• Journal of Wetlands Research
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• v.19 no.1
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• pp.172-179
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• 2017

The purpose of this study is to analyze the current original habitat and to conserve the narrow-mouthed toad populations. For this study, we used 240 pitfall traps (30 cm height ${\times}$ 20 cm width) to catch the narrow-mouthed toads that inhabit in Myeongji-dong, Gangseo-gu, in Busan metropolitan city from August 2, 2013 to November 7, 2013. We measured the environmental characteristics (soil composition factors, soil moisture, Humidity, soil temperature) for the seven habitat patterns of narrow-mouthed toads based on vegetation types. Main habitats of narrow mouthed toads were flat grassland where grass and false acacia grew and there was wetland all over the place. When analyzing habitats that main habitats of narrow-mouthed toads prefer after selecting representative seven vegetation, it was found that the most narrow-mouthed toads were caught in amur silver grass colony while the least narrow-mouthed toads were caught in bare land. Totally, we caught 846 narrow-mouthed toads over 68 times, and released them into the newly constructed habitat after injection VIE-tag. It seems that the reason for which the least narrow mouthed toads were caught in bare land is that bare land is not suitable for narrow mouthed toads to protect themselves from strong sunlight and to hide themselves from natural enemy. We found that temperature had the greatest influence on activities of narrow mouthed toads and at temperature of less than $15.6^{\circ}C$. We also found that the activities of narrow mouthed toads were remarkably low and then temperature was below $15.6^{\circ}C$. It meant that narrow mouthed toads seemed to go into hibernation. From this research, we could find the prefer habitat after analyzing habitats for the narrow-mouthed toads and could suggest for construction for the better habitat of narrow-mouthed toads.

• Korean Journal of Environmental Agriculture
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• v.27 no.4
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• pp.373-381
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• 2008

To select of optimum rice species and germanium (Ge) application method for production of functional rice with Ge, the growth characteristics, Ge absorption and grain quality of rice plant were investigated under different rice species (Hopyungbyeo, Junambyeo, Ilmeebyeo and Dongjinbyeo) and Ge application method (soil application and foliar spray). The rice yield by soil application was higher in the order of Hopyungbyeo $\fallingdotseq$ Junambyeo > Ilmeebyeo >> Dongjinbyeo. On the other hand, the rice yield by foliar spray was higher in the order of Junambyeo >> Ilmeebyeo > Dongjinbyeo > Hopyungbyeo. The rice yield by soil application was higher than that by foliar spray regardless of rice species. For soil application, the Ge absorption in various parts of the rice was higher in the other of rice bran > brown rice > polished rice regardless of rice species. The Ge absorption of brown rice in Hopyungbyeo, Ilmeebyeo, Dongjinbyeo and Junambyeo by soil application was 14.5, 8.0, 11.6 and $10.4\;mg\;kg^{-1}$, respectively. In leaf, stem and root, the Ge absorption by foliar spray was higher than that by soil application, whereas, in rice bran, brown rice and polished rice, the Ge absorption by soil application was higher than that by foliar spray. The optimum rice species and Ge application method were demonstrated to be Hopyungbyeo and soil application, respectively, which provided suitable conditions for production of functional rice with Ge.

• Korean Journal of Ecology and Environment
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• v.43 no.1
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• pp.44-54
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• 2010

In this study, a comprehensive exploration and evaluation of washland candidate locations by means of field monitoring as well as spatial analysis in six major river system (Han, Nakdong, Nam, Geum, Youngsan, and Seomjin Rivers). Washland(in other words, river detention basin) is an artificial wetland system which is connected to streams or rivers likely to riverine wetlands. Major purpose of washland creation is to control floodings, water supply and purification, providence of eco-cultural space to human and natural populations. Characteristics and functions of riverine wetlands can be expected as well, thus it is believed to be an efficient multi-purpose water body that is artificially created, in terms of hydrology and ecology. Geographical information and field monitoring results for the washland candidate locations were evaluated in 2009, with respect to optimal location exploration, ecosystem connectivity and educational-cultural circumstances. A total of $269\;km^2$ washland candidate locations were found from spatial analysis (main channel of Rivers South Han, 71.5; Nakdong 54.1; Nam, 2.3; Geum, 79.0; Youngsan 46.4; Seomjin 15.7), and they tended to be distributed in mid- to lower part of the rivers to which tributaries are confluent. Field monitoring at 106 sites revealed that some sites located in the Rivers Nam and Geum is appropriate for restoration or artificial creation as riverine wetlands. Several sites in the Nakdong and Seomjin Rivers were close to riverine wetlands (e.g., Upo), habitats of endangered species (e.g., otters), or adjacent to educational facility (e.g., museums) or cultural heritages (e.g., temples). Those sites can be utilized in hydrological, ecological, educational, and cultural ways when evidence of detailed hydrological evaluation is provided. In conclusion, determination of washland locations in the major river basins has to consider habitat expansion as well as hydrological function (i.e. flood control) basically, and further utility (e.g. educational function) will increase the values of washland establishment.

• Korean Journal of Environmental Agriculture
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• v.26 no.3
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• pp.217-222
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• 2007

To investigate effects of inorganic $(GeO_2)$ and organic (Ge-132) germanium (Ge) on seed germination and on early stage growth of plane and the uptake characteristics, various concentrations (0, 10, 25, 50, 100 mg $L^{-1}$) of Ge to popular vegetables such as leaf mustard, chinese cabbage and pak-choi, respectively, were treated. On seed germination, no significant effect was observed in both inorganic and organic Ge treatments except 100 mg $L^{-1}$ treatment of inorganic Ge. Exogenous inorganic Ge ($10{\sim}100$ mg $L^{-1}$ treatments significantly inhibited the early root elongation growth of all plants. However, slight enhancement of early shoot elongation was detected in low concentrations (10 and 25 mg $L^{-1}$) of Ge in the leaf mustard and chinese cabbage plants. Organic Ge treatments significantly stimulated the 개ot and shoot growth at the 10, 25 and 50 mg $L^{-1}$ treatments. Ge was accumulated linearly in the vegetables as both inorganic and organic Ge concentrations were increased. Interestingly, total contents of Ge in plants with Ge-132 treatments were $2\sim4.5$ times more than those with inorganic Ge treatments in all concentrations. At 25 mg $L^{-1}$ treatment of Ge, contents of Ge in vegetables are following: in leaf mustard, inorganic Ge: 0.37 mg $g^{-1}dw$ and organic Ge: 1.47 mg $g^{-1}dw;$ in the chinese cabbage, inorganic Ge: 0.4 mg $g^{-1}dw$ and organic Ge: 0.86 mg $g^{-1}dw;$ in the pak-choi, inorganic Ge: 0.33 mg $g^{-1}dw$ and organic Ge: 0.70 mg $g^{-1}dw$, respectively. These results showed organic Ge is much better on early stage seedling growth and on germanium accumulation of vegetables than inorganic Ge.

• Journal of Wetlands Research
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• v.25 no.4
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• pp.335-344
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• 2023

Brachydiplax chalybea flavovittata, a climate-sensitive biological indicator species, was first observed and recorded at Jeju Island in Korea in 2010. Overwintering was recently confirmed in the Yeongsan River area. This study was aimed to predict the potential distribution patterns for the larvae of B. chalybea flavovittata and to understand its ecological characteristics as well as changes of population under global climate change circumstances. Data was collected both from the Global Biodiversity Information Facility (GBIF) and by field surveys from May 2019 to May 2023. We used for the distribution model among downloaded 19 variables from the WorldClim database. MaxEnt model was adopted for the prediction of potential and future distribution for B. chalybea flavovittata. Larval distribution ranged within a region delimited by northern latitude from Jeju-si, Jeju Special Self-Governing Province (33.318096°) to Yeoju-si, Gyeonggi-do (37.366734°) and eastern longitude from Jindo-gun, Jeollanam-do (126.054925°) to Yangsan-si, Gyeongsangnam-do (129.016472°). M type (permanent rivers, streams and creeks) wetlands were the most common habitat based on the Ramsar's wetland classification system, followed by Tp type (permanent freshwater marshes and pools) (45.8%) and F type (estuarine waters) (4.2%). MaxEnt model presented that potential distribution with high inhabiting probability included Ulsan and Daegu Metropolitan City in addition to the currently discovered habitats. Applying to the future scenarios by Intergovernmental Panel on Climate Change (IPCC), it was predicted that the possible distribution area would expand in the 2050s and 2090s, covering the southern and western coastal regions, the southern Daegu metropolitan area and the eastern coastal regions in the near future. This study suggests that B. chalybea flavovittata can be used as an effective indicator species for climate changes with a monitoring of their distribution ranges. Our findings will also help to provide basic information on the conservation and management of co-existing native species.

• Korean Journal of Soil Science and Fertilizer
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• v.39 no.5
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• pp.321-327
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• 2006

In Korea, there is a growing competitive for water resources between industrial, domestic and agricultural consumer, and the environment as many other OECD countries. The demand on water use is also affecting aquatic ecosystems particularly where withdrawals are in excess of minimum environmental needs for rivers, lakes and wetland habits. OECD developed three indicators related to water use by the agriculture in above contexts : the first is a water use intensity indicator, which is expressed as the quantity or share of agricultural water use in total national water utilization; the second is a water stress indicator, which is expressed as the proportion of rivers (in length) subject to diversion or regulation for irrigation without reserving a minimum of limiting reference flow; and the third is a water use efficiency indicator designated as the technical and the economic efficiency. These indicators have different meanings in the aspect of water resource conservation and sustainable water use. So, it will be more significant that the indicators should reflect the intrinsic meanings of them. The problem is that the aspect of an overall water flow in the agro-ecosystem and recycling of water use not considered in the assessment of agricultural water use needed for calculation of these water use indicators. Namely, regional or meteorological characteristics and site-specific farming practices were not considered in the calculation of these indicators. In this paper, we tried to calculate water use indicators suggested in OECD and to modify some other indicators considering our situation because water use pattern and water cycling in Korea where paddy rice farming is dominant in the monsoon region are quite different from those of semi-arid regions. In the calculation of water use intensity, we excluded the amount of water restored through the ground from the total agricultural water use because a large amount of water supplied to the farm was discharged into the stream or the ground water. The resultant water use intensity was 22.9% in 2001. As for water stress indicator, Korea has not defined nor monitored reference levels of minimum flow rate for rivers subject to diversion of water for irrigation. So, we calculated the water stress indicator in a different way from OECD method. The water stress indicator was calculated using data on the degree of water storage in agricultural water reservoirs because 87% of water for irrigation was taken from the agricultural water reservoirs. Water use technical efficiency was calculated as the reverse of the ratio of irrigation water to a standard water requirement of the paddy rice. The efficiency in 2001 was better than in 1990 and 1998. As for the economic efficiency for water use, we think that there are a lot of things to be taken into considerations to make a useful indicator to reflect socio-economic values of agricultural products resulted from the water use. Conclusively, site-specific, regional or meteorogical characteristics as in Korea were not considered in the calculation of water use indicators by methods suggested in OECD(Volume 3, 2001). So, it is needed to develop a new indicators for the indicators to be more widely applicable in the world.