Mauro S. Reis
Tropical Forest Resources, Minas Gerais, Brazil
The economic and social importance of non-wood forest products (NWFPs) for tropical countries is well-known (Chandrasekharan and Frisk, 1994; de Beer and McDermott, 1989; FAO, 1983a, 1988, 1990, 1991b, 1993c, 1994a; Gupta and Guleria, 1982; Myers, 1988). Myers (1988) calculated that a tropical forest tract of 500 square km could, with effective management, "produce a self-renewing crop of wildlife with a potential value slightly more than US$ 200 per ha," compared to revenue of just over US$ 150/ha from commercial logging in the same area. Peters et al. (1989), in an effort to illustrate the values of NWFPs, presented data on inventory, production and current market value for all commercial tree species occurring in one ha of Amazonian forest, including wood and NWFP resources. They arrive at a combined net present value (NPV) of US$ 6,820 for a fruit and latex production and selective cutting project, with logging contributing just 7 percent of the total. This compares favourably with an estimated NPV of US$ 3,183 obtained from a 1.0-ha plantation of Gmelina arborea for pulpwood in Brazilian Amazonia and an NPV of US$ 2,960 for fully stocked cattle pastures in Brazil. In India, the collection and processing of the leaves of the tendu tree (Diospyros melanoxylon), used to wrap small cheroots known as "bidi", produces an estimated US$ 200 million (FAO, 1994c) and provides part-time employment for up to half a million women. Indonesia earned US$ 200 million in foreign exchange from NWFPs in 1982 (Gillis, 1986).
In the Amazonia of Peru and Brazil, more than 1.8 million people derive a significant portion of their income from extractive forests, mainly of Brazil nut (Bertholletia excelsa) and rubber trees (Hevea brasiliensis). Near Xapuri, Brazil this earns an average annual income of US$ 960 per family.
An estimated 80 percent of the plant species providing NWFPs are found only in the biological richness and ecological complexity of primary forests. Some of them can only thrive within natural habitat and do not lend themselves to domestication. On the other hand, even species that can be grown in plantations depend heavily on regular infusions of germplasm from wild gene reservoirs (e.g. cacao, Theobroma cacao). Other than wood trees, forest species also represent a wild gene-pool, which are a safety net for narrowly based industrial agriculture.
NWFPs are being depleted at an unprecedent rate due to increasing human population pressure and demand. Each year, an estimated 15.4 million ha of tropical forests and woodlands are destroyed or seriously degraded, principally through agricultural expansion, uncontrolled livestock grazing, logging, and fuelwood collection (WRI/IIED 1988, FAO 1993a).
Therefore it has never been more urgent to realise the full potential of NWFP resources for sustainable development, both in terms of meeting immediate and future needs of increasing populations, and of the continuity of the natural resource base itself. However, the long-term survival of NWFP resources depends on the development of successful strategies to meet the economic needs of people while maintaining biological diversity. The appropriate management and conservation of NWFP resources, either in natural forest or in plantations is, therefore, of fundamental importance as part of these strategies. This paper discuss and analyses some relevant aspects of development of NWFP resources, with emphasis on: (1) types and characteristics of NWFP resources; (2) aspects related to the management of NWFPs; (3) factors influencing sustainability of resources; (4) nature and severity of different constraints affecting resource sustainability and development; and (5) management guidelines.
NWFPs are derived from a variety of sources: plants (trees, shrubs, herbs, grasses, palms), animals (insects, birds, reptiles, large animals), and a range of others. From plants alone, many different parts (e.g. roots, stems, barks, leaves, flowers, seeds, fruits) often provide different products simultaneously and/or at different times. Furthermore, NWFPs exhibit considerable variation in their use, with some consumed immediately on harvest (e.g. fruits, fodder, wild meat), others after primary processing (e.g. edible nuts, bamboo and rattans products), and still others proceeding through a series of downstream processing to meet market specifications (e.g. phyto-chemicals, food additives and flavourings).
An exhaustive list could number thousands and range from exudates (gums, resins and oleo-resins) to palms (rattan); from edible nuts, fruits and vegetables to mushrooms and spices; from meat and by-products from game animals including mammals, fowl, reptiles and fish to the animals themselves for the pet and zoo; from fodder to biochemically-active plants for diverse pharmaceutical and medicinal uses.
Also, differences in habitat lead to regional and even local variation in NWFP resources. The NWFP resources important for a locality would generally fall within a manageable number. In spite of this, however, the range of activities related to their production, management and conservation, processing and marketing is highly complex, requiring adequate technology, support infrastructure, research facilities and skilled manpower.
Many descriptive accounts of NWFP resources have been published ? for Asia (e.g. Aksornkoae et al. 1992; FAO, 1994a; Gupta and Guleria, 1982; Mann and Saxena, 1980; Nair, 1990; Revilla et al., 1990), Africa (Chandrasekharan, 1993; Cunninghan and Mbenkum, 1993; Campbell and Brigham, 1993; Murindagomo, 1992; Poulsen, 1981), Latin America and the Caribbean (Chandrasekharan and Frisk, 1994; Clay and Clement, 1993; Gentry, 1988; Petersen and Balslev, 1990; O'Hara, 1994), and global use (FAO, 1983b, 1988, 1993a, 1993b, 1994b; ITTO, 1993; Menon, 1989; Saenger et al., 1983). Readers are referred to these publications for detailed information on NWFP resources. See the theme paper by Chandrasekharan for a discussion of classification of NWFPs.
Many of the plants providing NWFPs are found only among the biological richness and ecological complexity of primary forests. Some of them can only thrive within their natural habitat and do not lend themselves to domestication of any sort. However, many NWFP species can be domesticated.
Domestication of plants yielding NWFPs, involving their genetic improvement and cultivation under intensive practises, is often considered a means of ensuring economic success of growing ventures. Experience has shown that once a NWFP achieves commercial importance, its supply from wild sources tends to be replaced by cultivated sources in order to bring production, quality and supply of raw material and cost under control. In fact, being nature-based, NWFPs can never be totally uniform in their characteristics, nor can their supply be as regular and reliable as plantation-based products. There is therefore a tendency to move towards plantation-based production of NWFPs whenever potential markets become large and attractive enough and plantation production is found to be feasible.
In respect to wild plants providing NWFPs, production in most cases is seasonal; other nature-determined conditions can affect both the quantity and quality of the products. It also means that the production can vary considerably from year to year and from location to location. Consequently the availability of products can vary. From the marketing point of view, this is one of the major disadvantages because many customers tend to prefer sustained and secure supplies of even-quality products.
Intensive cultivation of NWFP resources take place under monoculture, mixed cropping, and agroforestry systems or under special conditions. Certain NWFP plants (such as Elettaria cardamomum ? cardamum, in Guatemala, Honduras and Costa Rica), can be grown under the shade of natural or man-made forests. Many kinds of mushrooms that are important in trade can only grow in very particular habitats under a narrow range of ecological conditions and micro-climates. Examples are the "black mushrooms" or morels (Morchellus spp.), which are widely gathered in wooded areas of north-central Pakistan and traded internationally in large quantities. Other kinds of mushrooms can be cultivated or semi-cultivated in compost derived from their natural habitat. In Bhutan, for example, four kinds of oyster mushrooms (Ostreu species) are grown in year-round rotation on forest logs injected with fungal spores or in compost mixtures made from forest litter.
Domesticated NWFP species in agroforestry systems provide continuous tree cover and offer a number of advantages:
In parts of the Philippines, where natural rattan palm supply has been exhausted, nurseries are now being established to provide stock to plant out in the forest. In this case, the growth and "monetization" of the market for the natural product appears to be in the process of converting it from a wild product into a crop. Much the same process may have led to the development of other NWFPs into staple crops in the past. Bamboos are now routinely plantation-grown but, while they can be grown in the forest without the additional expense of owning or renting the land they grown on, like rattan, they are likely to remain a predominantly wild or semi-cultivated crop for many years to come.
The susceptibility of NWFP plantations, mainly in monoculture, to pests and diseases caused by insects and fungi, is one of the disadvantages of domestication. In fact, once a plant species is planted outside its natural habitat (the case of most domesticated species providing NWFPs), its susceptibility to pests and diseases increases, in some cases drastically. This can result in the need for extensive use of pesticides which may cause environmental problems. For example, plantations of Elaeis guineensis in South America would become heavily infested because many native palms harbour pest populations (Pedersen and Balslev, 1990).
Also, monocultures of domesticated species that replace natural forests result in loss of biological diversity, and intense cultivation of a single plant species rapidly depletes soil nutrient reserves.
Domesticated species that can be grown in plantations, or as pure or mixed crops, are heavily dependent on regular infusion of germplasm from wild gene reservoirs (e.g. cacao and pimenta). Consequently, only the continued existence of species variability in the wild will afford plant breeders a chance for creating, for example, new disease-resistant and high-yielding varieties.
Appropriately selected NWFP components in an integrated land use can contribute to both the productivity and sustainability of farming systems on marginal land in several ways: by enhancing the production of organic matter; by maintaining soil fertility; by reducing erosion; by conserving water and by creating a more favourable microclimate for associated crops and livestock. These service roles are in addition to direct production roles. Thus they can help supply food, fodder, fuelwood, building material and other raw materials for rural industries and provide new habitat for wildlife. In traditional, integrated land-use practices, NWFP trees and shrubs are also important in maximizing and diversifying the productivity of even highly fertile lands. In this respect, agroforestry systems are very important and are most commonly found in areas with a long history of population pressure, indicating their general efficiency as environmentally sound land-use systems. Whether on marginal or highly productive lands, diversified agroforestry systems may be the most appropriate land use where land tenure constraints, lack of marketing infrastructure or an unfavourable political economy make it imperative for small landholders to reduce risks and satisfy most of their basic needs directly from the land resources under their control (Lundgren and Raintree, 1983).
Plant species providing NWFPs have been used as components of integrated land-use practices with excellent results. For example, the association of naturally occurring Faidherbia albida (formerly Acacia albida) with dryland grain crops in the Sahel zone and some parts of East Africa where yields of crops grown in proximity to trees can be double those of crops grown in the open (Mann and Saxena, 1980). Some interesting aspects are: nitrogen fixation, microclimatic benefits and the peculiar "reserve phenology" of the trees (which leafs out in the dry season and drops its leaves at the beginning of the rainy season, thus nicely accommodating the requirements of crop cultivation). The pods of F. albida trees produced in the dry season are excellent fodder for livestock that gather under the shade of the trees. Similar results are reported for Prosopsis cineraria/cereal associations in eastern Rajasthan, India. P. cineraria trees are lopped annually for the highly valued fodder.
Soil salinization and related phenomena are the most serious problems threatening land productivity in arid and semi-arid regions. Of considerable relevance, however, to the forest-food interaction are those cases in non-irrigated lands where removal of NWFP-producing trees has created saline streams and soils both on and off site.
In Sudan, gum arabic (Acacia senegal) areas are mostly sandy, unstable and highly vulnerable to erosion. A. senegal trees help to increase agricultural production either by protecting soil and crops or by improving and adding to soil fertility. The pattern of land use within villages is one of current cultivation and fallow on which there may be A. senegal plantations. The system is basically a variation of shifting cultivation and traditionally consists of about four years of cropping followed by a period of 10 to 14 years of fallow under regenerated A. senegal. The fallow period rests the soil and the regenerated trees protect it from wind erosion. The trees also naturally improve soil because they fix nitrogen and add phosphorus, ammonium nitrates and organic matter. The system is rather stable in areas of low population densities.
Multipurpose NWFP trees, particularly nitrogen-fixing and pod-producing species so well adapted to dryland conditions, can be grown at interstitial locations on the farm or in association with crops without replacing them. A prominent NWFP species in the semi-arid Northeastern Brazil used for integrated land use is Prosopsis julifora. It resists drought without losing any of its leaves during the long dry season; has high nutritional value, specially its leaves, pods and fruits, which are good animal fodder and source of foods; and is effective against erosion and desertification, and in dune stabilization, reclamation of salinized soils and as support for apiculture (FAO, 1988 and author's personal observation).
Trees providing NWFPs are important land-use components and have been extensively planted by small landholders as an outgrowth of shifting cultivation in many parts of the world. Notable are the oil palm, cacao, coffee and cola plantations of West Africa (Getahun et al., 1982) and the coconut, rubber, oil palm, cacao and coffee plantations of smallholders in Southeast Asia (Dove, 1983). Similar land uses incorporating NWFP species have been used in Latin America and they have provided a sound economic and environmental combination. In Asia and the Pacific, coconut palm is an important land-use component for smallholders and plantations alike.
Integrated land use incorporating NWFP species is also important as a means of providing new habitat for wildlife. For example, the presence of several rows of trees in an otherwise "open" landscape of grasslands or annual or perennial crops provides often one or more of the essential habitat requirements of one or more wildlife species. The windbreak itself may provide a source of food, particularly fruits, seeds or insects for birds and small mammals. In Zimbabwe, wildlife is an important component of land use. About 2.7 million ha of commercial farmland (around 22 percent of the country) is devoted to wildlife production, sometimes in conjunction with livestock (Campbell and Brigham, 1993).
The facet that tropical forests are ecologically complex and biologically diverse ecosystems, has two implications: (1) they should be put under multiple-use management to benefit from their great variety of products and services; (2) they should be managed with sustainability as an explicit and prominent objective, owing to the complex interdependencies among species and their vulnerability to irreversible degradation. Managing tropical forests only for wood to the exclusion of NWFPs will fail to maximize the social value of the scarce resource and to ensure its sustainability over time.
Although the great potential for managing NWFP resources on a sustained-yield basis has been frequently emphasized (e.g. Schimidt, 1987; Fearnside, 1989; Allegretti, 1990; Peters, 1990; ITTO 1991; FAO, 1989b, 1989c, and 1993a), rarely has this objective actually been achieved. This situation is primarily due to the lack of concerted effort to manage NWFP resources, to conduct suitable inventory of the resources to be managed, to ensure their regeneration in the forest, or even to broadly define a sustainable level of harvest. Regardless of existing markets or land-tenure systems, maintaining a continual supply of harvestable resources from a tropical forest requires management. This section discusses some important aspects related to the management of NWFP resources.
One of the major problem widely recognised by forest researchers in implementing sustainable management of NWFP resources is the lack of quantitative information related to the resource.
An FAO forest resources assessment of 1990 noted the depressing state of forest inventory in the tropics. Three of the 90 countries included in the study have never carried out a forest inventory; 39 countries had carried out one assessment prior to 1980; 27 countries had carried out one assessment between 1981 and 1990; and only 21 had carried out more than one assessment (thus allowing for minimum levels of "monitoring", even as regards the status of commercial wood supplies). Twenty-five of the countries had some kind of (mainly quantitative) inventory/assessment information on conservation areas and management of forest resources (FAO, 1993a). The situation is still worse for inventory/assessment of NWFP resources: no country had carried out a complete assessment on the status of NWFP resources.
Inventory of NWFP resources involves extensive fieldwork and the counting and measuring of plants. The objective of these activities is to answer several basic questions about the nature and extent of the forest resource base. For example, what economic plant species are found within the management area- What products do they produce? How abundant are they, and do they appear to be maintaining themselves in the forest? Which of these resources are restricted to a particular forest type, and which are more evenly distributed throughout the site? What plant resources have the highest potential for sustained-yield management? Addressing these questions requires data from a quantitative forest inventory. Inventory/assessment data represents the core of all management operations.
Researchers have developed a wide variety of inventory techniques (for details about forestry inventory techniques and procedures, see Adlard, 1990; FAO, 1981; and Avery, 1983). The selection of an appropriate sampling scheme for forestry inventory ultimately depends on the capabilities and experience of local field workers, the conditions in the forest, and the personal preferences of the resource manager. Wood (1989) reports that out of 36 tropical countries surveyed, fixed-area plots are more frequently used (44 percent) than transects (34 percent). Systematic sampling is the preferred design in Africa and Southeast Asia, while random sampling is more strongly favoured in Latin America. Systemic transects would seem to be the preferred inventory method for NWFP resources. This method presents relatively low probability for errors in locating of the sample unit, and also provides good opportunity to map and refine the initial forest typology. Transect widths of either 10 or 20 m are recommendable in most situations, the smaller 10 m transects being most appropriate in more homogeneous forests.
Two important aspects that have to be considered when designing an inventory for NWFP resources are: (1) the lower diameter limit of measurement of the trees and plants providing NWFPs and (2) the overall sampling intensity. A lower diameter limit of 20 to 40 to 60 cm diameter at breast height (DBH) have been used in different inventories. The problem, however, is that many forest species (e.g. medicinal plants, fruit trees) are mid-canopy or understorey species that may never attain a diameter of magnitude and consequently would be completely missed by such an inventory. A smaller minimum diameter limit is therefore necessary for NWFP resources.
The overall sampling intensity required in a forest inventory is governed by the variability of the forest, allowable inventory costs, and the desired standard of precision (Avery, 1983). For all of this, appropriate inventory techniques have to be adjusted to the specific characteristics of the NWFP resources to be managed.
In an inventory, field procedures and measurements are important. The field procedures for each plot or transect are essentially the same. Each sample tree should have its taxonomic identity and local name determined, its ethnobotanical or use information and size recorded. Detailed botanical surveys of NWFP resources (e.g. medicinal plants) based on the analysis of voucher specimens have shown that a single vernacular name may frequently refer to several different taxa (Gentry, 1988). Ethnobotanical or use information about NWFP resources should be as detailed and specific as possible, and should not be restricted to the primary or current commercial use of the resource. For example, for those species providing specific and/or multiple products, NWFP information should consider all parts of the resource (e.g. bark and leaves may be used medicinally, seeds may contain a valuable oil, stem may produce gum and the fruits may be used as food). This provides an estimate of the overall resource "richness" of the forest and will later serve as baseline criteria for selecting the specific resources to be managed. It also provides information on the different possible harvest techniques.
Unlike commercial forestry inventories, in which the volume of wood and number of logs are critical variables, the measurement of tree height is not essential in an inventory for most NWFP resources. However, this procedure is justified for some selected vegetative tissues of extreme commercial value (e.g. rattan and nipa palms). Also, additional measurements may be necessary depending on the nature of the NWFP resource being sampled (e.g. bark thickness measurement of Litsea spp., and increment measurement of cores to check for the presence of gharu wood in Aquilaria trees).
As mentioned before, information is very scarce on inventory of NWFP resources. Bamboo is probably an exception. A suitable inventory methodology for bamboo and rattan palm resources has been developed in the Philippines by the International Development Research Centre. Inventory for the enumeration of rattan palm resources is also being developed by the Kerala Forest Research Institute in India (Menon, 1989).
An inventory model, field sampling procedure, and data forms are reported for sagu (Metroxylon spp.) and nipa palm (Nypa fruticana) in Indonesia (Reville et al., 1990). Those authors suggest that sagu be enumerated within the same 10-m radius plot used to sample rattan (with 3-m and longer stem) and bamboo. For nipa, 2-m radius plot is adequate to sample the seedlings (not more than 1.5 m tall), while a 5-m radius plot would be needed for larger nipa plants. Additional information in the 10-m radius plot should be recorded, such as varieties of sagu species (three species of sagu have been observed in India), clump number and diameter, total number of stems including the young and overmature, maturity classes (one of five maturity classes shall be identified for each sagu plant), girth measurement, stem height or bole length, damage on a sagu tree and sagu yield (in kg of partially dried extract).
Inventories for a number of NWFP resources have been carried out in small areas and/or in experimental plots, e.g. assai palm (Euterpe spp.), which occurs in the Amazonia region of South America. An inventory of E. oleracea in the Amazon river estuary has shown that on average, the plant population is between 230 and 600 clumps/ha, considering only clumps with stems higher than 2 m. Total population ranges from 2.5 to 7.5 plants/ha, most of them (50 percent) in the first seedlings stage (one to two leaves and about 20 to 25 cm tall). Population density of E. precatoria varies from 50 to 250 plants/ha in the forest ecosystems of Peruvian Amazonia (Kahn, 1988). Higher population densities were found in Manaquiri, Amazonas, Brazil. Inventory data showed population densities varying from 5,740 to 13,396 plants/ha.
The term conservation area has been defined as "an area of land managed through legal or customary regimes so as to protect and maintain biological diversity and natural and associated cultural resources". (This definition was agreed at the Fourth World Congress on National Parks and Protected Areas, Caracas, 10-12 February 1992.)
The FAO forest assessment of 1993 reports that an estimated area of 212.9 million ha in forestry and 371.7 million ha in wildlife are under management for conservation in Asia and the Pacific, Africa and Latin America and the Caribbean regions. However, none of the areas under management for conservation have been established primarily for the maintenance and sustainability of NWFP resources. Also, it is often impossible to know whether or not a conservation area network is representative, particulary in terms of biological diversity. A special survey conducted by WCMC shows that out of 8,715 conservation areas, only 5 percent are known to have been inventoried for one or more taxonomic groups (FAO, 1993a). Conservation areas covered 1.5 percent of the total land area (0.3 percent in Africa, 3.0 percent in Asia/Pacific and 1.3 percent in Latin America and the Caribbean). Protection forests (mainly set aside for watershed protection), covered 3 percent of the land area in the tropical countries. Tropical forests reportedly under forest management regimes covered less than 5 percent in 1980 (FAO, 1982). Although a corresponding figure for 1990 was not recorded, the area under management is unlikely to have increased. The widespread lack of forest management is highly disturbing, also from the point of view of conservation of genetic and biological diversity of NWFP species presently used and other species growing in association with them.
Despite the fact that existing conservation areas have frequently been established with little or no regard to ecological criteria for their selection, they can be considered important for the protection of NWFP resources. Their proper management can support conservation of genetic wealth and variability of NWFP resources. Notwithstanding the potential benefits from the use of NWFPs and the enormous extent to which they are already used throughout the tropics, it has proved very difficult to find ways in which the NWFP sector can be further developed as a prime force for forest conservation. However, effort should be made at country and regional levels in order to establish conservation areas primarily for the maintenance and sustainability of the existing NWFP resources.
According to the FAO (1993) definition, "Sustainable forest management will ensure that the values derived from the forest meet present-day needs while at the same time ensuring their continued availability and contributions to long-term development needs." Forest management, however, does not comprise everything desirable that might be done but is rather a matter of selecting and prioritizing the tasks that can and should be carried out for a particular area (Bramble, 1987).
It is important to understand that conservation of NWFP resources through management is not the same as preservation through protection or a policy of non-interference. In neither case can alteration be prevented. Ecosystems will continue to change even if left completely untouched by humankind. Management intervention in a forest, no matter how carefully or lightly carried out, inevitably alters the structure and ecology more quickly and in different directions than a policy of preservation; if poorly carried out, it runs the risk of causing serious and permanent damage.
NWFP resources, if properly managed, will play a vital role in human welfare and development in the coming decades. In fact, this is already demonstrated by a number of projects which aim to conserve areas of rainforests of outstanding importance for biological diversity. Conservation through more rational use of NWFPs and their protection is reported by Sayer (1991). (Examples are given, elsewhere in this paper, of areas being managed for the conservation of genetic resources of species providing NWFPs and biological diversity.)
An important component of NWFP resources is wildlife. Wildlife is now generally recognised as a renewable natural resource, but unfortunately it is rarely managed to this end. Certainly, conservation of endangered species is an essential part of wildlife management, and where species have been over-exploited, preservation of these animals through protection in national parks or other rigidly controlled areas may be the only practical solution to ensure survival. But protection must be viewed as a means to an end and not an end in itself. As with other renewable natural resources, including forests and wooded areas that are the primary habitat for wild animals, the key to long-term conservation of wildlife and of biological diversity is management based on the concept of sustainable utilization. Sustainable management is particularly important in view of the role of wildlife resources as a source of food and income for rural people.
In regions where growing population pressures are leading to intensive land use, captive or semi-captive rearing of wildlife for food and other products is taking an increasing importance. FAO (1990) provides examples of wild animals successfully managed for food, either in isolation or integrated into existing agricultural systems. Some individual countries have made important progress in confronting the challenges of wildlife management, in cooperation with international organisations. FAO has assisted India, Papua New Guinea and Ethiopia to ensure the conservation of crocodile resources and promote their management and sustained utilization. Also, in Latin America technical cooperation network on national parks and other conservation areas is being implemented with the assistance of FAO. It aims to ensure conservation and management of wildlife resources such as capybara, crocodiles (Caiman crocodilus), and river turtle (Podocnemis spp).
Integrated Management for Wood and NWFPs in Natural Forests
Forest management for wood production implies "controlled applications of harvesting regulations, complemented by appropriate silvicultural and protective measures designed to maintain and improve the productivity of the forests." Since 1980 a number of intensive studies on forest management have been carried out by FAO and the International Tropical Timber Organization (ITTO). ITTO made detailed investigations on the current status of forest management and presented them in several volumes by continent. FORIS database has collected information on a country basis.
In general, tropical forest management for more than a century has been geared for wood production. Silvicultural systems for enhancing the growth of non-wood resources in forests, such as wild fruits, edible nuts, mushrooms, gums and latex which can be harvested non-destructively and in combination with timber, have received much less attention. In recent years, however, the concept of forest management has expanded to include NWFPs, and national forest agencies are working to adapt their management to address this.
Generally speaking, we can say that integrated multipurpose management of forests for wood and NWFPs is highly demanding on scientific knowledge and technology. It involves, in addition to the essential tools of management for wood production, defining objectives as mentioned before, detailed investigation and prospecting of NWFP resources for different products. These investigations have to consider:
The complexity of integrated management of forests for wood and non-wood forest products suggest the need for appropriately balanced and integrated systems, combining ecological and economic prudence. These systems should consider that trees and plants yielding wood and non-wood products can co-exist in the forest, and indeed many non-wood products are available from timber species. Therefore harvesting of wood and non-wood products is not mutually exclusive, but it requires great care. Wood harvesting, if improperly done, can be destructive of NWFPs; likewise management of some NWFPs may substantially affect production of others.
Integrated management of forests for wood and non-wood products and services can be an essential strategy. In 1984 Norman Myers proposed the creation of "industrial forests"; in 1993 Clay and Clement preferred the term "income-generating forests". Such forests are designed to conserve or enhance biological diversity while exploiting the economically useful fraction of this diversity. In Myers' conception, an income-generating forest would contain a large number of economic species with an equal or larger number of industrial uses, as well as an even larger number of species with no known current use. Myers suggested that species producing latex, resins, gums, oils, essential oils, alkaloids, or medicinal products could form the basis for these forests. This concept of income-generating forests is, in fact the concept of integrated management of wood and NWFP resources.
Important aspects to be considered in integrated management of forests related to the knowledge both of wood-producing trees and the NWFP resources; for example, the type of products produced by particular species, the measurement of productivity, and the sampling procedures to be used in field studies.
The type of product(s) produced by particular species can have a major influence on its potential for sustainable exploitation and management. Harvests of bark, stem tissue and roots almost invariably kill the plant, and, as is the case with wood, sustainability can only be achieved by ensuring that the death of every adult tree is replaced by growth of another. Unfortunately, maintaining continual recruitment of a desirable species when the seed-producers in the population are being routinely eliminated can be an extremely difficult and expensive proposition. The harvest of latex, fruits, oil seeds and leaf tissues, on the other hand, do not necessarily kill the adult tree or alter the initial size-class distribution of the population.
Measurement of plant population productivity is different when the target is to manage wood and NWFP species. For wood, this information is collected by monitoring the radial increment of trees. There is a large and detailed literature on the growth and yield characteristics of commercial wood species. However, for NWFP species virtually nothing is known about fruit, oil seed, latex and resin yield. Just as foresters use growth data to avoid cutting timber at a faster rate than that which is produced by the forest, the sustained-yield management of NWFP resources also requires a knowledge of the productive capacity of the species being exploited. That this knowledge is frequently lacking sheds some doubt on the long-term viability of many current efforts to promote increased utilization of NWFP resources.
Sampling procedures used in the yield studies is another important aspect of managing wood and NWFP resources. These will vary with the type of NWFP species being measured. Three main groups are recognised for NWFP species based on the origin of the plant tissue or ingredients of value: reproductive propagules, plant exudates and vegetative tissues. Although fruit, nuts and oil seeds are different commodities, their production by individual trees can be measured using a similar methodological approach. Reproductive propagules, plant exudates and vegetative tissues will require different sampling procedures. For example, the production of reproductive propagules is measured at discrete intervals throughout the fruiting season, using either direct counts or a random sample of the area under the crown of adult trees. For small trees that produce few fruits of large size (e.g. certain palms and cauliflorous trees), direct counts may be employed with reasonable precision. Direct counts have been used successfully to estimate fruit production in a number of ecological studies (Sork, 1987; Peters and Hammond, 1990). Tall forest trees that produce more fruit than can be counted individually (e.g. most commercial fruits, nuts and oil seeds, which are relatively large and heavy) must be sampled using small plots or specially constructed fruit traps.
The measurement of plant exudate yield requires some a priori knowledge of the traditional tapping techniques used with that species. Information on the frequency of tapping is particularly important. Depending on the tapping regime employed, daily, weekly, or monthly production rates are then calculated for each sample tree and exudate type under study.
The variety of plant parts exploited (e.g. stems, leaves, bark, roots and apical buds) can be divided into two groups, based on the physiological response of a plant species to harvesting: (1) where the tissue extracted is naturally regenerated (e.g. leaves and the bark and apical buds of certain species), or (2) where the plant is killed by harvesting (e.g. most types of stem tissue, roots and bark). Different sampling methodologies are required to estimate the productivity of these two groups. In South-Central Chile, for example, the primary productivity of two bamboo species, Chusquea culeon and C. tenuiflora, was measured through a study of biomass and dry-matter production of culm and foliage. Net primary production of standing crop above-ground was estimated for a pure stand of C. culeon, and standing crop for C. tenuiflora in the understorey of a mixed Nothofagua betuloides-N. pumillo forest near the timberline at 1,040 m in the Andes (see Veblen et al. (1980) for details on the methodology). Estimates of dry-matter yields are available for some stands of bamboo managed for paper production in several localities in Asia (Huberman, 1959 and Ueda, 1960). The same methodology developed in Chile has been applied in the Philippines for bamboo species.
Consideration should also be given to the benefits afforded by the management of multi-purpose NWFP species. Specific examples of this include species which produce both oil seeds and a valuable oleo-resin (e.g. certain species of Shorea in Southeast Asia), or those that produce edible fruits and also have leaves which are useful for cordage or thatch (e.g. numerous palm species in the Amazonia region). Management focusing on a single multiple-use species can generate two sources of revenue without the expense of monitoring the regeneration and population dynamics of two separate NWFP plant populations. Integrated management of wood and multi-use NWFP species is still more complex than management of wood and a single-use NWFP species.
All of this requires prioritization of the objectives for multipurpose management (wood vs. NWFPs) in order to facilitate selection among the conflicting demands on the forests under management. One main objective must be given priority over the others. However, in striving to achieve this objective, forest managers must see that all the other objectives are at least partially fulfilled (FAO, 1991).
One example of integrated forest management well-adapted to local socio-economic conditions is the Plan Piloto Forestal (PPF) project in Quintana Roo, Mexico. Initiated in 1983 by GTZ and the Instituto de Investigaciones Forestales, the project aimed to promote forest conservation and local development through community participation in natural forest management for wood and non-wood products. The project's first step for securing popular participation was to have logging rights assigned to the "ejidos", the local communities. The PPF then helped local forest communities to organise themselves to manage the forest in a way that would ensure they received the economic benefits. The project focused on two species: mahogany (Swietenia macrophylla) and chicle gum (Manilkara Zapota). Essentially, the PPF applied:
As outlined above, foresters have been testing, developing and refining silvicultural techniques for managing tropical forests for over 100 years. However, silvicultural systems for NWFP resources have received much less attention. Many indigenous or other local communities in the tropics have developed their own form of silviculture for managing their NWFP resources. Such indigenous or local systems of forest management have been little studied.
Many of these indigenous silvicultural systems are quite sophisticated and, not surprisingly, are comprised of many of the same operations routinely employed by trained foresters. The major difference is that these indigenous systems have yet to be formally codified or scientifically accepted as operationally valid. Both indigenous silvicultural practices and conventional forestry can contribute in designing or improving systems for managing NWFP resources on a sustainable basis (Chandrasekharan, 1993).
Conventional systems of forest management and the silvicultural treatments applied primarily for commercial timber trees have been described and discussed in numerous publications and textbooks (e.g. Schmidt, 1987; FAO, 1989b, 1989c, 1991a; Baur, 1964; Synnott, 1979; Matthews, 1989). This section emphasizes only some features of common silvicultural systems applied in the management of tropical forests.
The primary objective of any silvicultural intervention is to selectively modify the biotic and/or abiotic environment in a tropical forest to favour regeneration and growth of a restricted number of tree species (Smith, 1962). Every silvicultural system is composed of a series of individual operations or components which contribute in different ways to fulfil the overall management objective. Although their exact details vary from system to system, the most common silvicultural operations in tropical forests may be divided into seven basic groups: (1) harvesting, (2) refinement, (3) thinning, (4) liberation, (5) selective weeding, (6) diagnostic sampling, and (7) enrichment planting. The specific purpose and impact of each operation is quite distinct.
There has been a great deal of experience with the silvicultural treatment of tropical forests in Asia and Africa (Schmidt, 1987). Such experience is sorely lacking in the Amazonia region; some estimates maintain that less than 14,000 ha of forest are subjected to any type of management at all (Lanly, 1982).
The silvicultural systems which have been developed for tropical forests can be divided into two groups: polycyclic and monocyclic systems. The selective felling systems, as officially practised in Indonesia, is an example of a polycyclic silvicultural system. In these systems, the commercial trees are harvested repeatedly in a continual series of felling cycles. The length of these felling cycles is usually about half of the time required for the species to reach merchantable size. The Malaysian Uniform System and the Tropical Shelterwood System are both examples of monocyclic systems. In these systems, all of the merchantable trees are harvested in a single felling operation, with the length of the cycle more or less equal to the rotation age of the species. Polycyclic systems rely on the existing crop of seedlings, saplings and poles in the forest to produce the harvestable crop for the next felling cycle, while monocycling systems ignore the accumulated growth of these smaller size classes and rely almost entirely on new seedlings to produce the next crop of trees.
This paper does not analyze in detail each of these silvicultural systems. However, in order to compare these conventional forms of forest management with the indigenous forms of NWFP resource management, it is important to give the basic composition of the systems. The selective felling system is composed of diagnostic sampling, harvesting, weeding, and enrichment planting operations. The Malaysian Uniform System includes diagnostic sampling, harvesting, refinement, weeding and thinning. Logging is preceded by regeneration sampling and the inventory and marking of harvestable trees; harvesting is deferred if an insufficient seedling crop is encountered. The Tropical Shelterwood System is composed of diagnostic sampling, refinement, weeding, harvesting and thinning operations.
These conventional silvicultural treatment of tropical forests are generally related to commercial timber production. These treatments are effective techniques for manipulating forest structure and composition in such manner as to favour the abundance of desirable resources, including NWFP resources. The ultimate success of these techniques, however, largely depends on the particular species and site being managed.
There is no single silvicultural system that can be blindly applied in every forest. Also, experience has shown that periodic sampling of the response of the forest to individual treatments is essential for guiding and refining subsequent silvicultural operations. The most successful silvicultural systems are information-rich, and the greater the understanding of a species' ecological behaviour, the easier it is to develop a viable system of silvicultural treatment. Of greater importance in the long run is the ability of the resources manager to actually implement these activities, to change prescriptions as necessary, and to be able to withstand the pressure and encroachment from conflicting forms of land use that inevitably occur. Many of the failures of silviculture in the tropics are directly attributable to social and economic, rather than technical, constraints (Buschbacher, 1990).
Forest clearing for agriculture and intensive management of re-growth or secondary vegetation in these cleared areas is a type of agroforestry activity commonly used in shifting cultivation in the tropical forests of Asia, Africa and Latin America. In fact, most of these systems are monocyclic in nature. Its many forms and applications have been documented by many studies. The systems used by indigenous peoples are low-intensity or "polycyclic" systems and are of great interest to the present discussion.
The forms or systems adopted by indigenous peoples to manage tropical forest have been documented by only a few researchers (e.g. Chin, 1985; Gomez-Pompa et al. 1987; Posey and Balee, 1989; and Anderson, 1990). The few systems that have been studied, however, appear to exhibit several common characteristics:
The indigenous system of NWFP management developed by the Daret of Balai includes rattan palm (Calamus spp.), sugar palm (Arenga pinnata), illipe nuts (Shorea spp.), bamboo, edible fruits ? including durian (Durio zibethinus), rambutam (Nephelium spp.), langsat (Lansium domesticum), and mangosteen (Garcinia mangostana) ? and wood species like Eusideroxylon zwagerii, which produces pole for house construction. The Daret have consciously enhanced distribution and abundance of all of these resources, both wild and introduced. They have planted many fruit tree species in the managed forest, often as social rituals, e.g. to commemorate the dead (Padoch and Peters, 1992).
The essential silvicultural components of the Daret management strategy are:
The management techniques used on Ilha das Onças near the city of Belém, State of Pará, Brazil, are described by Anderson et al. (1985), Anderson and Maria Ioris (1989), and Anderson (1988 and 1990). The floodplain forests ? called varzea forest ? of eastern Amazonia of Brazil, is characterised by the dominance of the açai palm (Euterpe oleracea) of high commercial value and a variety of species providing NWFPs (e.g. fruit and latex) and wood (e.g. "andiroba" Carapa guianensis and "ucuuba" ? Virola spp.). Special attention is given to the açai palm.
The essential silvicultural components of the Ilha das Onças management strategy are:
The major differences between the indigenous management systems of Daret of Balai and Ilha das Onças are:
Earlier when discussing the complexity of integrated management of wood and NWFPs in natural forest, it was pointed out that management for wood and NWFP resources is not mutually exclusive and requires great care. In this context, harvesting should be seen as a silvicultural operation linked to the initial inventory. The most critical element in the implementation of a management plan is the degree of control and supervision exercised over harvesting operations of wood and NWFP resources. Because harvesting of NWFPs can, when improperly done, be deleterious to the resource base, any attempt to promote integrated management of NWFPs has to consider the product and its sources. Moreover, it is necessary to consider the harvest technology that should be adopted because, in many cases, the issue of sustainability of resources providing NWFPs, particularly from tropical forests, has more to do with harvesting technology than with actual levels of current off-take. For example, pau rosa (Aniba roseadora), an essential oil whose harvest has almost eliminated the species from the Amazon region, can probably be harvested sustainably. Likewise, copaíba oil (Copaífera multijuga), chicle (Manilkara zapota), and other latexes, and certain palm and fruits (e.g. Mauritia species that grow in the lowland jungles of Brazil and Peru, and buriti, or Mauritia flexuosa) can be harvested sustainably, even though they often are not. Sapodilla trees, tapped for chicle and felled for timber, have been depleted over large areas of Guatemala and Mexico. Commercial sassafras oil is manufactured by the steam distillation of the trunk wood of certain species of the Lauraceae family (Ocotea pretiosa in the Mata Atlântica region of Brazil and varieties of Cinnamomum camphora, in Southern China and Viet Nam). In each case, the industry is based on the destructive harvesting of not only wild mature trees but also juvenile trees. Concern exists, therefore, over sustainability and conservation in all these producer countries, and over the long-term availability of the resource base and consequently of sassafras oil to consumers. In general, the existing systems of harvesting and collection of NWFPs do not have adequate technological and management back-up, and its linkage to the chain of middlemen and traders is not conductive to sustainable management. Also, harvesting is a particularly weak link in the utilization of NWFPs due to the variety of tools, techniques and situations involved. Poor harvesting results in product wastage and resource damage.
NWFPs are produced from different parts of plants or trees. Harvest sustainability can depend on the part harvested. One good example is the cycle of harvesting of bayleaf palm (Sabal morrisiana) in the Rio Bravo Conservation and Management area in Belize. Its leaves are harvested for both subsistence and market use, in the constructions of thatched roofs for work shelters, homes and resort cabanas. The harvest of bayleaf timber and palm heart kills the plant, while the harvest of leaves does not. Leaves are harvested from natural forest stands. Leaf harvesting typically occurs between the full moon up until two days before the new moon. Reportedly, leaves harvested outside this period deteriorate significantly and more rapidly than those cut in the correct phase of the moon. Ideally, all but two leaves are harvested from each individual plant. Two young leaves are left intact in order to ensure future growth (O'Hara, 1994).
The harvesting techniques, including pre-harvest and post-harvest treatment, for the various NWFPs will vary considerably for both wild and cultivated sources (see the paper by Lintu on "Trade and Marketing of NWFPs" for examples of post-harvesting operations).
In many cases, the harvest technique adopted is of fundamental importance in guaranteeing the sustainability of the resource. One example is Prunus africana (african cherry), a multiple-use tree species with economic and medicinal value (Cunninghan and Mbenkun, 1993). Bark is the major source of an extract used to treat benign prostatic hyperplasia. All bark is taken from wild P. africana populations in Afromontane forests of Cameroon, Zaire, Kenya and Madagascar. This occurs in Afromontane forest "islands" surrounded by savanna that provide habitat for important endemic birds, mammals and plants in both Madagascar and continental Africa. P. africana has a remarkable ability to withstand bark removal, however, die-back and felling of trees are frequent in high-priority conservation sites. A real effort has been made to ensure that all bark harvesters are shown the correct procedure of removing bark "quarters" from the tree trunk, starting the bark removal above ground level, not above the first branch.
The harvesting standard for many NWFPs is poor and rudimentary, and when confronted with higher and more regular commercial demand it has tended to be wasteful, destructive and unsustainable. That is the case of products such as copaíba oil, chicle gum and Brazil nuts from the Amazonia region. The collectors and extractors of these products can be unskilled and in scientific (and even in practical) methods. Some new techniques would require education rather than tools and equipment, others the reverse. For example, copaíba oil (Copaífera multijuga) should be harvested by drilling a hole with a brace and bit, which could be found cheaply at the depot where the copaiba is purchased, rather with an axe, which causes wounds that do not heal.
For many NWFP resources, the pre-harvesting preparations are of fundamental importance for the success of the entire harvesting operation. Guaranteed land and resource rights (or usufruct rights) are the first step in encouraging the sustainable harvest of NWFPs. Such rights, in fact, can allow producers to develop sustainable processing techniques. Furthermore, they allow harvesters to develop long-term harvesting strategies for single species and multiple species associations. Finally, they allow harvesters to make financial investments in the equipment and tools needed to harvest or add value by processing their products. Also, there are different systems of organising harvests of NWFPs prior to the start of actual harvesting operations. One common system is collection by local people under extractive rights and with some form of patronage and financial help from the purchasing agent. Another is by the employment of casual or contract labour by those who have obtained collection rights on lease. In the Amazon region the extractors and collectors of rubber and Brazil nut are often exploited by middlemen who control access to the market, or by those who have access to the resource. The system known as "aviamento" is common in the region. In this system, market goods needed by the extractors and collectors are supplied by middlemen or purchasing agents at inflated prices on credit, to be repaid in extracted products.
Post-harvest treatment is important to avoid product losses. For example, for some latexes like rubber, the crude exudate is collected then boiled to pasty consistency, and cooled into balls or blocks for packing and transport. However, for many NWFPs little is known about post-harvest treatments. For example, most NWFPs from the Amazon region have well-defined and relatively short harvest seasons. Markets for such products, however, could easily be sustained throughout the year if produce were available. Harvest itself is usually an arduous task. Transportation to market is difficult and often must wait until a change of season. Post-harvest treatment and proper storage of products is of fundamental importance for the success of the enterprise.
Harvesting is thus seen as the vital link between resource management of NWFPs and resource use. Therefore, when developing integrated management plans, forest managers should keep in mind the necessity to rationalize and improve harvesting systems and practices. This could involve improved tools and techniques, training and skill improvement, incentive systems institutional and legal arrangements, promotion of local processing and value addition, and linking harvest to processing.
As mentioned earlier, parks and reserves and buffer zones around these conservation areas play an important part in national and international efforts to conserve the genetic diversity of species providing NWFPs.
One significant aspect of NWFP resources is the rational use of buffer zones around conservation areas, mainly parks and reserves, where they help reconcile the needs of communities with the need to protect natural forests. In fact, NWFP resources have proven to be efficient in buffer zones in different situations. Buffer zones schemes, with their emphasis on meeting local needs, can provide ideal opportunities for the conservation of semi-cultivated NWFP resources and land uses which may not be possible in strictly protected natural parks and reserves (Bompard and Kostermanns, 1988).
In this section, examples are given of NWFPs in parks, reserves and buffer zones.
The one-million ha Maya Biosphere Reserve was established in early 1990 to protect the natural resource and traditional way of life of the local people. Much of the area is managed as a buffer zone for several totally protected zones in Peten. The Peten region of present-day Guatemala was the centre of the classical Mayan empire from the ninth to the twelfth centuries A.D. A modest local economy then developed based on the harvesting of mahogany (Swietenia sp.), cedar (Cedrela sp.) and chicle, the resin of Manilkara zapota, for the manufacture of chewing gum. Subsequently, allspice (Pimenta dioica) began to be exploited as condiment and xate, the fronds of two species of Chamaedorea palms, for use in making wreaths in the United States. At present more than 7,000 families earn a living from the extraction of chicle, allspice and xate from Peten. The forest has remained in a near-natural state and retained much of its conservation value (Sayer, 1991).
On the western border of Barisan Selatan National Park, Sumatra, Indonesia, Pesisir villagers have learned to protect trees and restore a forest ecosystem in the lands they have cleared, thus creating a true buffer zone adjacent to the national park. The Pesisir area is located in Lampung Province, Sumatra, and covers about 300,000 ha. About 150 years ago, villagers started to establish, on their own initiative, complex tree gardens, including fruit trees and other species, mainly based on the cultivation of the forest tree Shorea javanica, a dipterocarp tapped for resin. These plantations have thus been dubbed "damar gardens". The clear resin is exported to the United States and Japan for use in the paint and varnish industry. Patterns of species diversity and structural complexity in the damar gardens are similar to those of natural forest ecosystems (ITTO, 1993).
The conventional management of "opened" lands is a classic taungya-like process of tree plantation establishment. Damar gardens fulfil several functions commonly recommended for buffer zones. In supplying wood and other forest material for home consumption and in allowing the maintenance of commercial resin collection traditionally related to the forest ecosystem in the area, they relieve human pressure on the remaining natural forests. They also represent an uninhabited belt of several km wide between villages and the park, the ecological value of which should not be neglected.
Another example is rattan palm collection, cultivation and processing, which provides an important source of income for people living around conservation areas. Planting indigenous species can help to rehabilitate logged forests and justify the maintenance of forest cover. Already, rattan palm plantations are being established in the Sinharaja Biosphere Reserve, Sri Lanka, and are planned for Dumoga Bone National Park, Sulawesi, Indonesia (Sayer, 1991).
In many African countries, wildlife management in national parks and reserves has typically been based on punitive measures designed to maintain barriers between wildlife resources and local residents, drawing little or no distinction between traditional hunters and organised criminal gangs poaching on a commercial scale for big game. At the same time, the official practice of culling (or selectively slaughtering) over-large herds of protected game animals has became more and more widespread. Local people are often not sufficiently involved in the distribution of the meat and other benefits arising from culling. Other market benefits from protected areas, such as safari tourism revenues and visitors fees, are not always fairly shared with the local community whose ancestral lands were, in many cases, set aside to form the parks and reserve areas in the first place. A number of community-based projects in different parts of Africa, notably Botswana, Zambia and Zimbabwe, are inviting local participation in wildlife management and in the management of tourism facilities. One good example is the project being developed in Zambia.
Zambia has had more than a decade of experience in dealing with wildlife management and an especially serious poaching problem. Intensive law enforcement campaigns were waged in selected parts of the country, involving large amounts of money. However, despite increased arrests, wildlife losses continued; in some cases the problems even increased in areas where such programmes operated. National losses in wildlife resources during this period included near extinction of the black rhino and the reduction of over 50 percent of the elephant population. Similar trends have been documented in Tanzania, Uganda, Namibia and Kenya. Zambia's National Park and Wildlife Service undertook experimental studies and a technical workshop during 1984-1989 to identify the underlying causes of illegal hunting. As a result, a new national policy of wildlife management, called the Administrative Management Design (ADMADE), for reserved game management in reserved areas, was formulated. Based heavily on participation of people in the areas where it has been implemented, ADMADE has proved to be highly effective. In a three-year period, poaching of elephants declined by over 90 percent in one wildlife reserved area in Zambia where local participation was actively promoted. Furthermore, a resident population of black rhino suffered not a single instance of poaching during this period, despite adequate numbers to attract illegal hunters (Lewis et al., 1990).
In Zimbabwe, similar programmes have been carried out. One example is the CAMPFIRE programme (Communal Areas Management Programme for Indigenous Resources) with the objective to give full control of wildlife management to rural communities in conservation areas set aside for this purpose. The theory behind CAMPFIRE is that communities will invest in environmental conservation if they can exploit these resources on a sustainable basis for their own benefit (Murindagomo, 1992).
Research needs of NWFP resources for improving technology are tremendous, touching upon all aspects of their management and development. Some specific areas are the following:
Development of NWFPs depends on success in the marketplace. The most prominent aspects related to trade and marketing of NWFPs are analyzed in the paper by Lintu.
Institutional support is also lacking for development of NWFPs. In fact, one of the major ills affecting the NWFP sector is the institutional neglect relating to policy, strategy and plans, legal rights and arrangements, incentives, development of skills, health and safety considerations, access to information, controls and regulation related to production and marketing authorizations, and streamlined support from public administration. These questions are analyzed and discussed in the theme paper on institutional aspects by Sène.
Conservation of Genetic Resources and Biological Diversity
To ensure a sustainable NWFP supply, attention must be given not only to the regeneration, silviculture and management of the resource, but also to the conservation of biological diversity in ecosystems supporting them and to the conservation of their genetic resources.
The concepts of conserving biological diversity on the one hand, and genetic resources on the other, need to focus attention and action at different levels, i.e. on the level of the ecosystem and its component species in the former, and on within-species variation in the latter. In any genetic conservation programme it is fundamentally important to clearly specify objectives of conservation, as it is possible to conserve an ecosystem and still lose specific species. It is also possible to conserve a species and lose genetically distinct populations, or genes which may be of value in adaptation and future improvement of the species. Conversely, the loss of an individual species, of distinct populations, or of individuals of genes, may pose a threat to the continued existence of species. At the same time it is important to recognize that co-existing organisms interact, and that different levels of organisation are to a certain degree inter-dependent. A number of publications at various levels of sophistication are available on this subject and its practical implications (see for example FAO, 1989a, and references given in that text).
In situ and ex situ are important conservation methods. The first one is aiming to conserve plant and animal resources in their natural habitat while the second type (including gene banks, botanical gardens, conservation stands, etc.) are essential for plant breeding and protecting populations in danger of physical destruction. In other cases, however, in situ conservation has a number of advantages: it is especially adapted to species that cannot be established or regenerated outside their natural habitats. For example, the reproduction of many plant species depends on the presence of a particular insect, bird or animal for pollination. In situ conservation also allows natural evolution to continue and ensures protection of associated species of no present economic value (FAO, 1993d). This aspect is particularly important for NWFP plant species in tropical forests, because many of these species have not yet been studied for their economic and scientific values.
The following are some examples of actions initiated by international organisations and national governments aimed at conserving the genetic resources and biological diversity of NWFP species.
Joint investigations piloted by the International Board for Plant Genetic Resources (IBPGR) and the International Union for Conservation of Nature (IUCN) in Kutai National Park, Kalimantan, Indonesia, have confirmed that the area is an important centre of genetic variation for several important tropical fruit trees, including mango, breadfruit and durian. Of the 16 species of mango in East Kalimantan Province, 13 are edible. Most of these edible species have been brought under semi-cultivation and these, together with their wild relatives, represent a unique gene-pool which is closely linked to traditional lifestyles in the area, particularly those of the local Dayak people, whose knowledge of the diversity and growing requirements of the mango stock is unsurpassed (FAO, 1993c).
A scheme is now under way to conserve the genetic resource and to guard the local knowledge of Dayak people from loss, as part of plans to manage a buffer zone around the park perimeter.
Pinus merkusii is an important oleo-resin pine which occurs naturally in Myanmar, Thailand, Kampuchea, Laos, Viet Nam, the Philippines, and Indonesia. In the last few decades, population pressure has been causing the depletion of P. merkusii populations. Due to the importance of this genetic resource, the government of Thailand has established a conservation area of 100 ha in Nong Khu, Surin Province, for in situ conservation of P. merkusii. A second conservation area, of 640 ha located in Kong Chiam, Ubon Province, has also been created by the government. The communities living near the conservation areas have been called to collaborate and participate in conservation activities (FAO, 1989a). The action taken for in situ conservation in Thailand needs to be complemented by covering other parts of the range, in other countries, as well.
The National Biodiversity Institute of Costa Rica (INBio) entered into an innovative agreement with the multinational pharmaceutical company, Merck & Co., to enable Costa Rica to obtain the funds and experience necessary to conserve its biological diversity. INBio's work is based on the premise that the only way to save tropical biological diversity is to learn more about it and to use it sustainably, for intellectual or economic purposes. One of the cornerstones of INBio's programme lies in Costa Rica's System of Conservation Areas, a network of parks and protected areas that comprise nearly a quarter of the nation's territory. It is felt that most of the estimated 500,000 species of plants, animals and micro-organisms thought to exist in Costa Rica are being protected through this network. As part of the agreement, ten percent of the payment received by INBio goes directly into Costa Rica's conservation programme (i.e. conservation of the extraordinary and endangered biological diversity of the Isla del Coco National Park). Also, a national biological diversity inventory of fauna and flora, including NWFP resources, is being conducted (Sittenfeld and Gamez, 1993).
Actions are being taken by different international organisations and national governments (e.g. by FAO in Brazil, Indonesia, Malaysia, Peru and Rwanda) aimed at monitoring genetic resources of heart-of-palm (Bactris spp.), NWFPs medicinal plants, and research related to in situ conservation of ecosystems and species of the Atlantic forests of Brazil and rattan palm genetic resources in Malaysia. Networks between institutes in the arid and semi-arid zones were promoted for genetic resources work in Acacia and Prosopis species, and for neem (Azadirachta indica).
Like any other land use, the gathering and utilization of NWFPs can give rise to conflict. There may be competition among interested industries or groups of consumers for the utilization of the same NWFP raw material, causing demand conflicts. Conflicts are likely to arise in situations where rights are separately assigned to wood and NWFP resources. There may be competition with foresters who wish to harvest timber or between conservation and utilization interests for the plant and wildlife resources. The absence of well-defined boundaries of government-decreed reserve, community forest land, and private concessions also invites land disputes and conflicts in the gathering and utilization of NWFP resources. At the community level, conflicts may also arise between indigenous and migrant users or between groups seeking to use the resource in different ways.
These conflicts are important because the long-term sustainability of the forest resources and their residents depends upon the development of successful strategies to harmonise these interests so that the economic needs of people can be met while maintaining biodiversity. These conflicts in resource use have to be considered because they can be the major causes of resource destruction.
Nair (1990) gives one example of demand conflict in Kerala, India, due to shortage of bamboo reed (Ochlandra travancorica), an important raw material for traditional cottage industries and for modern large-scale pulp and paper industries.
In order to avoid conflicts in resource use between farmers and land-owners on the one side and Amerindians, rubber tappers and NWFP harvesters on the other side, the Brazilian Government decreed the formulation of 14 extractive reserves in the Amazon region, of which four were operational in 1989 (Fearnside, 1989). Here, the land is leased for an initial minimum period of 30 years to the extractivists/rubber tappers and ownership is retained by the Government, promoting change from aviamento to autonomous system of management in more accessible areas. Security and autonomy, and consistent and equitable income from harvesting of NWFP resources give the people involved an incentive to conserve and sustainably manage the forest. This was also the strong rationale for the Guatemalan National Congress to pass the Maya Biosphere Reserve Law in 1990. About one half of the reserve (750,000 ha) is designated as an extractive reserve for xate, allspice, chicle and other important products.
In Nigeria, in order to avoid conflicts related to the conversion of areas with highest potential for sustainable forest and wildlife management to other land uses, the Government in May 1990 decided to give village communities usufruct and management rights over local forest as long as management plans were drawn up and agreed upon (ARD, 1991).
In general, the obstacles to using and developing NWFPs are not greatly different in degree from the problems that have confronted other land uses or commodity sectors in the past.
A most serious obstacle to better use of NWFP resources is neglect by policy-makers, planners and forest managers. In most forest policies, NWFPs receive only passing mention, without clear objectives, targets, or strategies for development. NWFPs are not treated at all in official statistics and surveys. Other serious land-use issues relegate NWFP development to low priority. The same attitude persists also in most international agencies. Some planners are prejudiced against what they see as the retrograde or archaic "back-to-nature" aspect of NWFPs. On the trade side, major exporters of these products are often cautious about releasing data about quantities and revenue, which they regard as trade secrets.
Several factors constraining the sustainable development of NWFP resources are purely of forest origin. These include: lack of inventory/assessment, including its planning, which often lacks a scientific basis, and effective conservation measures; lack of management systems applied to NWFP resources; lack of appropriate cultivation practices mainly in the tropics and lack of harvesting techniques including pre-harvest and post-harvest treatments. The competing demands on forests which change the land use in particular and large-scale timber production are potential threats to NWFP resource sustainability. Poor harvest results in resource damages, as discussed above. Little knowledge exists about: the inter-relationship between the majority of NWFP species and their surrounding environment; the extent of their variation in nature, productivity, quality standards of products, characteristics and uses; processing and storage technologies; profitability; development potential and management regimes for sustainability of the resources including regeneration techniques. Information on production and domestic consumption is strikingly lacking for most NWFPs. This makes it still harder to integrate their use into development schemes at their outset. Also, extensive gathering and inappropriate management regulation have often caused NWFP resource depletion. Gathering or extraction of natural resources can only support low human population densities, and increasing population pressure have negatively affected the sustainability of the resource.
Recently countries have taken action to address some of these constraints. In Brazil, the government is negotiating a loan with the World Bank for strengthening conservation measures related to the national conservation programme (national parks, conservation areas, reserves, etc.), including demarcation of boundaries of these conservation areas, land tenure rights within conservation areas, research and strengthening of institutions (e.g. of the government agencies responsible for administering parks, conservations areas, reserves, etc.). The project on Conservation for Sustainable Development in Central America (OLAFO), conducted by researchers of the Tropical Agricultural Training and Research Centre (CATIE) in Guatemala, Costa Rica and Panama, is an example of efforts to develop appropriate management systems for NWFP resources.
Serious constraints affecting NWFP resource sustainability and development stem from the fact that the right to these resources and their benefits is rarely specified in detail in forestry concessions, permits or land deeds. As a matter of fact, in most cases, NWFP resources are not mentioned at all. In many countries, government legislation allow collection of NWFPs by an extractive community or user groups only for subsistence, but not for commercial purpose. Clear and legal land tenure and resource rights for forest residents are essential first steps towards creating an economy based upon the sustainable development and use of the forest and a wide diversity of NWFPs, and for conserving biological diversity. The extractive reserves established by the Brazilian government in the Amazon region is an example.
As outlined above, most conventional methods developed by foresters are primarily for timber productions, with emphasis on cutting cycles and silvicultural techniques to increase merchantable volumes of timber. Even plant ecologists working in the tropics have only rarely addressed the problem of managing NWFP resources.
As discussed above, controlled harvesting and periodic regeneration surveys alone can frequently provide a simple and effective method of achieving a sustainable harvest of forest resources. In this method, the intensity of human intervention is adjusted to account for the ecological dynamics of the target plant species population, not the other way around. The conventional methods of forest management however, require a more intensive form of resource intervention through silvicultural techniques or treatments.
A strong and continued political commitment at the highest national governmental level is indispensable for sustainable forest management. National land-use policy should aim at sustainable use of all natural resources, including the establishment of a permanent forest base. As part of that, an agreed forest policy should be supported by appropriate legislation (ITTO, 1992).
The procedures suggested in this section for managing NWFPs on a sustained-yield basis can be applied to almost any class of NWFP resources (i.e. reproductive propagules, plant exudates or vegetative tissues). Furthermore, their application permits great flexibility, so that operations can be tailored to suit the ecological requirements of a particular site or plant population.
Proper planning is an essential component of long-term sustainable forest management, and at the operational level reduces economic and environmental costs.
Important points to be considered in the first step of planning non-wood resources management are the needs for adequate forest ownership, institutional, labour and capital arrangements. Resource access and right for benefits should be specified in detail, regardless of whether the management area is a national forest or a privately owned or customarily held forest. Clear and legal land tenure and resources rights (i.e. for forest residents) are essential first steps towards creating an economy based on sustainable forest development. Institutional arrangements regarding who is responsible for the enterprise, including all management activities, should be considered (i.e. is it a private company, or a government agency, or is it a joint-venture between government and private company). Broad-based and organised participation encompassing local groups, women, and indigenous communities is an essential means of strengthening the institutional structure for planning management activities and for the success of the enterprise. Adequate investment and efficient institutions, including credit facilities on easy terms, extension support, and effective incentives linked to key objectives and target groups, are of fundamental importance. Also important is the availability of multidisciplinary trained human resources for planning, field work and analysis and interpretation of data on management.
The next step in planning is to select, define and delineate the precise boundaries of the management area within which the activities are to occur. Without this information, it is not possible to do detailed forest mapping, conduct suitable inventory, define forest management units or estimate the total harvestable resources.
Supporting information about the forest management area should be collected. Information should include soil or geologic survey maps, large-scale topographic base maps, standard aerial photographs, satellite images, climatological data, descriptive analysis of vegetation, inventory data forest maps, etc. A literature review should be conducted on the forest area, including possible information from herbaria about plant species in the area.
A management inventory supported by a detailed map is indispensable in preparing working plans for each forest management unit.
An assessment of NWFP resources by appropriate categories and a detailed prospecting for specific products (e.g. gums, resin, fruits, phytochemicals etc.) in the area is an essential part of the management process. This will help to identify candidate species or groups of species and distribution of suitable areas to be developed for specific products. This will also serve as a sound basis for planning the management activities. To achieve this objective, detailed forest inventory and mapping should be carried out.
As outlined earlier, forest inventories involve extensive work and the counting and measuring of plant species. Quantitative information should also be gathered on timber species, both commercial and non-commercial species. During this inventory, other aspects of the forest, such as its importance for wildlife populations, can be qualitatively assessed. Different aspects related to forest inventory for NWFP resources have been discussed above. From the earlier discussion, it is suggested to use a systematic sample of fixed-width transects, with lower diameter limit of 10 cm DBH (except for certain palms, lianas and shrubs) and sample intensities not below 3 to 5 percent of the total management area.
The inventory will provide information related to the overall ecological potential of the NWFP plant resources to be managed (i.e. reproductive biology, regeneration and growth strategies, life cycle, abundance of occurrence in different forest types, population structure and size class distribution, end-uses types of products produced, etc.). Also, the inventory data and additional baseline field information related to different forest types occurring within the management area are important for determining the actual pattern and intensity of forest exploitation. At the same time, attempts should also be made to identify and delineate the different forest types and plant communities using photogrammetric analysis of aerial photographs or photo interpretation. These features should then be mapped and the total area under each forest type can be estimated planimetrically using this map based on the floristic composition of different forest types or plant communities. These forest types contain different NWFP resources that must be managed in different ways.
The inventory, together with economic and social criteria, provide data needed for selecting the NWFP resources to be managed. As discussed in previous sections, aspects related to botanical characteristics provided by the inventory and additional baseline field information can determine the management potential of NWFP resources.
The subdivision of the management area into distinct management units should be based on estimates of total population and their productivity, carried out through a yield study, for different sites. The basic objective of the measurement of productivity is to estimate the quantity of the desired product to be produced by the NWFP resources within a particular habitat. The measurement of productivity has been discussed earlier; Peters (1992) describes criteria for subdividing the area into management units.
The selection of these units should be based on a posteriori statistical comparison of the density and yield data, both between habitats (for a single species) and between species within a single habitat. Regression analysis and simple analysis of variance can accomplish this task.
The plant species or combination of plant species providing NWFPs that are most productive in a particular forest type or habitat are then identified. Those areas containing the most productive populations of the desired species selected for management should be located and outlined on the forest type map of the area. This procedure will generate a second forest type map (defined by the productivity of specific plant species yielding NWFPs). The finished map is an important document that will serve as the basis for all subsequent management planning in the area.
The determination and mapping of management/production units is a routine part of management operations on large timber estates. This procedure, however, is not reported in the literature relating to the management of NWFP resources. The practices that most closely conform to this logic are the delineation of different "estradas" by the rubber tappers in Brazil, as observed by the author in the Amazon region of Brazil, or the qualitative division of forests by the Daret of Balai, West Kalimantan (see above). Both of these groups use resource abundance and productivity as a criteria for subdividing the forests.
As discussed in an earlier section, efficiency and sustainability of forest management depend to a large extent on the quality of harvesting operations. Pre- and post-harvest prescriptions are important to: minimize logging damage; attune harvesting with the silvicultural concepts adopted; assess logging damage, the state of forest regeneration, the need for release and other silvicultural operations to assure the future of the NWFP crop.
The inventory and yield studies are used to estimate the total harvestable yield from the forest. The next step is to estimate a sustainable harvest yield or harvest level. As outlined previously, from a management perspective, a truly sustainable system for exploiting NWFP resources is one in which fruits, nuts, latexes, gums, and other non-wood forest plant products can be harvested indefinitely from a limited area of forest with negligible impact on the structure and functions of the plant populations. By collecting and analyzing data on the growth, mortality and reproduction of different individuals within the population, certain predictions can be made about the impact of harvesting before the resources are actually extracted from the forest. The importance of this technique is that over-exploitation can be identified first in a computer simulation, not 20 to 50 years later in the field when it may be too late to remedy. Two procedures can be used to estimate a sustainable harvest level or intensity:
Two different management strategies are available to achieve the control of the intensity of NWFP resource extraction. Harvests can be controlled by regulating: (1) the number or size of the trees exploited or (2) the total area from which the NWFPs are extracted (see Peters, 1992, for details about these two methods).
The forest management area should be protected from activities that are incompatible with sustainable production of NWFPs, such as encroachment by shifting cultivators often associated with the opening up of the forest. Fire is also a serious threat to future productivity and environmental quality of the forest. Access to logging roads that are not part of the national infrastructure (i.e. through-roads) should be strictly controlled. A fire management plan should be established for each forest management unit, taking into account the degree of risks (ITTO, 1992).
The above recommendations have shown that the combination of inventories, yield studies and monitoring can provide the resource manager with the essential ingredients required for developing management programmes. This is information about: (1) the density and distribution of resources within the forest, (2) population structure and productivity of NWFP resources to be managed, and (3) the ecological or demographic impact of resource harvest.
In many cases, simply defining an effective compromise between harvest intensity and population recruitment is sufficient to ensure the long-term sustainability of resource extraction. Some species, however, may not be so easy to exploit. They may occur at low densities in the forest, exhibit marginal productivity, or be extremely sensitive to the effects of harvesting. For these reasons, in addition to controlled harvesting the sustainable management of these species will require some form of direct silvicultural manipulation. As discussed earlier, controlled interventions through silvicultural treatments can stimulate the abundance, productivity and regeneration of plant species that yield NWFPs.
Readers are referred to the scientific literature (e.g. ITTO, 1992a, 1992b, 1993; FAO, 1989b, 1989c, 1991a) for suggestion and guidelines for sustainable managements of natural tropical forests. The recommendations in this paper should be complemented, wherever appropriate, with the suggestions and guidelines contained in that literature.
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