Municipal waste generation and management is a global phenomenon. This paper has critically examined the trends in waste generation and management in Nigerian urban areas. Drawing largely from related works reviewed, the paper has discovered that the rate of waste generation is 25 million tonnes per year, at a daily rate of 0.44-0.66 kg/capita/day while the density of the country ranges from 280-370 kg/m3. Further findings indicated that increased municipal waste management problem stemmed from such unethical practices of dumping wastes in streams, runways, drainages, open spaces and burning of combustible materials that release smoke and particulate matter in the environment to threaten flora, fauna and human beings. These approaches to wastes management have adverse consequences on human beings as the wastes readily become breeding ground for disease-causing organisms like rodents and insects. The paper concluded by recommending the need for public enlightenment on the menace of filthy environment, provision of waste management facilities, establishment of waste -recycling plants and encouraging more research activities into ways of recycling wastes in order to make the urban environment habitable.
Freshwater springs and natural hot-water springs, alpine, subalpine lakes and the Mediterranean temporary ponds in Mt Oiti and Mt Kallidromos, coastal lakes, lagoons and marshes in the coastal zones of Maliakos gulf, and the protected wetlands that exist in the area of River Spercheios valley and delta, included among the aquatic resources and sensitive ecosystems of Phthiotis Prefecture. The purpose of the present research is to highlight the main anthropogenic pressures and interventions in recent decades in the aquatic resources and sensitive ecosystems, evaluate the impact-changes on the natural environment of the research areas, and to propose some ecological restoration proposals and monitoring.
For the depiction of the environmental situation and for the assessment of the environmental impact caused by certain anthropogenic interventions on the aquatic resources and sensitive ecosystems of Phthiotis Prefecture, involved a series of different stages: the study of bibliographical references, systematic in situ observations (field-work), measurements using the Global Positioning System (GPS) satellite signals, observation and direct digitizing on the basis of different aged aerial photos and satellite images (Landsat, Google Earth). The “in situ” observations were conducted, at least, every 5 years during the months of April, July, October and January for the years 1996, 2001, 2006, 2011 and 2016, in selected places of each aquatic resource and sensitive ecosystem under study. Data were analyzed quantitative and qualitative, while apposite thematic checklists and tables were created.
The environmental destabilization of most of the wetlands in the area under study, is mainly caused by certain anthropogenic pressures and interventions which alter “critical” parameters of the environment, leading to wetland alteration or degradation and have a significant impact/changes on: a. Flora and local natural ecosystems, b. Landscape, c. Surface and underground waters and c. Geomorphology.
About half of the people that live in developing countries do not have access to safe drinking water and 73% have no sanitation, thus some of their wastes contaminate their drinking water supply leading to a high level of suffering. In view of the foregoing, this study was carried out in two suburbs in Benin City, Edo state Nigeria in order to examine the hydrogeology and water quality of these communities. Three boreholes were drilled to the depth of 57.60, 60.35 and 45.68 meters respectively while soil samples were taken at 4.57 meter intervals in order to determine the soil properties, aquifer geometry and subsurface geology. Water samples from these wells were collected including two other existing boreholes and a sample from a nearby river in order to evaluate the water quality, using water quality index (WQI). The water samples were analysed for physico-chemical parameters such as TDS, pH, TH, EC, NO3-, SO42-, Cl-, Mg2+ using standard laboratory procedures while the heavy metals were analysed using Atomic Absorption Spectrometer (AAS) model 969 unicam series with air acetylene flame.The results obtained from physico-chemical analysis were used to compute the values for water quality index and the results revealed that three of the wells were extremely contaminated, two were of good quality and the other poor. The hydrogeological study revealed that the aquifer geometry is unconfined basically of fine to coarse sands grains with high porosity and permeability which enhance water percolation. The groundwater flows from North West towards South East; and it was observed that water quality increases from adjacent landfill towards the river in the study area which suggest that the leachate emanating from the unprotected landfill coupled with the geography and geology of the terrain is a major factor contributing to the poor water quality. The authors advise a proper legislature and enforcement of existing environmental laws to arrest the situation.
This paper aims to find out the regional pattern of hypsometric curve (HC) and hypsometric integral (HI) over the Kushkarani river basin, a Chhottanagpur plateau fringe low relief basin. The paper also attempted to know how far different driving factors control HI. From the result is it found that most of the curves are slightly concave and HI value ranges from 0.35 to 0.55 for the selected sub basins. So, basins are now experiencing mature stage of geomorphic evolution. Such stage will create an equilibrium condition of erosion and transportaion. Fluvial process is mighter than hill slope process. Analysis of the impact of shape, size, hierarchy, elevation, geology, soil erosion, tectonic intensity etc. on HI do not highlight any significant result. Hypsometry of this basin is scale independent as scale effect is almost neglibible. Tectonic influece is not prominent over the basin as indicated by the HI in reference to tectonic index map. Predicted soil erosion is not also high over the areas where HI is high.
Sedimentary facies description and sedimentology of parts of the Coastal Swamp Depobelt have been studied using well logs and core data. Five wells designated FABI 001, 002, 003, 004, and 005 were correlated to establish the lateral continuity of the H7000 sand across the field, and using gamma ray log to corroborate the gross depositional environments of the cored interval. About 51 ft of cored section of well 001 was described to identify lithology and delineate depositional environments based on facies types and sedimentary structures. The results of the analysis showed that the H7000 sand occurred between 12750 and 13500 ft (in well 001) across the five wells at different stratigraphic positions. The sand unit (cored interval) displayed a funnel shape log trend occurring in two prograding parasequences. The upper parasequence is well serrated whereas the lower unit below 13060 ft has little or no serration. Five facies types identified based on sedimentary structures, lithology, and paleontologic content include; cross-bedded sandstone, bioturbated cross-bedded sandstone, bioturbated interbedded sandstone and mudstone, bioturbated heterolithic sandstone/siltstone, and silty mudstone facies. Four environments inferred based on facies description include; tidal channel, upper shoreface, lower shoreface, and proximal shelf mudstone. Each facies unit was identified based on lithology and sedimentary structures of the core sample, textural characteristics and gamma ray log trend. The Tidal channel facies displays a fining upward log trend and overlies the upper shoreface facies. Upper shoreface facies is characterized by trough cross bedding, planar cross bedding, alternating parallel cross bedding, and double mud drape. The sandstone is light grey to light brown in colour, fine to medium grained, well sorted, rare hummocky laminations and free of shale successions; whereas lower shoreface is characterized by interbedded sandstone/mudstone facies. The offshore mudstone interval is composed of siltstone and very fine-grained sandstone showing parallel laminations, wavy and current ripple cross-laminations. This examination provided the framework for suggesting that the FABI field sediments were deposited within the shoreface shallow marine systems where both tide and wave activity influence the deposition of sediments.