Multi-purpose riparian forest design for conservation and reduction of non-point source pollution in the Lake Toba catchment

Abstract

Abstract The riparian forest as a filtering zone is the strategy to reduce non-point source pollution and increase forest cover around the catchment area. The aim was to establish a riparian forest design that is effective for the conservation and reduction of non-point source pollution which also giving beneficial socio-economic for the people. The method used were a literature study as basic reference and vegetation field surveys. The vegetation survey was carried out using nested plots at the river riparian area in the Lake Toba catchment. The vegetation seedling and saplings stand level samples were collected, and that biomass were analysed to determine N and P content. Each potential absorbing of N and P species was grouped based on its habitat. A total of 24 plant species were selected to develop a multi-purpose riparian forest design in the Lake Toba catchment. The design of the multi-purpose riparian model recommended the plantation for dry areas, semi dry areas, and wet areas. Plantation in the dry area consisted of multi-purpose tree species, in temporary dry areas can be planted ornamental perennial herbs, and wet areas comprised of species absorbing water pollutants.