【作者】 郑晓宇；

【导师】 顾詠洁；

【作者基本信息】 华东师范大学 ， 生态学， 2011， 硕士

【摘要】 淀山湖素以“鱼米之乡”闻名,并集水源地、渔业养殖、娱乐功能于一体。近几十年来,淀山湖水质不断下降,富营养化现象越来越严重,已引起了广泛关注。2009年6月至2010年6月期间,对淀山湖12个监测点共进行了16次浮游植物监测,并对浮游植物生长动力学进行了研究。了解了淀山湖在监测期间浮游植物数量及种类的变化、淀山湖水质状况、浮游植物群落结构以及叶绿素a含量与水体各环境因子之间的相关性、浮游植物的生长特征。得到研究结果如下：1.调查期间共鉴定淀山湖浮游植物8门89属285种(含变种)。其中绿藻门43属135种,硅藻18属58种,裸藻5属34种,蓝藻9属32种,隐藻4属8种,金藻4属8种,甲藻3属7种,黄藻3属3种。尖尾蓝隐藻、小球藻、链丝藻、尖针杆藻、模糊直链藻、微囊藻属、颤藻属为淀山湖常见优势种。说明淀山湖水体目前处于富营养化状态,并有向重富营养化发展的趋势。2.淀山湖浮游植物种类数与样点的空间分布有关。上游来水入水口及其附近监测点浮游植物种类数较多,季节变化特征为春季>夏季>冬季>秋季。不同月份中淀山湖浮游植物种类数及构成比例存在差异。除夏季浮游植物以蓝藻为主要组成,其他季节浮游植物均以绿藻门为主要组成。3.淀山湖浮游植物全年平均密度为2.19×107cells·L-1,各月变化范围为9.14×105～2.12×108cells.L-1,最高值出现在2009年9月中旬。各季节浮游植物密度存在差异,夏季>春季>冬季>秋季。全年各监测点浮游植物密度大小为：元荡湖<湖中部<湖东部<湖西部、湖北部<湖南部。最低值出现在元荡湖,位于湖南部的湖1浮游植物密度最高。蓝藻暴发期与非暴发期各监测点浮游植物密度大小排列有差异,水华暴发时浮游植物密度对各监测点全年浮游植物密度变化起到决定性作用。淀山湖具有-定净化功能,出水口浮游植物密度较进水口处低。4.2009年5月到2010年6月,淀山湖叶绿素a全年平均含量为13.47 mg/m3,各月平均值变化范围为0.59-38.64mg/m3。春季>夏季>冬季>秋季。全年各监测点叶绿素a含量的变化为：元荡湖<湖中部<湖东部<湖西部<湖南部<湖北部,其中最小值出现在元荡湖,最大值出现在湖7。水华大规模暴发期叶绿素a含量的平均值为23.64mg/m3,最小值出现在拦路港,最大值出现在湖1。非大规模暴发期各监测点叶绿素a含量的平均值11.85 mg/m3,最小值出现在急水港,最大值出现在湖7。5.环境因子与全年、水华期间浮游植物群落结构的相关性存在差异。PH、DO值、温度、透明度、溶解态磷、氨氮、总氮对淀山湖全年浮游植物群落结构变化的影响较大。水华期间,DO值、透明度、总磷、氨氮、总氮对浮游植物群落结构的影响较大。除DO值、透明度、总磷、总氮外,水华期间其他的环境因子对浮游植物群落结构的影响都较全年有所下降。6.以单一元素为限制底物时,满足铜绿微囊藻正常生长的氮浓度大于4.0 mg·L-1,磷浓度大于0.50mg·L-1。铜绿微囊藻最适生长的氮浓度范围为32.0～64.0 mg·L-1,磷浓度范围为1.0～1.50 mg·L-1。以磷为限制底物时的半饱和常数Ksp远远小于以氮为限制底物时的半饱和常数KsN (KsN>Ksp),说明铜绿微囊藻对磷的亲和性高于氮。7.以单一元素为限制底物时,当氮浓度大于4.0 mg·L-1,磷浓度大于0.20mg·L-1时能满足四尾栅藻的正常生长。四尾栅藻最适生长的氮浓度范围为16.0～32.0 mg·L-1,磷浓度范围为2.0-5.40 mg·L-1。以磷为限制底物时的半饱和常数Ksp远远小于以氮为限制底物时的半饱和常数KsN (KsN>Ksp),说明四尾栅藻对磷的亲和性高于氮。更多还原

【Abstract】 Lake Dianshan is famous for flowing with milk and honey, and has the water sources, fish farming, and recreation function. In recent decade, the water quality of Lake Dianshan is declining and eutrophication is more serious. That attracted wide attention. From June 2009 to June 2010, we monitored 12 monitoring points 16 times for knowing the water quality, the change of phytoplankton species composition, density variation, the correlation between phytoplankton and environmental factors, and did the dynamic studies for knowing the growth of phytoplankton. The main results as follows:1. A total of 8 phylum,89 genera,285 species of phytoplankton were identified (with varietas). That includes Chlorophyta(43 genera 135 species), Bacillariophyta(18 genera 58 species), Euglenophyta(5 genera 34 species), Cyanophyta(9 genera 32 species), Cryptophyta(4 genera 8 species),Chrysophyta(4 genera 8 species), Pyrrophyta(3 genera 7 species), Xanthophyta(3 genera 3 species).The dominated species were Chroomonas acuta, Chlorella vulgaris, Ulothrix flaccidum, Synedra acus, Melosira ambiuga Microcystis, Oscillatoria mainly. Lake Dianshan is in eutrophication currently, and has the trend to be heavy eutrophication.2. Number of phytoplankton species in Lake Dianshan had relevance with distribution of monitoring points. Area around outlet had more phytoplankton species. The season order of species from low to high was autumn, winter, summer, spring. The percentage of phytoplankton species number in different months was different. Except Cyanophyta was the main kind species in summer, the Bacillariophyta was main species in other seasons.3. The mean phytoplankton density was on average 2.19×107cells·L-1 in one year, peak in mid-September 2009. The density order of phytoplankton from low to high was autumn, winter, spring, summer. The point order of mean density from low to high was Lake Yuandang, lake central, lake east, lake west, (equal to lake north), lake south. The lowest density point was Lake Yuandang, the highest point was the No.1 point. The phytoplankton density of different points in algae-blooming period was different from non-blooming period, and decided pinots’density order. Lake Dianshan had the furifying function, the phytoplankton density in outlet was lower than inlet. 4. The mean chlorophyll-a was 13.47 mg/m3 on average from May 2009 to June 2010, and ranged from 0.59 to 38.64mg/m3. The season order of chlorophyll-a from low to high was autumn, winter, summer, spring. The change of season was obvious. The points order of chlorophyll-a from low to high was Lake Yuandang, lake central, lake east, lake west, lake south, lake north. The lowest chlorophyll-a point was Lake Yuandang, the highest point was the No.7 point. The average of chlorophyll-a was 23.64 mg/m3, in algae-blooming period, the lowest point was Port Lanlu, the highest point was NO.1 point. The average of chlorophyll-a was 11.85 mg/m3 in non-blooming period, the lowest point was Port Lanlu, the highest point was NO.7 point.5. The correlation between environmental factors and phytoplankton community in year, algae-blooming period was different. The main factors that impact the phytoplankton community in year were as followed:PH, DO, temperature, transparency, dissolved phosphorus, ammonian, TN. The main factors that impact the phytoplankton community in algae-blooming period were as followed:DO, transparency, TP, ammonian, TN. Except DO, transparency, TP, TN, the relationship between others environmental factors and phytoplankton community was declined in algae-blooming period.6. The Microystis aeruginosa grows normally when the concentrations of TN and TP are greater than 4.0 mg-L-1、0.50mg-L-1 respectively. The optimum concentration ranges of TN and TP for the growth of Microystis aeruginosa are 16.0～64.0 mg-L-1 and 1.5.0～5.40 mg-L-1 respectively. KsN is higher than Ksp, which indicates that the affinity of TP to Microystis aeruginosa is higher than TN.7. The Scenedesmus quadricauda grows normally when the concentrations of TN and TP are greater than 4.0 mg·L-1.0.20 mg-L"1 respectively. The optimum concentration ranges of TN and TP for the growth of Scenedesmus quadricauda are16,0-32.0 mg-L-1 and 2.0～5.40 mg-L-1 respectively. KsN is higher than Ksp, which indicates that the affinity of TP to Scenedesmus quadricauda is higher than TN.更多还原