This study presents a remote sensing approach of using freely available Landsat 8 satellite Indicators (Land Surface Temperature (LST), Soil Adjusted Vegetation Index (SAVI)) and Shuttle Radar Topography Mission (SRTM) Digital Elevation Model (DEM) geospatial data to assess the impact of dumpsites on the environment in Benin City, Nigeria. The finding reveals that the average derived LST at the dumpsites were higher than the immediate surrounding, and the average SAVI values were lower than the immediate surrounding. The high values of LST at the dumpsites depict the effect of gases released because of decomposition activities, while low values of SAVI indicate vegetation response to soil and ground water contamination due to leachate infiltration. The average elevation within the dumpsite area derived from SRTM DEM was also applied as a proxy to estimate disposed waste quantity, and related closely with LST that depict biodegradation activities. The result presented here shows that bacterial and fungal counts correlate strongly with the LST and SAVI values at each of the dumpsites R 2 : LST vs Bacteria Count = 0.982, LST vs Fungi Count = 0.951; SAVI vs Bacteria Count = 0.745, SAVI vs Fungi Count = 0.664, thereby suggesting remote sensing can be applied to aid longterm dumpsite monitoring and management.

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Recently, landslide due to natural disasters such as large-scale typhoons, or local torrential rain as a consequence of climate change, has become a serious problem for effective and detailed management of infrastructure safety. Particularly, slopes at risk of large-scale landslide in the future should be evaluated across the entire slopes for the behavior of groundwater infiltration from heavy rainfall. It is very important to establish monitoring techniques to visualize rainwater infiltration across entire slopes for the long term management of landslide risks. The authors developed a new electrical exploration system for remote-controlled measurement. We conducted a continuous electrical survey over a period of two years at two slope sites in order to monitor rainwater infiltration of landslide slopes. Based on resistivity changes during rainfall events of 50-100 mm, the findings indicate that rainwater rapidly infiltrated shallower sediments to depths of a few meters during rainfalls, and evaporated slowly after rainfall ceased. We also estimate that rainwater penetrated slowly into deeper layers. The sampling period was limited to 50-60 days, due to frequent methodological challenges such as the severing of cables by wild animals and rock falls, and instrument failure caused by the thunderbolts at two sites. Furthermore, we were unable to continue the measurement during heavy rainfall events of more than a few hundred millimeters. The biggest factor is that the instruments were not protected from thunderbolts during storms. It is recommended that future studies should incorporate protective circuits for thunderbolts to double or triple insulation.

Coal-flyash concrete and ordinary concrete plates were immersed in the sea near Shin-Nagasaki fishing port, Nagasaki, Japan, for different periods from October, 2004, to January, 2006. The marine sessile organisms that settled on these plates were studied. Throughout the study period, barnacles (Amphibalanus amphitrite, B. trigonus), bryozoans (Bugula neritina), ascidians (Styela plicata), some species of polychaetes, and algae were observed settling on both kinds of plate. Wet weights of organisms on the two types of plate were the same. These results indicate that coal-flyash concrete is suitable for use in constructing artificial fishing reefs, as a substitute for usual concrete.

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