The dynamics of urban expansion and land use/land cover changes using remote sensing and spatial metrics: the case of Mekelle City of northern Ethiopia

Abstract

Information on the rate and pattern of urban expansion is required by urban planners to devise proper urban planning and management policy directions. This study evaluated the dynamics and spatial pattern of Mekelle City's expansion in the past three decades . Multi-temporal Landsat images and Maximum Likelihood Classifier were used to produce decadal land use/land cover (LULC) maps. Changes in LULC and spatial pattern of urban expansion were analysed by post-classification change detection and spatial metrics, respectively. The results showed that in the periods 1984-1994, 1994-2004, and 2004-2014, the built-up area increased annually by 10%, 9%, and 8%, respectively; with an average annual increment of 19% (100 ha year −1 ), from 531 ha in 1984 to 3524 ha in 2014. Between 1984 and 2014, about 88% of the gain in built-up area was from conversion of agricultural lands, which decreased by 39%. Extension of existing urban areas was the dominant growth type, which accounted for 54%, 75%, and 81% of the total new development during 1984-1994, 1994-2004, and 2004-2014, respectively. The spatial metrics analyses revealed urban sprawl, with increased heterogeneity and gradual dispersion in the outskirts of the city. The per capita land consumption rate (ha per person) increased from 0.009 in 1984 to 0.014 in 2014, indicating low density urban growth. Based on the prediction result, the current (2014) built-up area will double by 2035, and this is likely to have multiple socioeconomic and environmental consequences unless sustainable urban planning and development policies are devised.

Is Nigeria losing its natural vegetation and landscape? Assessing the landuse-landcover change trajectories and effects in Onitsha using remote sensing and GIS

“…And these tools have prompted accurate information on LULC change and have effectively supported many recent studies on change detection [9][10][11][12].…”

“…The government, the agriculturists and the urban planners have increased the number of housing units and facilities development, established more commercial towns, and expanded arable lands to satisfy the growing population. Many studies have been focused on modelling and detecting the LULC change without identifying the primary effects on plant species [9][10][11][12]. This study therefore aimed at assessing the effects of LULC change on natural resources especially vegetation and water between 1987 to 2015.…”

Urbanization in Small Cities and Their Significant Implications on Landscape Structures: The Case in Ethiopia

“…However, most of these studies have concentrated on large metropolitan regions due to their significant influences on socio-economic and environmental conditions [14,16]. In contrast, the smaller cities and towns, where scattered urban growth is more prominent [17][18][19], have been given little attention [20][21][22]. As a result, the conceptual ideas regarding urbanization have been primarily influenced by the studies in large cities.…”

“…Since the past couple of decades, regional cities in Ethiopia have grown faster than the capital city, Addis Ababa [43]. This feature can likely be explained considering the national economic development [44] and urban improvement policies [45] that fostered the rapid urban expansion in secondary and tertiary cities.Some studies have explored urban expansion in Ethiopia [15,19,42,46,47], primarily focusing on the analysis of urban growth and urban land changes in the regional or capital cities. However, the literature on the trend of urban spatial growth and its influences on other natural landscape configurations is quite limited with regards to small cities and towns.…”

“…Some studies have explored urban expansion in Ethiopia [15,19,42,46,47], primarily focusing on the analysis of urban growth and urban land changes in the regional or capital cities. However, the literature on the trend of urban spatial growth and its influences on other natural landscape configurations is quite limited with regards to small cities and towns.…”