なぜマングローブ林は再生したのか?: ベトナム、カマウ省ゴックヒエン県の湿地利用制度とインセンティブ

Abstract

From the mid-1980s to the mid-1990s, the mangrove in Ngoc Hien district, Ca Mau province, suffered serious environmental degradation from human activities such as the conversionfrom mangrove wetland to arable land or to shrimp farming ponds. However, in the years1994 to 2000, while the population of the area and gross output of shrimp grew, the forestarea also rapidly increased. This paper examines why these phenomena occurred byfocusing on the role of formal institutions for natural resource utilization.The provincial authorities had made several regulations to promote forest since the1970s, but these had only stimulated local organizations and residents to exploit forests fortheir own benefit. The formal institutions did not result in collective action based onincentives for forest conservation, particularly after a land allocation policy was applied inthe district. The enforcement of land allocation to households imposed costs on localorganizations, such as land use investigation and the selection of households for landtenure. Moreover, households then had to invest in preparation for shrimp farming andtree planting on their land.Under the national forest conservation program 327-CT, implemented in Ca Mauprovince in 1993, local institutions were able to fulfill their functions because budgetresources created a common interest in forest conservation among local organizations andresidents. Moreover, the new Land Law of 1993 permitted households to sell or lease landuse rights. This affected forest conservation because preserving trees was a preconditionif a household wanted lawfully to sell or lease their land. The increase in forest area inNgoc Hien district was the result of formal institutions reducing the transaction costs oflocal organizations and residents.