Applications of Geospatial Techniques to Identify Landscape Changes and Urban Expansion of Dera Ghazi Khan City, South Punjab-Pakistan

A temporal analysis of landscape change patterns and consequent evaluation of urban expansion has been studied for the Dera Ghazi Khan city which is developing fast since 2000 as an emerging metropolis of South Punjab. The geospatial techniques particularly remote sensing augmented with GIS are vital tools and are mostly used in studying landscape changes and decision making for sustainable urban development. Four Landsat images (1991, 2001, 2011 and 2021) obtained from the free web of GLFC have been analysed. A supervised classification algorithm was applied to all images and results have been presented in both tabular and graphic forms. Present study, focuses upon two land-use classes i.e. built up and open areas, which will be monitored by land-use patterns of Dera Ghazi Khan city during 1991 to 2021 using satellite images. The graphical depiction of all the landscape changes, which have taken place in D. G. Khan city in the form of tables and maps provides detailed information about the degree and ratio of urban expansion and the changes in land use that occurred during the stipulated period.The classification was based on four categories i.e., urban land, bare soil, vegetation, and water; while maps were prepared to present the temporal changes in D. G. Khan city. A total of 52 sq./kms areas was selected for this study designated as the Dera Ghazi Khan city. According to the results, 33% of the urban area has been expanded in Dera Ghazi Khan from 1991 to 2021 and 19% vegetation cover has been reduced. It is a very alarming situation that agricultural land is decreasing because of urban expansion. The results revealed the significance of remote sensing and GIS in evaluating landscape changes

Assessing the Impact of Builtup Areas on Development of Urban Heat Island in Lahore, Pakistan

The aim of present study is to evaluate and assess the impact of built-up areas on development of the urbanheat island (UHI).The study mainly focused on Lahore, which is one of the mega cities of Pakistan. In terms ofpopulation size, Lahore is the second largest city of Pakistan with 11.13 million inhabitants. The geospatial techniques(Remote Sensing and Geographical Information System) along with statistical applications were applied to find out theLand Cover Land Uses changes and consequent development of builtup areas over the period of 2000 and 2015. Tostudy the UHI, the meteorological data of each 30 minutes for 36 days starting from 30th June 2015 to 4th August 2015were collected through direct on site observation by using digital weather station. The results of UHI were crosschecked by obtaining land surface temperature by using thermal infrared (TIR) band 6 of the Landsat-7 TM. The resultsshow that the LCLU and built environment have direct impact on development of UHI. The areas where there wasmore vegetation cover had less temperature while in urban areas, the temperature was measured higher. Over the periodof 36 days, the average UHI remained 5.5°C and the highest intensity of UHI was observed as 8.3°C thus augmentedresearch rationale. The study suggests establishment of a thick network of automatic weather stations in Lahore togauge the urban heat island intensity and to plant indigenous trees on vacant swaths and develop urban forest tomitigate city’s rising temperature

Connection between the South and East Asian Monsoons: Comparing Summer Monsoon Rainfall of Pakistan and South Korea

This study investigates the tele-connection of the southeast Asian monsoon systems by comparing the summer monsoon (June to September) rainfall variability between Pakistan and south Korea. The daily data sets (19812014) of rainfall of Pakistan and south Korea are utilized to explore the possible link. The data products of the National Centers for Environmental Prediction and National Center for Atmospheric Research (NCEP/NCAR) were also used for the understanding of the large-scale atmospheric environments. The patterns of summer monsoon rainfall on a daily basis between Pakistan and south Korea followed to each other throughout the year. Sub-seasonal differences of the summer monsoon revealed that July is the wettest month in both countries. The large-scale atmospheric environment of higher geopotential height revealed that the Tibetan high and the western north Pacific subtropical high are showing positive anomalies during positive phases over south Asia and east Asia, respectively. The anomalies of zonal wind are negative during positive phase and adverse in the negative phase between 20-40oN. The reduced westerly is interpreted as the seasonal variation and moving of jet streams from the east Asian route. The Tibetan high, northwestern Pacific subtropical high and the east Asian jet stream have reliable and sufficient linkage between the Pakistan and south Korea summer monsoon system

Seasonal and Regional Variations in Rainfall Distribution Over the Punjab-Pakistan

The purpose of present study is to investigate district and division wise annual rainfall variations over theprovince of Punjab, which is the largest in terms of population size as well important contributor in agricultural producein Pakistan. The results revealed that the rainfall trend has shifted from upper and lower Punjab towards the south,west, north and east respectively. The statistical analysis has inferred an overall increasing trend for the period 1990 to2000 and a decreasing trend during period 2001 to 2010 in Punjab province. The Z test value differences in the averagerainfall for each district level meteorological station have detected three increasing and two decreasing trends duringsummers of 1981-2015.The data revealed a significant changed seasonal trend observed in Murree and Sialkot(northern Punjab), Faisalabad and Lahore (central Punjab). Particularly, the changes have been observed in the southPunjab and over the central Punjab, while the same rainfall variations have shown a southward shift. The trend of therainfall had shifted in the Faisalabad division with the significant positive trend. In the Central Punjab, the positivetrend has also been found in all the districts. In the lower Punjab, Multan, Dera Ghazi Khan districts has shown anincreasing trend of rainfall. The findings are significant in changing agro-climatic zones in the Punjab and consequentshifting patterns of agriculture therefore can have net impact on the food security situation in the Punjab-Pakistan

Assessment and Validation of Land Surface Temperature (LST) Dynamics using Geo-spatial Techniques in Dera Ghazi Khan City, Pakistan

The integrated practice of remote-sensing and GIS techniques provides an active tool for assessment of spatial and temporal variability of land features. Based on literature, it can be suggested that various studies over the recent years have been carried out to explore the potential of geospatial techniques and were found highly efficient to understand the interdependency of landscape changes, land surface temperature changes (LST) and creation of Urban Heat Island (UHI) in major cities around globe. The current research was conducted in Dera Ghazi Khan, Punjab- Pakistan which is located at latitude 30.04587 N and longitude 70.64029 E. The Landsat 8 TIRS and OLI images were obtained free of cost from USGS e-data portal. These images have already been rectified to WGS-1984-UTM-Zone_43N. The meteorological data file (MTL) for Dera Ghazi Khan- contains the study was acquired from Pakistan Meteorological Department. As per results vegetation cover has been decreased up to 15 % from 2001 to 2021, which was directly affecting the land surface temperature. It has been observed that LST derived from the satellite was closely matched with ground climatic data; there was a mere temperature difference of 2°C to 3°C. It is concluded that LST was negatively correlated with vegetation cover of the area under study. It is suggested to implement road map as provided in Dera Ghazi Khan Master Plan-2021 in order to have a control on unplanned landscape changes, urban evolution and rapid population growth

Assessment and Validation of Land Surface Temperature (LST) Dynamics using Geo-spatial Techniques in Dera Ghazi Khan City, Pakistan

The integrated practice of remote-sensing and GIS techniques provides an active tool for assessment of spatial and temporal variability of land features. Based on literature, it can be suggested that various studies over the recent years have been carried out to explore the potential of geospatial techniques and were found highly efficient to understand the interdependency of landscape changes, land surface temperature changes (LST) and creation of Urban Heat Island (UHI) in major cities around globe. The current research was conducted in Dera Ghazi Khan, Punjab- Pakistan which is located at latitude 30.04587 N and longitude 70.64029 E. The Landsat 8 TIRS and OLI images were obtained free of cost from USGS e-data portal. These images have already been rectified to WGS-1984-UTM-Zone_43N. The meteorological data file (MTL) for Dera Ghazi Khan- contains the study was acquired from Pakistan Meteorological Department. As per results vegetation cover has been decreased up to 15 % from 2001 to 2021, which was directly affecting the land surface temperature. It has been observed that LST derived from the satellite was closely matched with ground climatic data; there was a mere temperature difference of 2°C to 3°C. It is concluded that LST was negatively correlated with vegetation cover of the area under study. It is suggested to implement road map as provided in Dera Ghazi Khan Master Plan-2021 in order to have a control on unplanned landscape changes, urban evolution and rapid population growth

River Profile Modeling Through Surface Deformation Using RS/GIS, A Case Study Swat River

The objective of this appraisal is to determine the feasibility of dam sites in Swat Valley and its peripheries (Northern Pakistan). We exploited SRTM DEM with a spatial resolution of 90m to extract various geomorphic indexes for the dam site feasibility. This research aims at pinpointing areas which can be opted for small dam constructions to overcome the electricity crisis in Pakistan to some extent to meet the national electricity needs. We exercised River profile analysis (RPA), D8 flow popular algorithm, Concavity, Steepness, and Hack-gradient methods to prepare interpolated maps for the Steepness index, Concavity index, Relative uplift rates, and other parameters like value zoom, vector zoom, surface zoom, density zoom, relief zoom and contour map. The drainage pattern of this area indicates that there are high relative uplift rates, erosion, steepness and concavity in NE, NW and SW. The DEM based RPA develops as much easier and faster approach to demarcate sites influenced by neotectonics. Full Tex

Flood Inundation Mapping using Multi-temporal Datasets

Floods are considered the most frequent natural catastrophic events, which effect the human lives and infrastructure. Flooding causes tremendous loss of life and property every year. We used satellite imagery to map flood inundation in Jehlum river for the both pre and post flood scenarios and classified it into major landuse including vegetation, water body, buildup land and the bare soil. The results show that about 40% area was agricultural land, 29% was bare soil, 16% was build up land and 12% area was noted as water body.The categorization of the post flood areas, showed that flood has destroyed the buildup and agriculture lands.The superimposition proposed that agricultural land was 43% before the flood which reduced up to 31%,the normal flow of water was 12% before flood which was increased up to 33%, build up area and bare soil was also decreased up to 10% and 25% respectively. Remote sensing and GIS proved efficient in convergence of optimistic results. Full Tex

Flood Inundation Mapping using Multi-temporal Datasets

Floods are considered the most frequent natural catastrophic events, which effect the human lives and infrastructure. Flooding causes tremendous loss of life and property every year. We used satellite imagery to map flood inundation in Jehlum river for the both pre and post flood scenarios and classified it into major landuse including vegetation, water body, buildup land and the bare soil. The results show that about 40% area was agricultural land, 29% was bare soil, 16% was build up land and 12% area was noted as water body.The categorization of the post flood areas, showed that flood has destroyed the buildup and agriculture lands.The superimposition proposed that agricultural land was 43% before the flood which reduced up to 31%,the normal flow of water was 12% before flood which was increased up to 33%, build up area and bare soil was also decreased up to 10% and 25% respectively. Remote sensing and GIS proved efficient in convergence of optimistic results. Full Tex