Rapid albeit unplanned urbanisation in the provincial capital has not only been creating social problems, it is also adversely impacting the city’s ecosystem, Pakistan Today has learnt.

According to estimates, the population of Lahore has topped 10 million. From 1901 to 1921, the annual average growth rates remained slow, but the rate of population picked up after the Independence, shows data available with this scribe. It increased at a faster rate ie, 2.38 and 4.32 per cent during the periods 1951-1961 and 1961-1972, respectively. This has registered a corresponding increase in the population of 52.65 and 67.36 per cent.

According to geologist Dr Safdar Ali Shirazi, this increase can be attributed to a substantial migration from rural areas to urban centres. He said that the drop in an average annual growth rate to 3.71 per cent during 1972-1981 and a further decrease to 3.32 per cent for 1981 to 1998 were due to the intra-urban residential motilities from the inner city towards the suburbs.

“This large-scale increase in the population and resultant development in the residential or infrastructural sectors caused an increased pressure on urban vegetation and disturbed the ecosystem of the city,” Shirazi said. “Therefore, the urban vegetation has been significantly reduced and thus has a significant socio-environmental impact on the residents of the city,” he added.

Another expert, Dr Uzma Khan, was of the view that the rapid construction work had hampered the ecosystem badly. “The reduction in the greenery has caused a significant reduction in biodiversity,” she said, as she pointed out reduction in parakeets, mango, guava and jambolan trees which used to be in abundance in the past.

Uzma said that the ecological meltdown was a consequence of changes to the ecological communities in the fragmented habitats driven by the disruption of ecological interactions through the losses of species with the higher tropic roles. “If a city expands, then that land is no longer useful for agriculture, and hence production goes down and in the case of new constructions the soil is disturbed which removes the stored carbon,” she added.

She believed that the unpaved green belts fell under green areas across the cities which were of great worth since they helped in water drainage and in stability of the groundwater. In an urban life, ecosystem has a great importance because trees absorb the carbon dioxide and there are a lot of vehicular emissions like carbon monoxide and other toxic gases and if for some reason trees are cut, the natural cleansing process stops. Talking about the importance of trees, she said that the trees also provided food and abodes to birds. Uzma said that the importance of the green belts had been very evident. “The PHA had been informed of the ways to preserve the green belts and roadside trees in the case of necessary construction,” she added.

“Once almost all the roads in the city were covered with trees which used to be the habitat of different birds but all that has vanished. This was done just for the sake of roads and other construction works,” said Dr ZB Mirza, recalling the 1960s.

“In an ecological system, vegetation and birds are much important. In old Lahore there were wider and emptier streets,” he said, and added that there used to be more trees and less high-rise buildings,” jhe said. “Unplanned construction has been widely carried out in the city where trees were planted. Now, we see high-rise buildings, roads and housing societies, but almost no greenery,” Mirza added. Environmental lawyer Ahmad Rafay Alam was of the view that while unplanned and haphazard urban planning practices in Lahore created structural conditions for traffic congestion, inequality and loss of productivity, it also worked to reduce biodiversity in urban areas.

Rafay believed that the urban ecosystems provided important services that urban residents relied on for a daily living. He said that ecosystems could supply clean water, produce food, absorb air pollution, mitigate urban heat, provide opportunity for recreation. Unplanned and haphazard urban growth can result in development far from consolidated urban area, and such horizontal sprawling urban growth results in exponential increases in the capital investments required to bring services to such locations as well as the maintenance costs of the extensive network of roads, sewage mains and waste collection and elimination systems, among many other basic services,” Rafay said, while giving reasons of disruption of ecosystem of the city.

He added that authorities should be concerned regarding the ecosystem while making a master plan for the city.

Talking about the recent Master Plan for Lahore, Rafay said that the current plan was unsustainable and unreasonable as it would promote low-density sprawl at the cost of a prime agricultural land.

Dr Uzma suggested that instead of building pressure in the city like Lahore, the government provideed people of rural areas with all the basic facilities at their doorsteps so that they could avoid coming to Lahore for better prospects.