摘要
水体中氮、磷含量是影响藻类生长的重要因子,来源可分为外源性和内源性,而底泥氮、磷释放是内源性氮、磷的重要组成。为了解城市浅水型湖泊中底泥氮、磷释放过程及其规律,根据淀山湖底泥状况,在湖的进水口2个采样点、湖中心1个采样点、湖的出水口1个采样点分别采集底泥,通过在室内模拟不同的温度、扰动、pH共3个环境因子,考察其对底泥氮、磷释放的影响,研究浅水型湖泊水体中底泥氮、磷释放机制。结果表明,淀山湖底泥具有明显的TP释放特性;在不同采样点不同环境因子影响下底泥TN释放通量为-55.74^-2.98 mg/(m3.d),TP释放通量为0.21~26.39 mg/(m3.d)。温度会影响底泥的氮、磷释放,且温度越高,TN、TP释放通量越大;扰动上覆水会加快底泥氮、磷的释放,扰动越大,TN、TP释放通量越大;pH增大会加快底泥氮、磷的释放。淀山湖进水口底泥受污染较严重,在湖中心的底泥磷含量也相当高,在出水口的底泥受污染较轻。
Nitrogen and phosphorus are essential factors affecting algae growth.The sources of nitrogen and phosphorus can be divided into external and internal ones.Nitrogen and phosphorus releasing from sediment is regarded as a major component of the internal source.In order to find out the releasing process and patterns of nitrogen and phosphorus from sediment of urban shallow lakes,sediment samples were collected from 4 sits of Dianshan Lake（2 at inlet,1 at the middle of lake and 1 at outlet）.The simulated experiments were conducted in laboratory to investigate the effect of pH value,temperature and perturbance conditions on nitrogen and phosphorus releasing from sediment,the releasing mechanism of nitrogen and phosphorus in shallow lakes was also studied.The results indicated that sediment in Dianshan Lake had an evident feature of phosphorus releasing,with TN releasing flux ranged-55.74——2.98 mg/（m3·d）,while TP releasing flux ranged 0.21-26.39 mg/（m3·d）.Higher temperature and pH value could accelerate the nitrogen and phosphorus releasing from sediment,their releasing flux were increased under the perturbation of overlying water.Sediment at inlet of Dianshan Lake was seriously contaminated;the centre sediment was found rather high level of phosphorus;the pollution of outlet sediment was relative slight.
出处
《环境污染与防治》
CAS
CSCD
北大核心
2011年第5期32-35,39,共5页
Environmental Pollution & Control
基金
上海市科委项目(No.08DZ1203001)
关键词
水体富营养化
城市浅水型湖泊
氮通量
磷通量
环境因子
释放规律
water eutrophication
urban shallow lake
nitrogen releasing flux
phosphorus releasing flux
environmental factors
releasing pattern
