Effects Of Rapid Urbanization On Vegetation Cover In Major Cities Of Pakistan Using MODIS Data During 2001-2019

Vegetation is one of the most essential part of the terrestrial ecosystem.It is vital component for life on the earth as it provides a number of benefits to human beings as well as the environment by absorbing the harmful gasses present in the atmosphere.According to a number of studies and census the amount of population around the world increasing rapidly.This increase in the population is creating a huge impact on the vegetation cover around the world.Pakistan is among the countries where vegetation cover is affected highly because of the increasing population specially in urban areas.The primary object of this study is to analyze the impact of rapid urbanization on the vegetation cover for major cities of Pakistan.Vegetation cover was extracted from the MODIS vegetation indices monthly product(MOD13A3)data.MODIS-derived land cover type product(MCD12Q1)data was used to calculate the urban areas changed from year 2001 to 2019.Rural areas were calculated from the MODIS-derived urban and built-up lands by generating a buffer of 25 km around the urban areas.Change in the EVI(?EVI)was calculated from the difference between urban EVI and rural EVI.Nighttime lights time series data is widely used to extract the urbanized area,so it was also used in the present research to validate the results obtained from the MODIS data.It was observed that the urban and built-up lands increased significantly from year2001 to 2019 for Pakistan as a whole.Change in the amount of urban and built-up lands for Pakistan was recorded as about 50 km~2 per annum.Around 965 km~2 increase was observed between 2001 to 2019 by using MODIS derived land cover product data.The change in the amount of urban and built-up lands during the past decade(2001-2010)increased with a lower rate as compared to the recent years(2011-2019).The annual increasing rate of urban and built up lands for Pakistan was recorded about 27.04 km~2during the last decade which increased up to 89.12 km~2 during the recent years.All cities of Pakistan in the present research exhibited a significant increasing change in the amount of urban and built-up lands.An increasing urban area of about 32 km~2 was recorded for Lahore which makes it the city with highest change in the urban and built-up lands.While Hyderabad was the city with lowest change in the amount of urban and built-up lands from year 2001 to 2019.The overall average EVI for Pakistan was calculated for the year 2001 to 2019.The EVI change from year 2001 to 2019 was observed in increasing trend.The amount of EVI changed from 2001 to 2019 was observed with an increase of about 0.06 in the amount of EVI while the rate in increasing EVI was around 0.0027 per annum which in not that significant.The highest increase in amount of EVI was observed 0.0949 for Islamabad city and lowest EVI was observed 0.0287 for Multan city of Pakistan from year 2001 to 2019.?EVI was recoded in continuous decreasing trend from year 2001to 2019 for all the city of Pakistan under the present study.Highly significant decreasing trend(p<0.01)was observed for most of the cities of Pakistan in the present study.Pearson's correlation method was used to observe the relationship of increasing urban and built-up lands and decreasing?EVI.A strong negative correlation(p<0.01)between urban and built-up lands and?EVI was observed.Thus,the increasing amount of urban and built-up lands inserted a negative impression on the vegetation cover.DMSP/OLS nighttime lights time series data was used to validate the results obtained from MODIS data.A strong negative correlation(p<0.01)was observed between the urban area extracted from nighttime lights time series data and?EVI.