Lagos metropolis, the current economic capital of Nigeria is a low-lying coastal city endowed with a number of lagoons and wetland ecological assets. Lagos/Lekki Lagoons being the largest with a combined size of 646km2 are fringed on many sides by wetlands. Many of these wetlands have undergone severe spatial changes from rapid urbanization in the past three decades. The precise nature of these changes is largely unknown and unreported. As the area is experiencing intense development pressure, this study therefore examined the spatial changes in the wetlands fringing these lagoons using the integrated approach of remote sensing data and GIS with topographic maps providing baseline data. The objective is to quantify and establish the precise location and magnitude of these changes over the years from 1984 to 2006. Two types of wetlands are prevalent in the Lagos area namely: the swamps and mangroves. ENVI software was used along with parallelepiped supervised classification in processing the Landsat images. Results show that the mangrove wetlands decreased from 88.51km2 to 19.95km2 at -3.12km2 annually while swamps decreased from 344.75km2 to 165.37km2  at - 8.15km2 annually both between 1984 and 2006. Results further show that mangroves which were widespread in seven council areas around these lagoons in 1984, have dwindled to only four councils in 2006. These decreases are attributable to urban development pressures. Some of the implications of these losses and conservation issues are briefly highlighted.

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Temperature is an important component of the climate. The temperature of a developing city or state is constantly changing. The trend in temperature change in Nigeria is not consistent. Changes in temperature appear to be closely related to concentrations of atmospheric carbon dioxide. The degree of concentration depends on human interventions and the amount of sunlight reaching the earth's surface. Lagos State particularly in recent time has experienced decrease in vegetation and water pervious surfaces, which reduces surface temperature through evapotranspiration. This is as a result of rapid urbanization arising from inundating rural-urban migration. One of the implications is that anthropogenic heat is released to the environment due to energy consumption and increased impervious surface coverage thereby increasing the surface and atmospheric temperatures. LandSat Satellite imageries have been used to estimate Land Surface Temperature (LST) and urban thermal conditions. The mean LST result shows that, there is a significant increase in the temperature values from 1984 to 2002 (28.40 0 C-28.86 0 C). However, in 2006 the temperature decreases significantly to 28.37 0 C below 2002 temperatures in all LGAs. This variation could be attributed to the economic crisis/power outage in Nigeria which left manufacturing companies out of production/manufacturing between 2002 and 2006. Findings from this study reveals that there is a relationship between the surface temperature and the various Land Cover types. It shows a broad classification of the Land Cover types into Water bodies, Vegetation and Built-up areas respectively. With the spatial resolution and temporal coverage of two Landsat data of the environment, the derivation of the temperature information was achieved.

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Land Surface Temperature (LST) is one of the key environmental parameters affected by land cover change. Lagos State has been experiencing an increase in surface temperature due to growing areas of impervious surfaces caused by anthropogenic urban sprawl. While the change in LST has been established, its continuous monitoring and relationship with continuing Land Cover (LC) changes have become imperative for appropriate management and policy actions. This study investigated the effect of land cover change on LST in the rapidly urbanising Lagos metropolis. Using spatio-temporal Landsat imageries with their thermal bands and ancillary data, land cover and LST changes were assessed from 1984 - 2015. The spatial patterns of LST and LC were derived to examine the response of LST to urban growth. Findings confirmed urban sprawl in previously rural areas northward of the metropolis in LGAs such as Ikorodu, Kosofe and those fringing the state’s border with Ogun State. This also confirmed new growth areas as occurring west of the metropolis in Amuwo-Odofin LGA. The results further showed that the rapid urbanisation in Lagos metropolis has altered the surface thermal environment as indicated by increased LST. Built-up area and bare land accounted for the highest increase in LST (as high as 1.5℃ in some areas) while wetlands and other vegetated areas played a vital role in moderating the surface temperature in areas they still occupy. This provides reasonable evidence for the appropriate authorities to institute requisite policies and actions towards moderating urban sprawl while ramping up the development of urban green infrastructure to counter global warming.