Introduction
The rapid modification of Land Use and Land Cover (LULC) by human activities are well recognized worldwide. The rapid population growth, urbanization and economic development have significantly altered the Earth’s terrestrial surface processes, which causes undesirable impacts on environmental attributes at a local, regional and global level (Verburg and Overmars, 2007). The monitoring regarding land use land cover change has become a fundamental component in recent strategies for managing natural resources (Lambin, Geist, and Lepers, 2003). In recent decades, LULC change studies has emerged as an important research question due to abrupt LULC changes which are responsible for natural landscape modification worldwide (Xiao et al., 2006). Though it is possible to detect and monitoring LULC by traditional surveys and inventories, however, Geographical Information System (GIS) and Remote Sensing (RS) techniques are more advantageous in terms of temporal, time saving and cost effectiveness, as well as future monitoring of LULC (Yuan et al ., 2005). It is very important to have historical, persistent and accurate data on LULC of the earth’ surface for sustainable development program in which LULC work as one of the main input criteria (Elkawy et al ., 2010).
The land cover change detection and monitoring by various disciplines found that LULC has diverse applications such as ecology, environment, hydrology, forestry and geology. Urban landscape change is a major concern for eco-friendly and sustainable development for the economic growth of any area. The abrupt urban LULC such as unregulated development, loss of agriculture lands, soil erosion, deforestation, damage of wildlife habitat and pollution are very harmful for the environment (Weng, 2001; Hassan et al., 2016). Urbanization and urban sprawl is one of the main causes, which re altering the land cover of the earth’s surface. The process of urban complex is determined by the interactions of environmental and human factors in different spatio-temporal scale. In the past decades, urban sprawl has been studied widely due to the increasing interest in environmental issues and challenges (He et al ., 2006; Kamh et al., 2012).
Sporadic development of urban inhabitants and its footprint on the urban environment has been widely reported. Urban expansion can lead significant environmental modification as main ecosystem services, such as availability of water, food, raw material, natural vegetation and landscape beauty, may degrade as a result of rapid growth of urban areas (Sieber and Pons, 2015; Manzoor et al., 2018). Studies indicates the effects of unplanned urban growth on ecosystem services and to incorporate the evaluations into urban management plans. For instance, environmental carrying capacity of a landscape can be assessed by its ecological footprint and bio-capacity, and identified whether a given development activities is consistent with particular environmental targets, hence assisting to develop environmental sustainable spatial plan for future urban expansion (Świąder, Szewrański and Kazak, 2018; De Jung et al., 2018). It is essential to identify Ecosystem Services Bundles (ESB) and socio-cultural preferences in urban landscape development where human-environmental relations creates desirable or undesirable ecosystem services (Raudsepp-Hearne, Peterson and Bennett, 2010; Spake et al., 2017).
The world’s most populous cities are located in developing countries, therefore, rapid and unplanned urban expansion produces server impacts on ecosystem services and facing difficulties and challenges in urban landscape management. Although, in developed countries consequences of rapid urban expansion are repeatedly documented (Jafari et al.,2016). LULC studies in developing countries like Pakistan, remain scant. In South Asia, Pakistan is a fastest urban growing country, the process of urbanization increased due to rapid population growth as well as industrial expansion, economic and social activities and intensive use of land resources. In Pakistan the annual growth rate of urban population is nearly 2.5 percent (Shaikh and Ijaz, 2018). In the last two decades, Punjab province of Pakistan has experienced rapid population growth and economic development accelerated the process of urbanization and caused extensive deforestation, agricultural land to build up area and environmental degradation (Lee et al ., 2017, Pakistan Bureau of Statistics, 2018). The country has cover only 3% of forest whereas government aimed at 7% forest by 2015 which has not been achieved yet; forest cover of 20-25% is needed for a stabled economy (Manzoor et al., 2018; Zizinga et al ., 2018). Recently, China-Pakistan Economic Corridor (CPEC) project is likely to have impacts on socioeconomic conditions of the provinces
Not many studies on LULC changes have been conducted in urban areas of Pakistan and for Islamabad in particular. For example, Hassan et al . (2016) conducted a study using GIS and remote sensing methods at capital Islamabad area. They observed increase in agriculture area, build up area and water bodies from 1992 to 2012. Samie et al . (2017) scenario based analysis indicated that cultivable and build up land would expand, the findings mentioned sustainable land use planning and management in Punjab province is essential. Therefore, regular and up-to-date data on urban sprawl is needed for urban planning, land use management and for proper distribution of services and infrastructure within the urban area. Islamabad city is a functional city, rapid LULC change due to population growth, economic development and climate change resulted in wide range of environmental impacts, including degraded habitat quality (Hassan et al., 2016). While remote sensing technology has been the main provider of cost-effective, high quality datasets for land surface management and monitoring in the past decades (Lunetta et al., 2002). Pakistan urban areas needs an appropriate interdisciplinary policy guideline and political wills to device a sustainable management and protection of forest, vegetation and ecological sensitive sites. In this context, the main objective of the study was to assess the nature, significance and rate of land cover change from 1979 to 2019 based on the analysis of satellite Imagery.