• Journal of Wetlands Research
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• v.6 no.1
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• pp.117-132
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• 2004

Despite its significance in understanding ecological structure and biogeochemical element cycles, there have been few studies on the microbial mineralization of organic matter and mineralization pathway in the intertidal flat of Korea. We measured anaerobic mineralization of organic matter and sulfate reduction rate, and evaluated the significance of sulfate reduction in total anaerobic carbon respiration at the southern part of Ganghwa Island. Depth-integrated carbon mineralization rate down to 6 cm depth ranged from 41.9 to $89.4mmol\;m^{-2}d^{-1}$, which accounted for approximately 216 tons of organic matter mineralization in entire intertidal flat area of Ganghwa($300km^2$). The results indicated that capacity for the organic matter mineralization in the Ganghwa tidal flat is comparable to highly productive salt marsh environments. Mineralization rates in the sediment amended with acetate were 2~5 times higher than in unamended sediment. The results implied that microbial mineralization was limited by the availability of organic substrates, and the organic matter mineralization capacity seems to be higher than estimated at ambient organic substrate level. Depth-integrated sulfate reduction rates within 6 cm depth of the sediment ranged from 20.7 to $45.1mmol\;SO{_4}^{2-}m^{-2}d^{-1}$, and sulfate reduction was mostly responsible for organic matter remineralization. It should be noticed that the increase of $H_2S$ in the sulfate reduction dominated tidal flat may result in the decrease of biological diversity.

• Journal of the Korean Society of Food Science and Nutrition
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• v.33 no.1
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• pp.66-71
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• 2004

This study has been carried out to investigate effect of Rehmanniae Radix (RR) and pear phenolic compound (PC) on the hyperglycemic mice induced with streptozotocin (STZ). For this purpose, male mice were fed with a 0.2 mL RR extract (S group) and the pear PC (90 mg/kg/day) dissolved in a 0.2 mL RR extract (SPC group) while the control group received the same commercial diet for 6 weeks. The blood glucose contents were examined from tail vein blood once a week for 6 weeks. Samples of pancreas removed after the experimental period were processed for the immunohistochemical identification of $\beta$-cells. The levels of serum glucose were decreased significalntly (p<0.05) in the S and SPC groups compared with the control group. The BUN and creatinine levels were significantly (p<0.05) decreased in SPC group compared with the control group. Intraperitoneal glucose tolerance tests peformed at 24 hours before that period revealed that glucose tolerances in S and SPC group were ameliorated. Immunohistochemical analyses of the pancreases revealed that a lot of insulin- positive $\beta$-cells were contained in a Langerhas's islets of S and SPC groups compared with the control group, and the number of Langerhas's islets were significalntly increased in S (p<0.01) and SPC (p<0.05) groups. These results suggest that RR extract and pear PC could recover the damages induced by STZ in the hyperglycemic mice.

• Korean Journal of Agricultural and Forest Meteorology
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• v.12 no.4
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• pp.307-316
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• 2010

Complex terrain refers to irregular surface properties of the earth that influence gradients in climate, lateral transfer of materials, landscape distribution in soils properties, habitat selection of organisms, and via human preferences, the patterning in development of land use. Complex terrain of mountainous areas represents ca. 20% of the Earth's terrestrial surface; and such regions provide fresh water to at least half of humankind. Most major river systems originate in such terrain, and their resources are often associated with socio-economic competition and political disputes. The goals of the TERRECO-IRTG focus on building a bridge between ecosystem understanding in complex terrain and spatial assessments of ecosystem performance with respect to derived ecosystem services. More specifically, a coordinated assessment framework will be developed from landscape to regional scale applications to quantify trade-offs and will be applied to determine how shifts in climate and land use in complex terrain influence naturally derived ecosystem services. Within the scope of TERRECO, the abiotic and biotic studies of water yield and quality, production and biodiversity, soil processing of materials and trace gas emissions in complex terrain are merged. There is a need to quantitatively understand 1) the ecosystem services derived in regions of complex terrain, 2) the process regulation occurred to maintain those services, and 3) the sensitivities defining thresholds critical in stability of these systems. The TERRECO-IRTG is dedicated to joint study of ecosystems in complex terrain from landscape to regional scales. Our objectives are to reveal the spatial patterns in driving variables of essential ecosystem processes involved in ecosystem services of complex terrain region and hence, to evaluate the resulting ecosystem services, and further to provide new tools for understanding and managing such areas.