SOIL AS A FUNDAMENTAL ELEMENT OF SILVICULTURE FOR SUSTAINABLE TROPICAL RAIN FOREST MANAGEMENT

Abstract. Soil is a fundamental element of a forest ecosystem. It provides physical support for plants, absorbs and retains water, retains and supplies essential nutrients and other chemical compounds for plant growth, and provides nutrients cycling services and habitats for organisms. Soils underlying tropical rainforest ecosystems have distintive characteristics. Thesoils are old and highly-weathered and leached, highly-acidic, lacking of weatherable mineralsand nutrient reserves, and dominated by low-activity clays with poor retention capacity tonutrients. Under such conditions, rainforest productivity relies heavily on the top layer of thesoils, consisting of decaying plant materials and animal remains in which most biologicalactivities such as nutrient cycling occur. These characteristics indicate that rainforest ecosystem is very fragile. When the forest trees overlying such soils are cut down, the logged over areas lose this thick layer and then the forest will seriously degrade. Therefore maintaining vegetation on soil surface is imperative. This paper aims to discuss properties ofsoils in the tropical rainforests, to identify soil-related damages due to silvicultural practices,and to find preventive and currative actions in order to promote sustainable tropical rainforest management