This paper investigates how human activities have influenced and altered land cover. It also indicates that the nature of cultural substitution of the indigenous forest species have significance for the functioning of the earth system. It therefore attempts to quantify the ecological implication of land cover change consequent upon land use. The paper integrated a topographical map of 1969 and satellite imageries from Landsat MSS 1972, and Landsat TM 1991 and 2000 with ground truthing and socio-economic surveys to assess changes in forest resource use and land cover in south-western Nigeria. The study argues that land cover modification and conversion is directly related to loss of biodiversity and has negative effect on the ecological setting and that there is need to develop more environmentally and socially equitable approaches to forest management.

The study evaluated the climatic and societal implications of vegetation
degradation in Okomu and Gilli-Gilli Forest Reserves (OGFRs) of Nigeria. Both remote sensing
and non-remote sensing data and methodologies were used. Landsat data between 1984 and
2011 were used as quantitative data while social survey was carried out for qualitative data
collection and assessment. Both remote sensing classification and Normalized Difference
Vegetation Index (NDVI) methods were used in this study. The results show that deforestation
resulting from farmland encroachment has increased in Okomu Forest Reserves (OFR) but was
relatively low in Gilli-Gilli Forest Reserves (GFR). In 1984, about 17 % of the reserves were
deforested, and this increased to 37 % in 2011 in OFR. These values reveal a massive
deforestation. Forest disturbance within the GFR is much less than OFR possibly because high
rate of illegal oil palm development in OFR. The result shows no significant impacts of
vegetation degradation on local climate, but people in the communities around the reserves
reported several climatic extreme events as a result of vegetation removal. However, the study
could not reveal direct significant impact of vegetation degradation on local climate but there
were rather indirect impacts from climate events. The results from social survey show that over
80 % of local people perceived high rate of heavy erosion and flooding mostly from year 2000 to
2011. It is obvious from the social survey that unrestrained felling of forest in the region has
also rendered the soil vulnerable to erosion and flooding since forests tend to reduce the impact
of erosion and floods. There is a need for proper enforcement of forest conservation laws in order
to reduce the rate of deforestation, not only in OFR and OGR but also in all forest reserves in
the country.

This article presents a new numerical scheme to approximate the solution of one-dimensional telegraph equations. With the use of Laplace transform technique, a new form of trial function from the original equation is obtained. The unknown coefficients in the trial functions are determined using collocation method. The efficiency of the new scheme is demonstrated with examples and the approximations are in excellent agreement with the analytical solutions. This method produced better approximations than the ones produced with the standard weighted residual methods.

This paper presents an efficient numerical method for the approximate solution of problems involving boundary condition at infinity. The whole idea of the method is based on the combination of Laplace transformation method and weighted residual method. Numerical examples are given to show the validity and applicability of the proposed method and the results obtained are compared with other methods in the literatures.

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