|| AttApeu, Lao PDR
Attapeu Province is the most south-easterly province in Lao PDR forming part of that country’s south-eastern borders with Vietnam and Cambodia and extending west to the Xe Kampar and Bolaven Plateaux. The east is mountainous with areas up to 2,000 metres above sea level, while the lowlands of the south west are about only 100 metres above sea level.
Attapeu Province has a total area of 10,320 km2. Of this, 7,350 km2 (71%) is forest and only 155 km2 (1.5%) is under cultivation. The total population is 92,947 divided amongst four districts namely Samaki Sai, Sai Setha, Snamsai, and Phouvong. The largest rivers in the province are the Xe Kong and Xe Kaman while smaller rivers include the Xe Pian, Xe Kampur, and Xe Xou. There are two National Biodiversity Conservation Areas in the province, Dong Ampham in the east and part of Xe Pian in the southwest. A proposed National Biodiversity Conservation Area, Dong Kathong, is in the northeast.
Biogeographically the province can be characterised as follows:
|•||Lowland plains include the Xe Kaman lowlands, Xe Xou lowlands, Attapeu lowlands, and the Xe Pian and Xe Kong plains. Lowland semi-evergreen forest, bamboo stands, secondary forests and open dry dipterocarp woodlands are common. In some areas there is rice cultivation and buffalo graze the forest understorey. Rapids are common in smaller rivers in the dry season. The most extensive wetlands are formed on the floodplains of the Xe Kong and Xe Plain in the south-western corner of the province. On this floodplain over 30 ‘nongs”, small ponds and marshes, occur in the dry dipterocarp forest and, together with rivers, form an extensive and relatively pristine lowland wetland complex. Seasonally inundated, this area is one of the more sparsely populated areas in the province. Many of these wetlands occur on old lava flows.|
|•||Mountainous areas occur in the eastern and northern parts of Attapeu province. They are characterised by large areas of undisturbed evergreen dry forest, semi-evergreen forest, sub-montane mixed coniferous and broadleaf forest, pine forests, montane evergreen forests, and wet evergreen forest. Some areas have secondary regrowth. There are a number of lakes and reservoirs in the upper catchments as well as the largest lake in the Annamite chain - Nong Patomkeen. |
|•||Foothills contain assemblages of open dry deciduous forest with bamboo and grass understorey, mixed deciduous and evergreen forest, and degraded dry evergreen forest. |
The wetlands found in Attapeu Province include:
|•||Ponds and marshes, called nongs in the Lao language, are small wetlands up to 300 hectares in area found within the mixed deciduous and dipterocarp forests. Some of these ponds are seasonally inundated, while other contain water throughout the year. They are often dominated by emergent vegetation including sedges, reeds and grasses, and sometimes support floating vegetation such as lotus Nelumbo nucifera and the alien water hyacinth Eichornia crassipes. |
|•||Lowland river channels are formed by the Xe Kong and Xe Kaman, which in the dry season are relatively wide and slow-flowing. In the wet season when water levels rise the Irrawaddy Dolphin, once common in these rivers, are still seen occasionally. These channels are important for the migration of fish from the plains to the higher tributaries. |
|•||Upland tributaries are characterised by the steep gradients and rocky substrates. Smaller streams flow through closed canopy forest, which opens as the streams widen. In the mountainous areas there are many streams and small rivers, which potentially support undescribed species of fish.|
|•||Rapids are common on all rivers in the province in the dry season. Particularly prominent in areas with a steep gradient, these areas probably support undescribed species of fish.||