The ecological and economic values of secondary forest on abandoned land in Samarinda, East Kalimantan Province, Indonesia

Abstract

There is a large area of abandoned land in East Kalimantan Province. These abandoned traditional gardens which have been neglected for a long time have important ecological and economic values. This study aimed to assess the ecological and economic values of secondary forest on abandoned land in Samarinda, East Kalimantan Province. The ecological aspects assessed were stand structure, floristic composition, and species diversity. Meanwhile, the economic aspects analyzed were log price, harvesting cost, profit margin, and stumpage value. The vegetation survey was carried out on all woody trees with a diameter at breast height (DBH) > 5 cm in 10 subplots, each measuring 20 m × 20 m. A total of 192 trees were recorded, belonging to 29 species, 19 genera and 17 families. The most dominant species were Macaranga triloba (Importance Value, IV of 46.16), Macaranga tanarius (IV of 22.97), and Nephelium lappaceum (IV of 20.94). The indexes of diversity, dominance, evenness, and richness in the studied plots were 1.33, 0.06, 0.40, and 5.33, respectively. The means of wood price, logging cost, profit margin, and stumpage value of the secondary forest were USD199.55 m-3, USD69.01 m-3, USD25.45 m-3, and USD51.56 ha-1, respectively. This study confirmed that the abandoned land had high ecological and economic values.