Fish utilisation of managed realignments   总被引：3，自引：0，他引：3  

S. COLCLOUGH  L. FONSECA  T. ASTLEY  K. THOMAS  & W. WATTS 《Fisheries Management and Ecology》2005,12(6):351-360

Abstract  One area of ecological benefit not yet fully evaluated in European waters is the utilisation of restored saltmarsh habitats by fish species. This study examines the utilisation of managed realignments and relic saltmarsh by fish species. Factors affecting habitat heterogeneity and fish populations are discussed, and recommendations are made with respect to scheme design and management that will maximise the biological and socio-economic values. Fish populations in the high intertidal areas were assessed using a suite of techniques, including observations on feeding behaviour. Each microhabitat was discussed as a function of the extent of fish colonisation. A positive relationship between the degree of fish utilisation and habitat heterogeneity was ascertained using species richness, abundance and behavioural observations. This study will aid habitat valuation for economic justification of managed realignments, over and above existing drivers, such as compensatory habitat for encroachment, flood defence and the European Union Habitats Directive. The work now forms part of a wider European Interreg IIIb project, COMCOAST.  相似文献   

Stimulation of acetylcholinesterase activity by triiodothyronine in the brain of Singi fish,Heteropneustes fossilis (Bloch)     

Srabani De  A. K. Dasmahapatra  A. K. Medda 《Fish physiology and biochemistry》1993,10(5):419-424

Three consecutive days of injections of triiodothyronine (T₃)(0.038, 0.075, 0.15 and 1.54 nmoles/g) significantly elevated the acetylcholinesterase (AchE) activity in the brain of Singi fish, Heteropneustes fossilis (Bloch). The higher doses of 0.075, 0.15 and 1.54 nmoles of T₃/g induced a greater increase in enzyme activity than 0.038 nmoles/g. A T₃ dose of 0.019 nmoles/g was found to be ineffective. The T₃ action on AchE activity was blocked by cycloheximide. Thiourea treatment for 30 days decreased the AchE activity below the control level. This reduced level of the enzyme activity was brought back even above the control level by T₃ injections. It is, therefore, suggested that thyroid hormone is involved in the sustenance of AchE activity in fish brain.  相似文献   

水体表面浮植水蕹菜养鱼     

叶奕佐  杜健鹰  熊德聪  朱允中 《水产学报》1991,15(2):161-164,176

随着草食性鱼类养殖的迅速发展,青饲料供不应求和青饲料地十分紧缺等问题日益突出。为寻求解决这些问题,作者于1985—1988年进行了水体表面浮植水蕹菜养鱼的研究工作。现将主要研究结果报道如下。  相似文献   

Biological actions of atrial natriuretic factor in flatfish   总被引：1，自引：0，他引：1  

D. Arnold-Reed  Dr N. Hazon  R. J. Balment 《Fish physiology and biochemistry》1991,9(3):271-277

Flounder adapted to seawater were chronically cannulated and received a single i.v. injection of either saline (control) or 10 µg/kg b.w. of human ANF. Compared to controls, ANF significantly reduced (p<0.001) mean arterial blood pressure; full recovery was evident after 4 hours. Blood samples taken at intervals after saline or ANF injection showed that ANF caused a marked increase of 33.7 µg/100 ml in plasma cortisol concentration (p<0.001) 5 hours post injection. The rate of recovery of²²Na in seawater after a single i.v. injection of 14×10⁶ cpm/kg²²NaCl was significantly increased (p<0.01) following ANF injection compared to controls suggesting that ANF stimulates Na⁺ efflux. This observation was confirmed in plaice and dab. The steroidogenic action of ANF and its ability to promote Na⁺ efflux are discussed in relation to its potential osmoregulatory role in teleost fish.  相似文献   

鱼在腌制过程中水份活度和有关参数的变化关系     

尹文娟  郭晓峰  包建强 《水产学报》1987,11(4):315-321

本文研究了腌制鱼的水分活度(Aw值)变化及其与其他有关参数的关系。以鲳鱼作为试验原料,用混合腌渍法对鱼品进行不同时间的腌制,然后观察鱼体中水分活度、盐分含量和水分含量的变化情况,并进一步探索这些参数之间相互的变化关系。实验结果表明,鱼体中水分活度和水分含量的降低,盐分的增加均在开始腌制至18小时时为最快;18小时后变化缓慢;34小时后基本趋向平衡。实验表明,水分活度,盐分含量与水分含量之间存在简单的线性关系,因此在腌制过程中,测定出水分和盐分含量就可以计算出水分活度Aw值,从而达到控制鱼品质量的目的。此方法在提高鱼品的保藏效果上具有一定的实用价值。  相似文献   

Fish species richness in lakes of the northeastern lowlands in Germany   总被引：1，自引：0，他引：1  

R. Eckmann 《Ecology of Freshwater Fish》1995,4(2):62-69

Fish species richness was assessed by electrofishing and gillnetting in 16 lakes of the northeastern lowland in Germany (the Schorfheide biosphere reserve). The lakes range from 0.03 to 10.55 km² and support between 5 and 14 fish species. Species richness is significantly correlated with lake area in an exponential and a power model. Richness is also correlated with shoreline development and total dissolved solids. This supports the hypothesis that larger areas contain more species within a taxonomic group due to increased habitat diversity. The slope of the species-area curve is low compared with most other studies of fish species richness in lakes, and the intercept value is high. This is interpreted as the result of high habitat and food diversity, lack of stress from abiotic factors, and the small regional species pool from which these lakes can be colonized. Two species inventories, one from the beginning of this century and one from the 1950s, are available for comparison. Average species richness did not change during the last decades. Species turnover rates were not related to the degree of anthropogenic eutrophication or to the intensity of fishery exploitation in these lakes. On the species level, however, one effect of accelerated eutrophication is apparent, the disappearance of 4 bottom-living species from one to 6 of the study lakes.  相似文献   

大鹏澳网箱养殖海域磷酸盐在沉积物-海水界面交换速率的研究     

李占东  林钦  黄洪辉 《南方水产》2006,2(6):25-30

应用实验室培养法研究了大亚湾大鹏澳网箱养殖海域磷酸盐(PO_4-P)在沉积物-海水界面上的交换通量；并根据改进的连续函数法计算了PO_4-P在沉积物-海水界面上交换速率。结果表明：(1)PO_4-P在沉积物-海水界面上的交换通量随时间的变化关系满足以e为底的指数衰减函数；(2)整个调查海域PO_4-P在沉积物-海水界面上的交换速率为0．27～2．47 mmol·m~(-2)·d~(-1)。其中,网箱养殖区PO_4-P的交换速率(0．82～2．47 mmol·m~(-2)·d~(-1))明显高于对照区PO_4-P的交换速率(0．27～0．62 mmol·m~(-2)·d~(-1)),长时期的养殖活动使养殖区沉积环境中的磷得以积累,PO_4-P在沉积物-水界面上的交换速率升高。  相似文献   

稚鱼生物饵料的DHA营养强化   总被引：8，自引：0，他引：8  

张利民 《齐鲁渔业》1996,13(5):36-38

综述了国内外海水稚鱼生物饵的ＤＨＡ营养强化技术研究及其应用状况，轮虫、卤虫的营养强化方法和注意事项。  相似文献   

巨大芽孢杆菌MPF-906对养鱼水质净化的初步研究   总被引：9，自引：0，他引：9  

杨艳  刘萍  马鹏飞  孙君社 《水产养殖》2007,28(3):6-8

以鲫鱼为对象,利用从水产养殖水体中分离得到的巨大芽孢杆菌MPF-906,研究了其微生态制剂同步净化养鱼水质的动态变化。结果显示,在水族箱中添加巨大芽孢杆菌MPF-906制剂后,与对照组相比,水中的亚硝酸盐显著降解,COD也有所下降,pH值稳定在7.78￣8.19之间,表明巨大芽孢杆菌微生态制剂对净化养鱼水质和调节养殖水体微生态结构稳定具有明显的作用,其最适使用浓度为4×108CFU/mL。  相似文献   

抑制消减杂交（SSH）及其在鱼类基因克隆中的应用     

程起群 《水产学报》2004,28(3):323-328

和其它脊椎动物一样,在鱼类的生命进程中,某种特定类型的细胞中只有比例约为10%～15%的基因表达.由于这些基因的特异性决定了从受精卵到机体死亡的整个生命过程,所以这些基因的时空表达是受到严格调控的.在不同发育阶段,不同生理状态和不同类型的细胞中,表达的基因各不相同.因此,比较两种不同类型细胞中基因表达的差异,可以探究表型的遗传原因,了解生命过程的基本信息,从而找到与发育、疾病等相关的基因.  相似文献