贵州红枫湖水库富营养化和蓝藻水华分析

[目的]分析红枫湖水库的富营养化和蓝藻水华问题。[方法]通过室内外调查研究,并结合相关文献资料,对红枫湖水质、水生生态系统、底泥污染特征以及蓝藻水华发生规律进行全面分析。[结果]红枫湖全湖处于中富营养到重富营养状态,水质为Ⅴ～劣Ⅴ类;湖泊底质蓄积了大量的营养盐,是水库富营养化的重大污染源;水生生态系统退化,易形成蓝藻水华。[结论]红枫湖的污染治理迫在眉睫。     

Reproductive performance,survival and development of nauplii and copepodites,sex ratio and adult life expectancy of the harpacticoid copepod,Euterpina acutifrons,fed different microalgal diets

A series of laboratory experiments were conducted on the harpacticoid copepod, Euterpina acutifrons, to assess the influence of 10 different microalgal diets (four monoalgal and six mixed algal diets) on several parameters related to its productivity in culture. The four monoalgal diets were the Tahitian strain of Isochrysis sp. (T‐Iso), Pavlova salina (Pav), Tetraselmis chuii (Tet) and the diatom Chaetoceros muelleri (Chaet), the five binary diets were T‐Iso+Tet, Pav+Tet, T‐Iso+Pav, Tet+Chaet and Pav+Chaet, while the tri‐algal diet was T‐Iso+Tet+Pav. All diets were fed to copepods at 1500 μ gC L^?1 and in the case of binary or trialgal diets, carbon concentration was divided equally between the two or three algae offered. Among monoalgal diets, the diatom Chaet was excellent for E. acutifrons. Out of the 10 diets tested, the binary diet Tet+Chaet, which contained the diatom Chaet, was the best for naupliar production of single pair E. acutifrons (19.5±1.7 nauplii female^?1 day^?1), significantly (P<0.05) higher than all other treatments except for the Chaet treatment (P>0.05). Similarly, in the group naupliar production trial (50 adult E. acutifrons per replicate), Tet+Chaet produced a significantly higher number of nauplii (405.8±18.6 nauplii day^?1) than the other treatments (P<0.05). Tet+Chaet further supported the highest naupliar survival (82.0±2.8%) and copepodite survival (89.0±2.8%), while the mono‐algal diet Chaet produced the second highest naupliar (76.7±2.6%) and copepodite survival (83.5±2.6%). In contrast, Pav produced the lowest overall survival at the naupliar stage (30.0±2.9%), significantly lower than all other treatments (P<0.05). While development from newly hatched nauplii to copepodites was not significantly affected by diets, mean development time from nauplius to adult was significantly different among treatments. Mean development time from hatching (naupliar I stage; NI) to the adult stage was the fastest with Tet+Chaet and Chaet (6.8±0.0 days for both treatments), which was significantly faster than that of Pav, T‐Iso Pav+Tet and T‐Iso+Pav+Te treatment (P<0.05). E. acutifrons sex ratio was significantly affected by diets, and always skewed in favour of males. Feeding on Pav resulted in the lowest proportion of females (23.7±1.2%), significantly lower than for six of the other treatments (P<0.05). Adult females had longer average life expectancy than males for all treatments, and were the longest when fed Tet+Chaet (9.5±0.4 days), which was more than twice as long as the shortest lifespan recorded for the Pav treatment (4.2±0.6 days) (P<0.05). In summary, among 10 diets tested, the binary diet Tet+Chaet appeared to support the highest culture productivity of E. acutifrons while the diatom Chaet also performed well as a monoalgal diet.     

中国海洋卡盾藻赤潮生态学研究

综述了中国海洋卡盾藻赤潮的类型、成因及其调控对策。     

横山水库浮游植物群落结构季节性变化特征

分析了2010-2011年不同季节横山水库浮游植物群落结构的变化特征.结果表明,4个季节共采集到90种(属)浮游植物,蓝藻和硅藻在横山水库浮游植物季节性演替中的作用非常重要.在太湖流域首次发现拟柱胞藻(Cylindrospermopsis sp.),夏季在水库成为优势种并引起水华,密度达到1.01×108个/L.富营养化日趋严重的横山水库为拟柱胞藻水华奠定了基础.作为生态入侵种,拟柱胞藻可以产生毒素,危害生态系统和人体健康.应加强监测和流域综合管理,防止拟柱胞藻水华扩散到流域内其它大型水库.     

三峡水库支流拟多甲藻（Peridiniopsis sp.）

2009年和2010年对三峡水库支流童庄河回水区和长江干流水体理化和浮游植物进行了同步连续跟踪监测。结果表明,2010年童庄河回水区和长江干流氮磷含量较2009年有所升高,同一年份童庄河回水区和长江干流氮磷含量各有高低,但差别不大。2-3月,童庄河回水区拟多甲藻细胞密度呈逐步增加并达到高峰的变化,其优势地位可从2009年第十三位、2010年第九位逐步成为第一优势种类,并在2010年2月26日出现小范围水华。拟多甲藻水华最先出现在回水区尾端,随着时间推移,逐步向中下游发展,并形成大面积水华,在维持一段时间后消退。童庄河回水区拟多甲藻密度上游最高,从上游至下游,密度呈下降趋势。同期长江干流出现拟多甲藻的次数较少、密度较低,通常在回水区最低密度30.91%以下。分析认为,2-3月回水区更适合拟多甲藻生长,能否形成水华主要受水文因子影响。     

福建长乐海区一次东海原甲藻赤潮生消过程分析

本文通过对2010年5月2—10日发生在福建长乐海区的一次东海原甲藻赤潮进行跟踪监测,分析并探讨了该赤潮生消过程。结果表明:东海原甲藻可在光照较强的气象条件下发生赤潮;本次赤潮暴发后东海原甲藻仍能快速增长并聚集,且主要利用硝酸氮作为氮营养成分;该赤潮生物在赤潮过程中承受低磷贫瘠环境胁迫的能力较强。对监测过程中海区各环境因子主成分分析也表明,本次赤潮限制因子有:硝酸氮、亚硝酸氮、水温以及盐度等。     

大丽花三种园艺性状之间相关性的研究

在栽培时间和栽培措施相同的情况下,通过对大丽花的“植株高度”、“开花时间”、“花径大小”之间相关性的研究,得出以下结论：(1)“植株高度”与“开花时间”有明显的相关性,即大多数矮型品种开花相对较早,大多数高型品种开花相对较晚。(2)“花径大小”与“植株高度”有一定的相关性,即在高型品种中,大花所占的比例相对较多,小花所占的比例相对较少;在矮型品种中,小花所占的比例明显增多,大花所占的比例有所减少。(3)“花径大小”与“开花时间”无明显的相关性,即大、中、小花型的品种基本上是均匀地分布于早、中、晚花型的品种当中,而无明显的倾向性。     

Effects of defoliation on fruit growth,carbohydrate reserves and subsequent flowering of ‘Hayward’ kiwifruit vines

A partial defoliation study was carried out on ‘Hayward’ kiwifruit vines with the aim of evaluating effects on fruit yield, changes in concentration of carbohydrates, and return bloom. At full bloom, ‘Hayward’ kiwifruit vines trained to the pergola system were submitted to 0% (control), 50% and 75% defoliation in the 2.0 m wide central horizontal area of the canopy. This area represents the vine ‘replacement cane zone’ (RCZ), whereas the remaining external area represents the ‘fruiting zone’ (FZ). Removing 50% of the leaves resulted in a small (−9 g in the RCZ and −3.3 g in the FZ), but significant, reduction in fruit weight compared to the control vines. More severe defoliation (75%) reduced fruit weight by 13 g in the RCZ and 7 g in the FZ. The defoliation treatment reduced the concentrations of starch and total soluble carbohydrates (glucose + fructose + sucrose) in the shoots and starch in trunk bark compared to those in control vines. The treatments caused a large reduction in return bloom, expressed as number of flowers per winter bud, by about 25% and 53% in vines with 50% and 75% defoliation, respectively.     

不同砧木对黄瓜产量、果霜及抗病性的影响

以河北农业大学蔬菜育种系选育的系列砧木品系为试材,以黑籽南瓜为对照,对嫁接后黄瓜的产量、表皮果霜以及抗病性等进行了研究。结果表明:A2、B1的早期产量均显著高于黑籽南瓜,其中A2的总产量显著高于黑籽南瓜,B1则与黑籽南瓜相近;A1的早期产量和总产量与对照差异不显著;B2、B3则明显不如黑籽南瓜。不同砧木对果实表皮果霜的影响差异显著,B1在整个结瓜期均不出现霜果,A1只有少数果实有果霜。参试砧木的抗病能力差异不显著,抗枯萎能力均达到高抗水平。综合评价以A2、B1最好,A1也较优良。     

淡水水体中蓝藻水华研究进展

综述目前国内大型浅水湖泊蓝藻水华成因研究现状,分析蓝藻水华形成的一般机理,重点阐明蓝藻水华治理的关键技术研究及其重要生态和环境意义。