies at different depths of topsoil taken from the Mo Us region. The results illustrate that the diameter of the aggregates in the region measure between 0.25~0.50 mm. The contents of the aggregates differed with the depth and with biotope conditions. The maximum content of aggregates of size greater than 1 mm was seen in land covered with willow and Calamagrostis pigeios land constituted 4.27% and 3.55%, respectively. The analysis of the aggregate stability indicated that the soil in this region is not fully developed and is unstable. The soil structure appears to be gradually developing in the areas protected by vegetative cover or those that arerestoration areas, implying that organic matter is the most important factor influencing the occurrence and stability of aggregates in topsoil.