Houay Pano catchment
The 60 ha Houay Pano catchment is located in northern Lao PDR, in the mountainous region of Luang Prabang, which mostly consists of hills with very steep slopes (8% of the land with slope gradient exceeding 55%). The flat and gently slope (0 to 2%) represents less than 1% of the area and is located in the valleys. Elevation ranges from 290 to 2257 m above sea level.
Houay Pano stands near the village named ‘Lak Sip’, about 10 km south-east of Luang Prabang city, along the National Road 13 and 400 km North from Vientiane.
The coordinates of the Houay Pano catchment are between 102°09’50’’E and 102°10’20’’E, 19°51’00’’E and 19°51’45’’N.
The climate is tropical sub-humid. It usually can be divided into 3 seasons: a dry and cold season lasting from October to February, a dry and hot season lasting from March to April and a wet and hot season from April to October. The mean annual rainfall at Luang Prabang is 1268 mm with a coefficient of variation of 28% (1960±2006). In average, about 91% of rainfall occurs between April and October.
The stream flow is permanent. Currently, 3 sub-catchments are monitored (S4, S7 and S8).
The most common rock types are gabbro, diorite, and basic rocks, such as schist, gneiss, and sandstone (Department of Geology and Mines, 1990-1991).
A detailed soil survey conducted by the Soil Survey and Land Classification Center (SSLCC) in 1996 showed that the most widespread soil groups are Acrisols, namely Alisol (FAO UNESCO system) or Ultisols (US taxonomy). They are mainly found on the slopes ranking from 8% to 50%, i.e. on most of the surveyed area.
Vegetation and land use
The land use gradually shifted from annual crop to teak plantations.