The second most common type is shifting cultivation, spanning the highlands from South Asia and South-East Asia. Shifting cultivation is based on adequate precipitation that supports luxuriant vegetation growth. The third type, rudimentary, sedentary farming, is widespread in areas where rainfall is low. The fourth type, intensive subsistence tillage, is mainly rainfed in humid regions and based on irrigation in the drier west. Plantation agriculture is confined to the highlands of South, South-East, and East Asia where tea, coffee, and other cash crops are grown.
Forests constitute an important resource in the Asian mountains.
If inaccessibility preserved them in the past, this same factor acts as a constraint to their commercial exploitation. Asian mountains are also rich in minerals, but these occur mainly outside the Alpine fold system on older rock formations. Central Asia and eastern Australia are particularly well endowed in iron, copper, tin, lead, zinc, gold, and silver. Iron is mined in peninsular India, in Korea, and in west Australia. Tin is mined mainly in South-East Asia and copper in Japan, the Philippines, and eastern Australia.