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1.
基于网箱控制法和模型法的长江4种淡水鱼目标强度研究   总被引:1,自引:1,他引:0  
目标强度(target strength,TS)是将回波积分值转换成绝对资源量的关键参数,同时也是渔业声学技术的热点研究内容。2012年12月及2013年6―7月,在三峡水库中华鲟基地网箱内使用BioSonics DT-X(199 kHz)分裂波式科学回声仪测定了4种共计31尾不同鳔室构造和体型的长江淡水鱼类背腹方向的目标强度,并将此结果与基尔霍夫近似模型法测定结果进行比较。实验鱼包括鳊(Parabramis pekinensis) 6尾、鲢(Hypophthalmichthys molitrix) 8尾、鲇(Silurus asotus)10尾及长江鲟(Acipenser dabryanus)7尾。结果表明,模型法测定结果与网箱控制法所测结果无显著性差异。构建4种鱼TS值(dB)与体长(BL, cm)的标准方程分别为鳊:TS=20lg(BL)-70.1 (R~2=0.94);鲢:TS=20lg(BL)-67.0 (R~2=0.80);鲇:TS=20lg(BL)-74.5 (R~2=0.80)及长江鲟:TS=20lg(BL)-66.1 (R~2=0.94)。模型法获得实验鱼目标强度的分布表明,鱼类不同的形态学特征及鳔室数量会影响目标强度的大小与分布特征。低频(38 kHz)下鳊、鲇及长江鲟目标强度最大值对应的姿态倾角出现在-10°~0°,而鲢目标强度最大值出现在-20°~-10°,且不同种类鱼的目标强度最大值所对应姿态倾角的位置各不相同。本研究通过网箱控制法和模型法测定了4种不同鳔室构造和体型的长江淡水鱼类目标强度,可为长江淡水鱼类目标强度研究提供有益借鉴,为采用渔业声学方法进行长江淡水鱼类垂直原位监测评估资源量提供相关参数。  相似文献   

2.
本试验比较分析了2种黄颡鱼高产无公害养殖模式下所取得的产量与经济效益。结果显示,每hm2投放4~5cm黄颡鱼种苗82 500尾,采用主养黄颡鱼、套养主要大宗淡水鱼类(草鱼、鳙鱼、鲢鱼和鲫鱼)的混养池塘生产的总商品鱼每hm2的产量比单养池高出26.1%,其中每hm2比单养池多产出大宗淡水鱼3 105kg,而两种模式中每hm2黄颡鱼产量相当,均在7 500kg/hm2以上;在养殖效益方面,单养池的平均利润为71 550元/hm2,混养池的平均利润为91 770元/hm2,混养池比单养池平均高出20 220元/hm2。因此,主养黄颡鱼、套养主要大宗淡水鱼类(草鱼、鳙鱼、鲢鱼和鲫鱼)的混养模式值得广泛推广。  相似文献   

3.
蓝鳃太阳鱼(Lepomismacrochirus)(以下简称太阳鱼)为鲈形目,太阳鱼科的淡水鱼类.原产于北美洲淡水水域,鱼体高,侧偏,头小,尾小,鳃盖后缘一深蓝紫色形似耳状的突丐,体侧有7-10条暗黄色的彩条纹.一般个体成熟时体重200g左右,个别可达到lkg.  相似文献   

4.
鳍和鳔对鱼类游泳行为的影响   总被引:1,自引:0,他引:1  
比较了鲫鱼各鳍条分别剪掉后与正常鱼的行为差异及鲫鱼前鳔室被破坏后鲫鱼行为能力的改变。讨论了各鳍条对鱼类游泳的作用、不同鱼类鳍条之间作用影响的差别及鱼类对失去鳍条和鳔后的适应能力。  相似文献   

5.
以黄、渤海、东海主要养殖鱼类许氏平鲉和大黄鱼为研究对象,在消声水池中选用KF-668双屏彩色探渔仪等仪器,在50、200 kHz工作频率下对研究对象目标强度及背向反射声截面与体重和体长的关系进行研究.试验结果显示,体重和体长均可用做定量表述上述两种鱼类目标强度的参数.TS大黄鱼在50kHz频率下身体各向目标强度值介于-32.85~-58.01dB;200kHz频率下身体各向目标强度介于-29.3~-56.99 dB.TS许氏平鲉在50 kHz频率下身体各向目标强度值介于-31.74~-75.87 dB;200kHz频率下身体各向目标强度介于-31.74~-74.75 dB.大黄鱼和许氏平鲉身体各向目标强度大小为TS侧向>TS背向>TS头向>TS尾向.50 kHz:TS大黄鱼=24.8 1og L(cm)-73.9(侧向);200 kHz:TS大黄鱼=23.9 1og L(cm)-71.3(侧向).50 kHz:TS许氏平鲉=25.7 1og L(cm)-69.16(侧向);200 kHz:TS许氏平鲉=26.4 1og L(cm)-70.8(侧向).试验结果为声学水下监测仪器的设计提供数据支持.  相似文献   

6.
全双工射频识别系统(RFID)相较于半双工具有操作简便、数据传输方便等优势,国外广泛应用于鱼道过鱼效果评价。针对而国内相关研究较少的现状,以植有PIT标签的仿野生齐口裂腹鱼(Schizothorax prenanti)识别与否作为评判系统监测效率高低的依据,定量分析鱼体入射角度、鱼体入射范围、鱼体长大小和游泳速度对全双工射频识别系统监测效率的影响,以接收到监测数据作为因变量,构建Logistic回归模型,利用AIC模型准则筛选出最优的Logistic回归模型。结果表明,游泳速度(P=0.001)和鱼体长大小(P=0.03)与系统成功监测概率呈负相关。鱼体入射角度(0°~90°)对系统监测效率的影响不显著(P0.05);鱼体入射范围0~10 cm的监测效率显著高于入射20~30 cm和30~40 cm(P0.05)。为进一步提高鱼道监测效率,建议在开展实际鱼道工程监测前,应掌握鱼类基础参数(如体长)和行为(如游泳速度)数据,合理布置天线位置,将有助于为监测评估后的鱼道优化设计提供技术支撑和数据参考。  相似文献   

7.
为研究杂交黄颡鱼"黄优1号"(Pelteobagrus vachelli♂×P.fulvidraco♀)主要形态指标和雌雄个体的形态差异,对509尾杂交黄颡鱼11项计量性状(体长、全长、头长、体高、尾柄高、尾柄长、体厚、吻长、眼径、眼间距和体质量)及11项标准化性状(肥满度、体长/头长、眼径/吻长、体长/体高、体长/体厚、体长/尾柄长、头长/吻长、头长/眼径、体高/体厚、尾柄长/尾柄高和体长/全长)进行主成分分析和逐步判别分析并建立雌雄判别方程式。主成分分析显示,杂交黄颡鱼的主要形态指标可以分为整体框架轮廓指标、肥瘦程度、眼间距特征、头部特征、尾部特征和身体前部T型结构特征6个方面,累积贡献率达76.36%。散点图结果显示,雌雄个体在体质量上存在明显差异,与判别分析结果一致。通过逐步判别分析将326尾2龄杂交黄颡鱼和183尾3龄杂交黄颡鱼的11项计量性状与11项标准化性状逐步剔除,筛选出关于2龄鱼群体的全长、体长、体高、体质量、体长/体高、头长/眼径、体高/体厚和体长/全长8个变量,3龄鱼群体的全长和体质量2个变量,分别建立起性别判别函数。通过将数据代回方程中检验可得出2龄鱼综合正确率87.0%、3龄鱼综合正确率84.2%。t-检验结果显示,雌雄杂交黄颡鱼的主要差异集中在肥满度及外部轮廓指标上,雄鱼较雌鱼体型更宽、更长。上述差异性状和雌雄判别方程式可为杂交黄颡鱼性别的鉴定提供参考方法和理论依据。  相似文献   

8.
地图鱼,别名黑猪鱼、星丽鱼,属丽鱼科星背丽鱼属鱼类。产地:圭亚那、委内瑞拉、巴西。 1形态特征 地图鱼体呈椭圆形,侧扁,尾鳍呈扇形,体长可达 30 cm。地图鱼体呈黑褐色,体侧有不规则的橙黄色斑块和红色条纹,形似地图,故称其为地图鱼;因其颜色暗黑,又称其为黑猪鱼;在其尾柄基部有一黑色镶金边的圆形斑块,形似闪亮的星星,故又称其为星丽鱼。 2生活习性 地图鱼对水质要求不严格。在 20℃以上的水温中,它们能很好地生长,是比较容易饲养的鱼类。地图鱼个体较大,性情凶猛,它们不仅吃普通的鲜活饵料,而且能吃小鱼、小虾、小…  相似文献   

9.
在2013年1—12月渔业资源调查数据的基础上,研究了流沙湾海域勒氏枝鳔石首鱼的体长分布、体长-体质量的关系、肥满度月变化、饵料组成、摄食强度和营养级等生物学特性。结果表明:流沙湾海域枝鳔石首鱼体长82~145 mm,优势体长组为116~125 mm和106~115 mm;体长(L)-体质量(W)关系方程为:W=0.0242L~(2.9564)(R~2=0.9471);肥满度最大值出现在2月份,最小值出现在7月;枝鳔石首鱼的饵料组成以甲壳类为主要类群。枝鳔石首鱼的空胃率随季节变化显著(P0.05),在冬季最大,春季达到最小,饱满度指数在秋季最高,冬季最低;营养级变化范围在2.69~3.11,平均营养级为2.94。  相似文献   

10.
<正>黄颡,俗名黄骨、汪丁,是我国优质名贵淡水鱼类,广泛分布在我各大水域,其中以两广、两湖、浙江、四川等地为主产地。黄颡具有生长周期短、群体产量高、鱼价稳定利润可靠,耐运输、上市规格及出塘时间灵活等特点,同时,两湖两江黄颡消费量增大,促进了黄颡人工养殖规模的日益扩大,其养殖范围也从主养区向周边地区扩散,由主养省份向临近省份扩散。目前浙江主养区域在湖州。黄颡鱼属有5个种类,分为黄颡鱼、瓦氏(江)黄颡鱼、光泽黄颡鱼、中间黄颡鱼、长须(岔尾)黄颡鱼。由于浙江黄颡育苗技术及设备落后,浙江区域内人工养殖黄颡  相似文献   

11.
流速是影响鱼类生存与繁衍栖息的重要因子。为了了解鱼类在中等流速区的游泳行为,探究其对水流的适应特征,利用鱼类游泳能力测定装置,以鲢(Hypophthalmichthys molitrix)幼鱼[体重(9.82±3.81) g,体长(8.56±1.11) cm)]为对象,采用递增流速法,分析了游泳过程中的非疲劳贴网行为与姿态转换行为。结果表明,在22℃水温条件下,鲢幼鱼平均相对临界游泳速度(critical swimming speed,U_(crit))相比其体长(body length,BL)为(6.00±0.93)BL/s;其非疲劳贴网速度(no-fatigue impingement speed,U_(imp))与临界游泳速度呈线性正相关,U_(crit)=1.03 U_(imp)+1.26 (R~2=0.86,P0.01);姿态转换速度(gait transition speed,U_(tran))与临界游泳速度呈线性正相关,U_(tran)=0.59 U_(crit)+1.55 (R~2=0.43,P0.01);非疲劳贴网速度与姿态转换速度呈线性正相关,U_(tran)=0.51U_(imp)+2.72 (R~2=0.41,P0.001)。在中等流速范围内(2~4 BL/s),实验鱼摆尾频率(tail beat frequency, TBF)和单次摆尾周期前进距离(stride length, SL)均随流速增加而增大。首次出现非疲劳贴网的流速为4.62 BL/s,流速增至5.08 BL/s时出现姿态转换行为。发生姿态转换后,TBF开始下降,而SL随流速增加快速增大。研究显示,鲢幼鱼非疲劳贴网行为对游泳能力和姿态转换速度有显著影响,且非疲劳贴网行为与姿态转换行为之间也存在相互影响。研究结果可为自然环境中鱼类生态行为研究、鱼类资源保护及渔业管理提供参考。  相似文献   

12.
To provide target strength (TS) information for estimating the body length of yellowfin tuna Thunnus albacares and its abundance around fish aggregating devices, TS was measured ex situ and in situ. In the ex situ TS measurements, two cameras synchronized with a 200 kHz echosounder were used to obtain the precise orientation of the yellowfin tuna under free swimming conditions. The ex situ TS (dB re 1 m2)–fork length (FL, cm) regression was: TS = 27.06 log (FL) − 85.04. Ex situ TS was found to reach its maximum in the tilt angle range of −15° to −20° after excluding TS samples with insignificant correlation to the tilt angle. The angle between the vertebra and the swim bladder was approximately 25° according to X-ray images, supporting the above tilt range. The relationship between the swim bladder volume (V SB, ml) and the fork length was: V SB = 0.000213 FL3. The results from the in situ TS measurements indicated that the tilt angle was highly concentrated between −10° and 15°. The results from a calculation using the ex situ TS–FL equation with the fork length from biological sampling agreed strongly with the average in situ TS.  相似文献   

13.
可靠的能量消耗估算可以更好地衡量鱼体在上溯过程中的能量分配方式,为鱼道水力设计提供依据,实现鱼道过鱼的高通过率。为探究鲢(Hypophthalmichthys molitrix)幼鱼运动过程中游泳行为和能量消耗的关系,利用丹麦Loligo Systems公司生产的鱼类行为视频跟踪系统,对24尾鲢幼鱼进行了室内游泳行为实验。采用流速递增法测得鲢幼鱼的活动代谢率,水体溶氧量由每个流速工况下等时距读取,静水条件下通过AutoRespTM测定水体溶氧变化值,计算标准代谢率;利用水槽上方架设的摄像头(25帧/s)记录鱼体运动行为,连接uEye Cockpit程序观测鱼体运动情况,采用LoliTrack进行运动行为分析,获取鱼体运动行为学参数。结果表明,鲢幼鱼的游泳速度与摆尾频率(TBF)呈显著正相关关系,其耗氧率(MO2)与摆尾频率(TBF)的拟合方程为MO2=318.3+1.04TBF2.87(R2=0.99,P0.001),拟合指数值为2.87,且摆尾频率的幂指数越大,表征鱼体游泳效率越低。实验测得鲢幼鱼的标准代谢率(SMR)为(284.47±30.75)mg/(kg·h),耗氧率方程得到的标准代谢率拟合值为318.3mg/(kg·h),与实测值较为接近;通过建立活动代谢率(AMR)与鱼体重量(M)及游速(U)的关系,得出鲢幼鱼生物能量模型AMR=10.39 M0.12 U0.39(R2=0.95,P0.001)。生物能量模型的建立,可以为鱼道不同过鱼目标的水力设计提供参考。  相似文献   

14.
测定和研究了闽-粤东族官井洋种群养殖大黄鱼群体的形态特征与生长类型,并与文献报道的其亲本野生大黄鱼群体的形态特征进行了比较。结果表明:养殖大黄鱼的眼径/头长和体高/体长的比值普遍大于野生大黄鱼,而吻长/头长和眼后头长/头长的比值普遍小于野生大黄鱼。同时,养殖大黄鱼群体的眼径/头长、吻长/头长和头长/体长三项比值具有随着鱼体体长的增长而逐渐减小的特点。养殖大黄鱼体长与体重、体长生长与养殖时间的关系分别为:W=0.0195L2.9775(R2=0.9959)、y=-0.0259x2+1.7125x+4.1534(R2=0.989),鳔重与体重的比值为0.61%~2.26%,月平均鳔重指数1.08%~1.85%。  相似文献   

15.
In a test involving 5 inbred strains, and 9 strain crossbreds of the common carp, one inbred strain was found to be infected by Epidermal epithelioma disease and a second inbred strain was infected by a swim bladder inflammation. Crossbreds between these 2 strains, as well as between them and other strains did not show a single fish infected by either disease. It was concluded that susceptibility to both of these diseases is controlled by recessive genetic factors. It appears that the decreased incidence of Epidermal epithelioma in Israeli fish ponds in recent years has been due to the increased use of selected crossbred carp fry. The incidence of Epidermal epithelioma was twice as high in experimental ponds with a high stocking rate than in those with a lower stocking rate.The swim bladder inflammation was apparently due to a blockage of the pneumatic duct, with secondary infection by Aeromonas liquefaciens.  相似文献   

16.
Integrated aquaculture has been widely used for pearl production in the freshwater pearl mussel Hyriopsis cumingii farming in China, but the production technology has not reached the state of the art. This study explored the optimal stocking ratio of fish to mussel (fish–mussel) through a 90-day experiment conducted in land-based enclosures. The integrated system included pearl mussel, grass carp, gibel carp, silver carp and bighead carp, with four fish–mussel stocking ratios by number: 1:1 (R1), 2:1 (R2), 3:1 (R3) and 4:1 (R4). The pearl yield was higher in the R2 enclosures than in the R1 and R4 enclosures, whereas the fish yield was higher in the R3 and R4 enclosures than in the R1 and R2 enclosures. The phosphorus (P) utilization efficiency was higher in the R2, R3 and R4 enclosures than in the R1 enclosures. The wastes of nitrogen (N) and P enhanced with the increase of fish–mussel ratio. Regression analyses indicated that the fish–mussel ratio was 2.3:1 for the maximal pearl yield, and 3.6:1 for the maximal fish yield, and 1.6–2.3:1 for the minimal N waste, and 1.9–2.9:1 for the minimal P waste. This study indicated that the suitable fish–mussel stocking ratio was 2:1 in the integrated culture of H. cumingii, grass carp, gibel carp, silver carp and bighead carp.  相似文献   

17.
Early‐stage mortality due to surface water tension‐related death and due to sinking to the tank bottom was investigated for yellowfin tuna, Thunnus albacares (YFT), larvae. Different aeration rates and rearing water surface conditions were examined to evaluate the effect on larval survival, swim bladder inflation and growth. The percentage survival of yolk sac larvae was significantly higher when the rearing water surface was covered with fish oil at aeration rates of 0 and 50 mL min?1. The highest mortality occurred at the highest aeration rate of 250 mL min?1 regardless of surface water condition. A second experiment was conducted twice under different water surface conditions: the water surface was covered by fish oil (FO), skimmed of fish oil (SS), and was not treated (NC). The percentage survival was not significantly different between treatments after 7 days of feeding. In contrast to the survival, the proportion of larvae with inflated swim bladders was significantly higher for the NC and SS groups than that of the FO group. Results of these experiments indicate that the addition of oil to the rearing water surface without its removal interferes with the initial swim bladder inflation in YFT larvae. These results also indicate that YFT larvae need to obtain (gulp) air at the water surface for initial swim bladder inflation, and success of initial swim bladder inflation may be crucial for their survival.  相似文献   

18.
Bovine lactoferrin (LF) was evaluated for its ability to suppress stress reactions in carp, Cyprinus carpio L., held under deteriorating environmental conditions. Three test diets containing different levels of LF (0.01, 0.1 and 1%) were fed at 2% of fish body weight per day, i.e. LF at 2, 20 and 200 mg kg(-1) body weight day(-1) was administered orally to carp for 14 days at 20 °C. In the fish reared at a density of 2 individuals 10 l(-1) , plasma cortisol, adrenaline and noradrenaline decreased in the groups fed with 0.1 and 1% LF content diets. In the fish held at a density of 10 individuals 10 l(-1) for 3 days, plasma cortisol, adrenaline, noradrenaline, dopamine and glucose were higher than those at 2 individuals 10 l(-1) in both the control and LF-treated groups. The extent to which these parameters were elevated in the fish held at the same density was reduced with increasing LF content of the diet. Twenty-four hours after exposure to hypoxic conditions (dissolved oxygen level, 2.5 mg l(-1) ), haemoglobin, haematocrit, plasma cortisol, adrenaline, noradrenaline and dopamine increased significantly in all groups. The responses of hypoxic fish fed with 0.1 and 1% LF diets for 14 days were smaller than those of the controls. These results suggest that LF has an ability to reduce the stress response of carp held under deteriorating environmental conditions.  相似文献   

19.
以鳞片作为年龄鉴定材料,研究转基因鲤(Cyprinus carpio)放流试验的人工湖中鲫(Carassius auratus)的年龄组成、大小与生长特性。结果显示:鲫种群由4个年龄组(1 a~4 a)构成。体重(W,g)与体长(L,mm)的关系式为:W=2.597×10-5L3.0133;体长与鳞径(R,mm)的关系式为:L=7.4+29.8R。生长模式可用von Bertalan-ffy生长方程描述:Lt=28.8[1-e-0.254(t+0.307)],Wt=668.9[1-e-0.254(t+0.307)]3.0133,体重生长拐点年龄ti=4.04 a。还对转基因鲤放流人工湖泊中鲫的生长数据同其它湖泊中的作了比较。这些数据为今后探讨转基因鲤种群的建立对鲫生长的影响积累了背景资料。  相似文献   

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