When considering possible action and investment in the conservation of ecosystems, species and genetic resources some assessment of the future demands on the forest, and the land it presently occupies, is essential. The existing growing stock and particularly the advance growth at the time of harvesting will determine the species composition and possible selection of the seed bearers at the end of the cutting cycle, perhaps 15 to 30 years, or up to 45 years or more ahead in some cases. However the management and conservation of the genetic resources of the timber crop are concerned with the influence on the next reproductive phase and on subsequent generations, taking into account such factors as the possible effects of inbreeding, genetic pollution of locally adapted genepools by outside (introduced) pollen sources, or genetic drift on the evolution of the populations. This implies consideration of the management and production objectives that may apply perhaps 150 or more years in the future.
Any attempt to predict the socio-economic and environmental situation of the production forests so far ahead must be so uncertain as to be of very questionable value. Even within the past half century the changed nature of the demands and opportunities surrounding the forests has radically altered approaches to management. Moreover the rapidity and scale of the changes, particularly in aspects of technology relating to the use of timber and wood and to the possibilities for manipulating the crop, including aspects of genetic engineering, are still apparently increasing. In addition the probability of significant change in global and regional climates adds further uncertainty, since the exact nature of such changes and therefore the nature and extent of their impacts on the forests, and on the environments for future production forests, are largely unpredictable. It is thus not to the prevailing socio-economic, market and environmental conditions, nor those of the past decades, that the genetic resources of the forest must be matched, but to those well into the next century. Failure to keep this fact in mind could lead to a dangerous limitation of the conservation objectives and of the necessary genetic base to adapt to unforeseen demands.
Despite concern for great uncertainty related to future environmental conditions and market demands described above, the inevitability of the increase in human populations and in the severity of the related impacts on natural resources, including natural forests, must be the central concern in forward planning. Unless some significant additional improvements beyond current expectations can be made in agricultural productivity on the existing crop lands, very large areas of additional arable land will be needed each year to feed the increasing population. On past and present experience this land will be taken largely from existing forests. Economic analysis of the productivity and contribution to national and local needs from the natural forests, in the face of the increasing demands on land, is likely to conclude that the natural forest is unacceptably expensive in its use of land. At the same time shortage of capital in most tropical countries, and the high discount rates applied to project appraisal in the use of external funds, are a strong deterrent to investment in the rehabilitation of the extensive areas of already deforested and degraded lands. The effect on the forest “land bank” is therefore likely to be as devastating in the near future as in the recent past, and as the forests are further reduced the impact on their genetic resources is made more severe. Again on past experience this is likely to be the situation even if, as is increasingly the case, agricultural production on the deforested land becomes unsustainable due to the inherent intractability and low fertility of most areas still under forest. The eventual costs of attempting to restore productivity to the deforested lands are likely to be very high, and the success may well depend on the availability of the genetic resources of some of the original perennial vegetation, shrubs and trees.
On the assessment of some agricultural crop geneticists we have already come very near to the limits of lands utilizable for agriculture (Hawkes 1990) and must look to the more effective use of marginal lands through adaptation based on selection and breeding, for the needed increase in food production. This underlines the importance of the genetic resources of woody multi-purpose species in dry and semi-arid lands, which becomes even more significant in the context of global warming and with the likelihood of more extreme climatic events and stresses. In this respect the conservation of critically important and endangered fragments of dry forest, and of their genetic resources such as i.a. those in the Pacific lowlands of Central America, is dependent on the recognition of their importance for long-term sustainability of land use. Similar considerations apply to many remaining areas of tropical forests and rainforests on sites of low inherent fertility, such as the deep sands underlying some Amazonian rain forests and the podzols of heath forest formations.
While trends in population and land use are clear, predictions of future levels and patterns of timber and wood consumption, even a matter of a few decades ahead, are more problematical. The long-term predictions required in the context of genetic resource conservation must be extremely uncertain. Most forecasts of timber trends have a shorter horizon but a recent study by Arnold (1991) undertaken for the U.K. Forestry Commission, provided some valuable indications of longer term trends.
In global terms, and also for each of the major industrialised regions, the rate of growth in industrial wood consumption has been slowing down - worldwide from 3.5% annually during 1950/60 to 2.2% in 1960/70 and 1.1% in 1970/80 (Sedjo and Lyon 1990 in Arnold 1991). This apparently reflects a number of long term trends which seem likely to continue, namely that the uses and markets for some applications, such as housing in much of Europe, North America and Japan, seem to be approaching maturity, while improvements extending the life of wood products, reductions in wasteful uses of wood, and increases in the role of substitutes for timber, are having an increasing influence on levels of demand. The results of the analysis reported by Arnold (1991) show that consumption is rising faster in the developing countries than in the industrialised regions and that substantial increases in the demand for industrial wood are expected in Africa, Asia and Latin America in the remainder of this century.
The forest-based sector in developing countries experienced rapid industrialisation between 1950 and 1980 but increasing domestic demand, linked to the expanding populations, absorbed the major part of the increase in output (ECE/FAO 1986). Since the domestic markets in tropical timber-producing countries are less demanding in terms of quality than their export markets they are able to utilise a wider range of species and, as the total wood resources from dwindling areas of natural forest diminish, they may accept low-grade material of mixed origin, rather than the high quality and consistent supplies required by the international markets. At the same time the pressures on land have led several tropical countries, especially those with high population pressures, to propose the effective replacement of natural forest by industrial plantations to meet timber production needs (Nwoboshi 1987; Kio and Ekwebelan 1987).
The implications of these trends for the management of natural tropical forests are for the acceptance by the domestic market of mixed, general-purpose timber, to be provided at minimum cost with little regard to the selection of species, and perhaps accompanied by the progressive reliance on artificial regeneration of fast-growing species, including exotics, rather than natural regeneration of the native forest. Unless active moves are made to counteract it, the management of natural forest is likely to tend towards the “log and leave” approach (Poore 1989) with limited reinvestment in control either of logging or of subsequent protection of the regenerating forest. This pattern of operation is already followed in many tropical forests, reflecting the low-input and low-output levels of funding and revenue. Investment may be more readily attracted to industrial plantations and so far as these also will be intended primarily to meet domestic needs for wood and timber, the species selected will be fast-growing general-purpose ones, capable of satisfactory growth on the degraded land not required for food production. Pioneer species, such as the tropical pines, are the natural choice for such plantations, with the advantage of having already been the subject of substantial research into their genetic variation and adaptation to a range of sites, through provenance trials (Barnes and Gibson 1984; Gibson et al 1989). If this trend were followed to its' logical conclusion the conservation of the genetic resources of tropical timber species carried out in production forests, would be limited to the pioneer and fast-growing gap-phase species capable of maintaining viable populations through repeated cycles of largely indiscriminate fellings, at intervals of probably 15 to 20 years on many sites.
The international trade in tropical timber has been an important source of revenue for many tropical countries, based in the past largely on the first cut in natural forest, including a high proportion of high-quality hardwoods with exceptional or even unique qualities. A majority of the highest value timbers are among the slower-growing late-phase ecological groups, characteristic of the mature-phase and climax forest. Some important commercial hardwoods, particularly among the Meliaceae (e.g. Cedrela odorata, Entandrophragma spp, Swietenia spp, Terminalia ivorensis, T. superba, Milicia excelsa [syn. Chlorophora excelsa] etc) are natural gap-phase species but are unlikely to form a large proportion of the crop under short-cycle “log and leave” systems of management. Without availability of continuing supplies of substantial volumes of such medium-value hardwood species in future timber harvests the prospects for profitable export-oriented management of tropical forests seem poor.
The bulk of the world's current supply of industrial wood comes from the forests of the north temperate zone where in total, in contrast to the tropical forests, the net increment exceeds the removals and the volume of the growing stock is increasing. Moreover the developing trend in this zone to remove productive land from agricultural production in response to economic and market related pressures, is expanding the potential for further increases in both area and productivity of the forests. While there may be some constraints on industrial wood production from these temperate forests if decisions are made to restrict timber harvesting in favour of amenity and recreational objectives, and due to hazards as a result of possible pests, diseases or air pollution, the likely effects of global climate change seem favourable for increased growth rates in forests in the north temperate zone. Moreover the strong concentration of scientific expertise, and the high level of forest management generally in this zone, offer the best basis to anticipate the effects of climate change, to mitigate the adverse impacts and to take advantage of the new opportunities for faster growth. It seems likely, therefore, that the future trade in tropical timber will be increasingly restricted to the export of higher quality woods to the industrialised world, with some continuing and developing trade in general purpose timber between developing countries (Arnold 1991).
Leslie (1987) has drawn attention to the special economic importance of the high value timbers which are unique to the natural tropical forests, and for which, therefore, there are no adequate substitutes. He points out that the market outlook for these timbers is the direct opposite of the weak market prospects for most of the products of the alternative agricultural or plantation management systems which compete for land with the natural forests. In these circumstances the relative economic prospects for natural forest management, if based on such high-value timber species, can only improve.
Some recent studies of the possible incentives to sustainable tropical forest management highlight the potential importance of securing or transferring a greater proportion of the ultimate value of the products, as realised in the market outlets in the industrialised countries, for reinvestment in the forests (e.g. OFI 1991). An important aspect of this is the development of efficient secondary and further processing of forest products in the countries of origin. Exports of processed products have been expanding, despite some evident constraints on market opportunities in the main user regions. There are dangers in the expansion of industrial capacity beyond the properly sustainable levels of the allowable cut in the forests. Nevertheless with adequate quality control and marketing arrangements high-value secondary and further processing seems the best option to maintain a unique market niche for selected tropical timbers, thus providing an incentive for sustainable management of natural tropical forests. Reports of species such as ebony, teak and rosewood being exceptionally traded at prices between US$ 5 000 and $ 7 000 per m3 (ITTO 1991) indicate the existence of a high value market niche which is likely to remain firm as the availability and supply of such high quality timbers from the natural forests continues to decline.
Concern among the public and the media in the industrialised countries over deforestation and degradation of the tropical forests, and particularly the impact of logging on tropical rainforests, is likely to have an increasing impact on international trade. On current trends it seems likely to reduce substantially the traditionally strong demand for tropical timber in Germany, the Netherlands, the U.K. and the U.S.A., and even in Japan. The International Tropical Timber Organisation (ITTO), at its 8th Council Session in 1990, adopted the target date of the year 2000 by which to ensure that all tropical timber in international trade should come from sustainably managed forests. At the same session it approved a set of international guidelines for the sustainable management of natural tropical forests (ITTO 1990) elaborated by an Expert Group in which individual experts, international organizations (FAO) and an NGO (WWF) were represented. At its 10th Session in 1991 the ITTO Council initiated action to develop Guidelines for the Conservation of Biological Diversity in Production Forests, to complement the already existing, general guidelines on sustainable management in natural and plantation forests.
To the extent that the timber producing countries were able to achieve the ITTO target of ensuring sustainable management of the production forests by the year 2000, and installing internationally accepted certification for timber to that effect, the related consumer resistance to tropical timber imports might be removed. The criteria for sustainable management seem certain to include aspects of ecological and environmental concern, including the conservation of biological diversity and of genetic resources of the tree species being marketed. Depending on the criteria adopted for judging sustainable management, production forests managed to maintain a broad spectrum of species and their intra-specific variation, and including a range of successional stages over the national territory, are more likely to qualify for public and political approval than more intensively logged on a short cutting cycle, without concern for genetic conservation.
Countries which are seen to incorporate the conservation of forest genetic resources, and concern for the broader range of biological diversity, within their management systems in production forests will be best placed to secure favourable markets for timber.
The link between tropical forests and the stability of local, and possibly regional and global climatic conditions is widely accepted, if still imperfectly understood. Studies in the Amazon and in West Africa have shown the importance of transpiration from tropical forests in influencing local rainfall, and their significance in the hydrological cycle (Salati 1987; Shuttleworth 1988). It is thought that tropical forests may play a key role in the general circulatory systems of the atmosphere, with related influence on precipitation patterns. Their role as a major store of carbon is clear, although the mature-phase forests are presumed to be in approximate equilibrium in their sequestration and discharge of carbon dioxide. In that respect the establishment of fast-growing young forests is clearly a potentially greater influence on possible global warming, to the extent that it may be the result of increasing carbon dioxide concentration in the atmosphere.
The species composition of tropical forests, except insofar as it may be essential to the functioning of the ecosystem on a given site, is unlikely to be of critical importance to their role in regional or global climatic stability. There is also little evidence for links between species diversity and ecosystem function (di Castri and Younes 1990). With the exception of certain “keystone” species there is apparently a high level of species redundancy in the functioning of the highly diverse tropical forests, and it seems likely that well-managed secondary forests, composed largely of relatively fast-growing species characteristic of the earlier stages of ecological succession, could adequately fulfil the forest's environmental role.
However it is also increasingly accepted that the loss of biological diversity is itself an environmental problem. The danger for such loss is immediate, and therefore as urgently in need of increased international action as is the threat of global climate change.
In 1988 UNEP, together with other members of the Ecosystem Conservation Group (then consisting of FAO, Unesco, UNEP, IUCN, and WWF International) initiated action towards the preparation of an International Convention on Biological Diversity. From the outset the special importance of tropical forests in this connection was recognised. The fundamental requirement of the in situ conservation of genetic resources and the conservation of ecosystems and natural habitats was taken as a central principle, linked to general obligations on all parties to a possible Convention to conserve natural habitats, species, viable populations and genetic resources in situ. There was also widespread recognition of the need to integrate the conservation of biological diversity with development, and the possible role of forests managed for the production of timber and other products in this connection. The various drafts of a convention prepared by the Ecosystem Conservation Group, were subsequently discussed by national Governments in the context of preparations for the United Nations conference on Environment and Development (UNCED)1. WRI, IUCN and UNEP, in consultation with FAO and Unesco, also prepared a “Biodiversity Strategy and Action Plan”, calling for a decade of action, and for the necessary financial resources to be made available internationally (WRI 1992).
Discussions of a possible international “umbrella” convention, charter, protocol or other agreement aimed at the conservation of forests, as suggested by the group of seven leading industrialised countries at their meeting in Houston in July 1990 were actively pursued in the FAO Committee on Forestry in September 1990, and at the FAO Governing Council meeting in November 1990. Subsequently it was agreed to pursue these discussions in the forum of the preparatory committees for the UNCED meeting, and this led to the formulation of a draft statement of principles for the management, conservation and sustainable development of all types of forests2. Although not legally binding the “Forest Principles” may be used as a basis for a more formal international agreement in future. Any such international instrument should pay particular attention to the importance of tropical forests in the conservation of biological diversity and genetic resources, and to the implications for the provision of both financial and technical assistance to the tropical countries in that connection.
1 The resulting International Framework Convention on Biodiversity was signed at the UNCED Conference in Rio de Janeiro (June 1992) by 154 countries; it will come into force after national, governmental ratification by 30 signatory countries (see e.g. FAO 1992b).
2 “A Non-Legally Binding Authoritative Statement of Principles for a Global Consensus on the Management, Conservation and Sustainable Development of all Types of Forests”, was adopted at UNCED, Rio de Janeiro (June 1992).
While genetic diversity of the tropical forests may not be significant in the forest's climatic function, it is certainly vulnerable to the effects of climate change. The effects may be particularly severe in the major ecotones, where adjacent biomes meet, for example in the transition zone between closed tropical forest and savanna woodland (Holdgate et al 1989). In such situations, where it has been suggested that a change of 3°C in average temperature would lead to a shift in habitat type of roughly 250 km in latitude (MacArthur 1972, in McNeely 1990), each species will respond within its own capacity. This will be strongly influenced by the levels of genetic diversity between populations and between individual trees within each species, and places greater significance on the conservation of the genetic resources of the woody species in such transition zones.
In the tropical forests pioneer species with light, wind-distributed seed, or those with highly effective dispersal through birds, bats or other animals known to disperse seeds over wide areas, are likely to be able to adapt more easily to climatic change than species with large, heavy fruits that fall intact, and whose seedlings are adapted to survive under the forest canopy. This suggests that the trees characteristic of mature-phase climax forest are likely to be more disadvantaged by climate change than the more widespread pioneer species, especially if the latter also exhibit a high degree of diversity and strongly outbreeding systems.
Increased recognition of the importance of biological diversity, and the exceptional wealth of tropical forests in this respect, may improve the opportunities for systematic inclusion of aspects of in situ conservation of genetic resources in fully Protected Areas, such as National Parks or Native Reserves. The principles were already established in the World Conservation Strategy (IUCN 1980) which has been widely accepted. Central to the Strategy is the recognition of the interdependence of conservation and development. This theme is further developed in the 1990 adaptation of the Strategy (IUCN 1991a) which calls for a comprehensive system of protected natural forests and for expansion of efforts to conserve forest genetic resources. The use of the term “Protected Area” covers a variety of approaches to the protection and management of natural and semi-natural areas, classified into eight major categories. Several of these categories can permit sustainable harvesting of forest products within the management objectives and practices, both to conserve biological diversity and to provide sustainable benefits to local people and to national economies. This applies for example, to Category IV (Nature Conservation, Managed Nature Reserves or Wildlife Sanctuaries), Category VI (Resource Reserves), Category VII (Natural Biotic Areas or Anthropological Reserves, for Traditional Local Harvesting of NTFP) and Category VIII (Multiple-Use Management Areas or Managed Resource Areas) (IUCN 1990). However the fundamental objectives of the Protected Areas are to maintain the ecological processes inherent in the natural systems and to conserve their genetic diversity and resources for sustainable use.
Two other categories of conservation sites are recognised internationally which may overlay the IUCN categories, namely the Biosphere Reserves, under the Unesco Man and the Biosphere (MAB) Programme; and the World Heritage Sites, nominated by countries party to Unesco's World Heritage Convention. The Unesco MAB Programme works closely with FAO, UNEP and IUCN and with the International Council of Scientific Unions (ICSU). All Biosphere Reserves are intended to have a scientific as well as a developmental objective, and may permit harvesting, including logging, where considered appropriate to improve understanding of the scientific basis for sustainable management. Areas accepted as World Heritage Sites may qualify for some financial assistance through the World Heritage Trust Fund, which might entail restrictions on use of the resources. Roche and Dourojeanni (1984) have evaluated the various categories of Protected Areas in terms of their contribution to forest genetic resource conservation.
Although Protected Area systems form a central “core” in national and international action to conserve biological diversity, the developments in conservation biology (e.g. Harris 1984; Soulé 1986; Wilcox 1990) have revealed the limitations of such systems in the conservation of ecosystems, species and genetic resources. Most conservation biologists now recognise that the Protected Area networks, even at the more optimistic assessments of the areas likely to be secured, will not be able to conserve all, or even most, of the species and genetic resources desirable (FAO 1989a; FAO 1992c; McNeely et al 1990). The total area and pattern of distribution needed would far exceed the practical possibilities and the willingness of local communities and governments to set aside such areas from productive use, or to decisively limit such use. The only solution, therefore, is a planned mosaic of Protected Areas, integrated with production forests managed in such a way as to contribute in a complementary capacity to the overall conservation of biological diversity in general, including genetic resources of important component species.
The location of Protected Areas is normally based on considerations of natural landscape value, species richness, endemism, degree of threat from destruction of the habitat, theories of Pleistocene refugia and attention to so called “hot spots” in deciding priorities (Wilson 1988; Myers 1988; Reid and Miller 1989; McNeely et al 1990; Wilcox 1990). Their representativeness in respect of forest genetic resources is severely limited both by the lack of information on patterns of distribution, especially at the intra-specific level of variation, and by the pressures from other land-use systems. Most remaining areas of primary or climax forest are on sites judged unsuitable for intensive agriculture or very remote from centres of population, or both. In the fertile tropical lowlands, forests have either been heavily modified or eliminated. Where the opportunity to select and set aside Protected Areas still exists the attempt to conserve potentially valuable populations of important species must normally be based on patterns of environmental variation or of variation in plant communities, rather than on detailed knowledge of the genetics and actual variation patterns of their component species.
The size and shape of individual Protected Areas also are strongly influenced, and often determined, by outside pressures rather than theoretical considerations of minimum population size. However even small areas can make important contributions to conservation (Simberloff 1982, 1983) and reserves of even less than 10 ha can be effective in conserving viable populations of many plant species (McNeely et al 1990). One advantage of small areas is that they are more manageable, both for the study of their species composition and autecology and for their effective protection, and they offer greater possibilities for diversification over the whole of the natural territory. A thorough inventory of the tree flora, and desirably other flora and fauna (considering occurrence, density and distribution), is essential for efficient conservation, and may enable such small areas to be effectively used in conjunction with other in situ conservation sites, and with ex situ action (see also the Ghana case study).
The value of Protected Areas for the conservation of genetic resources is usually weakened by lack of resources and capability for their control and management. Roche and Dourojeanni (1984) have drawn attention to the necessity for effective management of Protected Areas, and the key role of the Managed Resource Areas (IUCN Category VIII) in this respect, since they permit manipulation of populations with a view to the utilization and possibly incremental development of their genetic resources. They have also suggested a review of the legislation governing other categories of Protected Areas, such as National Parks, in order to permit activities such as harvesting of seed and other reproductive materials. They point out that the totally protected area (“core”) within many National Parks is often sufficiently large to allow for zonation into different sections, under possibly different management objectives and practices. This principle, of the association of different systems of management within contiguous forest blocks, is very important to the effective integration of conservation and development objectives. It is well illustrated by the Virgin Jungle Reserves within production forests in Malaysia, and by the concept of “buffer zones” around protected forests.
Protected Areas, particularly those of less than ideal size and location, can only meet their conservation objectives if the land surrounding them is under appropriate management compatible with the objectives within the Protected Area itself. This may require the establishment of a “buffer zone”, which can both meet those objectives, and also provide appropriate benefits to the local people. Experience has shown that legal protection alone of conservation areas is insufficient to prevent encroachment or damaging incursions into the forest, particularly where human settlements are located close to the boundary (Sayer 1991). Moreover in relatively small reserves the tree species which occur naturally at very low densities will be at risk from possible inbreeding or inadequate levels of regeneration, which may be relieved if their populations are extended into surrounding areas of managed forest. Such extension of protection may help conserve a wider range of intra-specific variation.
Some attempts at buffer zone development have proved disappointing (Wells et al 1990) but others have been more successful. The benefits, in addition to the extension of the effective population size of some species and the separation of the “core” protected area from human settlements and intensive agriculture, include the development of local support for the conservation objectives as a result of beneficial involvement in use of the buffer zone, including e.g. hunting areas.
The definition of the buffer zone concept by MacKinnon (1981) was “areas peripheral to National Parks or reserves which have restrictions placed on their use to give an added layer of protection to the native reserve itself and to compensate villagers for the loss of access to strict reserve areas”. However Sayer (1991) interprets the concept more widely to incorporate a range of possible developmental activities which can deliver benefits to local people as well as extending the effect of the Protected Area, at least for some animal and plant species. These activities might in some cases include agroforestry, tree plantations or a variety of other land uses but in terms of the in situ conservation of the forest's genetic resources the most appropriate form of management is clearly modified utilization of the natural forest. The Corbett National Park in northern India is a long-established example of the way in which the maintenance of semi-natural forests of Sal (Shorea robusta) have buffered the Protected Area while providing a harvest of quality timber to the forest authorities and non-wood forest products to the local people.
The best realistic prospects of maintaining a buffer zone of natural forest with relatively little change in its species composition, and therefore maximum contribution to in situ conservation, are in the few remaining major forest blocks, such as Amazonia, the Zaire-Congo Basin and parts of Indonesia. Some possibilities still exist elsewhere in Africa, where population pressures around the forest are still not severe, to develop a buffer zone of secondary forest, with a higher concentration of pioneer species. However light, sustained-yield selective logging or harvesting of NTFP, possibly in combination, should be better able to maintain a wide range of total diversity. The important thing is for the management of both the Protected Area and the adjacent land to be planned and managed as an integrated unit. By this means the genetic resources of species of both the late succession forest and those of the earlier stages of ecological succession can be suitably catered for in separate management zones. Clear objectives and priorities must be set for each zone, from the central “core”, where conservation of over-all biological diversity may be paramount, through selectively logged forest, with due attention to the conservation of genetic resources of important timber trees, to the outer zones, where production of the wood and non-timber forest products may be the highest priority, with close involvement of local communities (see India case study).
A further important role for areas of managed forest outside the main Protected Areas is to serve as “corridors” for the movement of animal populations, particularly in the context of possible climate change. If sufficiently broad and secure they might also allow for migration of some plant and species, including tree species. However given the probable speed of change and the extensive fragmentation of tropical forests the movement of genetic resources of important tree species will be more dependent on ex situ conservation strategies.
Genetic resources are a national asset of the country and therefore dependent on clear national policies for their use and conservation. The potential contribution of each production forest, or unit of management within a forest, to the national objectives for conservation and/or sustainable productive use will vary according to location, species composition, size, shape, environmental features and many other factors. Its actual contribution should be determined by the objectives and quality of management, related to its potential conservation value. It is neither possible nor necessary to prescribe equal priority and intensity of in situ conservation in all production forests. At a minimum level sound sustainable management should include provisions for the protection of site conditions, seed trees, seedling regeneration and advance growth of desirable species in appropriate combinations according to management and silvicultural prescriptions. To the forest geneticist a range of possible production management systems may be acceptable in terms of their impact on the genetic resources, depending on the target populations. Extreme refinement of the composition of the forest to favour one or a few species in an originally poly-specific forests, if done with full understanding of the dynamics of the ecosystem and of the effect on its long-term functioning, may be an acceptable means to conserve the genetic resources of the principal species, albeit at the expense of the broader (species) diversity of the forest, which should receive due attention in other areas of the Forest Estate. Even clearfelling and replacement of the mixed forest by planting a single indigenous species, if based on broadly representative seed collections from the same site, might qualify as in situ conservation. However such approaches, would be exceptional to the general rule which would seek conservation through natural regeneration of the component species in the ecosystem, targeted for conservation.
In many cases the need to maximise production of wood and other products from limited areas of land requires the concentration of the site capability on the growth of one or a few fast-growing species or species groups, most likely to be from pioneer or gap-opportunist guilds, and possibly exotics. The forest manager might argue that this action supports the allocation of other forest areas to in situ conservation, as part of an overall strategy. However past experience with the putative development of “compensatory” plantations to safeguard natural forest has indicated the need for a stronger and more coherent overall plan to ensure that the conservation objectives are also met. As stated earlier the role of individual areas of production forest for in situ conservation must be determined in relation to patterns of distribution and variation of target species and populations, and to the contribution of the network of fully Protected Areas, National Parks etc, within an overall, national conservation strategy. In addition to using production forests to complement the Protected Area system, by filling key “gaps” in species ranges, or forest types, there can be additional value in the conservation role of production forests sited adjacent to a protected area, or forming a “corridor” to other managed or protected areas.
The wider regional and international interests in the conservation of biological diversity and genetic resources related to patterns of distribution extending through several countries, and to global recognition of the importance of the tropical forests in this regard, presents an opportunity to secure additional financial and technical support for conservation actions. While these international concerns, particularly when focused on existence values of biological diversity, are likely to extend beyond the more immediate use values of the forest genetic resources of direct interest to the host country, they may be used to reinforce national objectives in the conservation of selected forest areas and populations. However to ensure that full advantage can be taken of these expanding opportunities, in ways that serve the national interest, as well as broader global objectives, a clear and coherent national policy on the conservation of its genetic resources is essential.
As seen in the case studies on Ghana and India, for example, the actions needed to secure effective conservation must carefully consider and include the interests of local populations in and around the forest, and will also extend increasingly outside the forests into aspects of industry and trade; and outside the forestry sector as a whole, to areas of responsibility in other sectors of government. They may impinge on central policies related to the allocation of revenue and expenditure, and to both internal and external commercial and trading practices. In these cases the necessary changes to management practices in individual forest areas are dependent on central policy decisions at a high level, involving various sectors. Review and revision of existing laws and regulations may be needed. Although many of the actions, such as the review of the level of forest fees, the adoption and effective imposition of differential stumpage rates, the systems of allocation, duration, size and operation of timber concessions etc, are needed as much for the broad objectives of sustainable forest management, as for conservation objectives, the latter must also be kept clearly in view in determining overall policy. Similar considerations apply to the changes needed in forest management practices, and perhaps in laws and regulations, to incorporate NTFP and the involvement of local people in such management systems. The potential for this is seen in all three case studies presented in Part II of this document. The provision of a coherent system of incentives to sustainable management of the forests, at all levels from the local populations to other national groups in both the private and the public sector, and to international market conditions and investment policies, relating for example to trading practices, support for local processing, marketing assistance and maximising value of products to the country of origin, will be needed to secure greater attention to conservation objectives in the production forests. These incentives must be the subject of national formulation and may require international assistance (see the Ghana case study).
An urgent task is the determination of priority species, populations, areas and actions for the conservation of forest genetic resources in each country. This must take account of possible ex situ as well as in situ conservation, within a coherent national programme, in accordance with national policies. In a broader context, embracing all natural resource sectors, the formulation of National Conservation Strategies has been used as an aid to reviewing policies and redefining priorities (Poore and Sayer 1987). The breadth of subjects and issues involved in the whole field of biological diversity conservation has proved difficult to contain within a single comprehensive assessment, and the need for more specific definition of policies and practices linking development and conservation has been suggested (FAO 1985b; Prescott-Allen 1986). In the narrower context of the conservation of forest genetic resources, the multiple-use management of production and protection forests for the production of timber, NTFP for local use, environmental protection and the conservation of genetic resources provides a contribution to exemplify and help define the broader Conservation Strategy.
For all of the above reasons the formulation of a National Strategy for the Conservation of Forest Genetic Resources is essential, to make the best use of the land and other resources devoted to production, protection and conservation, and to the opportunities for regional and international cooperation. An important task under such a National Strategy for Conservation will be the prioritization of action and coordination of activities, including research, to make the best use of financial and manpower resources available both nationally and internationally. Without inclusion of research within the over-all strategy, there is a danger that the limited scientific expertise will be wasted or inefficiently used, through the choice of irrelevant subjects for research, or failure to integrate the work of different specialists needed to resolve a particular problem. This has been observed particularly in the fields of reproductive biology and genetics of tropical trees in relation to their conservation and management (see e.g. Bawa and Krugman 1991; Wadsworth 1975).
Studies of the effects of disturbance on the forest, and the response of the principal tree species of socio-economic value to such disturbance at various stages of their life cycle, are important for both management and conservation objectives. There is a need to coordinate action within a wide range of differing biological fields, using varying degrees of expertise, experience and technological sophistication. However too often ecological and autecological studies have lacked direct relevance to forest management activities, e.g. caused by failure to examine the comparative situations in both logged and unlogged forest.
A National Strategy for Conservation could assist in channelling research activities to the areas of highest national priority.
The same main elements and lines of research needed are likely to be common to many countries and at least at a regional (or eco-regional) level there may be considerable coincidence of interest in the principal species and genetic resources requiring study. More effective coordination of action, including research at the regional level has frequently been suggested but only infrequently achieved. The preparation of national research priorities in the context of the National Strategy for Conservation could assist more productive regional cooperation.
A further task in formulating the National Strategy for the Conservation of Forest Genetic Resources will be the definition of appropriate institutional structures to guide and coordinate subsequent action. The exact nature of the institutional arrangements will need to be decided in accordance with existing national structures and mechanisms. Action to formulate the strategy may best be taken by the national Forestry Department but the need to secure strong inter-sectoral cooperation and high level policy review indicates close involvement with, if not actually within, central government structures. An example is the adoption by the National Planning Commission in Nepal of the National Conservation Strategy Implementation Programme in that country. This is most likely to ensure the necessary inter-sectoral coordination and policy integration at a high level that is essential. However as an initial step the establishment of a National Genetic Resource Unit, as envisaged under the Tropical Forestry Action Programme, TFAP (FAO 1985b) may be sufficient, if an appropriate equivalent body does not already exist. The TFAP is the most appropriate existing international mechanism to assist the national sector review in all aspects, including the more appropriate appreciation of the capital value of the natural forest and its genetic resources. It is the failure to understand or to accept the use values and option values of genetic diversity in the national economy which has prevented the necessary investment in genetic conservation.
In addition to the undervaluation of the resource, and the associated lack of investment in its conservation and sustainable management, the principal deficiency in the approaches to management is the lack of information on the forest structure and dynamics. For effective sustainable management data are needed on the composition of each of the main forest types, the silvicultural characteristics of the principal species and of the others which may compete with them at various stages of their development, their regeneration behaviour, growth rates, and response to canopy opening, logging or silvicultural operations. In most cases even the basic knowledge of growth and yield of the principal economic species is lacing. Management for in situ conservation of genetic resources requires much of the same basic data on ecology and autecology that underlies attempts at silviculture in the natural forest, but with greater emphasis on breeding biology and genetic structure. Nevertheless a broadly-based forest inventory, as exemplified in the Ghana case study, accompanied by surveys of NTFP and of patterns of variation in the floristic composition of the forests, is of fundamental importance for both production genetic and conservation objectives. The inventory can also provide information on species distribution patterns, which are a first step in exploring intra-specific variation, to be included in in situ conservation strategies. The network of Permanent Sample Plots or continuous inventory plots required for production management can also be used for e.g. phenological studies and more fundamental research, possibly involving scientists from universities, both national and international see also Section 3.3).
There is frequently a wealth of unpublished data available from a variety of sources, from herbarium sheets to expedition records and academic theses, which could contribute to the information needed on forest composition, species distribution, phenology of flowering and fruiting and so forth. Modern computer-based approaches to information management can be used to store and assist the interpretation of such data, and to guide the efficient collection of additional information to fill the most important gaps (Jenkins 1988; Davis et al 1990). The use of Geographic Information Systems (GIS) can be a powerful aid in the definition and interpretation of species distribution patterns in relation to environmental variables and vegetation types. Similarly computer-based systems for handling taxonomic data have improved the accessibility and usefulness of information on genetic diversity in respect of both taxonomic groups (e.g. ILDIS: International Legume Database and Information Service) and geographical areas. The ILDIS system incorporates information on economic importance and conservation status, as well as botanical and vernacular nomenclature, vegetation types, references to maps etc (Jury 1991). The Botanical Research and Herbarium Management System (BRAHMS) developed at the Oxford Forestry Institute, U.K. has been designed specifically to handle data related to a forest genetics research programme (Filer 1991). Many organisations in tropical countries use GIS and other database management systems on microcomputer. In view of the importance of the efficient handling of data needed for in situ conservation a National Data Centre for this purpose should be a component in the national strategy. This can not only assist but also actively encourage the efficient collection of data from many sources and potential collaborators.
Such a Data Centre would assist coordination of action within the country and provide a link to the regional and international data bases such as that at the World Conservation Monitoring Centre (WCMC) Cambridge (U.K.), supported by IUCN, WWF and UNEP, and to the Forestry Department of FAO, which provides the Secretariat to the FAO Panel of Experts on Forest Gene Resources. An important activity of this latter Panel is the preparation and revision at its regular meetings, presently held approximately every 3 years, of global lists of species, by regions and operational priorities (exploration, collection, evaluation, conservation, breeding and use), most in need of action. At its Seventh Session, in December 1989, the Panel noted the need for more frequent and vigorous review of the priority lists. Close liaison and cooperation between the National Data Centres and the FAO Secretariat to the Panel would be an important element in this process.
National Data Centres should also have a key role in regional cooperation, for example in the project proposed for the Conservation and Rational Use of Central Africa's Forest Ecosystems, linking activities in seven countries involved. Similar cooperative action would be valuable in West Africa (Tufuor 1990b), Central America and other regions and sub-regions.
The fundamental principle in the selection of the management system for a particular area of forest, to take account of the needs for genetic resource conservation, is that it should be based on adequate understanding of the forest ecology, and the autecology of the principal component tree species of socio-economic value.
A central problem which has plagued attempts to achieve predictable results from management interventions in tropical forests has been the failure to match the operations to the actual nature and state of the forest and the site. This has been the main reason why successful silvicultural experiments, carefully executed, have often failed to translate successfully into large-scale practice over the diversity of conditions in the forest as a whole. The attempt to apply one given management system, either monocyclic or polycyclic, throughout the forests, and often to apply the same silvicultural treatments as a “blanket” prescription, without adequate attention to variation in forest types, associations and stages of development, can never be more than locally, partially and to a considerable degree accidentally successful. Except for areas where intensive “refinement” of the species composition of the forest may be consistently maintained through several felling cycles, the impact on the genetic resources of the forest is also likely to be accidental and at times irreversible. On the other hand, regeneration studies under a variety of systems in different countries have shown a general resilience of the forest composition, provided that logging is not succeeded by further catastrophic impacts on regeneration, such as fire or illegal cultivation of non-forest crops.
Available information on the genetics and variation of individual species, including the principal economic tree species in the tropics and sub-tropics, is generally inadequate to predict the effects of logging and silvicultural operations on their genetic resources, except in very general terms. However, as observed in previous sections, short cycles of logging and the indiscriminate use of heavy machinery, are likely to be more damaging to both species composition and reproductive systems than longer cycles (70 to 100 years). Similarly light selective logging, leaving a well-dispersed population of seed bearers of the principal economic species, is likely to be preferable from both view points to more severe disruption of the forest. The methods to reduce felling damage (topographic and stock mapping, tree marking, road planning and construction, directional felling, choice of equipment etc) can be cost-effective in economic as well as ecological terms. At the simplest level, therefore, careful planning and control of harvesting even without more elaborate management prescriptions, as practised in e.g. the Unités Forestieres d'Amenagement in the Peoples Republic of the Congo (FAO 1989b), is likely to serve both production and conservation objectives.
Beyond this level of management the financial and manpower constraints related to the low valuation of the natural forest cause increasing divergence between the degree of information and precision needed for the management of genetic resources, in tailoring operations to the actual forest condition, and the level of investment in management permitted by the economic calculations of costs, yields and discount rates. In addition to securing more appropriate levels of revenue, as in the Ghana case study, and applying them to forest management, additional value should be attached to the conservation of genetic resources in situ, to reduce the pressures for intensification of yield. Such pressures, operating both on the length of cutting cycles and through the concentration of growth into a few currently commercial species, necessarily conflict with wider conservation objectives, concerned with species richness, ecosystem conservation and option values. However the actual level of value to be assigned to the genetic resources must be assessed, and the appropriate compromise must be struck in respect of each forest or management unit, taking account of the National Strategy for Conservation.
The need for flexibility in management, according to the nature and actual state of the forest, is recognised at least in respect of timber production, in both the Malayan Uniform System, MUS (though often not implemented) and the Malaysian Selective Management System, SMS, which allows for the adaptation of management and possible silvicultural operations to the state of the populations of young trees eligible to form the next crop, after the effects of logging (FAO 1989c). The SMS prescriptions are also intended to take account of ecological considerations and these should include the conservation of genetic resources, as defined for a particular forest area, within a National Strategy for Conservation. Knowledge of the composition, ecology and silviculture of the forests, particularly in Peninsular Malaysia, is almost certainly better developed than that of any comparable area of tropical forest (e.g. Wyatt-Smith 1963; Burgess 1975; Ng 1978 and 1989; Tang 1987; Whitmore 1990; Appanah and Salleh 1991). The practice of liberation thinning to manipulate the performance of selected potential final crop trees, as practised initially in Sarawak (Hutchinson 1987), has been used with apparent success in several countries, notably in Cote d'Ivoire (Maitre 1991) and in Surinam (Graaf 1991) at least on an experimental scale. Such approaches can be used to favour different species or species groups according to the prescriptions made for a particular forest or compartment. This is easier to apply in the Malaysian forests, where there is a wide range of potentially marketable species, and a strong information base both for their management in the forest and their grouping for the market. However the same principle may be applied in forests less rich in economic species, if there are one or two common general purpose timbers with vigorous regeneration. This principle is being explored, for example, in Costa Rica, based on Pentaclethra macroloba to support the conservation of the populations of known, valuable species such as Cedrela odorata (Finegan pers. comm. 1991)1.
The implications of the long-term trends in the international trade in timber, discussed in Chapter IV, are that the most secure market for tropical timber is likely to be for high quality species for high-priced veneers, joinery, furniture, musical instruments or other special applications. Although the bulk of such trade may be small prices are likely to be high (ITTO 1991). Highly selective logging of species used for such purposes, most of which are likely to be slow-growing and characteristic of mature-phase forest, possibly in combination with harvesting of NTFP, could be compatible with the conservation of their genetic resources and other genetic diversity best conserved in mature-phase and climax forests.
At the other extreme the increasing acceptance, particularly for the domestic or regional markets, of a wider range of currently lesser-used species, including those with light, non-durable but treatable timbers, offers opportunities for other management models, also compatible with the conservation of genetic resources. These may include uniform systems, as in the strip shelterwood management system, operating on a pilot scale in the Palcazu valley in Peru (Hartshorn 1989), where early results indicate that it may be possible to retain a high proportion of the original tree species within a viable production system, with the support and involvement of local communities. The greater use of lesser-known species as an aid to conservation of the depleted resources of more valuable species, and the range of management actions which may be needed to achieve this, are illustrated in the Ghana case study.
The management of production forests in support of genetic resource conservation may be most effective in close conjunction with management of Protected Areas, such as National Parks. These provide a reservoir of seed and a haven for fauna involved in seed and pollen dispersal. Although as explained earlier quite small areas of unlogged forest may serve this purpose, for example in supporting adequate populations of frugivorous birds or small mammals involved in seed dispersal, in certain cases much larger areas are required. This applies e.g. to the role of elephants in natural forest ecosystems in Africa in the ecology and distribution of timber trees such as Tieghemella heckelii (Martin 1991). The association of the Bia National Park, in Ghana, with the adjacent timber production forest is a good example of this. At the same time the production forests can provide an effective extension of the range of species found in the Protected Area. The valuable principle of incorporating protection areas, such as the Virgin Jungle Reserves (VJR) in Malaysia, within the production forests is clearly a most important component of any National Strategy for the Conservation of Forest Genetic Resources.
1 B. Finegan, CATIE, Turrialba (Costa Rica).
It is at the level of individual forests, working circles and compartments, and through the preparation of detailed management plans, or working plans, that the principles of forest management and genetic resource conservation must be put into operation. To the extent that working plans for the forest are carefully prepared and scrupulously carried out this is a further instance of potential benefit to the conservation objective through their association with timber production. As stressed earlier many aspects of sustainable forest management, from inventory, growth and regeneration studies to responsible harvesting, should simultaneously assist genetic conservation objectives. This applies particularly to the provision made to secure satisfactory regeneration, for example through the timing of exploitation in relation to mass fruiting years or the retention of adequate numbers and distribution of seed trees in the absence of adequate regrowth of desirable species, as well as the avoidance of damage to soil seed banks.
The collection and validation of data on growth and the accurate forecasting of future sustainable timber yields is both essential for forest management and also of critical importance to conservation objectives. There are many examples of severe threat to the genetic resources of major timber species through over-cutting of forests on the basis of over-estimates of future levels of harvest, and through repeated “creaming” of the stand. These have sometimes been used to justify large scale industrial development which then creates an insatiable and destructive demand on the forest resources. This is an area where the interests of long-term sustainable forest management and the conservation of genetic resources closely coincide.
There are other aspects of management in which the need for care to conserve genetic resources goes beyond, and may at times even be seen to conflict with production objectives. As stated earlier it is neither possible nor necessary to attempt to impose conservation measures with equal priority and stringency in all production forests; to do so would weaken the support for the general concept of genetic conservation among forest managers, and invite widespread disregard for application of related principles in practice. Therefore realistic assessment of the situation in respect of each area of forest is essential, so that firm objectives, activities and criteria for monitoring their effects can be included in each working plan. Where the practices for sustainable forest management and genetic resource conservation closely coincide the prescriptions should apply in all production forests, and it is only necessary to refer to the additional importance of careful attention, for example to the restrictions on harvesting damage to regeneration or the importance of subsequent protection from fire, in the context of the National Strategy for the Conservation of Forest Genetic Resources.
In certain forest areas to be designated under the National Strategy for Conservation, additional measures will be needed. These will relate to the assessed importance of the forest in the conservation of the genetic resources of the principal species of known socio-economic value, lesser-known species, NTFP or particular vegetation or forest types. An important criterion will be the location of the forest in the overall species range, and in relation to environmental conditions. The importance of conserving a wide range of provenances has been established earlier, and this may be achieved to a large extent through the application of sustainable forest management throughout the Forest Estate. However particular care may be needed where the species occurs under more extreme environmental stresses, related to climate, soil, altitude etc, or at the edges of its natural range. Not only are these populations likely to be genetically distinct, through adaptation to the local environments, but they may also be more vulnerable to disruption through disturbance, which could radically reduce the long-term viability of such populations. Special consideration should be given to these marginal populations through limiting the intensity of logging, and through intensification of research into their genetic structure and reproductive biology.
The other main criterion in selecting areas for special consideration relates to the production management systems in general use in particular forest formations or vegetation zones. If, as is most likely, these tend to favour pioneer or early gap-phase species, and thus to reduce the opportunities for the maintenance of satisfactory breeding populations of mature-phase species, special attention will be needed to conserve the genetic resources of this latter stage of the forest's development. The extent to which this should be done in production forests will depend on the role and de facto contribution to genetic conservation of existing Protected Area systems but it is unlikely that production forests alone could provide adequate levels of geographical and ecological coverage for species and populations concerned.
Genetic resource conservation should be an important factor in the design and operation of working circles within the forest. Hitherto the allocation of areas to a protection (conservation) working circle has been based almost invariably on considerations of accessibility, steepness of slope, adverse geological or drainage condition etc. rather than their value for genetic resource conservation. The protection of special sites such as streamsides is desirable for several reasons, including conservation of biological diversity. However the siting of conservation areas such as Virgin Jungel Reserves (VJR's) should attempt to conserve associations representative of the diversity and genetic resources of the forest as a whole, or of the particular forest type. This is likely to frequently conflict with immediate production objectives but the more intensive the form of management in the remainder of the forest, the more valuable the diversity and genetic resources of the VJR or other Conservation Area may be. From the viewpoint of the conservation of the most desirable economic species the practice of leaving small pockets of unlogged forest, and well dispersed seed trees, throughout the production areas is likely to be needed in addition to the allocation of a larger area, such as an entire compartment, as a VJR.
The real problem commonly lies in reconciling these various objectives with the interests of the timber concessionaire. The provisions recommended to secure real interest on the part of the timber harvester in the regeneration and long-term sustainable management of the resource should also be conducive to conservation of the genetic resources of the principal economic species. However to conserve desirable option values of the genetic diversity, which have no evident, present-day market value, some additional incentives will be needed. The most promising concept may be the setting of high concession rents, together with clearly defined conservation objectives, related for example to the omission of selected “pockets” of forest from the harvesting operation. To the extent that the conservation objectives were met there could be a refund of a proportion of the fees, or conversely for gross violation the imposition of penalties under the contract. It has been suggested that ideally concessions should not be granted purely for timber extraction, but as a contract between the government and the private sector to manage the forest for a range of products and benefits, including timber (Johnson et al 1991).
In all aspects of forest management and conservation the failure to comply with the prescriptions and conditions set has been a frequent cause of damage to the growing stock, and particularly its capacity for regeneration. Close monitoring of operations, both to judge their conformity with prescriptions and to assess their effect relative to the declared objectives, is in the common interest of both sustainable production and genetic resource conservation. It may also be an important aspect of “forest accounting” designed to monitor the condition of the resource and to evaluate the standard of management. This will include aspects involving scientific criteria, for example in regard to genetic resource conservation, as well as others related to technical and socio-economic objectives. Criteria for monitoring should be clearly set in the management plan, taking account of the objectives set under the National Strategy for the Conservation of Forest Genetic Resources.
The genetic resource conservation value of a concession area, as determined under the National Strategy for Conservation, should be used in assessments of the quality of sustainable forest management. Systems and criteria for the assessment of sustainability in forest management will be needed at least in respect of forests managed for the export of timber, in accordance with the ITTO guidelines and target mentioned above (ITTO 1990). There might be positive incentives through the market for conforming to the accepted guidelines, which will include consideration of the impacts on biological diversity in the forest. In any case it is in the national interest to ensure that the objectives set under the National Strategy for Conservation in respect of forest genetic resources are achieved. In both the assessment of the genetic resource value and objectives in a particular forest and the setting of criteria by which to measure the achievement, specialist advice of forestry geneticists may be needed. This is most likely to be necessary if management action is required to conserve the genetic resources of given target species or populations, which may involve considerations of population genetics and viable population size. Other specialist advice in regard to forest ecology, the role of “keystone” species in the functioning of the forest and the genetic systems of economic species may also be required.
As indicated earlier, and emphasised in most recent reviews of tropical forest management, the involvement of local communities situated in and around the forest in aspects of forest management is likely to be increasingly essential to long-term conservation objectives. The concept of joint planning and management, operated differentially according to the management objectives of the different zones, as outlined in the India case study, allows for a contractual relationship with local people, without weakening the legal status or government control over the forest land. Such a careful balance between the long-term security of the genetic resources in those areas requiring strict protection, and the sustainable development of a variety of indigenous trees and other plants in appropriate management zones, provides wide possibilities for genetic resource conservation. However to an even greater extent than the management of the natural forest for timber production alone such multiple-use systems are likely to require specific formulation in the particular ecological and socio-economic situation, and incorporation of the full range of concerns in the management plans of the forest concerned.
The management of areas of production forest acting also as a “buffer zone” to a National Park or other Protected Area was discussed in Chapter IV. The most important aspect is for the management of the two kinds of area to be fully integrated and under single effective control within one management system. This may require special administrative arrangements if primary responsibility for production forest on the one hand and the fully Protected Area on the other, come under separate ministries. However the same principle of joint planning and management, with clear objectives and management plans for each zone, should apply. The efficient management of the genetic resources of key economic species represented in a National Park or other Protected Area, may require specific management interventions, for example the collection of seed or other propagating materials for ex situ action, or liberation thinning to favour the development of young trees of the species targeted for conservation in situ. Such activities may (at times properly) be contrary to the general Park regulations. This could be the subject of examination under the National Strategy for Conservation and provision could then be made by amendments to laws and regulations to permit action for the conservation of forest genetic resources, with appropriate safeguards and restrictions, in accordance with the National Strategy for Conservation.
International concern for the tropical forests is certain to continue and to deepen, as the forests are further reduced. This concern, and the allocation of resources to the extent needed to conserve the existing natural ecosystems and their component species, will come too late to retain them intact in many areas in many countries. However except where large areas are severely altered, for example by fire or continuous intensive cultivation, valuable genetic resources are likely to survive under sustained forest management systems; such resources are invaluable as the basis for the regeneration and/or restoration of functioning natural forests, in various forms and for a variety of uses.
The Protected Area network, which must be the core of ecosystem conservation, is likely to prove increasingly inadequate to meet long-term objectives for the conservation of genetic resources. In addition to its limitations in geographical coverage, restricted often arbitrarily by other demands on land, it is likely to be further limited in terms of environmental diversity by the size, shape and management practices in each reserve area. Dynamic conservation, in a world in which future human needs and climatic conditions must be increasingly uncertain through successive generations, requires more than the attempt to prevent genetic erosion and to retain a fixed current state of diversity. It implies conserving the evolutionary process, to advance and develop ecosystem diversity, and targeted genetic resources, in directions which seem likely to prove most useful, and to retain a wide range of options to continue this process into the very distant future. Within this concept management actions, including harvesting and silvicultural activities, can be creative of genetic diversity, if they are freed from past pressures towards “blanket” uniformity, centred on a few species with minimal reinvestment of resources - skills and finance.
Logging operations alone, if they are neither too intensive nor too frequently repeated, but follow known principles for good practice (Dykstra and Heinrich 1992) are likely, in initially diverse tropical forests, to leave levels of complexity in species composition and plant associations which, although they may not exactly follow previous patterns of distribution, can maintain or even increase overall genetic diversity. Given adequate information on the patterns of such diversity between compartments (or in critical cases sub-compartments), as well as across larger forest management units, and within the National Forest Estate as a whole, and given the continued development of advanced systems for handling and interpreting data, future management systems could be tailored to serve dynamic conservation strategies, at the same time as they meet the needs of industry for predictable flows of raw materials. This, however, will require greater coordination of management planning at the national level, as well as the integration of conservation concerns in the management prescriptions of both production forests and the Protected Area network, under a coordinated, National Strategy for the Conservation of Forest Genetic Resources.
At national level the combination of a comprehensive National Forest Inventory with a detailed botanical survey, as exemplified in the Ghana case study (see Part II), provides a good basis for such strategic planning, in terms of geographically-related data on the distribution of many tree species and plant associations. At the level of Forest Management Units diagnostic sampling by compartments, designed to collect information to support genetic conservation strategies, as well as forecasts of harvestable production of timber and other commodities, could provide much information, to adequate levels of precision (often presence or absence rather than volumetric or qualitative data), at acceptable cost (Hutchinson 1991).
The Malaysian Selective Management System (FAO 1989c) allows for silvicultural operations to be tailored to the actual condition of the forest after logging, taking account of environmental objectives. It is likely that, given responsible harvesting planning and control, largely accidental influences on species composition in the advanced regeneration, superimposed on site-related differences, will leave considerable diversity within individual forest reserves, and even more over the National Forest Estate as a whole. The coordinated management of this existing diversity might go a long way to achieving the objectives of dynamic conservation, linked to productive use of the forests. However, in some areas, carefully targeted silvicultural operations might be needed to conserve the genetic resources of selected populations of trees of socio-economic importance, or to maintain given species richness or ecosystem diversity. This might involve management decisions to prolong felling cycles or leave selected trees or patches of forest unlogged, as well as some silvicultural interventions, for example to release the advanced regeneration of selected individuals of chosen species in particular areas, as part of a coordinated national strategy. The prescriptions for each area to be treated would take account of its comparative value in terms both of production and genetic conservation.
Some areas, particularly in the boundary zones of production forests, might be devoted to intensive management of non-timber forest products for national use or local community benefit. This could extend the overall diversity of management systems, with the introduction of the influence of cultural diversity on forest composition, while maintaining the principle of linking conservation with productive use. The underlying principle, coordinated in application at the national level, must be the management of diversity through planned diversification of management.