Objectives: To establish a diatom database by analyzing the quatity, species distribution and differences of diatom in water samples of the whole navigable sections of the Beijing-Hangzhou Grand Canal, to provide a reference for the inference of the drowning site.
Methods: Water samples were collected at 22 sites in the navigable sections of the Beijing-Hangzhou Grand Canal (Jining section to Yangzhou Section), and the diatoms at each site were qualitatively and quantitatively analyzed by using graphite digestion-scanning electron microscopy.
Results: Sampling site T (Laohuaijiang River Line, Gaoyou City, Yangzhou City, Jiangsu Province) had the highest number of diatoms, while sampling site O (Siyang County, Suqian City, Jiangsu Province) had the lowest number of diatoms, with a large gap of 68 times. At sampling site Q (Jiangpu District, Huaian city, Jiangsu Province), there were 19 species of diatoms. The sampling site O had the least diatoms, with 7 species. There were no significant differences in species evenness and species diversity at each sampling site (P>0.05). Some sampling sites have characterized diatoms, such as Caloneis at station A (Taibai Lake, Weishan County, Shandong Province), Rhoicosphenia at station B (Nanyang Town, Weishan County, Shandong Province), Amphora at station I (Taierzhuang District, Zaozhuang City, Shandong Province) and Epithemia at station J (Pizhou 310 national highway, Xuzhou City, Jiangsu Province).
Conclusions: The species richness of diatoms gradually increased from north to south. Diatom species richness and species diversity might be higher in areas with complex environments and large population flow. Climate type has a certain influence on the distribution of diatoms.
目的: 通过对京杭大运河通航段全段水域水样中硅藻数量、种类的分布和差异进行分析，建立硅藻数据库，为推断溺水地点提供参考。方法: 在京杭大运河通航段（济宁段—常州段）中选取22个采样点采集水样，采用石墨消解-扫描电子显微镜法对各采样点的硅藻进行定性和定量分析。结果: 采样点T（江苏省扬州市高邮市老淮江线）检出硅藻数量最多，采样点O（江苏省宿迁市泗阳县）检出硅藻数量最少，两者硅藻数量差距较大，达68倍。采样点Q（江苏省淮安市江浦区）硅藻藻属最多，为19种；采样点O硅藻藻属最少，为7种，各采样点在物种均匀度、物种多样性上差异无统计学意义（P>0.05）。部分采样点拥有特征藻属，如采样点A（山东省微山县太白湖景区）存在美壁藻属、采样点B（山东省微山县南阳古镇）存在弯楔藻属、采样点I（山东省枣庄市台儿庄区）存在双眉藻属、采样点J（江苏省徐州市邳州市310国道）存在窗纹藻属。结论: 硅藻物种丰富度呈由北向南逐渐增加的趋势，环境复杂、人流量大的地区硅藻种属较丰富，物种多样性较高。气候类型对于硅藻藻属分布具有一定影响。.
Keywords: Beijing-Hangzhou Grand Canal; diatom; drowning; forensic pathology; graphite digestion-scanning electron microscopy.