Depletion of Forested Area: Geidam Perspective (Published)
Land cover maps provide best understanding of current landscape change over time. One can evaluate past land cover maps for several different years for management decisions as well as gain insight into the possible effects on decisions making. One of the key monitoring areas is how the environment keeps degrading resulting from increased anthropogenic activities such as the removal of the forest covers. This study monitors the pattern changes of the Geidam Yobe state Nigeria, using Landsat images of two different periods from Enhanced Thematic Mapper (ETM+) image of data of 1988 and 2018. The images were geometrically and atmospherically pre-processed then classified, using maximum likelihood (MLC) algorithm to produce land cover maps of the Geidam. The accuracy of the classification was assessed with confusion matrices giving results morethan the minimum 85% required. The results revealed that the built-up and tree area increase by (+30.97%), water body reduced by (-5.06%) and forest reduce by (-23.48%) within the study period. This shows a rapid decrease in the forest, which is partly attributed to deforestation activities and partly to climate change impact.
Citation: Alhaji, Mustapha Isa; Ayuba, Abubakar Fusami, and Danboyi, Joseph Amusu (2022) Depletion of Forested Area: Geidam Perspective, British Journal of Earth Sciences Research , Vol.10, No.4, pp.1-,6
Analysis of Land Use Changes Using Remote Sensing and GIS Tools in the Peri Urban Ecosystems of Dar es Salaam (Published)
Land use changes in peri urban areas have resulted from urban expansion and have attracted many researchers during the last two decades. In this paper, urban expansion and their spatial growth patterns of the Dar es Salaam City has been studied over a period of 30 years (1980-2010) through statistical classification approaches based on the remotely sensed images obtained from sensors both Landsat TM5 and SPOT4. The research method included, mapping of land use changes using multi-temporal images, land use/land cover change as detected by applying remote sensing tools. Thereafter, based on the results of image classification, the analysis of land use/land cover changes was made. A model of urban expansion is also analysed by applying diverse technologies of the GIS. Research shows that land use/land cover change detection using remote sensing and GIS are good means of research of urban expansion. In addition, times series data of land use/land cover changes reveal temporal spatial change useful in determining timely planning intervention. Moreover, the analysis of the ecosystems and general urban expansion as established by land use/land cover changes in meticulous areas can be carried out. It is recommended that the national land related policies are reflective of these findings.
This study examined the integration of Remote Sensing and Geographic Information System (RS/GIS) for analyzing land use and land cover dynamics in Gombe Metropolitan, the Gombe State capital for the period 1976 to 2016. Land sat (TM) images of 1976, 1996and 2016 were used. The study employed supervised digital image classification method using Erdas Imagine 9.2 and Arc GIS 10.5 software and classified the land use into undisturbed vegetation, sparse vegetation, Settlements, Farmlands, Rock outcrops, Bare surfaces. The images were analyzed via georeferencing, image enhancement, image resampling and classification. The results obtained showan increasing settlements (from 0.36% – 4.01%) and farmlands (from 24.8% – 51.2%), over a decreasing of other LULC classes (bare surfaces, undisturbed and sparse vegetation, and rocky outcrops) for the time period of 1976 to 2016. These results could help city planners and policy makers to attain and sustain future urban development. It is therefore recommended that encouragement should be given to people to build towards the outskirts, like New mile 3 and Tumfure,etc through the provision of incentives and forces of attraction that is available at the city center in these areas to avoid the problem of overcrowdings.
The Effect of Diminishing Urban Green Spaces on Environmental Quality in Kisumu City (Published)
Green spaces contribute to aesthetics and environmental quality of life in urban areas. Kisumu City, the study area, has been experiencing demographic, environmental, economic, socio-spatial and institutional challenges leading to loss of green spaces. The main problem addressed by the study was dysfunctional use of green spaces leading to their loss, aesthetic value and low environmental quality. The study objective was to determine the effect of spatial change of urban green spaces on environmental quality. Data were both qualitative and quantitative and were collected through observation, interviews, questionnaires, photography, remote sensing and Geographic Positioning System (GPS). Qualitative research focused on site-specific analysis of urban and peri-urban neighbourhoods in Milimani and Nyalenda, respectively, which were purposively sampled. Results showed that area under green in 2005 was 44.8% while in 2004 it was 24.87% showing a decrease of 55.5%. However, in 2010, there was a temporary increase of green space of 51.82% due to demolitions to pave way for road expansion leading to decrease in carbon sink, resulting in increase in carbon footprint. This has led to low environmental quality. The study projects that by the year 2030, without proper planning interventions, the city will lose all its urban green cover. The research recommends the use of remote sensing for creating land-use inventory and monitoring systems. Citizen involvement in planning and management of urban green spaces is recommended because this will transform ecotourism in Kisumu City.
Object-based methods for image analysis have the advantage of incorporating spatial context and mutual relationships between objects. Few studies have explored the application of object-based approaches to forest classification. This paper introduced an object based method to SPOT5 image to map the land cover in Yen Nhan commune in 2015. This approach applied multi-resolution segmentation algorithm of eCognition Developer and an object based classification framework. In addition, forest maps from 2000 to 2015 were used to analyze the change in forest cover in each 5 years period. The object based method clearly discriminated the different land cover classes in Yen Nhan. The overall kappa value was 0.73 was achieved. The estimation of forest area was 89.05 % of forest cover in 2015. By overlaying achieve forest maps of 2000, 2005, 2010 and the classified map of 2015 shows vegetation changed during 2000-2015 remarkably.
Change Detection in Landuse / Landcover Mapping in Asaba, Niger Delta B/W 1996 And 2015. A Remote Sensing and GIS Approach (Published)
Remote sensing is used in this research work for the development and acquisition of Landuse/land cover data, pattern and its attendant effects in Asaba, Delta State Nigeria. Remote sensing images and digital data verified by ground trothing (field work) satellite data are used to assess the rate of change in Landuse / Land cover between 1996 and 2015. It also examines the extent to which images and GIS softwares effectively contribute to mapping landuse/cover in the Niger Delta region. Remote sensing and geographic Information System (GIS) help integrate natural, cultural, social and economic information to create spatial information system on the available terrain resources. Sets of NARSDA images were acquired corresponding with the years, field checked to ascertain the data captured on the terrain.. The digital satellite data are incorporated as input data into IDRISI 32 GIS environmental to separately map out the landuse/land cover units and their magnitude determine. Five distinct units were identified in classification of landuse/landed cover pattern categories as follows: Farmland, Build up land, Waste land, Forest land and Water bodies. Land consumption rate indicate a progressive spatial expansion of the city was high in 1996/2006 and higher between 2006 and 2015. Also, land absorption coefficient being a measure of consumption of new urban land by increased urban population, was high between 1996 and 2006 and between 2006 and 2015. Ground trothing was carried out to ascertain the accuracy of data and there are major changes in the landuse/land cover. It was discovered that there is rapid inbuilt-up areas evidently explained in buildings projects that resulted in decrease in forest land, agricultural land and open space. This is attributed to the anthropogenic activities of farming, bush burning, grazing, etc. However, the area occupied by water remained unchanged over the years. This study demonstrates that remotely sensed data and GIS based approach is found to be timely and cost effective than the conventional method of analysis, classification of land use pattern effective for planning and management