| 引用本文: | 章婷曦,文莹亭,董丹萍,王国祥.太湖西北部表层沉积物粒度特征与沉积环境.湖泊科学,2018,30(3):836-846. DOI:10.18307/2018.0325 |
| ZHANG Tingxi,WEN Yingting,DONG Danping,WANG Guoxiang.Grain size features and sedimentary environment of surficial sediments in the northwest Lake Taihu. J. Lake Sci.2018,30(3):836-846. DOI:10.18307/2018.0325 |
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| 摘要: |
| 对太湖西北部主要入湖河流、河口及近岸湖区64个表层沉积物样品进行粒度分析，结合粒度参数计算和聚类分析，探讨了表层沉积物的粒度分布特征及其沉积类型.研究结果表明：研究区沉积物平均粒径介于4.0~58.7 μm之间，粒级组分为黏土、粉砂和砂，其含量的均值分别为7.19%、81.81%和11.00%.太湖西北部表层沉积物以粉砂和砂质粉砂为主；研究区粒度总体呈南粗北细的分布特征，太湖西部沿岸区距离物源区较近且水动力条件复杂，沉积物粒度较粗.太湖北部入湖河流沉积物的频率曲线峰形较宽，峰值位于细粒级；西岸入湖河道多呈单峰态，粒径偏粗；河口区沉积物粒径较河道偏粗，粗颗粒含量高.Q型聚类分析结果表明，研究区可分为4类沉积区，其中3类沉积区有典型特征：第1类沉积区主要分布在太湖西部沿岸，其沉积物粒度相对较粗；第2类沉积区主要位于入湖河流河口，沉积物粒度最粗；第3类沉积区位于蓝藻频发的梁溪河，其沉积物黏土含量极高，表明沉积物粒度特征可能与污染状况有一定的联系. |
| 关键词: 太湖西北部 表层沉积物 粒度 空间分布 沉积环境 |
| DOI：10.18307/2018.0325 |
| 分类号: |
| 基金项目:国家自然科学基金项目（41303058）、江苏省太湖水污染治理专项（TH2014402）和江苏高校优势学科建设项目联合资助. |
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| Grain size features and sedimentary environment of surficial sediments in the northwest Lake Taihu |
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ZHANG Tingxi1,2,3, WEN Yingting1, DONG Danping1, WANG Guoxiang1
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1.School of Environment, Nanjing Normal University, Nanjing 210023, P. R. China;2.Jiangsu Center for Collaborative Innovation in Geographical Information Resource Development and Application, Nanjing 210023, P. R. China;3.Jiangsu Key Laboratory of Material Cycle & Pollution Control, Nanjing 210023, P. R. China
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| Abstract: |
| Sixty-four surficial sediment samples taken along the northwest of Lake Taihu were analyzed by particle size analysis. Combined with particle size parameter calculation and cluster analysis, the characteristic of particle size distribution and the sedimentary types of surficial sediments were discussed. The results show that the sediments had average particle sizes of 4.0-58.7 μm, and average grain mass fractions of 7.19% for clay, 81.81% for silt, and 11.00% for sand, respectively. Silt and sand are the dominant components in the sediments. There are more coarse particles in the western coastal area and more fine particles in the northern lake. The west bank of the study area was characterized by the enrichment of coarser deposition, indicating strong hydrodynamic conditions and nearby source. The frequency curves of sediments in the northern part of Lake Taihu are wide with the peak in the fine grain level, while that of the sediments in the western area are single-peaked and the grain size was coarse; the grain size of sediments in the estuary was coarser than that of river channel. The results of Q-type cluster analysis show that the study area can be divided into four types of sedimentary areas, among which three types of areas are typical. The first type of sedimentary area is located in the west bank of Lake Taihu with relatively coarse grain size. The second type sedimentary area is in the estuary with the coarsest particles. the third type of sedimentary area is located in the Liangxi River where cyanobacteria bloom occurs frequently, and its clay content was extremely high, indicating that the grain size of the sediments may be related to the lake pollution condition. |
| Key words: Northwest Lake Taihu surface sediments particle size spatial distribution sedimentary environment |
