In Pacific Small Island Developing States (PSIDS), the degradation of mangroves advances at a fast pace, especially in urban places. Rural to urban migration let urban settlements grow tremendously in the past 60 years. People built many informal settlements straight into mangrove forests. Health implications are severe, but settlements in mangrove forests provide protection against eviction. The case study provides insight into people's lives, perception and actions in a degraded mangrove forest in the eastern part of Suva, the capital of Fiji. The major question is why people are exposing themselves to serious environmental health hazards. Based on recent changes, the chapter also looks at development efforts that threaten residents of informal settlement to get evicted from the locations they right now reside. Investigations concentrate on people's actions in space, particularly, the role degraded urban mangroves play in their decision to reside in a particular place. A major explanation is that people want to reduce risk and enhance security: security from eviction.
TopUrbanization And The Destruction Of Mangrove Forests
Mangrove forests play a crucial role in coastal ecosystems and coastal protection. They provide multiple benefits to people such as filtering and moistening the air, regulating micro-climate, acting as buffer zones against flooding, allowing rivers to spread, protecting against sea surges and tsunamis, providing food, fire and construction timber, and traditional medicines to poorer sections of societies (Wang, Jia, Yin, & Tian, 2019). These functions and services also apply to urban mangrove forests. Still, for many decades, urban planners and politicians have ignored the importance of mangrove forests. Mangrove destruction often happened unnoticed and unopposed. In the question of analyzing the opportunity cost, these resources were paid less importance than economically valuable agriculture, aquaculture, industrial and urban development. Thus mangroves were destroyed and degraded for other economic conversions.
By the beginning of the 21st century, an estimated one third of global mangrove forests had been lost within the past 50 years (Alogni, 2002; Wang et al., 2019). In 2007, scientists feared that within 100 years mangrove deforestation and destruction would be so extensive that most of their functions disappeared (Friess et al., 2019). Scientists estimate that annually 1-2% of global mangroves did disappear and the deforestation rate is higher than for tropical rainforests (Rodríguez, 2018). Confirmed and up-to-date figures on the global extension of mangrove forests are difficult to get. For the beginning of the third millennium Spalding, Kainuma, & Collins (2010) put the global size of mangrove forests at “just over 150,000 km2”. Fries et al. (2019) gave a figure of 137,600 km2 for the year 2010. The latest figures are available for 2015 from the FAO database on Global Forest Resources Assessments (2015). According to this assessment, there were 117,000 km2 of mangrove forests worldwide.
In Asia and the Pacific, mangrove forests have been particularly exposed to human activities. The region, which has almost half of global mangrove forests, loses them much faster than any other place in the world (DasGupta & Shaw, 2017). In some countries, the decline in mangrove forest cover has been spectacular. Within eight years (1992-2000), the mangrove cover along the Pakistan coastline has decreased from 122,000 ha to 73,000 ha (Rahman & Shaw, 2017). In Myanmar mangrove cover shrank by 52% between 1996 and 2007 (De Alban, Jamaludin, de Wen, Than, & Webb, 2020). It was possible to mitigate severe dangers of degradation in the Sundarbans of West Bengal in India, and Bangladesh through community-based Joint Forest Management Programs. Sundarbans of West Bengal and Bangladesh comprise the world’s largest contiguous mangrove forests. High population densities and people’s poverty continue to be a major threat to these forests (DasGupta & Shaw, 2017). Also, in Africa and Latin America, vast areas of mangrove forests disappeared in the past few decades. This process continues unabated.
Among the many causes of mangrove degradation, urban development does not figure on top of lists (see below). Still, it has contributed much to the disappearance of mangrove forests in locations where a high density of people live. But, the forests compromise the protection of settlements against hazards that come from the sea, such as tsunamis (Kathiresan & Rajendran, 2005) and tropical cyclones (Das & Vincent, 2009).
In many urban areas, mangrove forests today exist only as tiny, highly fragmented patches. Remaining mangroves are often heavily polluted from liquid effluents of industrial complexes and untreated sewerage. Solid waste, in particular ever-increasing plastic waste, let mangrove forests appear like rubbish dumps rather than recreational places they actually could be.
Bunt (1992) highlighted that in the early 1990s irreversible damage was caused by reclamation of urban mangrove forests throughout the tropic. It comes therefore as a surprise that relevant literature rarely covers urban mangroves. 30 and more years ago publications about mangrove forests missed the word ‘urban’ entirely (e.g. Jaccarini & Martens, 1990; Wong & Tam, 1995). Even an edited book in 2009 dedicated to the ecology, planning, and management of urban forests from international perspectives (Carreiro, Song, & Wu, 2007) does not contain the word ‘mangrove’.