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Non-timber forest products of east Kalimantan: Potentials for sustainable forest use

Non-timber forest products of east Kalimantan: Potentials for sustainable forest use
Johannes Leonardus Cornelis Hendrikus Van Valkenburg


C.T. de Wit Graduate School for Production Ecology and Resource Conservation, Wageningen University, 6708 PB Wageningen, THE NETHERLANDS.


The area of primary tropical rain forests is declining at an alarming rate. Public awareness grows that at least part of this irreplaceable biodiversity treasure should be safeguarded for future generations. It is increasingly acknowledged that sustainable extraction of Non Timber Forest Products (NTFP) can play an important role in conservation and development of these areas. The present study on NTFP in East Kalimantan was concentrated in three areas: the Wanariset research station and surroundings in the coastal area between Balikpapan and Samarinda, the P.T. ITCI concession northwest of Balikpapan, and the vicinity of the village Long Sungai Barang in the Apo Kayan close to the Sarawak border.

In Chapter 1 a brief historical overview of the economic importance ofNTFP in SouthEast Asia is given. In the present study the term NTFP comprises only products of indigenous plants, which predominantly grow in primary forest, whereby the products included are confined to non-wood products. The aims of the present study are enumerated and the motivation for choosing the various research sites is given.

The aims can be summarized as follows:

- To provide an inventory of commercially important Non Timber Forest Products in selected parts of East Kalimantan, and to evaluate their economic potential.
- To compare distribution and abundance ofNTFP in various areas in East Kalimantan.
- To study the effects of logging on species composition and abundance of NTFP.
- To contribute basic data, needed for establishing guidelines for sustainable management of the NTFP resource.

The research sites were selected to study the effects of extraction and disturbance on the NTFP resource. Therefore, areas with a traditional land use, with no influence of commercial extraction, as well as areas with various levels of disturbance and commercial extraction were chosen.

In Chapter 2 a description of the study sites, and general information on the research plots is given. Furthermore, the forest of the three research sites is compared with respect to species composition and abundance of species, genera, and families of trees. In permanent plots all trees with a dbh over l O cm were measured and mapped. The forests in the three sites are also compared by using the Importance Value Index (l.V.) of Cottam and Curtis (1956). The l.V. of a taxon (species, genus, family) consists of the sum of relative density, relative dominance and relative frequency. The species diversity as found in the Apo Kayan plots is the highest so far recorded for Indonesia. In all the research sites the importance of Dipterocarpaceae is beyond dispute and Shorea can be considered the dominant genus. However, the heterogeneity of the forest in all sites is evident and differences in species composition and especially dominance of individual species between the sites are great.

In Chapter 3 an account of species composition and abundance of various end-use categories of NTFP in primary and logged-over forest in the research sites in East Kalimantan is given. The importance of these NTFP is compared with the timber species present. Tree species yielding edible fruits account for 8 to 19 percent of all tree species, with lowest value (8 % ) in the most heavily logged ITCI plot. Of the commercial fruit species all Garcinia and Mangifera species are absent in the logged-over plots. For the Apo Kayan, the local Kenyah classification of tree species i s compared with the use according the list of PROSEA (Jansen et al., 1991). Furthermore, the economically important harvesting of gaharu wood (Aquilaria spp.) and the potential of Shorea species yielding illipe nuts (containing a commercial edible fat) is discussed.

Because of the importance in local and regional trade, fruit trees receive special attention. In Chapter 4 an account of indigenous fruit species encountered in natural forest, home gardens and local and urban markets is given. The major markets of Samarinda were surveyed twice weekly for three years (two and a half years, thereby covering three major fruiting seasons), to study species on sale and seasonality of supply. Many important indigenous fruit species showed distinct bumper years. This effect of bumper years is buffered in the markets of Samarinda. Still the absence of Baccaurea macrocarpa, Baccaurea pyriformis and Dimocarpus longan in 1993 and the overall smaller volume of indigenous fruits on sale can be explained by an absence of abundant fruiting in upriver source areas. A visit to home gardens in villages of various ethnic groups revealed that ethnic background influences the species composition of fruit trees planted. Artocarpus integer, a widely appreciated species with good market value, is neither planted nor consumed by the Lepo Tukung Kenyah of Long Sungai Barang. Baccaurea macrocarpa, Dimocarpus longan, Mangifera pajang and Nephelium ramboutan-ake are the fruit species equally favoured by Tundjung and Kenyah Dayak, but not planted by Javanese transmigrants. The constraints and possibilities for future development of potential species is discussed.

Ecological and economic aspects of the rattan resource, the economically most important NTFP, are discussed in Chapters 5 and 6. The inventory and assessment of its potential required new inventory techniques different from the methods used for tree species. Differences in the geographical distribution of species are apparent, as well as the influence of disturbance and moisture regime. Three new species were described (Van Valkenburg, 1995) that had a limited distribution, thereby confirming the rather high degree of endemism in rattan (Dransfield, 1992a, 1992b). Local variation in abundance of rattan was observed throughout East Kalimantan and is further illustrated by the results of a line survey in the Apo Kayan. The average abundance was 362 mature plants and 902 mature canes per hectare, but variation ranged from 0 plants to 18 plants with 79 mature canes per 200 m2. Growth of the rattan plants was monitored over a time span of 24 months. Natural as well as man-induced disturbance significantly (p < 0.05) increased the recruitment of rattan plants in the research plots. However, logged-over forest does not necessarily show an accelerated growth at any point in time. Furthermore, the logging as such results in great damage to the rattan population and the soil compaction impedes the establishment of seedlings. A maximum harvesting experiment on clumps of three (potentially) commercial species (Calamus javensis, C. ornatus and Daemonorops sabut) revealed differences between these species that might be an indication for a different survival strategy. Aspects of trade, ranging from species traded, prices and processing of canes, both in former times and at present are described. Important rattan trade names have been linked to botanical species, many of which unknown to be of commercial importance. The volume and value of standing stock as found in the present study, calculated at US$ 5 - 15 (-25) ha-1, indicates that vast areas of permanent forest land are required to safeguard the future supply of rattan for the Indonesian rattan industry. The employment of almost 1 million Indonesians depends on the rattan resource.

In Chapter 7, the ecological, economic and social aspects of NTFP extraction in general are discussed. Furthermore, important present land uses in East Kalimantan are compared with respect to ecological and economic aspects. After discussing the potential for development of the various NTFPs in East Kalimantan, some management options are proposed. If short-term economic gain at local level is a guideline for landuse planning then the extraction of NTFPs from primary forest areas in East Kalimantan is not the economically most competitive land use. However, the direct financial return of multiple extraction forestry at a Net Annual Income of up to US$ 46 ha-1, points to the economic feasibility of this land use and if environmental costs are taken into account it is by far the best long-term economic land use for Indonesia. As logging concessions have already been granted and vast areas consist of logged-over forest, the best possible land use for these areas should be contemplated. These logged-over forests, preserved as permanent forest estate, could be used to boost the production of (large-diameter) rattan and illipe. The high labour input required for harvesting and processing is especially important for employment in rural areas. Apart from these commercial forest estates, the potential for enrichment planting in disturbed habitats involving local populations appears promising. The traditional agroforestry systems could well be improved or even expanded by including impoverished logged-over areas.