Assessment of Anthropogenic Activities and Their Impact on Ngong Hills Forest in Kajiado County, Kenya: A Remote Sensing Approach (Published)
Human beings are dependent on forests for various livelihood needs. Forests offer a variety of benefits, including ecological, social as well as economic benefits. As such, the development and conservation of forests around the world is vital. Monitoring of the forest ecosystem is mandatory in order to detect any changes in the ecosystem. Forest cover change detection gives an opportunity to track the productivity, health and the forest cover as well over the years so as to enable proper management, promote conservation and enhance functionality. Optical and radar remote sensors make it possible to monitor changes by use of various analytical techniques that include visual interpretations. The study investigated how remote sensing can be applied to detect change in forest ecosystem and to assess the rate of change of Ngong Hills Forest in Kenya. The project sought to determine whether anthropogenic activities are the major cause of the change in Ngong Hills Forest. Data from satellite images was analysed from 1984 to 2019 to identify the changes that have occurred on the ecosystem. Landsat and Rapid-Eye images were used to inform on change detection. In this case, rapid eye data was found to be better than Landsat data in informing on change detection because of its high resolution thus high precision and better results. The changes depicted by the remotely sensed data were mapped for ease of analysis and visualization. The research depicted a massive decrease in the forest cover despite the afforestation efforts by the Kenya Forest Service (KFS) in the 1990s. The forest has been depreciating massively from 1995 depicting greater deforestation rates between the years 2010 and 2019. This depreciation has been acknowledged by the KFS as it is said to be occurring due to the anthropogenic activities mainly settlement and logging. The means of detecting change by use of remote sensing is thus able to identify the exact areas that change has occurred and thus provide insight for the Kenya Forest Service and other ecosystem protection bodies on the most affected areas and the extent of change. Once the study area is mapped, it is possible to calculate the areas that have decreased in vegetation quantity, areas where increase has occurred as well as the areas that have remained unchanged. The findings of the study make it possible for management agencies to enforce conservation because of the presence of reliable data.
Physicochemical and Microbiological Characteristics of Water Samples from the Borgu Sector of Kainji Lake National Park, Nigeria (Published)
The quality of water resources in any ecosystem provides significant information about the available resources for supporting life in such ecosystem. The study therefore assessed the physicochemical and microbiological characteristics of water samples from the Borgu Sector of Kainji Lake National Park, Nigeria. The study was carried out at Borgu sector of KLNP purposively selected based on the availability of perennial waterholes. Water samples were collected from four waterholes for two seasons (dry and wet). Water samples were subjected to physicochemical [temperature, pH, total dissolved solid, electrical conductivity, total suspended solids, dissolved oxygen (DO), nitrate, chloride, phosphate, sulphate, biological oxygen demand and chemical oxygen demand (COD)] and microbiological (total coliform and fungal counts) analyses using standard methods. Data collected were subjected to descriptive statistics and T-test at α0.05 and compared with WHO permissible limits. The result showed that DO and COD levels of all the water samples were above the WHO guideline while there were significant seasonal variation in the values of temperature (t=4.93), EC (t=2.46), TDS (t=2.33), nitrate (t=3.66), chloride (t=4.91) and COD (t=4.23) in the waters sampled across the seasons of sampling. Salmonella / Shigella and Staphylococcus aureus were observed to be absent while the total coliform and fungi counts were observed to be higher than the WHO permissible limit for drinking water. The presence of thermo-tolerant such as Klebsiella sp and Enterobacter sp observed in the study may be an indication of faecal contamination. Periodical monitoring of the river water quality in Kainji Lake National Park is required to protect drinking water resources, encourage recreational activities and provide a good enabling environment for wildlife.
Impact of Anthropogenic Activities on the Quality of Shallow Groundwater of the Chad Basin in Maiduguri, Nigeria (Published)
This study examined the effects of anthropogenic activities on the quality of shallow groundwater of the Chad Basin in Maiduguri, Nigeria by analyzing samples from 46 boreholes with a range of 40 m – 115 m, and an average depth of 60.54 m. The result of the analysis showed groundwater to be polluted in many boreholes. The pollution results from increased anthropogenic activities such as waste disposal, pit latrines and agricultural activities. About 22% of the sampled boreholes complied with the separation distances stipulated by the Federal Ministry of Water Resources and the Environmental Protection Agency leaving a whopping 78% in contravention of the minimum separation distance. Major point pollution sources identified include soakaways, pit latrines, solid and liquid wastes, plant and animal waste products and mechanical workshops. Turbidity, total dissolved solids (TDS), Fe, Cr, Cu, Mn and PO4 are physicochemical parameters found to have exceeded the standard set by the Nigerian Standard for Drinking Water Quality. Seven wells had exceeded turbidity and TDS standards, 11 and 34 wells had exceeded the standards for Fe, Mn and PO4, and Cr and Cu respectively. Densely populated parts of the city have high TDS and turbidity values. To improve groundwater quality in the study area, the paper suggests enforcement of the minimum standard spacing for boreholes and pit latrines. Also, it suggests environmental education that will make the public to be aware of the necessity of ensuring environmental health which will ensure quality of groundwater and proper disposal of solid wastes.
Water samples were collected from seven different locations along the Aba River close to various human, industrial, commercial and domestic activities. The heavy metals were analyzed using the Atomic Absorption Spectrometer (AAS). The result revealed that the concentration of some heavy metals like Iron, Copper, Manganese and Chromium are above the WHO and FMEnv Standard limits for surface water. These high values could be attributed to indiscriminate disposal of wastes into the river. The various parameters of the water samples from the control site (Okpu-Umuobu) were significantly different from those of locations close to the major industrial/commercial activities. This confirms the impact of human activities on the quality of the Aba River. The impacts of dredging and sand mining in and along the river bank were obvious. These activities have an adverse effect on the environment and ecology, speeding up flow and potentially increasing the risk of flooding downstream. This also has the potential to damage ecology by directly affecting its physical habitat, disrupting riverine processes and reduced connectivity with the floodplain. It is therefore recommended that effluent treatment plants be installed to treat waste generated before they are discharged into the stream as well as regular monitoring of the River should be encouraged by the regulatory bodies.