32 research outputs found
Geo-spatial analysis of rainfall variability in Khyber Pakhtunkhwa Province, Pakistan
This paper explores geo-spatial analysis of rainfall variability in Khyber Pakhtunkhwa province, Pakistan. The concern region lies in the north-west of Pakistan and frequently faced the challenges of floods each year. This is an attempt to find out the rainfall trend and fluctuation which is one of the prime indicator of climate change. For this study, the daily rainfall data comprises of almost five decades (1975-2015). For achieving the study objectives, daily, monthly and mean annual rainfall data were analyzed using Mann-Kendall and Standard Deviation combined. Additionally, to further process the rainfall data spatio-statistically, GIS technology has been applied. The analysis specifies that a positive rainfall detected in the meteorological stations of Peshawar, Dir, Chitral, Drosh, Kakul and Saidu, whereas the moderate rainfall trend is detected in Cherat, Bannu, and Balakot. The remaining stations expressed no obvious trend, due to low time period of data
Spatio-Temporal Analysis of Areas Vulnerable to Urban Flooding: A Case Study of Lahore, Pakistan
Identification of existing hotspots is one of the principal steps for evolving strategy to mitigate urbanflooding, an emerging problem in mega cities of developing countries. Therefore, this paper aims to provide aframework of assessing the spatio-temporal hotspots of urban flooding incidents in Lahore district, Punjab, Pakistan.For this purpose, a database was created by gathering information of sore points by a governmental body, Water andSanitation Agency (WASA) to execute spatio-temporal analysis of urban flooding through hotspot analysis in spatialanalyst tool box in Arc GIS. Results show that urban flooding occurs in each town of Lahore excluding Wahga town.Among all affected towns of Lahore, Data Gunj Bakhsh town is noted as a highly affected area accounting 27 percentof urban flooding incidents during monsoon period from 2012-2017. Temporal study also shows an overall increasingtrend for incidents of urban flooding during 2012-2017. Moreover, detailed study shows that month of August isnoteworthy for urban flooding which is consistently increasing
The Preliminary Study of Anthropogenic and Natural Drivers of Desertification in Drylands of South Punjab, Pakistan
This study aims to investigate the perceptions of farmers residing in the drylands of south Punjab regarding the drivers of desertification mainly associated with meteorological and anthropogenic factors. Dataset of 399 respondents was collected using disproportionate stratified sampling technique from Bahawalpur, Rahim Yar Khan and Rajanpur districts. Pearson correlation and cross tabulation were performed to explore relation between variables. Simple Linear Regression (SLR) helped in investigating the association between natural and anthropogenic causes of desertification. The findings of this study indicate the significant variability in natural causes of desertification such as increasing temperature extremes, soil salinization and variation in rainfall patterns, while extensive land degradation, caused by anthropogenic factor, as leading to desertification in the study area. For Rajanpur, mean rainfall variation, supports the perception regarding major natural driver of desertification. Small-scale farmers were found to be most vulnerable to climatic extremes. SLR concluded that anthropogenic factors trigger or intensify the natural drivers of desertification in the study area. Useful insights are provided regarding the perceptions of the local farming community regarding causes of desertification as appropriate perception of a risk leads to fruitful adaptation measure
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
Evaluation of Residents Perception about Socioeconomic and Environmental Impacts of Urban Green Spaces of Lahore, Pakistan
In a country like Pakistan, the presence of urban greening and parks are very essential for the well-being ofits citizens. The resident’s awareness about urban green spaces (UGSs) is essential as it would not only help towards ahealthier environment, but prepare residents to manage these spaces efficiently through local resources. This formulatesthe rationale behind current research work. This research is aimed at studying about the resident’s perception for UGS’sattributes like environmental, negative and positive. Another major focus of this research is to analyze thesocioeconomic differentials and its consequent impacts on resident’s perception about urban green spaces, which hasbeen probed with the help of MANOVA (Multivariate Analysis of Variance). In this regard the primary data of 223visitors were collected by random sampling method from eight major parks of Lahore, Pakistan. The findings of thissurvey of resident’s perception have shown that mostly male, single, low and middle class, and educated people visitthe urban green spaces and they are highly indebted by their environmental and health benefits. For the selectedcharacteristics of urban green areas, the resident’s perception has revealed that there exists an insignificant relationshipwith age and marital status of the respondents while the most significant relation was shown by the residents whovisited the UGSs regularly as ‘ρ’ value is less than the set significance level of 0.05. This study has highlighted a direneed of such UGSs in the city of Lahore which is known to be the “City of Gardens”. This could raise the spirits ofadministrators, city managers and planners to take immediate action in this regard
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
Examination of Temperature Variability over Lahore (Pakistan) and Dhaka (Bangladesh): A Comparative Study
Lahore and Dhaka are rapid expanding and over populated cities of South Asia located in Pakistan andBangladesh respectively. The present study focuses on the evaluation of temperature variability in comparison of bothcities. This study primarily aims at the assessment and examination of temperature variations in both mega cities ofSouth Asia which are seasonal as well as the annual. The time series data were analysed by using statistical techniquesAutoregressive Moving Average Model (ARMA) and Autoregressive Integrated Average Model (ARIMA). The resultsreveal that the minimum temperature is increasing much faster than that of the maximum temperature of both cities.However, the temperature rise(in maximum and minimum) has been observed highest during the spring seasons in bothcities
Urban Floods and Suitability Analysis of Rainwater Harvesting Potential Areas in Lahore City, Pakistan
There is a growing threat of urban flooding, particularly in Pakistan that needs attention and requires effective management strategies. The chief trigger for urban flooding is the rapid and unplanned urbanization in areas where impermeable surface inhibits rainwater diffusion and changes the natural water flow. In many developed countries, a technique of rainwater harvesting is implemented as a sustainable strategy to manage urban stormwater. Most studies and projects chiefly focused on the potential use of the Rainwater harvesting technique for water conservation in arid and semi-arid climates. In the present work, GIS and remote sensing methodologies are utilized for the suitability of rainwater harvesting structures. This study was conducted in Lahore, the second most populated city of Pakistan and the capital of Punjab. Generally, the water harvesting technique depends on topographical areas with water accumulation, where there is an availability of open spaces in the form of green areas and barren lands, rainfall, drainage network density, and rainfall distribution, particularly in the urban environment. The SRTM DEM data were used for finding high water accumulated areas, and the Landsat OLI image is used to retrieve land use information i.e. vacant land and open green spaces, existing drainage network density, and rainfall distribution. All these layers were integrated through AHP to detect the potentially suitable sites for the construction of rainwater harvesting structures. Results concluded 94 suitable sites with categorization from highly to critically suitable for the construction of rainwater harvesting structures in which 6 were highly suitable areas in Data Gunj Bakhsh Town and Ravi Town. Besides, residential areas are having a maximum site suitability percentage, followed by roads, agricultural and open spaces in the area under consideration. Considering the suitable sites, further rainwater harvesting methods can be identified in the study area to alleviate urban flooding and improve the urban environment