Effects of long-term fertilization on labile organic matter and carbon management index(CMI) of the typical soils of China Changes of soil nitrogen supply in black loessial in Loess Plateau under long-term fertilization The periodicities of water content and temperature variation for tomatoes in the cumulic cinnamon soils and the loessial soils Spatial and temporal variation of nitrous oxide concentrations in soil profiles of Manural Loessial Soil Effect of long-term fertilization on nutrient distribution in profiles of black loessial soil Effect of supplying C and N on the mineralization and priming effect of organic matter in loessial soil Effect of supplying C and N on the mineralization,immobilization and priming effect of soil nitrogen