• Journal of the Korean Society for Marine Environment & Energy
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• v.8 no.1
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• pp.9-16
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• 2005

A series of experiments was conducted to evaluate the effects of temperature on the survival, growth and sensitivity of the benthic amphipods, Mandibuluphoxus mai and Monocnrophium acherusicum, which have been recently developed as new sediment toxicity testing species in Korea. The biological performance for each amphipod species was determined by the survival and growth rates at different water temperatures. The influence of temperature on the sensitivity to reference toxicant, Cd, was determined by the comparison of survival rates of amphipods exposed to control and Cd-spiked seawater at different temperatures. Temperature significantly influenced on the survival, growth and Cd sensitivity of both amphipods. Tolerable ranges of temperature for the >80％ individuals of both M. mai and M. acherusicum with sediment substrates were mostly overlapped (13 to 22℃). The daily growth rates of M. mai and M. acherkisicum increased proportionally with temperature up to 20℃ and 25℃. respectively. Similarly, the sensitivities of M. mai and M. acheyusicum to Cd increased with temperature up to 20℃ and 15℃, respectively. Overall results showed that temperature is a substantially important factor potentially influencing the results of lethal and sublethal bioassays using the amphipods. Therefore, defining the adequate ranges of experimental temperature for the toxicity testing species is the pre-requisite for the development of standardized bioassay protocols.

• The Korean Journal of Malacology
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• v.24 no.3
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• pp.167-173
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• 2008

The survival and growth of Glossaulax didyma didyma ($R{\ddot{o}}ding$) were measured in the laboratory under controlled conditions, such as water temperature, salinity and diet. The effect of temperature on G. didyma didyma was examined at four different levels (15, 20, 25 and $30^{\circ}C$) with 30 psu for 30 days. The results show that the growth and survival rates of G. didyma didyma were significantly higher at $15^{\circ}C$ and $20^{\circ}C$ than at other temperatures. The effect of salinity on G. didyma didyma was also examined at six different levels (10, 15, 20, 25, 30 and 35 psu) in $20^{\circ}C$ for 40 days. The results showed that the growth and survival rates of G. didyma didyma were significantly higher at 30 psu and 35 psu than at other salinities. Finally, the effect of diets on G. didyma didyma was examined with three single-component diets (prawn, shellfish and fish) at $20^{\circ}C$ and 30 psu for 60 days. The results showed that the growth and survival rates of G. didyma didyma fed on shellfish were significantly higher than those fed on prawn and fish.

• The Korean Journal of Malacology
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• v.27 no.4
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• pp.337-343
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• 2011

In order to know the effects of rearing conditions such as water temperature, salinity, larval stocking density, kinds and amounts of food organism and seedling collection method on seedling production of the brackish water clam, Corbicula japonica, the growth and survival rate of the larvae were investigated at each rearing condition. The shell length of larvae showed faster growth at $24^{\circ}C$ and $27^{\circ}C$, and survival rate showed good results at $18^{\circ}C$ and $21^{\circ}C$. Based on growth and survival rate according to water temperature, the optimal water temperature for larvae rearing was $24^{\circ}C$. At the salinity of more than 3 psu, the growth and survival rate were higher than 0 psu. The optimal salinities for larvae were 6-9 psu. Growth and survival rate of larvae were high at low stocking density and the optimum stocking density of larvae was 10 inds./ml. Daily feeding concentrations of 10,000-20,000 cell/ml of food organisms mixed Pavolva lutheri, Isochrysis galbana and Chaetoceros calcitrans were very effective. Full grown larvae collection from various substratum was significantly higt in sand, especially sand size was less than 0.25 mm.

• Journal of Aquaculture
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• v.7 no.1
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• pp.9-20
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• 1994

To find out suitable indoor rearing tank shape and stocking density of the abalone Haliotis discus hannai, young abalones were reared in the square or ellipse shape tanks with various stocking densities and were fed dried sea mustard, Undaria Pinnatifida HARVEY for three years. There were no significant differences between the square rearing tank and the ellipse one in growth rate and survival rate. With regard to vertical design of rearing tanks with three floors, the significant differences were not found among culture floors. However, the growth and survival rates of young abalones from the running water system were significantly higher than those of the abalones from the circulating system (P< 0.05). For the stocking density experiment with 1,000, 1,500 and 2,000 individuals of 20 mm young abalone, there was no significant differences in growth and survival rates among these groups. However, in that of 200-400 individuals of 40 mm abalone and 100-300 individuals of 50 mm abalone, the lower stocking density of young abalone showed the higher growth and survival rates. The lower stocking density and the smaller size of young abalones showed the higher daily feeding rate and feed efficiency.

• Journal of agriculture & life science
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• v.45 no.4
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• pp.47-58
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• 2011

The forest of Korea had been severely degraded since early 1900s until 1950s. Korean Government has successfully accomplished the reforestation works since 1960s. However, some plantations showed poor survival and growth caused by ignoring site characteristics in selecting plantation species and lack of tending works such as thinning. The natural regeneration of indigenous species, such as Quercus species and Pinus densiflora Siebold & Zucc., were examined in the plantations of Pinus koraiensis Siebold & Zucc. and Larix kaempferi Fortune ex Gordon. Quercus species regenerated mainly by sprouting while P. densiflora regenerated naturally from a few mother trees that remained in the plantations. P. koraiensis showed poor survival ($IVI{\leq}25%$) and suppressed growth (height ${\leq}3m$ and $DBH{\leq}3cm$ at 20 year-old) by Quercus species or P. densiflora in the plantation areas, however had high survival ($IVI{\geq}70%$) and growth (8 m height and 14.1 cm DBH at 20 year-old) in areas where silvicultural practices were conducted. L. kaempferi showed good survival ($IVI{\geq}40%$) and growth (17.2 m height and 16.3 cm DBH at 30 year-old) mostly in valley areas, while it was nearly dead ($IVI{\leq}10%$) in ridge or ridge-slope areas and was replaced by indigenous species such as Quercus species ($IVI{\geq}25{\sim}55%$) or P. densiflora ($IVI{\geq}18{\sim}50%$).

• Journal of Marine Bioscience and Biotechnology
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• v.6 no.2
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• pp.123-130
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• 2014

Three types of artificial microparticle diets were developed for rotifer (Brachionus plicatilis) enrichment. The efficacies of enrichment with the artificial diets were evaluated and compared to those with commercial enrichment diets on the growth and survival of flounder larvae. Total lipid content was highest in the rotifer enriched with oil capsule (40.5% in dry weight). The n-3 highly unsaturated fatty acid (n-3 HUFA) content was also highest in the rotifer fed with oil capsule (7.08% in dry weight). The flounder larvae fed on the rotifer enriched with oil capsule showed the highest growth compared to those fed on any other enriched rotifer (P<0.05). The survival ratio of flounder larvae fed on the rotifers enriched with oil capsule and emulsion oil were higher than those fed on any other enriched rotifer (P<0.05). From the feeding study, the growth and survival of flounder larvae were enhanced by feeding rotifer enriched with oil capsule compared to rotifer enriched with any other diets. The rotifer fed on oil capsule containing high contents of n-3 HUFA. Therefore, a significant relationship between the growth and survival of flounder larvae and the n-3 HUFA content of rotifer could be obtained.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.53 no.1
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• pp.132-138
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• 2020

Marphysa sanguinea is the most well-known polychaete species with a high economic value. However, this species has a high mortality in the early rearing stage of aquaculture. This study was conducted to find out the optimal substrate size and organic contents for the growth and survival rate of M. sanguinea larvae and juveniles. It was observed that the smaller grain size (<Ø 0.063 mm) and high organic contents (5-10%) induced settlement and reduced settlement time of larvae. Moreover, the growth and survival rate of larvae reached high levels at Ø 0.004-0.016 mm of grain sizes and 5-7.5% of organic contents as advantageous substrates for settlement. The survival rate of juveniles reached over 90% in less than Ø 0.016 mm substrate on 15-day experiment for different grain sizes of substrates. These results indicated that substrate compositions of less than Ø 0.016 mm of sand size and 5-7.5% of organic contents in mud will enhance the productivity of M. sanguinea at the early stage.

• Journal of fish pathology
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• v.17 no.2
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• pp.139-144
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• 2004

In the present study, the effect of different water temperature (15, 20, 25, $30^\circ{C}$ and ambient) on survival, growth rate and intermolt period of zoeal and megalopal stage of tiger crab, Orithyia sinica were examined. The survival rate of zoeal and megalopal stages of experimental crab was observed high at $20^\circ{C}$ and ambient water temperature. The growth rate of crab larvae showed temperature-dependent increase. Therefore, the maximum growth rate was recorded at $30^\circ{C}$ temperature-regulated group in both zoeal and megalopal stage. However, temperature-dependent decrease in larval stages of crab during intermolt period has been observed in the present investigation.

• Journal of Korea Foresty Energy
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• v.22 no.3
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• pp.20-28
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• 2003

This study was subjected to compare seasonal changes of survival rate, relative growth rate, and chlorophyll contents of major oak tree species including Quercus acctissima, Quercus mongolica, Quercus serrata, Quercus varibilis seedlings grown in Quercus acctissima forest under different light intensities. Three light intensities were 81% of sunlight, 34% of sunlight and 21% of sunlight. In each treatment, 100 tree seedlings were planted and survival rate, growth rate, and chlorophyll contents were measured. The highest survival rate was Quercus acctissima in 73% seedlings compared with those subjected to the other tree seedlings in 45~66%. Lowest survival rate was Quercus vnriabilis seedlings in 41%. Oaks tree species of the height, the root collar diameters of the relative growth were better in the seedlings grown in 81% light intensities of full sun. But growth rates decreased rapidly in the shade treatment of 21% light intensities of full sun. Lowest chlorophyll contents(chlorophyll a, b and total) were shown at 21% light intensities of full sun, lowest light intensity treatment in this study This result is thought growth and chlorophyll contents associated with light intensity Also, Physiological characteristics has to be investigated in near future because photosynthesis and chlorophyll contents were strongly related to tree growth with long periods.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.36 no.1
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• pp.39-43
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• 2003

Experiments were carried out to investigate the effects of long term sub-lethal cadmium exposure on survival, growth and metabolic rate of olive flounder, Paralichthys olivaceus for 6 weeks. Survival rate of the flounder was significantly affected above $980{\mu}g/L$. Growth rates of the flounder exposed to ${\geq}210\;{\mu}g/L$ of cadmium concentration were significantly decreased than that exposed to normal condition, Metabolic rate in the cadmium concentration ${\geq}210\;{\mu}g/L$ was significantly reduced with increasing cadmium concentration than that in normal condition. This study revealed that high cadmium concentration $$({\geq}210\;{\mu}g/L$$ reduced growth and metabolic rate of the juvenile flounder suggesting potential influence on the natural mortality of olive flounder in the coastal areas.