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31.
5种淡水浮游藻对萼花臂尾轮虫饵料效果的比较研究──藻的最适投喂密度及轮虫相应的种群增长 总被引：1，自引：0，他引：1
于1993年9月在山东省胶南市鱼苗繁殖地池塘采得萼花臂尾轮虫,采用种群累积培养法,对其摄食5种淡水浮游藻的最适密度及其相应的种群增长进行研究。结果表明,该轮虫摄食这5种藻的最适密度（×106cell／ml）分别是：蛋白核小球藻,45;斜生栅藻,25;小球衣藻,5;卵形隐藻,0．2;中型裸藻,0．1。导出了藻的细胞大小（x）和最适投喂密度（y）之间的回归方程为：y＝－15．5＋216／x（r＝0．9826,P＜0．01）。在5种藻的最适密度下比较了投喂轮虫的饵料效果,结果是,5种藻中以蛋白核小球藻和斜生栅藻为最优,其它依次为卵形隐藻、小球衣藻和中型裸藻。据此,认为蛋白核小球藻和斜生栅藻是该轮虫批量培养乃至工厂化培养的首选饵料。 相似文献
32.
不同地理区域湖泊中萼花臂尾轮虫的生活史特征 总被引：2，自引：2，他引：0
以3.0×106cells/ml的斜生栅藻(Scenedesmus obliquus)为食物,应用生命表统计学等方法比较研究了于2008年冬季采自芜湖市汀棠湖和广州市荔湾湖的萼花臂尾轮虫(Brachionus calyciflorus)在不同温度(10℃、15℃和20℃)下的生活史特征.结果显示,10℃下,芜湖种群除内禀增长率外的其他各生命表统计学参数均显著大于广州种群.15℃下,芜湖种群仅世代时间和后代混交率显著大于广州种群.20℃下,芜湖种群的世代时间和后代混交率显著大于广州种群,而总生殖率、净生殖率和内禀增长率则相反.两地理种群轮虫出生时的生命期望、世代时间和平均寿命均随温度的升高而逐渐显著地缩短,内禀增长率随温度的升高而逐渐显著地增大;但缩短或增大的速率在两地理种群间存在着差异.芜湖种群的总生殖率和净生殖率不受温度的显著影响;而广州种群的总生殖率随温度升高而逐渐显著地增大,净生殖率在20℃和15℃下无显著差异,但都显著高于10℃下.芜湖种群的后代混交率在10℃下显著高于20℃下,但均与15℃间无显著性差异;广州种群的后代混交率随温度的升高而逐渐显著地增大.两地理种群内禀增长率间的差异可能与各自对所栖息的水环境年平均温度的长期适应有关,而后代混交率间的差异则是它们对水温季节变化长期适应的结果. 相似文献
33.
Maternal eff ects are one of the most interesting topics in evolutionary ecology as they can aff ect the rate of evolution and population dynamics by phenotypic manipulation of off spring related to fi tness. At present, studies examining the interaction between maternal environment eff ects and maternal age (birth order) eff ects are scarce. We designed an experiment to reveal whether environmentally induced maternal manipulation works equally on off spring across birth orders in rotifer Brachionus calycifl orus. In the experiment, newborn amictic mothers (F0) were cultured parallelly in low (LD) and high (HD) population density. Off spring (F1) of young (YF0) and old (OF0) mothers in both LD and HD groups were cultured under a crowded condition and the mixis ratios of both F1 and F2 were examined. Results show that F1 from HD-YF0 had a signifi cantly higher mixis ratio and those amictic ones produced daughters (F2 ) with higher mixis ratio in response to crowding than those from HD-OF0. In contrast, no such diff erences among F1 siblings were found in the LD-F0 group. Therefore, the eff ect of maternal age on the sexual propensity of the off spring can be aff ected independently by the maternal population density. 相似文献
34.
UV-B辐射增强对壶状臂尾轮虫摄食的影响 总被引：4，自引：0，他引：4
研究了UV-B辐射条件下壶状臂尾轮虫(Brachionusurceus)对6株海洋微藻:小球藻(Chlorellasp.)、绿色巴夫藻(Pavlovauiridis)、扁藻(Tetraselmischuii)、球等鞭金藻8701(IsochrysisgalbanaPark8701)、牟氏角毛藻(Chaetocerosmuelleri)和小新月菱形藻(Nitzschiaclostertum)的室内摄食实验。结果表明,UV-B辐射增强对壶状臂尾轮虫的摄食有显著的抑制作用。与对照组相比,壶状臂尾轮虫对给定饵料单胞藻的滤水率和摄食率都随UV-B辐射剂量的增大而显著减小(P<0.05)。而且壶状臂尾轮虫对每一种饵料单胞藻的滤水率和摄食率是不相同的,这说明壶状臂尾轮虫对饵料单胞藻是有选择性的。 相似文献
35.
T.A. Temerova A.G. Degermendzhy A.P. Tolomeyev 《International Journal of Salt Lake Research》1999,8(3):233-244
The growth and development of Brachionus plicatilis (Müller), a rotifer and one of the most abundant zooplankton species in Lake Shira, a saline lake at low temperature in the Republic of Khakassia, was studied in cultures at different trophic conditions. Growth indices were evaluated at natural (lake) concentrations of bacteria, Chlorella vulgaris, a microalga, and Candida utilis, a yeast. The negative effect on rotifer reproduction in the algal-bacterial community by blue-green algae was demonstrated. The ratio of ontogenetic periods was shown to be in accord with species and food concentration. Base values required to calculate B. plicatilis population simulation model parameters were defined. 相似文献
36.
The toxicity of seven major HAB (harmful algal bloom) species/strains, Prorocentrum donghaiense, Phaeocystis globosa, Prorocentrum micans, Alexandrium tamarense (AT-6, non-PSP producer), Alexandrium lusitanicum, Alexandrum tamarense (ATHK) and Heterosigma akashiwo were studied against rotifer Brachionus plicatilis under laboratory conditions. The results show that P. donghaiense, P. globosa, P. micans, A. tamarense (AT-6), or A. lusitanicum could maintain the individual survival and reproduction, as well as the population increase of the rotifer, but the individual reproduction would decrease when exposed to these five algae at higher densities for nine days; H. akashiwo could decrease the individual survival and reproduction, as well as population increase of the rotifer, which is similar to that of the starvation group, indicating that starvation might be its one lethal factor except for the algal toxins; A. tamarense (ATHK) has strong lethal effect on the rotifer with 48h LC50 at 800 cells/mL. The experiment on ingestion ability indicated by gut pigment change shows that P.donghaiense, P. globosa, P. micans, A. tamarense (AT-6) and A. lusitanicum can be taken by the rotifers as food, but A. tamarense (ATHK) or H. akashiwo can be ingested by the rotifers. The results indicate that all the indexes of individual survival and reproduction, population increase, gut pigment change of the rotifers are good and convenient to be used to reflect the toxicities of HAB species. Therefore, rotifer is suggested as one of the toxicity testing organisms in detecting the toxicity of harmful algae. 相似文献
37.
UV-B辐射对2种海水轮虫的致死效应 总被引：7，自引：0，他引：7
运用生态毒理学方法研究了UV-B辐射对褶皱臂尾轮虫(Brachionusplicatilis)和壶状臂尾轮虫(Brachionusurceus)的致死效应,旨在为阐明UV-B辐射对海洋生态系统的影响和建立指示UV-B辐射的生态毒理学指标体系提供科学依据。结果表明:UV-B辐射对2种轮虫都有严重的伤害作用,且当辐射强度达一定强度阈值会对其产生急性致死作用。实验测得:UV-B辐射对2种轮虫的急性致死强度阈值为:(50±10)μW/cm2;24h,48h和96h的半致死剂量:褶皱臂尾轮虫为4.393,2.694和1.720kJ/m2;壶状臂尾轮虫为5.856,4.516和1.730kJ/m2。由此可知,本实验UV-B辐射剂量范围和观察时间内,褶皱臂尾轮虫在UV-B辐射处理后的24h和48h内对UV-B辐射的敏感性相对要大于壶状臂尾轮虫,而在UV-B辐射处理后的96h内2种轮虫对UV-B辐射的敏感性则相近。 相似文献
38.
采用实验生态学方法研究了除草剂百草枯对褶皱臂尾轮虫(Brachionus plicatilis)的摄食和种群动态的影响。结果表明,百草枯对褶皱臂尾轮虫的24hLC50为9.17mg/L,对褶皱臂尾轮虫的摄食具有明显的抑制作用。实验浓度下褶皱臂尾轮虫对小球藻的滤水率和摄食率随百草枯浓度的增加先下降后升高。百草枯对褶皱臂尾轮虫种群动态影响显著,使轮虫的胚胎发育时间、繁殖前期和繁殖后期延长,繁殖期和平均寿命缩短,产卵量和繁殖率降低。轮虫的净生殖率和世代时间均低于对照,不同百草枯浓度下轮虫能够维持一定的种群增长。 相似文献
39.
Temperature Effect on the Life History of Three Types of Brachionus calyciflorus Females 总被引：3，自引：0，他引：3
The effect of temperature on the life history characteristics of amictic females ( AF), unfertilized mictic females (UMF) and fertilized mictic females (FMF) in Brachionus calyciflorus was studied with replicated individual cultures at 20℃ ,25℃ and 30℃ , and with algae Scenedesmus obliquus for their food. There were highly significant effects of both temperature and female type, independently and interactively, on the duration of juvenile and post-reproduction periods, and the number of eggs produced by the rotifer per life cvcle. Among all the temperature-female type combinations, all the juvenile periods of FMF, and the post-reproduction periods of UMF and FMF at 20℃, were the longest, and the number of eggs produced by an UMF at 30℃ was the highest. There were highly significant effects of both temperature and female type on the duration of the reproduction period, but no clear correlation was observed between temperature and female type. The reproduction period of AF was longer than that of UMF and FMF.Only temperature influenced significantly the mean life-span of the three types of females. The duration of juvenile,reproduction and post-reproduction periods as well as the life-span of the three types of females were all reduced very significantly with rise of temperature, but the rates of reduction varied with female type. Among the three types of females, the number of eggs produced per life cycle by an UMF was the highest, and that of a FMF was the lowest. A significant relationship between the number of eggs produced per life cycle and temperature was observed only in the UMF. 相似文献
40.
STUDY ON MIXIS POTENTIAL OF ROTIFER RESTING EGGS（ BRACHIONUS PLICATILIS ） WITH DIFFERENT COLLECTION TIMES AND DIFFERENT PRESERVATION PERIODS 总被引：1，自引：0，他引：1
The present study investigated the possible changes in the mixis potential of rotifer resting eggs produced by a single stock of Brachionus plicatilis and collected and preserved annually from 1985 - 1998. Several clones derived from each batch of resting eggs were cultured under the same conditions for 21 days. The percentage of clones appearing resting eggs and the average yield of resting eggs produced from each clone were recorded and statistically analyzed to find the differences between the mixis potential of those resting egg batches. Results showed that different batches of resting eggs had different mictic levels among their descendent clones; but no regular relationship was found between the mixis potential of resting eggs and their collection times/preservation periods. Several internal and external factors that might affect the mixis potential of resting eggs were discussed. 相似文献