以吉林省前郭水田区为研究对象,空间尺度代替时间尺度方法,采用开发时间4~55 a共7个不同年限的土壤实测数据,研究1 m水田剖面土壤有机碳含量(SOC)的垂向分布规律,探讨近20年来水田土壤碳源、汇,估算了前郭水田土壤有机碳库储量,并结合吉林西部第二次土壤普查数据,进行不同土地利用类型土壤SOC的差异特征对比分析. 结果表明,水田SOC自上而下逐层递减,随着开发年限的增加总体呈增长趋势,表土层(0~30 cm)有机碳储量(1820.79 t)占1 m深土壤总有机碳储量(3885.05 t)的46.87%,不同土地利用类型的土壤有机碳密度(SOCD)差异很大,从大到小依次为水田、旱田、盐碱地,水田开发是一个SOC积累的碳汇过程,有利于实现有机碳由表土层向底土层的转移.
Taking Qianguo paddy field of Jilin Province as investigation object,based on the soil test data of 7 different periods developed for 4 to 55 years, the vertical distribution of SOC content in the 1 m paddy field section was studied adopting the space scale method instead of time scale. The paddy soil carbon sink in last 20 years was discussed and the organic carbon storage of Qianguo paddy field soil was estimated. According to the second soil census data, the characteristics of soil SOC used in fields of different type were comparatively analyzed. The results showed that the paddy field SOC decreased from top to bottom by layer, which showed an increasing trend with the increase of development age; the organic carbon content in the surface soil layer (0-30 cm) (1820.79 t) was 46.87% of the total organic carbon storage in deep soil (3885.05 t), and the soil SOCD content was highly different depending on the type of field, ranked in descending order as paddy field, dry land, and saline field. The development of paddy field is a SOC accumulating carbon sink process, which is conducive to the transfer of organic carbon from the surface soil layer to the bottom soil layer.