Effects Of Improvement Measures On Physicochemical Characteristics Carbon Pool Of Soda Meadow Alkaline Soil

The study was performed in Yangtai village of Zhaozhou county, Heilongjiang Province of China. Improving materials include chicken manure, cow dung and fresh grass, and the soil's pH was at 10. Eleven treatments were set including six composting, four split-plot, one Check. Soil characteristics such as soil temperature, soil moisture, soil salinity, soil pH, urease activity, hydrogeperoxidase activity were measured to evaluate the improving effects on soda meadow-alkaline soil. Soil organic matter, active soil organic matter, soil microbial carbon, soil respiration were also measured to evaluate the improving effects on the reclycling of soil carbon based on the previous work. In addition, Carbon Management Index (CMI) can be obtained from the calculation of soil organic matter content and the reactive soil organic matter, which not only reflect the influence of improving measures on the soil quality, but also the variation of soil organic matter content.The results showed that the treatments can improve the physical properties of soil, that is, by reducing soil temperature, increasing soil moisture and decreasing soil bulk density, and there is an interaction between organic materials (chicken manure,cow dung) and application ways of fertilizers on the soil bulk density in the split-plot experiment. After improvement, soil pH and soil salinity decreased, and the soil urease activity, soil hydrogeperoxidase increased significantly. The results of statistical analysis showed that soil enzyme activity for all treatments were all significanly higher compared with CK at 0.01 level.Measures of improvements exerted a significant influence on the soil organic matter, reactive soil organic matter, microbial carbon, soil respiration, shown by a higher soil organic matter content at 0.01 level on top soil and subtop soil. The microbial carbon, soil respiration increased too. The results of statistical analysis showed that the correlation between the microbial carbon and the soil respiration rate reached the 0.01 level. Soil organic matter content, reactive soil organic matter content and the soil respiration rate were highly correlated and reached the 0.01 level. Yet, for the composting treatment, soil organic matter content in the subtop soil layer were also highly correlated at 0.01 level.After calculation, CMI increased significantly, and the CMI decreased with soil depth. Every improvement measure increased significantly the CMI on the top ans subtop soil, but not on the third layer. The statistical results showed that CMI at top and subtop soil were significantly higher than that of CK treatment at the same layer.Take all factors into consideration, for composting treatment, effects of chicken manure are better than that of cow dung. For the same types of organic materials, the effect of improvement follws the following order: 5 cm> 3 cm> 1 cm. For the split-plot treatments, the effects of chicken manure were better than cow dung; and at 2 cm layer better than at than 1 cm layer, and there are interactions between organic materials and application ways of fertilizer, affecting together the determination of indicators.