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1.
在水温20 ℃和盐度30的条件下研究摄食水平对(魚夋)碳收支的影响.摄食水平分为饥饿(不投喂)、1、2、3、4(指日摄食量占鱼体重百分比)和自由摄食共6组,实验持续21 d.结果表明:摄食水平对碳消化率没有影响.碳转化率、净生长率与摄食水平之间呈显著正相关关系,在自由摄食状态下分别达到9.29%和10.41%.非粪便流失碳随摄食水平增加而显著降低.粪便碳占摄入碳比例变化不大,与摄食水平间无规律性关系.在自由摄食状态下,大部分摄入碳量均通过非粪便途径流失,其中大部分是呼吸过程消耗的.余下的部分中,粪便流失量和鱼体保存量各占一半.鱼体每增长1 g体重伴有979.56 mg碳流失.在自由摄食状态下(魚夋)碳收支方程式为:100摄入碳＝9.29生长碳+9.69粪便碳+79.94非粪便流失碳. 相似文献
2.
Effects of diet and body size on phosphorus utilization of Liza haematocheila T. ＆ S. 总被引：1，自引：0，他引：1
A 21-d laboratory experiment was conducted to study, the phosphorus （P） utilization of two different diets by redlip mullet Liza haematocheila T. ＆ S. Sand-filtered water in salinity 30 and temperatare 25℃ was used. Twenty-nine fish individuals were divided into three groups： 11 to group 1 （G1） fed on diet 1, 11 to group 2 （G2） fed on diet 2, and 7 to contrast group. Diet 1 was a commercial feed, more valuable in nutrition than diet 2 that similar to natural detritus. The results show the intake phosphorus （IP） of G1 was significantly higher than that of G2, and both increased linearly with body size at a certain amount of diet. The retention phosphorus （RP） in fish of G1 was lower than G2. The relationship between retention phosphorus and body size was positive and stronger in G2. Significant difference in faecal phosphorus （FP） was found between G1 and G2. Body size significantly impacted the excretion phosphorus （EP） in G1 but G2. The loss of intake phosphorus in G1 was 10.83-20.27 mg per g fish weight gain, higher than that in G2 for 6.63-9.56. Of the phosphorus, about 10% was allocated into growth, 50% in faeces, and the rest lost in excretion. The main part of phosphorus was lost in faeces but excretion. The phosphorus budget of the fish could be described as 100IP = 7.40RP ＋ 47.39FP ＋ 36.63EP （Diet 1） or 100IP = 11.93RP ＋ 56.64FP ＋ 21.76EP （Diet 2）. 相似文献
3.
通过形态学比较研究和饲养生态学的观察,作者补充了细刺鱼牙齿结构特征和条石鲷的体色、鳍色的形态学特点,探讨了这两种鱼类的生态习性和１９９８ 年在青岛海域出现的原因。进行２～３ 个月的饲养实验后,得到细刺鱼月均增长量为１０．３％ ,条石鲷为１４．６％ 而明显高于同池饲养六线鱼的结果。鉴于两种鱼类彩色艳丽、游姿优美,具观赏价值,为此建议可将这两种鱼作为海水养殖或观赏鱼类的实验对象 相似文献
4.
鲻鱼(Mngil cephalus Linnaeus)隶属于鲻形目,鲻亚目,鲻科,鲻属,俗称马友、九棍、葵龙、田鱼、马头等。其鱼苗资源丰富,是我国南方主要的养殖对象。鲻鱼肉细嫩,味鲜美,肉甘平,对消化不良、小儿疳积、贫血有一定辅助疗效。迄今为止,未见有关鲻鱼成分分析和营养价值的报道。笔者对鲻鱼的肌肉蛋白质的营养价值进行了分析与评价,为其营养学研究提供理论数据,为其进一步养殖推广、加工及综合利用打下基础。 相似文献
5.
大泷六线鱼的营养成分分析 总被引：9，自引：0，他引：9
大泷六线鱼（Ｈｅｘａｇｒａｍｍｏｓ ｏｔａｋｉｉ）俗称黄鱼,隶属鱼由形目,六线鱼亚目,六线鱼科,六线鱼属,具有耐低温、肉质鲜美等特点,颇受消费者青睐。近年来,由于大量捕钓以及大泷六线鱼本身产卵量少等原因导致其天然资源日渐匮乏,人工养殖业应运兴起。但迄今为止,有关大泷六线鱼的基础生物学研究较少,至于营养化学更未见报道。本实验通过对大泷六线鱼营养成分的测定分析,同时比较测定鳚鱼、杜父鱼的营养成分,并对照其他几种常见的养殖鱼类,初步评定其营养价值,为其营养学研究提供基础性资料并期进一步推广发展其养殖事… 相似文献
6.
Index systems on river health assessment are difficult for using in practice, due to the more complex and professional indicators adopted. In the paper, some key indicators which can be applied for river health assessment in general were selected, based on the analysis of 45 assessment index systems with 902 variables within around 150 published papers and documents in 1972-2010. According to the fields covered by the variables, they were divided into four groups: habitat condition, water environment, biotic status and water utilization. The adopted number and the accepted degrees in the above systems of each indicator were calculated after the variables were combined into the indicators, some of the widely accepted indicators which can reflect different aspects of river condition were selected as key indicators in candidate. Under the correlation analysis amongst the key indicators in candidate, 8 indicators were finally suggested as the key indicators for assessing river health, which were: coverage rate of riparian vegetation, reserved rate of wetland, river continuity, the changing rate of water flow, the ratio of reaching water quality standard, fish index of biotic integrity, the ratio of water utilization and land use. 相似文献
7.
The Mekong supports one of the richest inland fisheries in the world, with many of the fish migrating long distance to spawn.
Little is known about the fisheries and migration strategies of the Upper Mekong whilst it is supposed that many fish species
move between the Lower and Upper Mekong. Most likely, natural fish migration in the river has been altered by dam construction
across the mainstream of the Upper Mekong. In this paper, the interconnectivity of fish species between different sections
of the Mekong and negative impacts of dams on migratory fish are studied. Of the 162 fish species in the Upper Mekong and
the 869 species in the Lower Mekong, 61 species are common. Results show that there is no significant difference at order
level between the UM and LM. Similarity coefficients are used to evaluate interconnectivity at species, genus and family levels
among four different sections of the Upper Mekong with each other and with the Lower Mekong as a whole. The highest similarity
is found between the middle and lower reach of the Upper Mekong at species and genus levels and the middle and upper reach
at family level. Of the eight cascade dams, Mengsong Dam in planning is considered as the biggest threat to migratory fish
from the Lower Mekong and should be particularly concerned.
Supported by National Natural Science Foundation of China (No. 40601096) 相似文献
8.
9.
【目的】调查闽江口龙头鱼资源,估算其生物学参数。【方法】于2015年1月、5月、8月、11月在福建闽江口11个采样点(25.85°―26.29°N,119.65°―119.87°E)采集龙头鱼3 770尾,测量其体长、体质量,用Fi SATⅡ软件中的ELEFAN I方法,估算龙头鱼的生长、死亡参数及其开捕体长和单位补充量渔获量。【结果】闽江口渔场龙头鱼体长(L)体质量(m)关系为:m=0.000 7 L~(3.804 2) (R~2=0.961 1);龙头鱼Von Bertalanffy生长方程估算的生长参数K、L_∞、m_∞、t_0分别为0.52、28.7 cm、246.1 g和-0.317龄;由生长方程推算出龙头鱼的拐点年龄约为2.252龄,拐点体长约为21.2 cm,拐点体质量约为77.1 g;根据长度变换渔获曲线法估算龙头鱼的总死亡系数为1.67,由Pauly经验公式估算自然死亡系数为1.04,捕捞死亡系数为0.63,开发率为0.377;由动态综合模型估算出龙头鱼的开捕年龄为0.712龄,对应开捕体长为11.9 cm。【结论】闽江口龙头鱼资源处未过度开发状态。 相似文献
10.
山东半岛东端以岩基海岸为主,而浅海多为岩礁底质,适宜大型藻类生长。为探究该海域的大型藻类群落结构特征,于2018年11月(秋)、2019年2月(冬)、5月(春)和8月(夏)对山东荣成马山里海域的三个典型生境(草床区、天然礁区和泥沙区)中的大型藻类进行了调查。结果显示：三种生境共鉴定出大型藻类23种,其中红藻门15属15种,褐藻门3属4种,绿藻门3属4种。物种数最高值出现在天然礁区(22种),最低值出现在泥沙区(12种)。生物量最高值为春季草床区(1567.44±21.29)g.m-2、最低值为秋季的泥沙区(594.45±107.06)g.m-2。大型藻类优势种在不同生境、不同季节不同：草床生境为小珊瑚藻,在四个季节中均占绝对优势;礁区为绿藻向红藻、褐藻变化;泥沙区为从红藻到褐藻变化。Pielow均匀度指数的最高值在三个生境中相近且均出现在冬季;多样性指数最高值、最低值分别出现在礁区与泥沙区;Margalef丰富度指数的最高值出现在秋季的礁区,而最低值出现在夏季的泥沙区;聚类与排序结果表明,大型藻类群落结构在不同生境不同季节差异都显著。结果表明,生境特征和季节性变化是影响底栖大型海藻群落结构的主要因素。 相似文献