中文摘要：

2012年8月,在新疆博斯腾湖13个站点进行表层沉积物采集,分析无机碳及其碳、氧稳定同位素的含量和空间分布特征,探讨该湖表层沉积物无机碳（TIC）的空间变化影响因素.结果表明：2012年,博斯腾湖表层沉积物TIC含量平均值为5.5%,变幅为3.8%~9.8%,而δ^13Ocarb和δ^18Ocarb平均值分别为0.71‰和-4.4‰,范围为-0.23‰~2.27‰和-5.53‰~-2.55‰.从空间来看,湖泊北岸TIC值明显高于南岸,最高值出现在湖泊西北部的黄水沟水域,而河口区和湖心区最低.总体上,博斯腾湖表层沉积物TIC主要是湖泊自生的,其空间分布主要受开都河、黄水沟等入湖河水的影响,导致水体矿化度和营养盐的空间差异,进而影响了碳酸盐的析出与沉淀.另外,湖泊局部的水动力条件也影响TIC的保存与分布.δ^13Ocarb与δ^18Ocarb的极显著正相关说明近几年博斯腾湖封闭程度较好,尤其是东部大湖区,属于封闭环境碳酸盐沉淀.

英文摘要：

In this paper,we evaluated the sources and spatial variations of inorganic carbon in the surface sediments of Lake Bosten and explored the influencing factors. The samples were collected at 13 sites in the main section of the Lake Bosten in August,2012,using a Kajak gravity corer. The sampling sites covered most parts of the lake,with water depths from 3 m to 14 m. Total inorganic carbon（ TIC）,stable carbon and oxygen isotopic composition in carbonate（ δ^13Ccarb δ^18Ocarb） were analyzed. Our data showed that the contents of TIC ranged from 3. 8% to 9. 8%,with an average of 5. 5%. The analysis of the stable carbon and oxygen isotope composition of carbonate from the surface sediments showed the values of δ^13Ccarband δ^18Ocarbwere from- 0. 23‰to 2. 27‰（ 0. 71‰） and from- 5. 53‰ to- 2. 55‰（- 4. 4‰）,respectively. According to the concentrations of lake water anion and cation and p H values,we calculated the saturation coefficient index with respect to calcite（ IAP / Ksp）,and the results showed that the lake water in Lake Bosten had a necessary condition of authigenic carbonate precipitation. Judging from the spatial distribution,TIC showed much higher values in the north area than in the south area,with the highest content occurring near the Huangshui area and lowest in the south estuary and central lake section. In general,the spatial distribution of TIC in the surface sediments of Lake Bosten was mainly under the influence of inflows by Kaidu River and Huangshui River,which resulted in thespatial differences of lake water salinity and nutrients,thereby affecting the precipitation and distribution of carbonate. In addition,lake hydrodynamic conditions might also affect the preservation and distribution of inorganic carbon in local environment of the Lake Bosten,especially in the mid-west lake section. The δ^13Ccarband δ^18Ocarbvalues were significantly different in different lake environment,with the most negative values near the Kaidu River estuary and the east-deep water area