SN

Factors

Lagos

Shanghai

1

Slum

Ø Globally, Lagos is one of the most populated cities, with over 14 million residents. World Bank reports showed that over 70% of Lagos residents live in unplanned settlements called slums without access to basic facilities such as clean water and hygiene [36] .

Ø Poor planning, high population growth, urbanization, and inequality are reasons behind this problem of unplanned settlements still available at a high percentage of 70.

Ø Based on a systematic survey conducted, it was confirmed that Shanghai is a developed city and has no slums. This process of examining whether Shanghai has slums or not was based on on-site visits, interviews with urban officials in the water and sanitation sector, meetings with some Chinese scholars, and seminar discussions with staff and students at Chinese universities [37] .

Ø Good land use planning.

2

Water quality

Ø Lagos mainly faces water quality-related problems due to improper disposal of raw dirt and residue carried through runoff, resulting in serious health concerns. Accessibility to clean water is significantly low. Many Lagos inhabitants mainly depend on boreholes, wells, streams, and rainwater. However, Lagos is a metropolitan bounded by much water with over 2000 mm of annual precipitation, but it is unsafe to drink. Consequently, this high demand for clean water results from urban expansion [38] .

Ø Water pollution, inadequate sanitation, and urban sprawl/expansion are the leading causes.

Ø Due to the rapid development of Shanghai in the past many decades, numerous water channels have become seriously contaminated. Moreover, just 3% of the water in the city was adequately clean to drink. In addition, researchers showed that rapid urban growth correlated with the rapid lowering of water quality in Shanghai [39] .

Ø Moreover, despite its significantly higher level than Lagos, Shanghai encounters water pollution issues due to urbanization.

3

Air pollution

Ø The different reports indicated that Nigeria is the 10th most contaminated country in Africa, with a 44.8% rate of air pollution due to urbanization. Moreover, air pollution in Lagos is mainly caused by the different aspects of urban expansion, like road transport, which is the most significant source of PM2.5 of air pollution at 30%, and mismanagement of waste [38] .

Ø Urbanization, poorly planned road transport, and waste mismanagement are drivers of the problem.

Ø Shanghai has experienced the problem of air pollution due to urban expansion. Car and industrial unit releases count for at least 50% of Shanghai’s contaminated air. 10.5% originates from destruction and rebuilding sites. In addition, pollution in Shanghai also comprises the wastewater settled and waste gas released in the atmosphere [39] .

Ø Urbanization and inadequate zoning practices play significant roles in issues similar to those experienced in Lagos. However, the problem is exacerbated by industries, excessive car usage, and air transport, which are more prominent factors than Lagos. Such factors are abundant in Shanghai, and lessons can be learned from Lagos’ approach to addressing these challenges.

4

Urban heat land

Ø More than 78% of Nigerians live in cities, which impacts climatic variations. Lagos Metropolis is situated in a region of significance for rapid urbanization, which has produced an extraordinary Urban Heat Island (UHI) effect [40] .

Ø Shanghai’s urban heat island (UHI) effect is primarily attributed to urbanization and the dense population like Lagos. Therefore, Lagos can benefit from Shanghai’s experience in implementing environmentally friendly policies by learning from them.

Ø As an important economic center in China, Shanghai has experienced much growth in the past few decades. Farmland and vegetation are replaced by an urban-resistant surface, leading to a severe Surface Urban Heat Island (SUHI) effect, especially in the urban center. Furthermore, due to proper urban planning and appropriate green policies since 2010, the SUHI trend has slowed [35] .

Ø Urban Heat Island has been effectively addressed through environmentally friendly policies since 2010, thanks to the implementation of appropriate urban planning measures.