引用本文: | 李文朝,陈开宁,吴庆龙,王刚.东太湖表层沉积物的磷饱和度初步研究.湖泊科学,1998,10(3):49-54. DOI:10.18307/1998.0309 |
| Li Wenchao,Chen Kaining,Wu Qinglong,Wang Gang.A Preliminary Study on Phosphorous Saturation of the Top Sediment in East Taihu Lake. J. Lake Sci.1998,10(3):49-54. DOI:10.18307/1998.0309 |
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摘要: |
对东太湖一个横断面上8个样点、1个网围养鱼区样点、1个鱼塘样点的表层10cm沉积物含磷量进行了分层采样分析.并以表层沉积物和湖水组成系统.通过磷添加研究了沉积物的磷饱和度.结果表明,东太湘表层沉积物总磷含量已经达到了0.0465%-0.0993%,略低于鱼塘沉积物的含磷量.表层沉积物的磷蓄积量已经基本达到饱和,当湖水中PO3-4-P含量达到了200-300μg/L(是现在湖水实际含量的25-48倍),表层沉积物的总磷含量也只能增加0.037-0.077mg/g(是现在沉积物实际含量的0.06-0.14倍).网围养殖区沉积物磷含量和磷饱和度均高于非养殖区. |
关键词: 东太湖 沉积物 磷 饱和度 |
DOI:10.18307/1998.0309 |
分类号: |
基金项目:环境水化学国家重点实验室开放基金、国家自然科学基金、国家“九五”攻关项目 |
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A Preliminary Study on Phosphorous Saturation of the Top Sediment in East Taihu Lake |
Li Wenchao1, Chen Kaining1, Wu Qinglong1, Wang Gang2
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1.Nanjing Institute og Geography Limnology, Cheinese Academy of Science, Nanjing 210008;2.Department of Biology, Lanzhou University, Lanzhou 730000
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Abstract: |
In eutrophic lakes, the sediment usually plays as a large sink for phosphorous, but its capacity to take up more phosphate is quite limited. In this investigation, phosphorous saturation of the top sediment in East Taihu Lake was studied and used as an index of lake eutrophication. Eight sample points were sited along a line across the lake, and the top 10cm sediment was collected. The top sediment samples was also taken from am old fish farming pond and a pen as contracts. One series of row samples was cut into peacs of lcm and analyzed for total phosphorous (TP) and reactive phosphorous (RAP) content. It was found that the content of TP in the top sediment varies from 0. 0465% to 0. 0993%.and RAP from 3. 48 mg/kg to 19. 84 mg/kg. The fish-pond sediment had the highest TP and RAP content among all the the samples,but there was no remarkable difference between pen sediment and lake sediment.Ten experimental systems were prepared by mixing 2-kg sediment with the lake water in plastic tanks of 90L volume. The tanks were covered, aired with a pump and kept in dark. Phosphate (53mg P) was added to each system in four times to detect phosphorous saturation of the sediment. The sediment samples from fish-pond and pen were already phosphorous-satura-tred, and the lake sediment samples were nearly phosphorous-saturated. After adding 53 mg phosphate-phosphorous in each system. phosphate level of the water phase became as hign as 200-300/xg/L (25-48 times as high as in the lake water),but TP content of the sediment only increased 0. 037-0. 077 mg/g in the sediment (0. 06%-0. 14% of content). This indicates that the lake is now very sensitive to phosphorous pollution. Good care has to be taken for keeping a phosphorous balance in the lake ecosystem. |
Key words: East Taihu Lake sediment phosphorous saturation |