Soil Physical and Chemical Characteristics of Sandy Meadow in Natural Restoration Process

The soil physical and chemical properties of sand meadow in natural restoring processes were studied.The results showed that enclosure promoted the improvement of soil physical and chemical properties.With the enclosure years increased,the soil particle composition changed significantly,the coarse particle size fractions(0.25 mm) decreased,but the fine particle size fractions(0.05~0.25 mm) increased significantly,and the clay particle size fractions(0.05 mm) also increased,especially in the top soil(0~10 cm).There were significant difference of organic carbon and total nitrogen content among different restoration status in each soil layer,the content of organic carbon and total nitrogen enhanced significantly in the restoring processes.With the enclosure years increased,the soil hardness increased accordingly,but the soil bulk density decreased.Correlation analysis revealed significant positive relationships between the soil carbon concentration,soil nitrogen concentration and soil fine particle size fractions(0.05~0.25 mm) and clay particle size fractions content,however,there was significant negative relationships between the soil carbon concentration,soil nitrogen concentration and soil coarse particle size fraction(0.25~2 mm) content.