Adjustment of forested hillslope conservation technologies developed in Japan to meet local contexts and needs
In Vietnam, overuse of forest resources driven by growing market economy has caused degradation of mountainous areas, including landslides. We will develop methods for reducing the risk of sediment disasters in Vietnam by adapting Japanese forested hillslope conservation technologies that effectively utilize functions of forest ecosystems. Biophysical conditions and socioeconomic situations are taken into account. Field surveys will be carried out in degraded forest areas in the northwestern Vietnam to understand the spatial distribution, geomorphic characteristics, and vegetation effects of landslides. We will also explore data sets of topography, geology, rainfall, land-use etc. available in the country, and employ the data sets in GIS analysis. Since the forest degradation is often caused by improper construction of logging road networks, we will also make detailed survey into logging road networks in the target forest areas. In addition, we will investigate land-use and its history in the target areas, including changes in forest area, conversion to agricultural lands, and changes in residential areas. These information on landslides, forest roads and land use will be combined to develop landslide risk maps and forest management maps. Based on the risk map and land use information, we will propose zoning of the target forest area for future land-use planning effective in both disaster reduction/mitigation and forestry profitability.