This study was carried out to apply the UAV(Unmanned Aerial Vehicle) coupled with Multispectral sensor for the algae bloom monitoring in river. The study acquired remote sensing data using UAV on the midstream area of Gum River, one of four major rivers in South Korea. Normalized difference vegetation index (NDVI) is used for monitoring algae change. This study conducted water sampling and analysis in the field for correlating with NDVI values. Among the samples analyzed, the chlorophyll concentration exhibited strong and significant linear relationships with NDVI, and thus NDVI was chosen for algae bloom index to identify emergence aspect of phytoplankton in river. Aerial remote sensing technology can provide more accurate, flexible, cheaper, and faster monitoring methods of detecting and predicting eutrophication and therefore cyanobacteria bloom in water reservoirs compared to currently used technology. As a result, there was high level of correlation in chlorophyll-a and NDVI. It is expected that when this remote water quality and pollution monitoring technology is applied in the field, it would be able to improve capabilities to deal with the river water quality and pollution at the early stage.

Recently, advanced metering infrastructure (AMI) has been recognized as a core technology of smart water grid, and the relevant market is growing constantly. In this study, we developed all-in-one smart water meter of the AMI system, which was installed on the test-bed to verify both effectiveness and field applicability in office building water usage. Developed 15 mm-diameter smart water meter is a magneto-resistive digital meter, and measures flow rate and water quality parameters (temperature, conductivity) simultaneously. As a result of the water usage analysis by installing six smart water meters on various purposes in office building water usage, the water usage in shower room showed the highest values as the 1,870 L/day and 26.6 liter per capita day (LPCD). But, the water usage in laboratory was irregular, depending on the many variables. From the analysis of the water usage based on day of the week, the water usage on Monday showed the highest value, and tended to decrease toward the weekend. According to the PCA results and multivariate statistical approaches, the shower room (Group 3) and 2 floor man’s restroom sink (Group 1-3) have been classified as a separate group, and the others did not show a significant difference in both water use and water quality aspects. From the analysis of water usage measured in this study, the leak or water quality accident did not occur. Consequently, all-in-one smart water meter developed in this study can measure flow rate and water quality parameters (temperature, conductivity) simultaneously with effective field applicability in office building water usage.

본 논문은 최근 몇 년 동안 어류폐사가 발생했던 하천 인 월운천, 서천, 장남천 그리고 안양천을 대상으로 어종 의 변동을 조사하였다. 어류폐사의 영향을 받은 지역에서 종수의 회복률은 22~86%까지 이르렀는데, 인공구조물 과 수질에 의한 영향을 받았다. 장남천에서는 알칼리성 pH로 인해 어류폐사가 발생하였으나 다른 두 하천(월운 천, 서천)에 비해 수질의 회복 이후 빠른 종수의 회복을 보였다. 또한, 안양천에서의 낮은 종수는 간헐적으로 발 생하는 용존산소고갈로 인한 수질악화의 영향이 크다. 이 와 더불어 하천에 설치되어 있는 인공구조물은 특히 저 서성 어종의 회복에 부정적인 영향을 주는 것으로 나타 났다. 수질 또는 어류개체군의 이동이 회복될 때 어종의 빠른 회복이 예상되지만, 여전히 많은 하천에서 수질의 악화현상과 일부 노후화한 인공구조물의 존재는 어류의 서식환경을 악화시킬 수 있고 어류폐사 이후 하천에서 어종의 회복을 지연시키는 원인이 될 수 있다. 하천에서 어류군집의 보존을 위해서는 어류의 이동을 위한 통로와 유역으로부터의 오염원의 유입을 관리하여야 한다.