• Journal of Fisheries and Marine Sciences Education
• /
• v.27 no.5
• /
• pp.1364-1368
• /
• 2015

This study was performed to evaluate mineral contents of catfish Silurus asotus. As a result of mineral content, the mean content of the macro mineral was (in descending order): K (310.36-412.66 mg/100 g), P (186.42-223.02 mg/100 g), Na (35.32-57.87 mg/100 g), Mg (22.88-31.87 mg/100 g), Ca (9.05-13.07 mg/100 g). In comparison, the mean content of the micro mineral was (in descending order): Fe (0.26-0.95 mg/100 g), Zn (0.26-1.02 mg/100 g), Cu (ND-0.08 mg/100 g), Mn (0.01-0.03 mg/100 g). A proportion of mineral intakes with the dietary reference intakes for Koreans (KDRIs) set by the Korean Nutrition Society. Nutrient uptake proportion of mineral intakes was (in descending order): P (62.16%), K (20.71%), Mg (16.82%), Fe (13.02%), Zn (11.38%) Cu (10.94%), Na (6.59%), Ca (3.09%), Mn (0.96%). The mineral content was compared with the major protein food sources according to the Korea Health Statistics (2013) such as polished rice, pork, chicken, beef, eggs and milk. The calcium content contains; lower level of milk and eggs, chicken whereas higher levels of rice, pork and beef. Catfish has less iron content than major protein food source. Phosphorus and potassium contain higher level of major protein food sources.

• Journal of the Korean Society of Environmental Restoration Technology
• /
• v.20 no.6
• /
• pp.93-105
• /
• 2017

This study aims to establish the integrated system of national protected areas by identifying OECMs which are not officially recognized as protected areas, but effectively and enduringly deliver the conservation of biodiversity and ecosystem service to expand them up to the level recommended by the international community. In order to identify them, candidates for OECMs were listed and it was developed a three-step systematic screening tool based on preconditions, essential characteristics, and sustainable means for conservation outcome of them. As a result of using the tool that considers domestic conditions, seven areas which included Development Restriction Zones, Urban Natural Park Areas, Fishery Resources Protection Zones, Riparian Zones, Natural Recreation Forest Zones, Water Source Protection Areas, and Buffer Zones for Korea National Arboretum were selected as OECMs. And the system of national protected areas was built by integrating them with national protected areas(NPA). Compared with the NPA, the system has been expanded by them and has reached to 17.88%, exceeding the target of 17% for terrestrial and inland water protections. It was proven that they were very effective in enlarging these protections. However, it failed to contribute to the target for marine protections. The expansion of marine protected areas requires different approaches, such as discovering new types of marine protected areas or linking them to biologically important marine areas all over the world.

• Korean Journal of Fisheries and Aquatic Sciences
• /
• v.41 no.6
• /
• pp.478-484
• /
• 2008

To elucidate the spawning behavior and early life history of Liobagrus mediadiposalis, mature male and female fish were collected from a branch of the Seomjin River. Spawning was induced by injecting hormones, and then the spawning process and development of fertilized eggs, larvae, and juveniles were observed. Observations of spawning behavior showed that the female established a territory and built a spawning nest, and frequently pressed on the upper ventral part of the male to release her eggs. When spawning was finished, the fish supplied fresh water to the egg mass using their pectoral and caudal fins. Hatching began 189 h 20 min after fertilization at $21.5-23.5^{\circ}C$ (mean $22.7^{\circ}C$). The mean total length (TL) of newly hatched larvae was 7.18-7.39 mm (mean 7.31 mm). Their mouth and anus were already open and they had 14+24=38 myotomes. Eighteen days after hatching, the larvae were 12.71-13.79 mm (mean 13.27 mm) in TL and the yolk sac was absorbed completely. At 35 days after hatching, when all the fin-rays had formed, the juveniles were 15.84-17.92 mm (mean 16.33 mm) in TL.

• Korean Journal of Ecology and Environment
• /
• v.53 no.2
• /
• pp.185-194
• /
• 2020

Pomacea canaliculate (channeled apple snail; CAS), which is one of the world's worst alien invasive species, is widely distributed in Korea, and raised ecological and economic problems. In this study, we surveyed the distribution and dispersal characteristics of CAS in Korea, and analyzed the effects of environmental and anthropogenic (or social) factors on their distribution and dispersal. We considered various events related to CAS such as changes of policy including promotion of agriculture using CAS and enactment of biological diversity conservation law. Our results showed that human activities strongly influenced to the distribution and dispersal of CAS in Korea. Distribution of CAS seemed to relate with environment-friendly agriculture considering environmental conditions of CAS habitats. And dispersal characteristics of CAS were significantly correlated with social factors such as cultivation area and rate of organic products, production CAS on inland fishery.

• Korean Journal of Fisheries and Aquatic Sciences
• /
• v.57 no.2
• /
• pp.177-185
• /
• 2024

We developed a regional ocean climate model using dynamic downscaling in the Northwest Pacific Ocean to build a climate model for the Korean Peninsula. The past marine environment was reproduced through historical simulations, and the future marine environment in 2100 was predicted according to the shared socioeconomic pathways (SSP) climate change scenario. The future sea surface temperature of the Korean seas is predicted to rise about 1-4℃, and the increase in water temperature in the East Sea is expected to be the largest. The National Institute of Fisheries Science has monitored abnormal seawater temperatures such as high and low seawater temperatures in coastal and inland waters, and predicted that the number of high seawater temperature days in the East, West, South Sea, and the coast of Jeju Island will increase in the future. In addition, the occurrence of Ciguatera fish poison plankton around Jeju Island was projected to increase. This study is expected to provide accurate forecasting information for fishery issues. The aim of this study was to analyze future ocean environment changes around the Korean Peninsula using climate change SSP scenarios and predict fisheries issues through future projections of the regional ocean climate model.

• Korean Journal of Fisheries and Aquatic Sciences
• /
• v.43 no.1
• /
• pp.46-53
• /
• 2010

Spawning behavior and early life history of the tuman river sculpin, Cottus hangiongensis were studied in the laboratory and in the field at Wangpi Stream, Gyeongsangbuk-do, Korea, from January to December, 2007. The spawning ground was in the lower Wangpi Stream, which is a shallow region about 40cm or less in depth. During the spawning period, from March to April, mature males made nest cavities under stone 10 which they led a gravid female. The male and female then turned upside down, and spawning and fertilization occurred onto the ceiling of the nest cavity. After spawning, the male chased the female from the nest and mated with several other females. Fertilized eggs were spherical in shape, demersal, adhesive, transparent and yellow in color, measuring 1.86 mm (1.79~1.93 mm) in diameter. A mean of 17(12~22) various-sized oil globules were counted in the yolk. Granular materials formed a mass in the yolk. Fertilized eggs hatched at 256 hrs, 10 minutes after the morula stage under water temperature of $15.0{\sim}18.0^{\circ}C$. Newly hatched larvae 9.34 mm (9.02~9.69 mm. n=10) in total length (TL) had a large yolk At 14 days after hatching, larvae 11.40 mm (11.07~11.72 mm, n=10) in TL transformed to the postlarval stage. At 41 days after hatching, postlarvae of 18.42 mm (17.31~18.62 mm, n=10) in TL had reached the juvenile stage. The result of this study indicate that Cottus hangiongensis has the spawning ground in the lower stream and the amphidromous life history which is the different from that of Cottus poecilopus.

• Journal of Korean Society of Environmental Engineers
• /
• v.37 no.11
• /
• pp.631-635
• /
• 2015

Water quality investigation was conducted for small/medium sized reservoirs in A city in June and November 2014 as a preliminary step for further use. Water quality analysis experiments were conducted for 21 reservoirs managed by a local government and water quality data were obtained from Korea Rural Community Corporation for 12 reservoirs. It was found that relatively poor water quality, not satisfied with the regulation level (somewhat poor(IV)) for agricultural use, was observed for some reservoirs and worse water quality (poor(V) and very poor(VI) grade) was observed for more reservoirs during autumn /winter season due to the decrease in water volume. Correspondingly, the trophic state was obtained as "Eutrophic" or "Hypertrophic" using the Korean trophic state index for most reservoirs. It was also revealed that significant contamination in sediments was not observed for selected 8 reservoirs considering water quality in each reservoir. The results in this study could be useful for the use of small/medium sized reservoirs as alternative water resources, tourism resources, inland fishery resources, renewable energy production sites, and anti-flooding reservoirs.

• Korean Journal of Ichthyology
• /
• v.19 no.4
• /
• pp.350-359
• /
• 2007

The egg development and morphological change of larvae and juveniles of the starry flounder, Platichthys stellatus were observed in laboratory. Fertilized eggs of the species, 1.09~1.19 mm (mean $1.13{\pm}0.03mm$, n=50) in diameter, were floating, colorless, transparent in shape and lacked in oil globules. The eggs hatched out 121 hours after fertilization at water temperature $8.2{\sim}11.2^{\circ}C$. The size of the hatched larvae were 2.58~2.89 mm (mean $2.67{\pm}0.09mm$) in total length, their mouth and anus were not open yet and myotome number was 14+27=41. Melanophore and xanthophore appeared on the notochord and digestive organ and the margin of membrane fin, on the yolk sac and eyes were lacking in pigment cells. 5 days after hatching the larvae attained 4.30~4.97 mm (mean$4.74{\pm}0.21mm$) in TL, and their mouth and anus were open. 10 days after hatching the larvae transformed to postlarval stage and they were 4.67~5.75 mm in TL (mean $5.30{\pm}0.31mm$), and absorbing the yolk completely. Feeding activity increased as the mouth became larger. At 23 days, the larvae attained 6.69~8.82 mm in TL (mean $7.85{\pm}0.75mm$), and the right eye was started moving to the left side of the head. At 52 days, the juveniles attained 10.99~17.06 mm in TL (mean $13.50{\pm}1.67mm$). The right eye was moved completely onto the left side. All of the fins had completed set of the fin rays (D. 64~67: A. 45~51: P. 11: V. 6: C. 19).

• Journal of Wetlands Research
• /
• v.20 no.4
• /
• pp.398-409
• /
• 2018

Organic farming practices including loach based ecosystem-farming have been demonstrated to be effective in conjunction with rice farming to increase yield and quality. This new form of farming combines agriculture and fishery and is quickly developing into a new industry. The current study investigated the effect of rice-fish mixed farming system on the vegetation-diversity function. Vegetation within the four study sites was surveyed and analyzed based on plant taxonomy. The vegetation survey demonstrated that 127 taxa of 38 families, 100 genera, 107 species, and 20 varieties occurred within the study sites. A total of 15 plant species taxa occurred in the rice-fish mixed paddy fields with a fish habitat and did not occur in the conventional paddy field lacking fish habitat. This difference is thought to arise from differences in moisture requirements for vegetation. Life form analysis demonstrated differences in hemicryptophytes, therophytes, and hydrophytes according to fish habitat. The naturalized plants identified were also determined to be species widely distributed throughout Korea. Frequency analysis demonstrated that the rice-fish mixed paddy fields with a fish habitat had a high ratio of both obligate and facultative wetland plants relative to the conventional paddy field. Based on the study results, it is likely that vegetation-diversity will increase with environment diversity. However, no statistical significance was observed according to paddy types. Future research should aim to identify additional environmental factors, including the existence of fish habitat, habitat area, depth of fish habitat, hydrological parameters, water quality, and paddy soil environment, to enhance vegetation-diversity and biocultural diversity.