Soil Carbon Library And Transformation Characteristics In Yutian Oasis Of The Keriya Valley

Soil carbon library were the largest and quickest turnover carbon reservoir in terrestrial ecosystems, it was composed of organic carbon and inorganic carbon library, and it plays an important role in global carbon cycle. At present, the interaction of environmental factors and human activities profoundly affect the carbon pool of migration and conversion, and coupled with global change and feedback mechanism. The research of soil carbon pools and conversion had become a hot area of soil circulation and global change. This paper takes Yutian Oasis of Keriya river watershed as a typical research area, based on the study of soil carbon pool characteristic and further discussed the relationship between factors of soil by correlation analysis and redundancy analysis. Through constructed the organic carbon mineralized model of soil that to fully reveal the transformation characteristic of soil carbon pool, and to provide a scientific basis for the research balance mechanism of terrestrial carbon. The main research conclusions were obtained:1. Conclusion the distribution characteristic of soil carbon library. Results indicated that, the distribution rule of soil organic carbon and soil active organic carbon content of different soil types was irrigated desert soil>saline soil>brown desert soil>aeolian sandy soil, the distribution rule of soil inorganic carbon was brown desert soil>saline soil>irrigated desert soil>aeolian sandy soil, the distribution rule of soil active inorganic carbon was saline soil>irrigated desert soil>aeolian sandy soil>brown desert soil. The distribution rule of soil organic carbon and soil inorganic carbon content in different soil layers was0-10cm>10-30cm>30-60 cm, the largest soil active organic carbon content in different soil layers was0-10 cm, and other layers was similar, the distribution rule of soil organic carbon and soil inorganic carbon content in different soil layers was10-30cm>30-60cm>0-10 cm.2. Get topsoil physical, chemical factors and enzyme activity variation regular pattern of different soil types in the oasis. The results showed that soil moisture was highest of irrigation desert soil, groundwater depth of irrigated desert soil was the most of shallow and aeolian sandy soil was the deepest, pH value and total salt of saline soil were the highest. Total soil nitrogen and available phosphorus of irrigated desert soil were the highest but variation regular pattern of available kalium was different, available Kalium of saline soil was the highest, available kalium of irrigated desert soil was the most of shallow; the highest soil enzyme activities were irrigated desert soil.3. The relationships between soil enzyme activities, soil physicochemical factors and soil carbon to be analyzed by traditional statistics and redundancy analysis(RDA). Soil moisture and bulk density were very significantly correlated with soil organic carbon and soil inorganic carbon; catalase, total nitrogen and ground water depth were significantly correlated with soil organic carbon and soil inorganic carbon. There was no significant correlationship between alkaline phosphatase, invertase and available Kalium and soil inorganic carbon. There was little correlationship between pH, total salt and soil organic carbon, soil inorganic carbon. The importance of soil enzyme activities and soil physicochemical factors to soil organic carbon and soil inorganic carbon could be arranged as bulk density > soil moisture > catalase > total nitrogen > ground water depth > available potassium > invertase > available Kalium > pH > total salt.4. Constructed the organic carbon mineralized model of soil. From the model we knew that the rule of the different types of mineralization in the soil. With the increased of soil depth, the mineralization rate of the irrigated desert soil and saline soil showed the trend of decrease. Brown desert soil of the mineralization rate showed 10-30cm>0-10cm>30-60 cm. Compared with other three types soil that the mineralization characteristics showed different in aeolian sandy soil, which mineralization rate emerged for 30-60cm>0-10cm>10-30 cm. For different soil of the mineralization regularity, the mineralization rate in 0-10 cm presented: aeolian sandy soil>irrigated desert soil>brown desert soil> saline soil. in 10-30 cm of soil the mineralization rate appeared: saline soil>irrigated desert soil>brown desert soil> aeolian sandy soil. the mineralization rate in 0-10 cm emerged: aeolian sandy soil>saline soil>irrigated desert soil>brown desert soil.