# I. Introduction hanges in the ecology of urban environment occasioned by increasing population, overcrowded habitations and uncontrolled exploitation of natural resources may have accounted for this wide ecological footprint of urban areas which is not peculiar to developing countries (Stoel, 1999 andHales, 2000). Hales,(2000), observed that the pace and scale of growth have outstripped the capacity to maintain acceptable standards of public health, environmental safety and sustainable economic growth in urban areas in less developed nations in Africa, Asia and Latin America. Undoubtedly, urbanization is a process that continuously initiates changes in land use. For any meaningful development to take place in an area there is the need for adequate information on the past and present land use patterns. Sufficient records on land and its uses are generally scanty in Nigeria (Abbas and Arigbede, 2011). This may be due to the tedious nature and cost of conducting ground surveys, and the bulky nature of data generated. The use of remote sensing and GIS techniques to capture data and process for safe keeping, management and regular updating, therefore, serves as a reliable alternative to the analogue methodology. Thus, the monitoring of land cover/land use (LCLU) using satellite imagery has been adequate for general extensive synoptic coverage of large areas (Lilles and, et al., 2004). As a result, this has reduced the need for expensive and time consuming ground surveys conducted for validation of data. One of the major problems arising from urbanization is thus vegetation degradation. It is a decline in the quantity and quality of the grasses, herbs and woody species found in an ecosystem (Douglas, 1994). Vegetation degradation as defined by Conacher and Sala, (1998), "is the temporary or permanent reduction in the density, structure, species composition or productivity of vegetation cover". Vegetation condition is the key aspect of degradation in grasslands, wood/forest lands and croplands. Thus, over exploitation and management practices may result in vegetation degradation and tend to enhance land degradation risk. Pressure on the natural vegetation has arisen from changing agricultural practice, fire and livestock grazing, and the feed-back with the loss of biodiversity. Natural land degradation develops because the sparse native vegetation and its inherently low productivity are not able to contribute the necessary organic matter that gives life to soil and binds soil particles. With this degeneration in soil quality, productivity falls, leading to reduction of vegetation. However, natural degradation of vegetation is typically gradual and often reversible (Michael, 2013). In contrast, man-induced destruction is mostly rapid with diminished time or chance to compensate for the loss. # II. Materials and Methods # a) Study Area The study area is Gombe town and, it is located on latitude 10 0 13'and 10 0 20 ' N and longitude 11 0 02'and 11 0 16'E. The study area is limited to the urban area and environs. Some 9km radius around the town has been arbitrarily demarcated for the study with Union Bank round about, along Biu Road being the centre point (Fig. 1).Gombe is located within the sub-Sahara climatic zone. It is characterized by two distinctive seasons, that is, dry season (November-April) and wet season (May-October). The rainfall here averages 907 mm. The vegetation of Gombe is within Sudan/Guinea savannah. This is characterized by shrubs and scattered trees with a different species of grasses. The predominant tree species include Locust bean tree, Baobab tree, Tamarin, Moringa, Date-palm, Neem trees and Azadirachtaindica. The soils are highly ferruginous, formed as a result of intensive weathering of the basement rocks. Both primary and secondary data was employed in this work. Socio-economic data and information on the status of tree species were gathered through questionnaire survey that involved 195 respondents using purposive sampling techniques the study area. The remote sensing and the geographic information system (GIS) technology and applications were applied in the determination of the land cover changes. The interpretation and classification of satellite images involved subsetting and other pre-processing steps including geo referencing, colour composite and unsupervised classification; ground truthing, screen digitization of some features, supervised classification and change detection. Subsetting consisted mainly in selecting and extracting the study area from the full scene images. Colour composite and unsupervised classification enabled us to establish major land cover classes before ground truthing to match the reality in the field with the classified image. After ground truthing, the supervised classification enabled to proceed on land cover map composition for each image. # c) Data Analysis The obtained result was analyzed using tables, charts and maps. The size and area of the land cover changes were calculated and represented in hectares. The rationale for these was based on the total size of the study area. # III. Results and Discussion # a) Socio-Economic Characteristics of Respondents Table 1 shows the distribution of respondents by age, sex, educational level and level of income. As presented in Table 1, majority of the respondents that responded to the questionnaires constitute 67% males and 33% females. The data on Table 1 also indicates that majority of the respondents are between the ages of 21-30 years which is 44%, those in ages between 31 -40 years, 37%, 41-50 years constituted only 8% while those above 51 years accounted for 11% respectively. The distribution of respondents by educational level reveals that, 12% have attained primary school education, 28% secondary school education, and 49% tertiary education while 11% have no formal education. The result reveals that most of the respondents are literate which cut across different educational backgrounds. The occupation of the respondents indicates that 37% of them are civil servants and 33% constituted the traders/ business person. This two categories were the highest and simply be due to the fact that the study was carried out within the metropolis where majority of the people are either government works or businessmen. The farmers constituted only 14% which can only explain the fact that due to urbanization, fertile land for agriculture is hardly found. # b) Vegetation Cover Characteristics The study sought to identify dominant species found in the study area, in all 12 tree species were identified belonging to 9 families as shown in the Table 2. The Fabeceae family has the largest number of species. The woody vegetation was hardly found in the study area as a result of urbanization and infrastructural development. The few species found were mostly planted by house owners as shades and wind breakers. Also, around the Gombe State University and Old GRA, trees such as date palm, neem tree, mahogany were dominant. The trees in the area present significant importance almost in all human endeavors. A large percentage of the trees in the area have their advantage which made them of great use and advantage to the people of the area. Almost every tree or shrub has one or more uses that attract people's attention to put proper care on such plants. Table 3 below shows the status of the woody species, reasons for the vegetal loss and the challenges experienced when urbanization takes place at the detriment of vegetation cover. The status of the woody species indicates that the area is majorly composed of sparse vegetation constituting about 56% while moderate and abundant vegetation constitutes only 30% and 5% respectively. The major reasons for these were attributed to urban development (64%) as seen in Figure 2 and closely followed by cutting the trees for fuelwood (19%) and agricultural expansion (16%). Despite the fact that the study area is in the centre of the town, people who purchase parcels of land for development and find trees within it cut them and either sell or use for their consumption. Likewise, as the economic situation is telling on the people, they tend to clear any available land or space within their environs for cultivation and livestock rearing. The challenges experienced due to urbanization were majorly flooding and erosion which constituted 53% and this is due to cutting down of trees which has made the environment prone to this hazards. # Reasons for Tree Loss in the Area # IV. Land use Land Cover Variation As shown in Figure 3, the land-use/land-cover distribution clearly indicate, that there is considerable variation in the land use/land cover of the studied area over the examined period. There is however no consistent variation in the area coverage of the different land uses over time. The only exception is the built-up area that showed a consistent increase over time. The bare surfaces covered about 11% in 1976then increased to about 13% in 1996 and increased again to 17% in 2016. This may be attributed to the fact that open spaces can easily be used for urban development. In a similar fashion, the area covered by vegetation decreased from 62% in 1976 to 27% in 1996 then decreased again to 11% in 2016. The farmland increased from 25% in 1976 to 43% in 1996 and decreased to17% in 2016.This was as a result of the conversion of farmlands to infrastructures. By contrast, the settlements increased from 2% in 1976 to 15% in 1996 and subsequently to 51% in 2016. So also, the rock outcrop increased from 0.36% in 1976 to 10% in 2016. # V. Conclusion Attempt was made to capture as accurate as possible six land use land cover classes as they changed through time. The six classes were distinctly produced for each study year but with more emphasis on vegetation as it is affected by a combination of natural and anthropogenic activities and indeed, it is one that affects the other classes. The result of the work shows a rapid decrease on the vegetation and a gradual increase in settlements between 1976 and2016 due to the fact that Gombe metropolis became the capital of Gombe state in 1996. As a result there was an influx of people from other part of the state and the country mounting pressure on the land for development purposes. Since then the area had been growing spatially to the detriment of other land cover types especially vegetation and agricultural land. Thus, the study aimed at assessing the impact of urbanization on vegetation cover in the Gombe town and its environs. Using maximum likelihood classifier, it was found out that the settlement increased steadily over the years at the detriment of vegetation and agricultural land that decrease rapidly from 1976 to 2016. The status of the woody species indicates that the area is majorly composed of sparse vegetation constituting about 56% while moderate and abundant vegetation constitutes only 30% and 5% respectively.The study also sought to identify dominant species found in the study area, in all 12 tree species were identified belonging to 9 families. The Fabeceae family had the largest number of species. The study has shown that the vegetation of Gombe state is undergoing degradation at an unsustainable rate which may likely disrupt the ecological functioning of the ecosystem in the state. Therefore, the study recommends that urgent attention on conservation of remaining vegetal resources in order to preserve the valuable assets of flora and fauna which are indigenous to the area. This can be done by insuring strict compliance with rules and regulations guiding conservation in the region and Nigeria as a whole also efforts should also be geared towards enlighten of the communities on the benefits of vegetation and the need for conservation in the ecosystem. 1![Figure 1: The Study Area b) Procedure for Data CollectionBoth primary and secondary data was employed in this work. Socio-economic data and information on the status of tree species were gathered through questionnaire survey that involved 195 respondents using purposive sampling techniques the study area.The remote sensing and the geographic information system (GIS) technology and applications were applied in the determination of the land cover changes. The interpretation and classification of satellite images involved subsetting and other pre-processing steps including geo referencing, colour composite and unsupervised classification; ground truthing, screen digitization of some features, supervised classification and change detection. Subsetting consisted mainly in selecting and extracting the study area from the full scene images. Colour composite and unsupervised classification enabled us to establish major land cover](image-2.png "Figure 1 :") 1Socio-economic attributesSexFrequency%Male13167.2Female6432.8Total195100Age (years)21-308644.131-407337.441-50157.7>512110.8Total195100Educational levelNo formal education2110.8Primary education2412.3Secondary education5427.7Tertiary education9649.2Total195100Occupation of the respondentsCivil servant7236.9Trader/business person6432.8Farmer2814.4Others3115.9Total195100Source:Fieldwork, 2017 2Impact of Urbanization on Vegetation Cover in Gombe Metropolis and EnvironsYear 201945Volume XIX Issue II Version I( B )i.S/N Distribution of Tree Species. Scientific NamesFamily NamesLocal NamesCommon Names-Global Journal of Human Social Science1AdansoniadigitataBombacaceaeKukaBaobab2AzardirachtaindicaFabeceaeDogonyaroNeem3BalanitesaegyptiacaBalanitiaceaeAduwaDesert date4FicusplatyphyllaMoraceaeGamjiFig tree5GrewiamollisTiliaceae (Malvaceae)DargazaApple ring acacia6HyphaenethebaicaArecaceae (Palmae)GoribaDoum palm7KhayasenegalensisMeliaceaeMadaciMahogany8PakiabiglobosaFabeceaeDoruwaLocust beans9Prosopis AfricanaFabeceaeKiryaIron tree© 2019 Global Journals 3Status of the woody speciesAbundant105.1Moderate5829.7Sparse11056.4None178.7Total195100Reasons for vegetation cover lossCutting of tree branches for grazing/fencing3015.4Agricultural expansion3216.4Fuelwood3618.5Urban development9548.7Others21.0Total195100Challenges experienced due tourbanizationFlooding2211.3Erosion6231.8Flooding and Erosion10453.3None42.1Others31.5Total195100Source: Fieldwork * Sustainable land management in Zaria using Remote Sensing and GIS techniques IAbbas YAArigbede Journal of Ecology and the Natural Environment 3 4 2011 * Land use and deforestation in the rainforest of South-eastern Nigeria FEBisong 2007. 1972-2001 * Nigerian Geographical Journal 5 1 * Analysis of Land use Land cover changes of Aba Urban Using medium Resolution Satellite imageries: Bridging the gap between cultures Marrakech NChigbu JIgbokwe KOrisakwe 2011 Morocco * The main problems of land degradation: their nature extent and severity. 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