摘要: |
本文对河蟹幼蟹蜕壳过程及蜕壳后的特征进行了比较详细的观察,并初步探讨了蜕壳与光照、温度及生境的关系对于0.5-2g的幼蟹,蜕壳期大约需要3-6h,软壳期需要2h,薄壳期需要15h.幼蟹特别喜欢选择有草的生境作为蜕壳地点,也喜欢在池塘浅水区蜕壳,但是在2m以内水深对蜕壳成功率没有影响.蜕壳存在明显的昼夜节律,白天蜕壳的数量显著高干夜间(F(1.30)=13.4,P=0.0009),蜕壳高峰发生在上午(07:00-11:00),低谷一般发生在夜间(23:00-03:00).协方差分析(昼夜为协变量)表明:水温的昼夜变化(28-35℃)对蜕壳并没有显著的影响(F7,11=1.99,P=0.1467),在水温高达 35℃时蜕壳仍然能顺利进行,蜕壳下限温度在14℃左右。 |
关键词: 中华绒赘蟹 蜕壳 生态环境 光照强度 温度 |
DOI:10.18307/1999.0408 |
分类号: |
基金项目:国家科技攻关(96-008-02-03)中国科学院“九五”重大项目(KZ951-A1-102) |
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Ecological Observations on Molting of Juveniles of the Chinese Mitten Crab, Eriocheir sinensis |
ZHANG Tanglin, LI Zhongjie
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Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan 430072
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Abstract: |
Molting process of E. sinensis juveniles in laboratory and the habitat, illumination and temperature in relation to molting in an earthen pond were studied during July to August, 1993. In-termolt cycle of crabs is divided into five stages (Stage A, B, C, D, E). For individuals with body-weight of 0.5-2g, stage A lasted about 2h, stage B about 15h, and stage E about 3-6h. The number of cast integuments perm 2 from weed-growing bottom was significantly greater than that from weedless bottom. Experiment shows that all the crabs molted normally at water depth of less than 2.0m. Diel variations in molting every four hours were observed, indicating that massive molting occurred at 07:00-11:00. Analysis of covariance (water temperature as covariate) suggests that the number of cast integuments every four hours in daytime (07:00-19:00) was significantly higher than that at night (19:00-07:00) (F1,30=13.4, P=0.0009); the changes in diel water temperature (28-35℃) did not affect molting (F7,11= 1.99, P=0.1467). Studies also show that crabs initiate molting at water temperature of about 14℃ and molt normally until 35℃. |
Key words: Eriocheir sinensis molt habitat illumination temperature |