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不同培养条件下多刺裸腹溞的生殖和种群增长参数 总被引:2,自引:0,他引:2
于 1996年在实验室对多刺探腹溞(Mbina macrocopa)种群的增长率及相关生态学参数进行了研究.结果表明,3个温度梯度(24、28和32℃)和3个面包酵母(Saccharomyces cerevisi-ae)密度(0.25、2 5和25 x 10_6cell.mL~(-1)下,以28℃时内禀增长力(r_m)最高;28℃时,面包酵母的投喂密度为25×10_6cell.mL_(-1)时,其r_m最大.温度28℃,面包酵母密度为25×10_6cell.mL~(-1)时,该溞的繁殖前期最短,繁殖期和寿命均最长,并且怀卵量(每窝产仔数)最大.该溞的种群密度和瞬时增长率分别在接种后第7d和第3-4d达高峰.该搔批量培养时采收时间以第5d为宜. 相似文献
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镉对中华绒螯蟹肝R—细胞亚显微结构及血清谷丙转氨酶(SGPT)活力的影响 总被引:6,自引:0,他引:6
作者提出镉对中华绒螯蟹肝胰脏R—细胞亚显微结构和血清谷丙转氨酶活力影响。在亚显微结构水平上,R—细胞中,受影响变化最明显的是线粒体;线粒体体积和其内膜嵴的破坏程度与介质镉浓度成显著的正相关关系;随镉浓度的升高,细胞器减少,内质网膨胀,细胞质和线粒体基质变稀薄。SGPT活力也随镉浓度升高而显著增大,并与R—细胞亚显微结构变化程度一致。本文还就处于不同镉浓度下的标本,与生理机能相联系的R—细胞形态变化的意义、R-细胞线粒体亚显微结构变化与SGPT活力变化的关系及SGPT活性变化的特点等进行了初步探讨。 相似文献
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EFFECTS OF TEMPERATURE AND Ca^2+ ON THE LARVAL DEVELOPMENT OF THE DECAPODA CRUSTACEAN : ERIOCHEIR SINENSIS 总被引:1,自引:0,他引:1
With increasing demand in China for the mitten crab larvae, understanding its survival mechanism gets more important. This research focused on the effects of temperature and Ca^2 on the larval growth and development. Eriocheir sinensis larvae were reared in laboratory under 21 different combinations of temperature (15, 20, 25℃) and Ca^2 content (120, 130, 140, 150, 160, 170, 180mg/l) and constant salinity (20) and pH (8), The results suggested that the survival rate increases with temperature and Ca^2 content. These combinations of temperature and Ca2 content maximized survival rate inour study and it may be the optimum water environmental conditions for culturing the larvae. To predict surviving larvae number under different water environmental conditions, 21 dynamic mathematical models were developed. This for the first time observation of the zoeal Ⅵ larvae of the Changjiang River E.sinensis population showed that they occurred under stressed water environmental conditions: temperature of 15℃ and Ca^2 content of 120,130mg/l. 相似文献
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INTRODUCTIONTheimportantenvironmentalfactorsaffectinggrowthanddevelopmentofEriocheirsinensislar vaearesalinityandwatertemperature.DifferentgrowthanddevelopmentstagesofEriocheirsinensisrequiredifferenttemperatureandsalinity (IngleandAndrews,1 976) .Ca2 +conte… 相似文献
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Monthly investigatiom were made on the population of Chinese freshwater crab, Sinopotamon yangteskiense Bott, 1967 from April, 1984 to Match, 1985. The data on 4413 specimens show that the growth was affected mainly by temperature. During the April to November growth period, the crabs' major development occured from June through October. One year was required for a fine white oocyte to develop into a mature egg. The reproduction period was June-October. Females bearing eggs were taken from June-August, and crabs with young were found from July-October. The females reproduced once a year but could for more than one year. The number of eggs carried by a female varied greatly according to the size of the crab, ranging from 30 to 100 eggs. New-bom crabs become mature after 1-2 yeats. The sex ratio was approximately 1:1 in the overall population. However, the larger crabs are predominantly male. The age distribution of S. yangtsekinese was estimated from size frequency histograms. There were more adult crabs 相似文献
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透明水蚤(Daphnia(Daphnia)hyalina Leydig)、脆弱象鼻水蚤(Bosmina fatalisBurckhardt)及短尾秀体水蚤(Diephanosoma brachyurum(Li(?)ven))是淀山湖敞水区的主要优势种,该湖枝角类数量的季节变动,受制于这三个优势种,并构成了枝角类的春季高峰及秋季高峰。温度模拟试验所得到的各项参数与现场采得的标本计算测量后的参数相一致,测出透明水蚤适应15℃左右低温,脆弱象鼻水蚤及短尾秀体水蚤适应20℃左右温度。在食物量模拟试验中,仅有怀卵量(个/窝)受食物量多少的影响,如培养于30万小球藻细胞/ml中的水蚤比7.5万藻细胞/ml中的水蚤有较多的怀卵量(个/窝)。模拟试验所得的参数,皆不能作为监测水质的参数。 相似文献