• Korean Journal of Ecology and Environment
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• v.42 no.1
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• pp.9-18
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• 2009

The objectives of this study were to evaluate seasonal and interannual variations of water quality and nutrient input (N, P) in Junam Reservoir, a nesting waterbody of migratory birds, over 10 years during 1998$\sim$2007 along with dynamic relations of trophic parameters using empirical models. Concentrations of COD averaged 7.8 mg $L^{-1}$ during the study, while TN and TP were $1.4\;mg\;L^{-1}$ and $83{\mu}g\;L^{-1}$, respectively, indicating an eutrophic-hypereutrophic state. Values of monthly COD had strong positive relations (r=0.669, p<0.001) with conductivity, indicating that summer rainfall resulted in an ionic dilution of the reservoir water by rainwater and contributed better water quality. One-way ANOVA tests showed significant differences (F=$5.2{\sim}12.9$, p<0.05) in TN and TP between the before and after the bird migration. In other words, nutrient levels were greater in the absence of migratory birds than in the presence of the migratory birds, suggesting a no-effect on nutrient inputs by the birds. Also, one-way ANOVA indicated no significant differences (F=$0.37{\sim}0.48$, p>0.05) in $NO_{3^-}N$ and $NH_{3^-}N$ between the before and after the birds migration. Linear empirical models using trophic parameters showed that algal biomass as CHL, had significant low correlations with TN ($R^2$=0.143, p<0.001, n=119) and TP ($R^2$=0.192, p<0.001, n=119). These results suggest that influences of nutrients on the CHL were evident, but the effect was weak. This fact was supported by analysis of Trophic State Index Deviation (TSID). Over 70% in the observed values of "TSI (CHL)-TSI (SD)" and "TSI (CHL)-TSI (TP)" were less than zero, suggesting a light limitation on the CHL by inorganic suspended solids.

• Journal of the Korean Society of Groundwater Environment
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• v.1 no.2
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• pp.105-112
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• 1994

To investigate the migration behavior of contaminants in rocks. adsorption and diffusion experiments for Sr as a sorbing contaminant and for Cr-EDTA as a non-sorbing contaminant were carried out on granitic rocks. The Sr adsorption on separated minerals and crushed rocks tends to slightly increase with increasing pH. It also greatly decreases with the increase of ionic strength in NaCl solution. Among separated minerals, biotite and sericite have adsorbed much more amount of Sr than other rock-forming minerals, such as quartz, plagioclase, and potassic feldspar, because the specific surfaces and cation exchange capacities of phyllosilicates are generally much greater than those of the other rock-forming minerals. The intrinsic diffusion coefficients of Cr-EBTA for granitic rocks differ little from those of Sr. This indicates that they are independent of water-rock interactions. Experimental data show that the intrinsic diffusion coefficients are positively correlated with the porosities of the rocks. They are close to the theoretically predicted values, especially in pre-steady state diffusion region, with the increase of rock sample thickness.