Abstract
Despite recognizing the role of wetlands in providing ecosystem services
to human wellbeing, around 70% of the wetland ecosystems are destroyed
globally since the 1990s. In particular, wetland ecosystems are
destroyed in response to faster economic, urban, and population growth
in the world megacities and developing countries. In contrast, wetlands
ecosystems have received less attention in research and policy.
Therefore, we made a first attempt to unravel the Spatio-temporal
dynamics of wetlands in the Dhaka city of Bangladesh, which is one of
the fastest-growing megacities in the world. The results show that a
total of ~ 1,600 ha (~ 50% of the total
wetlands) wetlands have been lost in Dhaka from 1990 to 2015. In
contrast, the land-use types that increased the most were built-up,
which increased by ~9,250 ha (378%) since 1990. These
changes are mainly due to rapid urbanization and industrialization. It
has been observed that Land Surface Temperature (LST) has increased 15
oC within 30 years in those lands which converted from wetlands to
landfill. In addition to the increase in LST, drainage congestion,
depletion of groundwater are increasing in response to wetlands
degradation. The restoration of wetlands into the initial state of the
1990s would be highly challenging. However, efforts should be made to
restore wetlands which offers potential as a nature-based solution to
cope with climate change. These findings can be used as a reference in
the formulation and implementation of sustainable wetlands management
policies.