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1.
Effects of water temperature (17, 21, 25, 30 and 35℃) and body size (14.75-281.41 g initial body weight) on food consumption, growth, feed conversion, and dry matter content in orange-spotted grouper fed to satiation were investigated. The combined effect of temperature (T, ℃) and body weight (W, g) on maximum food consumption (Cmax, g/day) was described as: InCmax=-7.411+0.828 InW+0.317T4).004 7T2, and the optimum feeding temperature was 33.9℃. The combined effect of temperature and body weight on growth (G) was described as: lnG=-4.461-0.2081nW+0.394T-0.006 3T^2. The optimum growth temperature was 31.4℃, whereas overall growth rates were high at 25, 30 and 35 ℃. Feed conversion efficiencies (FCE, %), increasing first and then decreasing with increasing temperature, averaged from 1.8 to 2.1 in terms of dry weight of food fish. The optimum temperature for FCE tended to be lower than that for growth or feeding. Dry matter content increased with both increasing water temperature (17, 25, 30 and 35℃) and body weight, and the combined effect of temperature and body weight on dry matter content (DM, %) was described as: lnDM =3.232+0.01 4 lnW-0.004 4T+0.001 2TInW.  相似文献   

2.
1 INTRODUCTION Chironomid larvae are main groups in most aquatic ecosystems, playing a crucial ecological role in decomposition of detritus and material ex- changes between water column and the sediment (Liang et al., 1995a, b; Chen, et al., 1982). They a…  相似文献   

3.
Reproductive rate of a marine planktonic copepodLabidocera euchaeta Giesbrecht in Xiamen Harbor bor was studied during the period from April 1986 to August 1987. Results showed that rate of egg production (F, eggs/(♀, d)) was positively correlated with temperature (T,oC) and body weight of spawning female (Wc, μgC) as:F=0.0637 (T−7)0.7445 Wc. Each month a maximum rate of egg production occurred at one of the five experimental temperatures (10°, 15°, 25°, and 30°C) near the monthly mean field temperature. The available food density (P, μgC/ml) had significant effect on specific rate of egg production (Fc, %C ♀/d) as:Fc=0.1732 (P-0.0179)/P. The gross efficiency of egg production of ca 62% in carbon was independent of food density snd ingestion rate. Observations on in situ egg production and hatching rate demonstrated that this species reproduces continuously all the year round, with summer as its high reproductive season and winter a low one. Ten generations a year is also suggested based on the number of the peaks of average population egg production rate. This agreed well with the result obtained from the generation-time equations. Egg-laying pattern was also observed and discussed.  相似文献   

4.
Effects of temperatures and salinities on oxygen consumption and ammonia-N excretion rate of clamMeretrix meretrix were studied in laboratory from Oct. 2003 to Jan. 2004. Two schemes were designed in incremented temperature at 10, 15, 20, 25°C at 31.5 salinity and in incremented salinity at 16.0, 21.0, 26.0, 31.5, 36.0, and 41.0 at 20°C, all for 8–10 days. From 10 to 25°C, both respiration and excretion rate were increased. One-way ANOVA analysis demonstrated significant difference (P<0.01) in physiological parameters in this temperature range except between 15 and 20°C. The highestQ 10 thermal coefficient value (12.27) was acquired between 10 and 15°C, and about 1 between 15 and 20°C, indicatingM. meretrix could well acclimate to temperature changes in this range. Salinity also had significant effects on respiration and excretion rate (P<0.05). The highest values of respiration and excretion rate ofM. meretrix were recorded at 16.0 salinity (20°C). These two physiological parameters decreased as salinity increased until reached the minimumQ 10 value at 31.5 (20°C), then again, these parameters increased with increasing salinity from 31.5 to 41.0.M. meretrix can catabolize body protein to cope with osmotic pressure stress when environmental salinity is away from its optimal range. No significant difference was observed between 26.0 and 36.0 in salinity (P>0.05), suggesting that a best metabolic salinity range for this species is between 26.0 and 36.0. This work is supported by National High-Tech R & D Program of China. (863 Program) (2002AA603014).  相似文献   

5.
Effects of temperature, salinity and light intensity on growth rates of Gracilaria lichenoides and G. tenuistipitata var. liui Zhang et Xia were tested. Eight to ten levels of each factor were first tested separately. The best growth rate was obtained under the conditions of 32°C, 30 and 240 μmol/(m2·s) for G. lichenoides, and 24°C, 20 and 200 μmol/(m2·s) for G. tenuistipitata, respectively. Then a uniform design was used to evaluate the optimal combinations of the three factors. The best conditions for the highest daily specific growth rates (% increase in wet weight) are determined to be 31.30°C, 32.10, and 287.23 μmol/(m2·s) for G. lichenoides (16.26%/d), and 25.38°C, 21.10, and 229.07 μmol/(m2·s) for G. tenuistipitata (14.83%/d), respectively. Supported by the 908 Special Program (908-02-04-07), the National Basic Research Program of China (973 Program, No. 2006CB400608), and K. C. Wong Magna Fund in Ningbo University  相似文献   

6.
Effects of reduced salinity on the oxygen consumption rate (OCR) and the ammonia-N excretion rate (AER) of scallopChlamys farreri (3.2–5.9 cm in shell height, 0.147–1.635 g in soft tissue dry weight) were studied in laboratory from March 21, 1997 to April 16, 1997. Under the controlled conditions of reduced salinity from 31.5 to 15.0 and ambient temperature 17°C and 23°C, the concentrations of dissolved oxygen and ammonia-N were determined by the Winkle method and the hypobromite method, respectively. Results showed that with controlled reduced salinity, the mean values of the OCR were 2.17 mg/(g.h) at 17°C, and 2.86 mg/(g.h) at 23°C and that the mean values of the AER were 178.0 μg/(g.h) at 17°C and 147.0 μg/(g.h) at 23°C. The OCR and the AER decreased with reducing salinity from 31.5 to 15.0 both at 17°C and 23°C. The effects of reduced salinity on the OCR and the AER of scallopC. farreri could be represented by the allometric equation and the exponential equation, respectively. Contribution No. 3295 from the Institute of Oceanology, Chinese Academy of Sciences. Project supported by the National Ministry of Science and Technology of China and by the Chinese Academy of Sciences, Grant No. 96-922-02-04 and KZ951-A1-102-02.  相似文献   

7.
The energy budget ofBellamya earuginosa in a shallow algal lake, Houhu Lake (Wuhan, China) was investigated by the measurement of flesh production (32.8 kJ/(m2·a)), egestion (337.7 kJ/(m2·a)), metabolism (246.7 kJ/(m2·a)), and estimation of excretion (21.4kJ/(m2·a)). The net growth efficiency of the species is about 10.9%, which accords with the generally reported value for gastropods. In addition, the relationships between starvation respiration (R, mgO2/(Ind·d)), body weight (Wd, mg in dry wt) and temperature (T, °C) were also determined. The regression equationR=0.044Wd 0.537 e 0.061T was obtained by the least square method, The measured SDA of the species is 26.51% of its gross metabolism. Project No. 3960019 and 39430101 supported by NSFC and also a granted for the East Lake Ecological Experimental Station, CAS, Wuhan.  相似文献   

8.
Sand wedge is formed under the conditions of coldclimate, and is an important basis for reconstructingpaleoenvironment (LI et al., 1990; WANG, 1991 ). Ithas been reported constantly over the last 20 years inthe Qinghai-Xizang (Tibet) Plateau (GUO, 1979; CUl,1983; XU et al., 1984; LIANG et al.,, 1984; PAN etal., 199 ) and North China (YANG et al., 1983; DONGet al., 1985) and Northeast China (GUO et al.,1981 ). We also found fossil sand wedge groups formedin the end of the Late P…  相似文献   

9.
INTRODUCTIONTheJapaneseseabass (LateolabraxjaponicusC&V)distributeswidelyinthecoastalwatersalongtheBohaiSea ,YellowSea ,EastChinaSea,andSouthChinaSea .Asacarnivorousfish ,itoccupiesthehightrophiclevelinthemarineecosystemandhasadaptedtovariousenvironmentalr…  相似文献   

10.
In laboratory conditions, effects of rearing temperature and stocking density were examined on hatching of fertilized egg and growth of auricularia larvae of Apostichopus japonicus respectively. Data series like larval length and density, metamorphic time, and survival rate of the larvae were recorded. Statistics showed that for A. japonicus, survival rate (from fertilized egg to late auricularia) decreased significantly with the increasing rearing temperature (P<0.05). At different temperatures SGR was statistically significant as well (P<0.05) from day 1, and maximal SGR was found on day 9 at 24°C (159.26±3.28). This study clearly indicated that at low temperature (<24°C), metamorphic rate was remarkably higher than at higher temperature (>26°C). Hatching rate was significantly different between 0.2–5 ind./ml groups and 20–50 ind./ml groups. Rearing larvae at the higher density had the smaller maximal-length, whereas needed longer time to complete metamorphosis. This study suggested that 21°C and 0.4 ind./ml can be used as the most suitable rearing temperature and stocking density for large -scale artificial breeding of A. japonicus’s larvae.  相似文献   

11.
INTRODUCTIONThemetabolisminfishincludesstandardmetabolism(RS)routinemetabolism(RR),specificdynamicaction(SDA)andactivemetabolism(RA),relatedas:  RT=RS RR SDA RAwhereRSisthemetabolismofthefishatrest;RRthemetabolismoftheroutinelyactivefish;SDAthemetabolismofth…  相似文献   

12.
Effects of temperature on oxygen consumption rate (OCR) and ammonia—N excretion rate of scallopChlamys farreri (1.7–6.2 cm in shell height) were studied in laboratory from Dec. 30,1996 to Jan. 28,1997. Under the controlled conditions of ambient water temperature 10–31°C and salinity 32, the concentrations of dissolved oxygen and ammonia—N were determined by the Winkle method and the hypobromite method, respectively. Results showed that the OCR ranged from 1.20 mg/g (DW) · h to 5.76 mg/g (DW) · h. The OCR increased with temperature from 10°C to 23°C, but at 28°C the OCR of mature individuals decreased, and that of different size scallops reduced at 31°C. The ammonia—N excretion rate ranged from 113.03 μg NH4-N/g (DW) · h to 486.63 μg NH4-N/g (DW) · h, and increased with temperature from 10°C to 31°C. Contribution No.3180 from the Institute of Oceanology, Chinese Academy of Sciences. This work was supported by the National Commission of Science and Technology of China, Grant No.96-922-02-04.  相似文献   

13.
Chondrus is a type of commercially produced red seaweed that widely used for food and carrageen extraction. Although the natural life history of the alga had been well understood, the factors influencing development of the tetraspore and carpospore remain poorly understood. In the perspective of seedling resources, the regulation of early development is crucial for the seedling nursing; therefore, it is necessary to understand the physiological influences during its early development. In this study, we studied the effects of temperature and irradiance on the early development of Chondrus ocellatus Holm under laboratory conditions. The released tetraspores and carpospores were cultivated at different temperatures (10–28°C) and irradiances (10, 60 μmol photons m−2s−1) with a photoperiod of 12L:12D. The results indicate that both tetraspores and carpospores are tolerant to temperatures of 10–25°C, and have the highest relative growth rate at 20°C. Irradiance variances influenced the growth of the discoid crusts, and the influence was more significant with increasing temperature; 60 μmol photons m−2s−1 was more suitable than 10 μmol photons m−2s−1. The optimum temperature and irradiance for the development of seedlings was 20°C and 60 μmol photons m−2s−1, respectively.  相似文献   

14.
Wetland stores substantial amount of carbon and may contribute greatly to global climate change debate. However, few researches have focused on the effects of global climate change on carbon mineralization in Zoigê al-pine wetland, Qinghai-Tibet Plateau, which is one of the most important peatlands in China. Through incubation ex-periment, this paper studied the effects of temperature, soil moisture, soil type (marsh soil and peat soil) and their in-teractions on CO2 and CH4 emission rates in Zoigê alpine wetland. Results show that when the temperature rises from 5℃ to 35℃, CO2 emission rates increase by 3.3-3.7 times and 2.4-2.6 times under non-inundation treatment, and by 2.2-2.3 times and 4.1-4.3 times under inundation treatment in marsh soil and peat soil, respectively. Compared with non-inundation treatment, CO2 emission rates decrease by 6%-44%, 20%-60% in marsh soil and peat soil, respec-tively, under inundation treatment. CO2 emission rate is significantly affected by the combined effects of the tempera-ture and soil type (p < 0.001), and soil moisture and soil type (p < 0.001), and CH4 emission rate was significantly af-fected by the interaction of the temperature and soil moisture (p < 0.001). Q10 values for CO2 emission rate are higher at the range of 5℃-25℃ than 25℃-35℃, indicating that carbon mineralization is more sensitive at low temperature in Zoigê alpine wetland.  相似文献   

15.
The experimental results showed that: 1) The embryonic development of bay scallop is inhibited at a dissolved oxygen range of 1.38–3.64×10−3 at 23°C, and completely blocked below the lower limit. 2) The tolerance of larvae to anoxia increased with larval sizes and was related to their oxygen debt. 3) The scallop larvae exhibited specific behavioral responses to oxygen deficiency, which finally led to velum disintegration and larval death. The possible relationship between environmental oxygen deficiency and the disease of disintegration of the larval velum is also discussed. In this study, considerable oxygen debt was found in bay scallop larvae, which was greater in small animals. Based on the works of previous authors, a new concept is proposed for the estimation of oxygen debt, namely, the compensatory rate of oxygen debt (CROD). This can be used in intra—or interspecific comparison of oxygen debt. The results can be helpful in the management of water quality and for the prevention of larval diseases encountered in scallop culture. Contribution No. 2167 from the Institute of Oceanology, Chinese Academy of Sciences.  相似文献   

16.
Estivation, hibernation, and starvation are indispensable inactive states of sea cucumbers Apostichopus japonicus in nature and in culture ponds. Generally, temperature is the principal factor that induces estivation or hibernation in the sea cucumber. The present study provided insight into the physiological adaptations of A. japonicus during the three types of inactivity (hibernation, estivation, and starvation) by measuring the oxygen consumption rates (Vo2) and biochemical compositions under laboratory conditions of low (3°C), normal (17°C) and high (24°C) temperature. The results show that the characteristics of A. japonicus in dormancy (hibernation and estivation) states were quite different from higher animals, such as fishes, amphibians, reptiles, and mammals, but more closely resembled a semi-dormant state. It was observed that the shift in the A. japonicus physiological state from normal to dormancy was a chronic rather than acute process, indicated by the gradual depression of metabolic rate. While metabolic rates declined 44.9% for the estivation group and 71.7% for the hibernation group, relative to initial rates, during the 36 d culture period, metabolic rates were not maintained at constant levels during these states. The metabolic depression processes for sea cucumbers in hibernation and estivation appeared to be a passive and an active metabolic suppression, respectively. In contrast, the metabolic rates (128.90±11.70 μg/g h) of estivating sea cucumbers were notably higher (107.85±6.31 μg/g h) than in starving sea cucumbers at 17°C, which indicated that the dormancy mechanism here, as a physiological inhibition, was not as efficient as in higher animals. Finally, the principle metabolic substrate or energy source of sea cucumbers in hibernation was lipid, whereas in estivation they mainly consumed protein in the early times and both protein and lipid thereafter.  相似文献   

17.
Maximum rate of food consumption ( Cmax ) was determined for juvenile Sebastodes fuscescens (Houttuyn) at water temperature of 10, 15, 20 and 25℃. The relationships of Cmax to the body weight (W) at each temperature were described by a power equation: lnCmax = a b lnW. Covariance analysis revealed significant interaction of the temperature and body weight. The relationship of adjusted Cmax to water temperature (T) was described by a quadratic equation: Cmax = -0.369 0.456T - 0.0117T^2. The optimal feeding temperature calculated from this equation was 19.5 ℃. The coefficients of the multiple regression estimation relating Cmax to body weight (W) and water temperature (T) were given in the Table 2.  相似文献   

18.
The Gulf of Kachchh in western India, with its arid climate, large semi-diurnal tidal amplitudes, negative water balance and near-pristine water quality, is being extensively developed as oil importing bases for economic reasons in connection with its proximity to the oil exporting countries of the Middle East. Besides, new coral rubbings were sighted in Jakhau, north-western Gulf of Kachchh. Dredging in Mandvi of the north Gulf covering 3.5 km2 revealed a similar assortment of live corals with their associated flora and fauna. These pioneering observations demonstrate that there exist live corals of young polyps-colony of Favia sp. belonging to the family Faviidae in the north-western Gulf of Kachchh. The environmental parameters there were carefully recorded as: surface water temperature (°C) varying from 29 to 31.8, salinity (ppt), pH, dissolved oxygen (mgL−1) and total suspended solids (mgL−1) in the ranges of 37–43.5, 7.7–8.45, 5.4–6.8 and 11–31, respectively.  相似文献   

19.
Experiment on phosphorus budget of redeye mullet (Liza haematocheila T. & S.) was conducted at water temperature 21℃ and salinity 33. The results showed that the growth phosphorus (phosphorus that allocated into growth, GP) increased from -30.84% to 15.83% by feeding on graded amount of diets (starvation, 1%, 2%, 3%, 4% body weight and satiation). The GP linearly increased with feeding levels (FL) as GP (mg) = - 0.785 + 0.604 FL, and at satiation the relationship between GP and body weight (BW) was GP (mg) = 1,5991 BW0.7685. In the budget, IP (intake phosphorus) = GP + FP (faecal phosphorus) + EP (excretion phosphorus). FP showed an irregular tendency with different feeding levels, and EP decreased with increasing feeding levels but rebound at satiation. The P budget at satiation was 100IP = 15.84 GP + 64.62 FP + 19.55 EP.  相似文献   

20.
The relations between δ18O and temperature on the different time scales were analysed, according to the data from Tuotuohe (34°13′N, 96°25′E; 4533 m a. s. l.), Delingha (37°22′N, 97°22′E; 2981 m a. s. l.) and Xining (36°37′N, 101°46′E; 2261 m a. s. l.) in the Qinghai-Xizang Plateau. The results show that the significance of d δ18O/dT on different time scales are different. The d δ18O/dT on the synoptic scale reflects the interdependent relation between δ18O and temperature in the short-term synoptic scale process; the d δ18O/d T on the seasonal scale reflects the relation between them whithin a year; and the d δ18O/d T on the climatic scale reflects the relation between them in the long-term climatic change. The calculated d δ18O/dT on climatic scale is very close to the theoretical values on the condition of advection transport for Tuotuohe Station. However, there are great differences between the calculated and the theoretical values for Delingha and Xining stations.  相似文献   

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