摘要
Land-Use/Cover Changes(LU/CC)are occurring rapidly in South/Southeast Asian(S/SEA)countries,generally associated with population growth,economic development and competing demands for land.In the region,the most common LU/CC changes include urban expansion,agricultural land loss,land abandonment,deforestation,logging,reforestation,agricultural expansion,etc.Specific to South Asia,forest cover has been increasing in countries like India,Nepal,and Bhutan due to sustainable afforestation measures;whereas,large-scale deforestation in Southeast Asian countries is continuing,for example,due to oil palm plantation expansion driven by the international market demand in Malaysia and Indonesia.Small-scale deforestation in most of the Southeast Asian countries is due to slash-and-burn agriculture by indigenous people,driven by poverty and population growth.Logging activities are common in Myanmar and Cambodia.In terms of urbanization,South and Southeast Asian countries contain 23 megacities,each with more than 10 million people.Megacities in these countries started as urban clusters which grow rapidly,merging into conurbations.Rapid urbanization is driving agricultural land loss,and agricultural intensification has been increasing due to less availability of land for growing food crops as,for example,in India,Vietnam,and Thailand.The drivers of LU/CC vary widely in the region and include such factors as land tenure,local economic development,government policies,inappropriate land management,land speculation,improved road networks,etc.Also,variability in the weather,climate,and socioeconomic factors drive LU/CC resulting in disruptions of biogeochemical cycles,radiation and surface energy balance.
