Road expansion
Increases in population size and GDP, particularly in developing nations, are the primary drivers of road expansion[1] but transportation planning decisions also play an important role.
Road expansion in Asian countries is a significant aspect of infrastructure development, driven by urbanization, economic growth, and connectivity needs.
Countries like China, India, and Indonesia have ambitious plan for expanding their road networks to accommodate increasing traffic and trade demands.
These projects often face challenges related to land acquisition, environmental impact, and funding, but they play a crucial role in fostering economic development and improving accessibility for remote regions.
Roads facilitate access to markets, health services and education but may adversely affect the natural environment, and impact communities and economies.
[7][6][8][9] Habitat fragmentation caused by road expansion can impact the movement and migration of species, as well as breeding and genetic structure.
[23][25][26][27] A strong positive correlation has been observed between road building and deforestation in regions such as the United States,[26] Europe,[28] and China.
In Central Africa, the strongest predictors of decline in elephant populations were proximity to expanding infrastructure and the absence of law enforcement.
[9][32][33] In equatorial West Africa, the collapse of gorilla and chimpanzee populations was primarily caused by hunting that was spurred by a rapid expansion of road networks, which facilitated poaching as well as habitat conversion.
[34][35] Where forest management is weak, road expansion proceeds unregulated and can be allowed to fragment crucial bioregions and protected areas.
Improved road infrastructure has reduced poverty by facilitating higher production and exports in Peru,[37] Bangladesh,[38] and parts of Sub-Saharan Africa.
Moreover, budgeting high construction costs, but building substandard roads which require higher levels of maintenance are both common practice and a major drain on public expenditure and private investment.
[56] Such activities escalate costs and reduce the usable lifetime of roads, and are particularly evident in many developing countries where corruption is more pervasive and implicitly tolerated.
In Indonesia, improved roads allowed job creation in manufacturing industries and an occupational shift amongst workers away from agriculture.
[64] Conversely, a greater supply of people seeking employment can drive down the wages in an area, producing a negative effect on livelihoods.
Large road projects generate an influx of temporary migrant workers, which increases the demand for services such as prostitution and black-market products.
[citation needed] The traditional culture and lifestyles of indigenous groups that have lived in remote areas for many generations are substantially altered by new roads.
[73][80] The influx of non-indigenous migrants through road building, and the associated intensification of contact, create inter-group conflicts, such as seen between indigenous Amazonian tribes and loggers or gold miners.
[84] In northern Sumatra, Indonesia, proposed road developments extending the Trans-Sumatran Highway if they were to occur will affect six of the eight local conservation priority areas of the Leuser Ecosystem,[85] comprising 89% of the remaining Sumatran orangutan's habitat.
[86] In fact, Forest conversion due to road development in this region has been projected as a major factor influencing the decline in orangutan populations.
Many roads in remote areas have uncertain socio-economic benefits and surprisingly high economic, social, and environmental risks, and a cost-benefit analysis of 33 planned 'development corridors' in sub-Saharan Africa concluded that less than one-fifth of the projects were clearly justified.
