• Korean Journal of Soil Science and Fertilizer
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• v.27 no.4
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• pp.290-295
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• 1994

Soil $CO_2$ evolution was measured using the soda-lime method for 20-year-old L. tulipifera, P. albaglandulosa, and Q. rubra plantations planted on a similar soil type in the Kwangneung Experimental Forest during the growing season of 1994. Soil $CO_2$ evolution ranged from $0.21g/m^2/hr$ for Q. rubra to $0.33g/m^2/hr$ for L. tulipifera. and was significantly different among species. We found positive correlations between soil $CO_2$ evolution and air(p<0.001, r=0.39) and soil temperatures(p<0.001, r=0.49). Peaks in seasonal soil $CO_2$ evolution occurred in July and August. Seasonal soil $CO_2$evolution did not necessarily follow changes in air and soil temperatures. This study implies that more work is needed to clarify the influence of other factors on soil $CO_2$evolution.

• Korean Journal of Agricultural and Forest Meteorology
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• v.5 no.2
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• pp.110-115
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• 2003

The iufluence of abandonment of agricultural fields on soil carbon and nitrogen dynamics is rarely addressed due to lack of appropriately paired sites. In this study, we identified three sites that have native forest and abandoned rice and crop fields at Mt. Kumdan near Seoul. Currently the vegetation of indigenous forest and the abandoned rice field is deciduous hardwood forest, while that of the abandoned crop field is deciduous shrub. We measured soil $CO_2$ evolution and inorganic N availability for the three sites from 25 July 2002 through 24 January 2003. Soil $CO_2$ evolution tracked seasonal soil temperature. Mean soil $CO_2$ evolution (g $CO_2$/$m^2$/hr) for the study period was 0.42 for the rice field to forest, 0.50 for the crop field to shrub, and 0.41 for the indigenous forest, respectively. Soil $CO_2$ evolution and soil temperature were not different among the sites; however, soil water content was significantly different. Soil water content had a very weak influence on soil $CO_2$ evolution. Inorganic resin N availability differed among the three sites and seemed to be related to soil moisture.

• Korean Journal of Environmental Agriculture
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• v.24 no.3
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• pp.238-244
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• 2005

Fertilization effects on changes in soil $CO_2$ flux and organic C in switchgrass (Panicum virgatum L.) land managed for biomass production were investigated. The mean daily soil $CO_2$ flux in the manure treatment was 5.63 g $CO_2-C\;m^{-2}\;d^{-1}$, and this was significantly higher than the mean value of 3.36 g $CO_2-C\;m^{-2}\;d^{-1}$ in the control. The mean daily $CO_2$ fluxes in N and P fertilizer treatments plots were not different when compared to the value in the control plots. Potentially mineralizable C (PMC), soil microbial biomass C (SMBC), and particulate organic C (POC) were highest at the 0 to 10 cm depth of the manure treatment. Potentially mineralizable C had the strongest correlation with SMBC (r = 0.91) and POC (r = 0.84). There was also a strong correlation between SMBC and POC (r = 0.90). Our results indicated that for the N and P levels studied, fertilization had no impact on temporal changes in soil organic C, but manure application had a significant impact on temporal changes in soil $CO_2$ evolution and active C constituents such as PMC, SMBC, and POC.

• The Korean Journal of Ecology
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• v.24 no.3
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• pp.141-147
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• 2001

Soil respiration and some environmental factors which affect soil respiration were studied in an oak forest, Kongju, Korea. Soil respiration was measured at midday of the 15th and 30th day at every month in control(Con), artificial forest gap (Gap) and litter removed area (Lr) with portable CO₂ Analyzer equipped soil respiration chamber. In July, maximum soil respiration in Con, Cap and Lr was 15.6, 11.2 and 7.7 CO₂μmol·m/sup -2/·s/sup -1/, respectively. Respiration in Gap and Lr decreased by 28.6% and 50.6%, respectively, compared with that in Con. Annual amount of soil CO₂ evolution from Con, Gap and Lr was 6.86, 5.84, 3.81 kg·m/sup -2/·yr/sup -1/, respectively. Annual amount of CO₂ evolution in Gap and Lr decreased by 14.8% and 44.5%, respectively, compared with that in Con. Soil respiration rates exponentially increased with temperature. Temperature of soil surface and at 5 cm depth was strongly related to soil respiration rates in Con (r₂＝0.87, 0.93), Gap (r₂=0.81, 0.88) and Lr (r/sub 2/=0.89).

• 한국생물공학회:학술대회논문집
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• 2001.11a
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• pp.578-581
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• 2001

A treatability study was conducted using a hydrocarbon-contaminated soil for the oPtimization of bioremediation strategy best fit to a given set of contamination. The applicability of nutrients, biosurfactant, and oil-degrading microorganisms were examined by monitoring $CO_2$ evolution and oil degradation The addition of inorganic nutrients in the form of slow released fertilizer accelerated the initial rate of $CO_2$ evolution by a factor of 3. The application of oil-degrading microorganisms did not significantly increased $CO_2$ evolution or biodegradation efficiency. Application of a commercial biosurfactant was most effect in terms of the total $CO_2$ evolution and the oil degradation rate. The results indicate that $CO_2$ evolution measurement was found to be a simple and reliable countermeasure of crude oil hydrocarbon mineralization for the rapid determination of the best-fit bioremediation strategy.

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 2002.04a
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• pp.199-202
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• 2002

Many methods have been developed for the remediation of contaminated soil and groundwater. Among those technologies, in-situ bioremediation is most likely to be cost-effective method for petroleum hydrocarbon contamination. But the in-situ bioremediation can require more time to remediate hydrocarbon-contaminated soil and groundwater than other methods. Therefore we intended to save time of in-situ bioremediation using a biological additive to activate indigenous microbes in soil. The additive, 'Inipol EAP 22' stimulates the growth of specific flora, significantly accelerating the speed at which hydrocarbons are biodegraded. And it hans been tested in accordance with protocol approved by the USEPA and is registered on the National Contingency Plan Product Schedule List. In the experiment, three soil samples contaminated with fuel oil were prepared in the same concentration. Inipol EAP 22 was not added to one sample and was added to the other two samples with 5% and 10% of hydrocarbon by weight respectively. And $CO_2$gas derived from bacterial respiration was analyzed in each samples for 15 days. As a result, 145% and 153% of $CO_2$ evolution (microbial respiration) against the sample without 'Inipol EAP 22' occurred in samples with 'Inipol EAP 22' addition of 5% and 10%, respectively

• Korean Journal of Environmental Agriculture
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• v.16 no.4
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• pp.320-326
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• 1997

In order to elucidate the degradation characteristics of the herbicide imazapyr in soil, mineralization to $^{14}CO_2$and adsorption were investigated using eight types of soils with the different physico-chemical properties. The results obtained were as follows: 1. During the incubation period of 12 weeks after the treatment of imazapyr, the amounts of $^{14}CO_2$ evolved from 8 types of soils with different properties ranged from 1.5 to 4.9% of the originally applied $^{14}C$ activities. Soil C, G, and H with low pH and high organic matter showed low $^{14}CO_2$evolution, whereas soil B and D with high pH and low organic matter did high $^{14}CO_2$ evolution. 2. Time for reaching the equilibrium concentrations in the adsorption experiment of imazapyr in soils was about 3 hours at $25^{\circ}c$ in soil C, D, G, and H. Imazapyr was adsorbed in the range of 0.25${\sim}$28.32% in soils with different physico-chemical properties. Among the soil parameters, organic matter content was the most influential in imazapyr adsorption on soil. The Freundlich adsorption coefficient $(K_f)$ increased 5.5 to 25.6 times as organic matter content increased 2.0 to 21.3 times. Hence it seems that the extent to which soil organic matter contributes to imazapyr adsorption is greater than that of clay mineral. $K_f$ values for the soils tested were 0.44, 0.08, 0.65, and 2.05 in soil C, D, G, and H, respectively. In all the soils tested, $K_f$ values had a strong resemblance to K_$K_d$.

• Korean Journal of Environment and Ecology
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• v.26 no.6
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• pp.902-910
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• 2012

This study has been carried out to determine the effects of disturbances from wild boar grubbing on the functions of ecosystem. The experiments was performed in Mt. Jumbong of Long-term Ecological Research Sites of the Ministry of Environment. We measured soil physical properties, soil respiration($CO_2$), microbial biomass C, and soil enzyme activities from both disturbed and control plots. The disturbance sites were divided into two parts, mounds and pits. Soil organic matter contents were highest value at the control plots and lowest at the pit plots, respectively at 20.22% and 15.52%. The soil bulk densities were highest at the pit plots. Soil microbial biomass C and $CO_2$ evolution were significantly higher at the control plots compared to the disturbed plots. The results were positively correlated with soil organic matter contents. The cellulase activity and invertase activity in the soil showed similar pattern as the microbial biomass C and $CO_2$ evolution results. The cellulase activity and invertase activity in the soil were positively correlated with soil microbial biomass C. Soil organic matter contents seemed to affect the soil enzyme activities. The nitrate reductase activities were highest at the pit plots, which showed positive correlation with soil bulk density. The study results showed that the grubbing disturbances by wild boars induced the changes in soil properties, which affected soil microbial activities.

• The Korean Journal of Ecology
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• v.26 no.3
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• pp.129-134
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• 2003

Amounts of CO₂ fixed by net primary production and released by soil respiration were determined on big-cone pine plantation. Net primary production, which was determined by allometric method, was converted into CO₂. CO₂ evolution in forest ecosystems are mainly through soil and root respiration. In order to separate root respiration from soil respiration, root-free sites were made in stand. Litter removal sites were prepared to estimate CO₂ evolution through litter layer. Respiration was measured at every two weeks intervals from April 2001 through April 2002, and soil temperature and soil moisture were measured at the same time. Net primary production of this big-cone pine plantation was 25.7 t·ha/sup -1/·yr/sup -1/. The amount of CO₂ fixed by this plantation was 42.5 t CO₂·ha/sup -1/·yr/sup -1/, The amount of CO₂ released by soil respiration was 5.0 t CO₂·ha/sup -1/·yr/sup -1/. The relative contribution of root respiration and litter layer respiration to total respiration was 46% and 32%, respectively. Net amount of fixed CO₂ was 37.5 t CO₂·ha/sup -1/·yr/sup -1/ in this big-cone pine plantation. From this result, this big-cone pine plantation play a carbon sink source from the atmosphere.

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 2000.11a
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• pp.87-90
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• 2000

The hydrogeochemical and isotopic studies on deep groundwater in the Munkyeong area, Kyeongbuk province were carried out. $CO_2$-rich groundwater (Ca-HC $O_3$ type) is characterized by low pH (5.8~6.5) and high TDS (up to 2,682 mg/L), while alkali groundwater (Na-HC $O_3$ type) shows a high pH (9.I~10.4) and relatively low TBS (72~116 mg/L). $CO_2$-rich water may have evolved by $CO_2$ added at depth during groundwater circulation. This process leads to the dissolution of surrounding rocks and Ca, Na, Mg, K and HC $O_3$ concentrations are enriched. The low Pc $o_2$ (10$^{-6.4}$atm) of alkali groundwaters seems to result from the dissolution of silicate minerals without a supply of $CO_2$. The $\delta$$^{18}$ O and $\delta$D values and tritium data indicate that two types of deep groundwater were both derived from pre-thermonuclear meteoric water. The carbon Isotope data show that dissolved carbon in the $CO_2$-rich water was possibly derived from deep-seated $CO_2$ gas. The $\delta$$^{18}$ S values of dissolved sulfate show that sulfate reduction occurred at great depths. The application of various chemical geothermometers on $CO_2$-rich groundwater shows that the calculated deep reservoir temperature is about 130~175$^{\circ}C$. Based on the geological setting, water chemistry and environmental isotope data, each of the two types of deep groundwater represent distinct hydrologic and hydrogeochemical evolution at depth and their movement is controlled by the local fracture system.m.