ABSTRACT

The study on Evaluation of the Status and Sustainability Measures of Urban Forestry. A Case Study of Aba, Ohafia and Umuahia metropolis in Abia State, Nigeria was undertaken, using the Geographical Information System (GIS) and Remote Sensing technologies. ArchGIS 10.2 Software, with spatial resolution of 30 metres was purchased for a period spanning 1985 to 2015 (30 years). It was used for the image analysis. The landsat imageries for the various years were landed into the Archmap, with the image clipped to the study areas of Aba, Ohafia and Umuahia, which measured 2.0x2.0 km respectively, using control point generated from the field. The Satellite Imageries were analyzed, using the change detection technology. The analysis showed that the Normalized Difference Vegetation Index (NDIV) classified the study areas of Aba, Ohafia and Umuahia into vegetation and built-up areas, measured in landcover/landuse percentage and land size in hectares. From the results, in 1985, vegetation areas for Aba was (50.4%), Ohafia (77.2%) and Umuahia (64.2%) and in the same year, built-up areas were Aba (49.6%0), Ohafia (22.8%) and Umuahia (35.8%). For 1995 and 2005, there were progressive decrease of the vegetation areas, while the built-up areas continued to increase. In 2015, vegetation land areas for Aba, Ohafia and Umuahia were 37.8%, 47.6% and 48.3% respectively, while in the same year, the built-up areas increased to Aba (62.2%), Ohafia (52.4%) and Umuahia (51.7%). Ground truthing techniques was employed to verify the satellite imageries. The study revealed that there was steady decrease in the vegetation landcover of Aba, Ohafia and Umuahia metropolis in the year 1985 to 2015, while there was corresponding increase in built-up areas within the same period of study. Furthermore, structured questionnaires were administered to 300 respondents living within 2.0 km radius of the study areas of Aba, Ohafia and Umuahia. Data generated from the questionnaires were analyzed and discussed, using the relevant statistics. The study revealed that there were about forty plant species within the study areas, most of them were more than one metre and above in height. It was also observed that population growth and urbanization have led to loss in vegetation in the study areas of Aba, Ohafia and Umuahia. Based on these findings, the study recommended for aggressive public awareness and enlightenment programmes, reforestation techniques and general environmental education in Abia State.