Assessing hydrological situation of Kapuas Hulu basin, Kapuas Hulu regency, West Kalimantan uri icon

abstract

  • This report presents results of a â??rapid appraisal â?? of the hydrological situation in Kapuas Hulu Basin, Kapuas Hulu Regency in West Kalimant an (Indonesia). The main objective of this study was to assess the hydrological situation of Kapuas Hulu Basin and to provide information on what and where the payment for watershed servi ces could be focused. In the upstream of Kapuas Hulu Basin lies Batang Kerihun National Park, one of the last frontiers of natural habitat in Kalimantan. The National Park is a hot-spot biodiversity area containing thousands of different plant and animal species, many of them endemic to Kalimantan. Kapuas Hulu has a very wet climate, with an av erage annual rainfall of 4100 m/year. Rainfall is evenly distributed throughout the year with the wettest month in November or December. The dominant land cover class in Kapuas Hulu Basin is forest (90%). Lands that are managed by farmers (in form of agriculture and tree-based systems) only formed around 3% of the total area. There are three main catchments in Kapuas Hulu Basin: Sibau, Mendalam and Kapuas (Koheng). The intensity of land management vari es between catchments, with Sibau the most intensive (vegetable plots, tree-systems a nd tembawang) and Kapuas the least intensive (gathering forest products and tembawang). Currently, forest areas in Kapuas Hulu are under th reat of being lost and fragmented due to fire, logging and mining activities. The local stakeholder (local community and policy makers) are concerned about the impact of loss of for est cover on watershed hydrological functions, particularly on water level and water quality (e rosion, sedimentation and pollution). Boats are the main transportation for people in the area, thus stable and sufficient river depth is desirable. Water quality issues in the area are related to wate r turbidity due to erosion and sedimentation, as well as pollution. The hotspots areas of Kapuas Hulu Basins are in Sibau Hulu village of Sibau catchment and Datah Dian village of Mendalam Catchment. These villages are the most upstream villages in the basin and the location where most land use change by local communities are occurring. The average annual precipitation in the Kapuas Basin is approximately 4100 mm/year. The landscape water balance in Kapuas indicated that around 60% flows into the river, while 40% is used by the vegetation in interception and transpiration. According to the model, only 0.5 % of rainfall come as surface run-off, 16% as soil quick flow (interflow; reaching the river within 2 days after the rain) and 39% as base flow

publication date

  • 2008