Agricultural Land in the GMS (thousand hectare) in ... - GMS-EOC

whom 46 million live in Yunnan Province, PRC.Two agricultural systems exist: intensive farmingof highly productive, densely populated uplandriver valleys; and swidden agriculture andlivestock grazing of sparsely populated forestedterrains. This distinction is likely to remain, aslarge tracts of the forested uplands are steep,with poor, infertile soils. The boundaries betweenthe two will shift as degraded soils return toforests and new lands come into production.Intensive farming takes place on upland plainsand in river valleys, which are often terraced forgrowing rice. The subtropical climate gives way totemperate conditions at altitude, enabling a widerange of plants to grow. Major food crops includerice, maize, vegetables, wheat, and cassava.Important cash crops are vegetables, flowers,tobacco, coffee, sugarcane, tea, rubber, pepper, treefruits, cocoa, and mulberry. Farmers supplementirrigated wet-season rice with dry-season cropsof faba bean, wheat, oil seed rape, or sugarcane.They also raise livestock semi-intensively. Partialirrigation supports some cash crops, includingtobacco, vegetables, and coffee. Using groundwaterto irrigate coffee plantations in Viet Nam’sCentral Highlands has depleted water supplies.Traditionally, upland farmers derived theirlivelihoods from shifting or swidden cultivation(see next section), livestock farming, andby growing a limited number of cash crops.Upland fishing is insignificant economicallybut provides valuable protein to communities.Concerns about sustainability, the desire tolocate populations in areas where servicesexist, and various political and securityissues have led all governments to introduceprograms to resettle ethnic minorities anderadicate shifting cultivation. These policieshave prompted the expansion of permanentupland agriculture, often in unsuitable areas.Commercial plantations of rubber, timber, andoil crops are also increasing, particularly insouthern Yunnan, the northern Lao PDR, andparts of Myanmar. Wild-sourced timber remainsan important economic sector in the uplandsof Myanmar. A relatively high proportion offorest cover remains in the uplands, but it isshrinking. Rates of loss are high in Myanmarand the Lao PDR but have stabilized in YunnanProvince and Viet Nam, where replanting andrestoration programs have increased tree cover.Intensive upland farming causes catchmentwidesoil erosion. This decreases soil fertilityand overloads waterways with sediment. InleLake in Myanmar has shrunk in length from56 to 15 kilometers during half a century.Plantations also cause high soil erosionrates unless the understory is maintained.Above left: Weeding rice in the MekongDelta, Viet Nam. Above right: Satelliteimage showing a typical section ofthe Mekong Delta, almost completelyconverted to rice fields. Increasingchallenges are reduced freshwater flowsduring the dry season and seawaterintrusion due to rising sea levels.Agriculture, Fisheries, and Food Security 161