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1.
菲律宾蛤仔和栉孔扇贝的呼吸与排泄研究   总被引:14,自引:0,他引:14       下载免费PDF全文
王芳 《水产学报》1997,21(3):252-257
对菲律之后人蛤仔和栉孔扇贝的呼吸与排泄进行了实验研究。结果表明:温度和贝体重对两种贝类的耗氧率的氨排泄率都有明显的影响,且两者间存在着交互作用。菲律宾蛤仔的耗氧率(Qo,mg/g/h)和氨排泄率(QN,μg/g/h)与温度(T,℃)(W,g)存在下列关系:Qo=0.307W^-0.738 1.004^T,QN=7.841W^-0.919 0.990^T;栉孔扇贝的耗氧率和氨排泄率与温度、湿重存在下  相似文献
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刘力  高尚德 《水产学报》1987,11(3):233-240
室内晾干不同时间(2—12小时)四种海藻失水达90%。晾干2—12小时对紫菜的毛光合有促进作用。晾干7小时内对石莼的毛光合有促进作用,8小时出现抑制作用;晾干5小时内对礁膜的毛光合有促进作用,6小时出现抑制作用;不同时间晾干的孔石莼电光合均低于对照。晾干2—12小时,四种海藻的净光合速率均有下降,而呼吸作用均受到了不同程度的促进。  相似文献
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温排水对围隔生态系统各粒级海洋浮游生物的影响   总被引:2,自引:0,他引:2       下载免费PDF全文
为了评价电厂温排水对海洋浮游生态系统的影响,2010年10月5日—11日于象山港宁海国华电厂附近海域,根据该海域表层海水温度的变化梯度设计围隔实验,测定围隔中各粒级海洋浮游生物生物量(B),呼吸率(R)和初级生产率(P)以及浮游生态系统的总初级生产量与总呼吸量的比值(TPP/TR)和周转率。分析结果表明,在25.20~26.40 ℃,0.25 ℃的温升对各粒级浮游生物的B,R和P的影响均不明显,0.52 ℃的温升对小型和微型浮游生物的R和P均有一定的促进作用,但对B的影响均不明显,对微微型浮游生物的B,R和P的影响不明显;在25.20~26.40 ℃,0.52 ℃的温升使该浮游生态系统的TPP/TR和周转率分别提高了1.2倍和1.5倍。本研究为评价温排水对海洋生态系统的影响提供了一定依据。  相似文献
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海洋酸化对栉孔扇贝钙化、呼吸以及能量代谢的影响   总被引:2,自引:0,他引:2  
通过Alkalinity anomaly technique测定了栉孔扇贝Chlamys farreri在不同酸度条件下的钙化率和呼吸率,发现栉孔扇贝的钙化和呼吸活动受酸化影响显著,均随着酸化的加剧出现了明显下降。当pH降低到7.9时,栉孔扇贝的钙化率将会下降33%左右;当pH降到7.3左右时,栉孔扇贝的钙化率将趋近于0,栉孔扇贝无法产生贝壳,而此时栉孔扇贝碳呼吸率(RC)与耗氧率(RO)也分别下降了14%和11%。随着酸化的加剧,栉孔扇贝的能量代谢方式也会发生改变。这些变化都可能影响到栉孔扇贝的生存。  相似文献
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Abstract –  This study examined whether habitat use by the African anabantid fish Ctenopoma muriei is consistent with predictions relating to two costs of air breathing (surface travel and aerial predation). We predicted that C. muriei would be most abundant in habitats that minimize potential costs of air breathing. We quantified environmental correlates of C. muriei abundance within a series of wetland lagoons in Uganda and found that C. muriei was more abundant in shallow waters of the deepest lagoon, in vegetated habitats, and at a depth 15–30 cm below the surface. These locations may minimize cost of travel to the surface for aerial respiration, while maintaining a reasonable distance from the surface to avoid detection by aerial predators. In addition, we experimentally tested effectiveness of vegetative cover in reducing mortality of C. muriei by aerial predators (pied kingfishers) using enclosures with and without vegetation cover in a swamp pool. We found that the presence of vegetative cover significantly reduced susceptibility of C. muriei to predation by pied kingfishers when dissolved oxygen in the water was low and air-breathing frequency was potentially high.  相似文献
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SUMMARY: This study was designed to determine the critical photon irradiance for growth and daily compensation point of juvenile Sargassum macrocarpum . Sampling and measurement of natural light conditions were carried out in the S. macrocarpum population at a depth of 8 m off Kiwado in Fukawa Bay, Yamaguchi Prefecture, Japan, from April to June 1998. Photosynthesis and respiration of the juvenile thalli, and diurnal changes in solar irradiance were measured for the same period. The critical photon irradiance for growth of the juvenile thalli observed on the population floor was 1.0–1.5% on the sea surface. The photosynthetic rate of leaf of juvenile thalli increased linearly with increasing photon irradiance when light levels were lower than 50 μM/m2 per s. The respiratory rate and light compensation point of the juvenile thalli were 2.49 μL O2/cm2 per h and 4.98 μM/m2 per s, respectively. The daily compensation point was estimated with a mathematical model based on photosynthesis–light equations and diurnal changes in solar irradiance. For a day of average solar irradiance over the period of the present study, the estimated daily compensation point of the juvenile thalli was 1.3% on the sea surface. This value agreed well with the observed critical photon irradiance for growth of juvenile S . macrocarpum on the population floor. The results of the study confirm that the mathematical model is effective for estimating the daily compensation point.  相似文献
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Fish in a population of Pagothenia borchgrevinki in McMurdo Sound, Antarctica, are affected by a gill disease (X-cell disease) which causes tissue hyperplasia that results in a decreased gill surface area and an increased water/blood diffusion distance. P. borchgrevinki acquires 95% of its oxygen via the gills, but damage to the gills by X-cell disease did not affect this function. There was no compensatory shift to cutaneous respiration. X-cell disease reduced the ability for oxygen uptake at low ambient PO 2 and the decreased uptake was related to the extent of the disease. O 2 max was greatly reduced in X-cell affected fish and substantially reduced their aerobic potential. This effect may impair the ability of diseased fish to catch prey and avoid predators.  相似文献
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In this paper, the performance of flow-through systems with constant flow rate, alternating open-closed systems, and monophase oxystats for determination of aquatic respiration rates are compared based on computer simulations at steady-state and non steady-state conditions. In most situations, monophase oxystats offer several advantages compared to the other, more frequently used respiratory systems. Monophase oxystats always operates at steady-state dissolved oxygen concentrations and therefore, this principle is less sensitive to noise on oxygen measurements since changes in dissolved oxygen concentration do not need to be measured in order to obtain accurate respiration rates. Furthermore, in monophase oxystats, experiments can be carried out under more precisely defined conditions and experimental animals are allowed better options to adapt to the experimental conditions compared to other respiratory systems. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献
10.
Changes in heart rate, ventilatory activity and oxygen consumption were determined in trout (Salmo gairdneri) and brown bullhead catfish (Ictalurus nebulosus) during exposure to a steadily increasing concentration of waterborne cyanide selected to produce death in 8–9 hours for each species. The lethal cyanide concentration for the bullheads was an order of magnitude higher than for trout. Trout developed an immediate and gradually increasing bradycardia throughout the exposure period. Cyanide produced tachycardia in the bullhead followed by a gradual onset of bradycardia as the concentration of cyanide was raised. Pericardial injection of atropine (a muscarinic cholinergic antagonist) indicated that bradycardia in the trout was due initially to increased vagal tone but later due to the direct effect of cyanide on the heart. Hyperventilation in the trout persisted throughout the exposure period, although the rate and amplitude fluctuated and was variable between individual fish. During the last hour of exposure (highest cyanide concentration), ventilation was characterized by rapid, shallow breaths followed by a sudden respiratory arrest. The bullheads exhibited hyperventilation during the first 3 hours of exposure followed by a gradual, linear drop in ventilation rate and amplitude until death occurred. Cardiac and ventilatory responses in both species were attributed to stimulation of central and peripheral chemoreceptors by cyanide. Evidence is presented which suggests the initial response in the bullheads was due, at least in part, to gustatory stimulation by the cyanide. Oxygen consumption of the trout remained above pre-exposure levels for the majority of the test period. Oxygen consumption in the bullhead paralleled the changes in heart and ventilatory rates. Whole-body lactate levels of fingerlings of both species during cyanide exposure were measured to estimate the extent of anaerobiosis. Whole-body lactate levels were much greater in the bullheads than the trout, indicating a higher capacity for anaerobiosis, possibly due to a greater fuel supply. Overall, the trout responded to cyanide in a manner similar to that produced by environmental hypoxia whereas the bullheads experienced a gustatory stimulus which masked the hypoxia-like response.  相似文献
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