中文摘要：

海岸滩涂是一种特殊的土地利用类型，土壤有机质含量较低，固碳能力巨大。对海岸滩涂土壤有机碳时空变化规律进行研究，对于了解土壤碳库源汇转化、调节气候变化，具有重要的现实意义。本文应用地统计学与地理信息系统相结合的方法，结合《江苏省海岸线变迁图》，研究了东台市海岸滩涂近6000年以来不同土层（0～5cm、5-10cm、10～20cm、20～30cm、30-40cm、40～60cm、60～80cm、80～lOOcm、0-lOOcm）土壤有机碳含量的时空变化特征。结果显示：①研究区土壤有机碳平均含量变化范围为（2．0l～10．16）g／kg；②不同土层土壤有机碳呈现出强烈的空间自相关、中等强度的自相关以及恒定变异；③根据普通克里金插值结果，堤西地区的水稻土有机碳含量介于（5．75-16．87）g／kg，堤东地区的潮盐土有机碳含量介于（1．12-4．70）g/kg之间；④各剖面深度土层土壤有机碳含量呈现随土壤年代的更新而递减的条带状变化特征，并伴有局部化、斑块化等特征；⑤千年尺度下土壤有机碳含量年均变化值约为0．0017g／（kg·年），百年尺度下约为0．0055g／（kg·年），十年尺度下约为0．0048g／（kg·年）。该文研究表明，东台市海岸滩涂土壤有机碳含量随着围垦年限的减少、土层深度的增加而呈现递减趋势，并存在一定的时空变异性。

英文摘要：

Coastal saline soil is a special type of land use, which has a low content of organic matter and a high capacity of carbon sequestration. The study on the spatio-temporal variation of organic carbon in coastal saline soil has practical significance in understanding the transformation of soil carbon source and sink and regulating climate change. This study was carried out using geo- statistics and geographical information system （GIS）technologies to explore the spatio-temporal variability of soil organic carbon content in different soil layers（0-5, 5-10, 10-20, 20-30, 30-40, 40-60, 60-80, 80-100, 0-100cm）in Dongtai City since 4000 BC. We found 2.01-10.16 g. kg1 in the study area, and that different variation （strong, moderate or constant）was determined by the variation coefficient. According to geo-statistical analysis, strong spatial correlation was found in different layers of organic carbon and the value of the nugget effect varied from 0.01-0.51. The results of the ordinary Kriging demonstrated that soil organic carbon in the West Dike varied from 5.75-16.87 g·kg^-1, while the value in the East Dike varied from 1.12-4.70g·kg^-1. The soil organic carbon of Dongtai showed an increasing trend from beach to inland in whole soil layers. However, along with the increase in soil depth, soil organic carbon showed a banded decreasing trend with local characteristics and patches. Soil organic carbon content has a close relationship with soil depth, reclamation and fixed number of years, and land use. The average annual change in soil organic carbon content was 0.0017 g. kg^-1 at the Millennium scale, 0.0055g. kg^-1 at the centennial scale, and 0.0048g. kg^-1 at the ten-year scale. This study indicates that there is spatio-temporal variation of coastal soil organic carbon content, which decreased with reclamation time and soil depth.