| Title |
Effects of Water Temperature, Light and Dredging on Benthic Flux from Sediment of the Uiam Lake, Korea |
| Authors |
윤석제 ( Seok Jea Youn ) ; 김헌년 ( Hun Nyun Kim ) ; 김용진 ( Young Jin Kim ) ; 임종권 ( Jong Kwon Im ) ; 이은정 ( Eun Jeong Lee ) ; 유순주 ( Soon Ju Yu ) |
| DOI |
https://doi.org/10.15681/KSWE.2017.33.6.670 |
| Keywords |
Benthic flux; Dredging; Light; Sediment; Temperature |
| Abstract |
An experiment to study the effect of temperature, light, and dredging on release of nutrients downstream from Gongjicheon in the Uiam reservoir was carried out in the laboratory using sediments from different depths. At various water temperatures, dissolved total nitrogen was not released, but the average nutrient flux of dissolved total phosphorus was increased (0.034 at 15°C, 0.005 at 20°C, 0.154 at 25°C, 0.592 mg/㎡/d at 30°C). Dissolved total phosphorous was released in controlled darkness. In contrast, in controlled light, the concentrations of dissolved total phosphorous and dissolved total nitrogen in the overlying water steadily decreased during the study period (70 d), because they were continuously consumed by the growth of photosynthetic algae. However, there was no significant relationship between water nutrient concentration, nutrient release, and the depth of the sediment. We concluded that the dredging of sediment would not affect the nutrient release rate of the sediment, because there were no significant differences in the nutrient concentrations released from the sediment. When the sediment was removed from the surface to 20 cm in depth , the nutrients were not transferred to the water body, implying that the sediment removal had little effect on secondary pollution. |