10.4.6 Human dimensions
Study of social vulnerability provides a complementary approach to the study of climate impacts based on model projections and biophysical simulations. Adger et al. (2001) illustrate the approach through theoretical discussion and case studies based in Vietnam. The following sections detail specific examples of the human dimension of general relevance within Asia.
10.4.6.1 Population growth
As of mid-2000, over 3.6 billion people, roughly three-fifths of the total population of the globe, resided in Asia. Seven of the world’s 10 most populous countries - China, India, Indonesia, Russia, Pakistan, Bangladesh and Japan - are located within Asia (ADB, 2002). The majority of the region’s population growth is forecast to come from South Asia, which expects to add 570 million people in India, 200 million in Pakistan and 130 million in Bangladesh over the next 50 years (UN-DESA-PD, 2002). Population growth, particularly in countries with already high population densities, is inextricably associated with the increasing pressure on the natural resources and the environment as the demands for goods and services expand. Some of the key impacts of increasing population include those linked with the intensification of use of natural forests including mangroves, agriculture, industrialisation and urbanisation. In Asia, the pressure on land in the 21st century will increase, due to the increasing food grain demand for the growing population, the booming economic development, as well as climate change. This will be exacerbated by the increasing scarcity of arable lands as a result of using vast agricultural lands to support industrialisation and urbanisation in pursuit of economic development (Zeqiang et al., 2001).
In the developing regions, the remaining natural flood plains are disappearing at an accelerating rate, primarily as a result of changes in land use and hydrological cycle, particularly changes in streamflows due to climatic and human-related factors. The future increase of human population will lead to further degradation of riparian areas, intensification of the land and water use, increase in the discharge of pollutants, and further proliferation of species invasions. The most threatened flood plains will be those in South and South-East Asia.
In some parts of South-East Asia, population growth, particularly in the uplands, continues to exert pressure on the remaining forests in the region. Encroachment into forest zones for cultivation, grazing, fuel wood and other purposes has been a major cause of changes in natural forests. In the Philippines, forest degradation has been attributed partly to upland farming (Pulhin et al., 2006).