K. Isik, F. Yaltirik and A. Akesen
Kani Isik is with the Biodiversity Research, Development and Application Centre at Akdeniz University (MED-BIOME), Antalya, Turkey.
Faik Yaltirik and Aytug Akesen are with the Faculty of Forestry, University of Istanbul. Bahceköy, Turkey.
An adaptation of the position paper for the Eleventh World Forestry Congress, "Forests, biological diversity and the maintenance of the natural heritage ".
Protected areas are an essential component of In situ conservation of forest biological diversity. In the photo: a conservation area In Eritrea
The following statement in Agenda 21 of UNCED clearly defines the current problems of forests and biological diversity:
"Forests worldwide are being threatened by uncontrolled degradation and conversion to other forms of land uses; influenced by increasing human needs; agricultural expansions; and environmentally harmful mismanagement including: lack of forest fire control, anti-poaching measures, unsustainable commercial logging, overgrazing, air-borne pollutants, economic incentives, and activities of other sectors of the economy. The impacts of loss and degradation of forests are in the form of soil erosion. loss of biological diversity, damage to wild habitats and degradation of watershed areas, deterioration of the quality of life, and reduction of the options for development."
Evolution of the concept of sustainability in forest management
Starting with the Neolithic age, people began to clear forests to obtain open land for settlement and for grazing of animals. In the succeeding millennia, the forests and the landscape were further modified by humans for uses in various types of agricultural activities. As the human population rapidly increased after the eighteenth century, pressures on forest lands also increased, especially in the Mediterranean zone and in central Europe, followed by soil erosion and the degradation of many valuable habitats. Amid these activities, fundamental methods of forest management were developed in central Europe, specifically in Germany (Tabel, 1995). Consequently, many principles of sustainable forest management have their roots in the eighteenth century. Sustainability, then, is not a new concept to forestry. It has traditionally been considered as deciding the level of timber harvest for human use (SAF, 1992).
In addition to wood products, other assets related to the ecological value of forests have been increasingly recognized in the second half of the twentieth century.
Forests are the homes of a great diversity of species of plants, animals and other organisms. Many agricultural plants and domesticated animal species originate in wild relatives which still inhabit forest lands. Many species in forests provide people with food, timber, fuelwood, medicine, various other raw materials for industry, and fodder for animals. In addition to these direct socioeconomic inputs, forests and forest lands perform a variety of complex ecological services such as oxygen production, carbon dioxide fixation, mineral and water cycles, soil and water protection, climatic regulation and so on. In addition, forests offer opportunities for tourism, recreation and inspiration.
The influences of many of these services and benefits are far beyond the regional and national borders of the forests and nations involved, both in space and time. The critical point is that the outputs from these services are necessary for a healthy and hospitable human environment; and still further, each of these services can neither be performed nor produced on a large scale by human technology.
Tropical rain forests are of special interest on account of their important global influences. They are remarkable both in regard to the quantity and to the diversity of life they support. They are more complex than both temperate and boreal forests in their structure and functions. Tropical rain forests cover only 7 percent of the earth's land area, yet they are estimated to contain at least 50 percent, and possibly as high as 90 percent, of terrestrial species (Rodgers, 1997). The rich diversity of tropical forests can be illustrated by an example: in Peru, nearly 300 species of trees have been recorded on one single hectare. In contrast, there are only 50 indigenous tree species in the whole of Europe north of the Alps (Drewery, 1994).
Objectives of contemporary forest management are increasingly based on the so-called "ecosystem management principles" (see Sexton, Johnson and Szaro, 1997). For example, Kaufmann et al. ( 1994) describe the United States Department of Agriculture Forest Service's objective as "the creation of healthy, productive ecosystems through an ecological approach that incorporates needs and values defined by social, physical, economic, and biological criteria". The ecosystem approach in forest management, therefore, implies ecologically stable, healthy, diverse and sustainable forests. The challenge for foresters is to balance economic development and biological diversity (SAF, 1992). Forest management strategies need to consider biological diversity, ecosystem processes and long-term site productivity to maintain and improve human well-being on ecologically and economically sustainable bases.
More than 150 governments signed the legally binding Convention on Biological Diversity at the 1992 Earth Summit in Rio de Janeiro. By ratifying the Convention, the involved parties accept the responsibility to safeguard the genetic material, species, habitats and ecosystems that make up the natural world.1 Article 6 of the Convention sets out the general measures for conservation and sustainable use of biological resources, calling for development and implementation of national strategies, plans or programmes.
The following quotation, taken from the Foreword of the Global Biodiversity Strategy (WRI/IUCN/UNEP, 1992), indicates the position of the leading conservation organizations.
(1The convention was ratified by Turkey on 27 December 1996)
"Development has to be both people-centred and conservation-based. Unless we protect the structure, functions, and diversity of the world's natural systems- on which our species and all others are dependent development will undermine itself and fail. Unless we use Earth's resources sustainably and prudently, we deny people their future. Development must not come at the expense of other groups or later generations, nor threaten other species' survival."
Biodiversity is the totality of genes, species, ecosystems and ecological processes in a region. Thus, biodiversity consists of four elements: i) genetic diversity; ii) species diversity; iii) ecosystem diversity; and iv) process diversity (SAF, 1992; IPGRI, 1993; Isik, 1997).
Genetic diversity, intraspecific diversity and between species diversity, is the sum of total genetic information, expressed by the genes of individuals. Normally, there are many individuals within a species; all - except identical twins (and clones) - are genetically unique. The presence of different genes and alleles, and their differential combinations among individuals, produces variability in a given trait. Different combinations and different frequencies among populations of a given species produce variability among populations, for example, differential resistance to diseases, to drought and to extreme temperatures. The genes that control these characteristics are passed down from generation to generation, forming new genetic combinations and new variability at each step. Genetic diversity within species provides the potential to adapt to new or changing environments and to respond to new human needs. As long as there exists rich genetic diversity within a species, plant geneticists can select and breed new varieties to respond to changing needs and conditions (lPGRI, 1993; Isik, 1996). Genetic diversity can be measured by methods employed in population genetic and, in the case of variation at the molecular level, also by some new techniques such as electrophoresis, molecular markers and gene sequencing that have been developed in recent years (Cheliak, 1993).
Species diversity refers to kinds and numbers of species present. The number of species present on earth is estimated somewhere between 5 million and 80 million, although only 1.6 million have been described. Popularly, biodiversity is often thought of only as species-level diversity. This is an incomplete assessment in terms of sustainability of renewable natural resources. While defining species diversity, one must take both "genetic" and "taxonomic" diversity into consideration. Genetic diversity within species, in turn, is the main concern of genetic resource programmes, and it is the source of adaptability and evolution in changing environments.
Ecosystems are composed of living and nonliving components, including their edaphic (soil) and biotic properties, and are influenced by climatic and topographic factors. Ecosystem diversity stimulates progress, first in habitat and then in species diversity. As a result, ecosystem diversity provides differential habitats for different species to live, each species adapting to its own ecological niche, and eventually forming their own climax communities. It is more difficult to measure ecosystem diversity than genetic and species diversities mainly because the boundaries of ecosystems are relative and without definite lines. Nevertheless, by using certain consistent criteria, ecosystems can be defined and classified at the local, regional and global levels (Zuomin, Ruimei and Youxu, 1997; Sexton, Johnson and Szaro, 1997).
"Process" or functional-level diversity
Process diversity is an evolutionary outcome of ongoing interactions among living and nonliving things in an ecosystem. The best known of these interactions among living components are predation, parasitism and mutualism. Ecological services (such as water, carbon dioxide, oxygen and nitrogen cycles, decomposition, etc.) are the result of processes among living and non-living components. These are collectively called ecological processes of an ecosystem. Process diversity, then, interconnects living and non-living elements of an ecosystem and maintains the existence of various components of biodiversity in mutual harmony. thus constituting fundamental parts of biodiversity in the system.
The number and area of notional nature reserves needs to be Increased. In the photo: yellow-billed storks on the shores of Kazinga Channel, Ruwenzori National Park, Uganda
In order to maintain biodiversity, the factors that threaten biodiversity should first be recognized and clearly defined. Any condition that impairs the functions of any of the components of biodiversity is a threatening factor. The main factors that may cause the loss and/or decline of biodiversity at the local, regional, national and/or global scales can be classified as follows (WRI/IUCN/UNEP, 1992):
· Habitat loss and fragmentation. Many natural ecosystems have been eliminated or broken into small pieces, losing much of their biological diversity and biological integrity.
· Overexploitation. Rapid population growth and improvement in harvesting technology have led to unsustainable utilization of plant and animal species, sometimes to the point of extinction.
· Pollution of soil, water and atmosphere. Pollutants degrade and destroy habitats to varying degrees, with subsequent reduction and even elimination of species.
· Introduced species. A new species, which is not co-evolved with other elements of a recipient ecosystem, may threaten indigenous species (Vitousek et al.. 1987).
· Global climatic change. The widely discussed global temperature rise of some 1° to 3°C during the next century, with an associated rise in the sea level, would displace the optimum distribution range of land species towards the poles, and upwards on the mountains. The genetic diversity of many species may not be able to keep pace with rapid changes in the environment of this type and they would become extinct (Schnider, 1989; Peters, 1990).
· Industrial agriculture arid forestry. New plant and animal varieties developed by modern breeding programmes are replacing so-called "field varieties" and/or "indigenous races". Unless genetic conservation considerations are built into such programmes, there will be a subsequent loss of adapted genes and gene combinations. Further, such new varieties, which are selected for a few desirable characteristics, usually exhibit low genetic diversity and a narrow genetic base, making them easily susceptible to diseases and pests.
Biodiversity at the gene, species and ecosystem levels should be conserved and maintained for sustainable development (Namkoong, 1991). Ecosystem diversity provides different habitats for different species that inhabit them, enriching species and process diversities within a given ecosystem. Genetic diversity provides adaptability and evolutionary potential for species that carry those genes (Ehrlich, 1990). Therefore, components of biodiversity should first be maintained, then they should be studied and, finally, based on this understanding, they should be used sustainably (WRI/IUCN/UNEP, 1992).
Acacia In bloom In the Congo
Genetic conservation (in situ and ex situ)
Protecting species and their genes can be done best through protecting them within their natural habitats, eventually within ecosystems where they live with other species (Ledig, 1986). In situ (within their natural environment) conservation is considered as the best solution for the conservation of genetic resources, because it maintains the evolutionary potential and adaptive capacity of the involved populations. Both target genes and co-adapted gene complexes with associated biological communities are conserved within their native ecosystems.
As a first step for in situ conservation, the degree of variability and genetic architecture, distributions, locations, sizes and numbers of populations should be determined. Each forest stand is unique in its genetic composition because each represents the outcome of adaptations to sets of site-specific environmental conditions. This is especially true in forest tree species growing under heterogeneous environments.
A common method of in situ gene conservation is to conserve representative populations growing in representative habitats, in a systematic manner (Koski in FAO, 1996). It is also important to conserve genetic variation in marginal and isolated populations which may possess specific genes for desirable traits (Ouédraogo, 1997).
National parks, nature reserve areas, natural monuments, nature parks, habitat/ species management areas, gene management zones (managed resource protected areas), gene conservation forests, specially protected environmental regions and other similar sites are the main in situ areas.
All available alternatives should be utilized to maximize the lands for biodiversity conservation purposes. For example, Krishna and Shankar (1997) describe how local people in India have protected certain sacred groves for centuries. They suggest that such traditional practices should be complemented by appropriate scientific inputs for conservation, to help local people live harmoniously and sustainably with nature in the future.
Conservation of genetic resources and biological diversity should also be incorporated into forest management, in forests managed for protective and for productive purposes and into plantation and tree improvement programmes (see also FAO, 1993).
Depending on the kind of genetic materials, ex situ (out of natural habitat) conservation of genetic resources is accomplished in arboreta, botanical gardens, ex situ conservation stands, provenance and progeny tests, seed orchards, clonal archives, tissue culture, seed, pollen and DNA storage banks (e.g. Bonner, 1990). In spite of the diversity of opportunities in ex situ gene conservation, a major constraint is the instability of funds for long-term maintenance of genetic resources conserved ex situ. Further, genetic material preserved under artificial facilities is more likely to be subjected to selection, often quite different from natural conditions under which the original populations evolved (Ledig, 1986). Whenever possible, ex situ methods should also be applied as an additional insurance against genetic losses on in situ sites.
Laboratory tools used for in vitro research
Forest genetics and tree improvement activities
Forest geneticists and forest tree breeders use genetic material, or germplasm, of trees to improve quality and quantity of forest products (Zobel and Talbert, 1984; Ahuja and Libby, 1993). They select and breed trees that inherit genes for desirable traits, for example, rapid growth, good wood quality, resistance to disease, drought, cold, pollution and other adverse environmental conditions (e.g. Ziehe and Hattemer, 1987; Simpson and Ades, 1990; Namkoong, 1991; Altman et al., 1996). Forest geneticists and tree breeders in different countries are involved in various phases of conservation and management of forest genetic resources (Falk, 1990), including the establishment of gene management zones, seed production areas, seed orchards, clonal banks, pollen, seed and DNA storage facilities (Miller, 1993).
Biotechnology has made significant contributions in genetic studies in forest trees (Haines, 1993; Huang, Karnosky and Tauer, 1993; Watt et al., 1997). Both tissue culture techniques and molecular methods have been applied on many important forest tree species. Examples include: germplasm conservation using tissue culture and cryopreservation techniques (Miller, 1993), DNA storage, genetic engineering (Sederoff and Stomp, 1993), study of distribution and extent of genetic diversity (Kaya and Neale, 1993; Boydak et al., 1997), identifying and detecting genotypes by molecular markers (Cheliak, 1993).
The potential of biotechnology must be used with caution. Agenda 21 of UNCED makes specific provisions for the "environmentally sound management of biotechnology". Although new molecular techniques allow a greater diversity of genes to be introduced into organisms, the relative lack of information on what such organisms and such novel genes will do in the environment and their effects on the existing biodiversity argue for a conservative approach to any wide application of biotechnology in the field (Wrubel, Krimsky and Wetzler, 1992). International cooperation is needed to set safety measures in biotechnological applications (Commandeur et al., 1996).
Local people, foresters and scientists could combine the merits of agroforestry technologies both to support local people economically and to enrich biological diversity of a farm ecosystem (Altieri, 1991; Drewery, 1994).
Provided they do not compete with, or replace, certain native plants, well-adapted introduced tree species can add socioeconomic benefits and diversity to forest and plant communities and local ecosystems. Successful examples of these are Douglas fir in central Europe, Pinus radiata in Chile, South Africa, Australia and New Zealand, Eucalyptus spp. in the Mediterranean ecosystems and in Brazil (Eldridge, 1990; Libby, 1990; Bergschmidt, 1996). However, there have been more failures than successes in the introduction of exotic species, owing to insufficient prior testing and subsequent pest damage, damage caused by adverse climatic conditions (Zobel and Talbert, 1984) and/or unpredictable and damaging changes in the food chain patterns in local ecosystems.
The influences of forests and biodiversity are global, reaching far beyond the national borders of any nation, both in space and time. Therefore, international cooperation is essential, particularly among those nations that share a similar ecosystem and species. The Convention on Biological Diversity emphasizes the need for international cooperation to facilitate the exchange of information relevant to the conservation and sustainable use of biological diversity. There are a number of international organizations involved in biodiversity conservation, including the UN agencies FAO, UNEP, UNESCO; some centres of CGIAR, notably, IPGRI (including the European Forest Genetic Resources Network [EUFORGEN] coordinated by IPGRI), CIFOR and ICRAF; some international and national non-governmental organizations, such as IUCN, WWF, IUFRO and WRI (USA); and bilateral aid agencies such as GTZ (Germany) and others (see also Ouédraogo, 1997). These agencies and organizations are active in assisting countries in the planning, organization, exploration, funding and implementation of biodiversity and gene conservation activities of global importance.
In addition to in situ conservation and several other land use measures indicated above, additional action in forest lands has to be taken in order to maintain and improve the conservation and sustainable use of biological diversity. Depending on the status of forest lands, the following actions, which are technically and biologically feasible, could be suggested. Some of these measures may be applicable only for conditions in Turkey (with which the authors are personally familiar) (Isik, Kaya and Atalay, 1995; Karaca, 1997). Most, however, could have worldwide applications (see also Khan, 1997).
Agroforestry entails the maintenance of a high level of biodiversity. In the photo: a buffalo pasture under dagame trees In Peru
In national parks (NPs) and nature reserve areas (NRAs):
· Additional NPs and NRAs should be identified and designated to represent each of the major ecological zones, in such a way that existing and proposed NPs and NRAs form a systematic biogenetic reserve network.
· "Scale effect" should always be taken into account in designating NPs and NRAs. The area of land, for example, required for the sustainable survival of a herbivore species is much smaller than that of a carnivore species.
· Whenever possible, habitat corridors should be established to connect reserve areas for wildlife conservation.
· Management plans for NPs and NRAs should be reviewed and updated in view of national and global biodiversity objectives.
· Ecotourism and recreational activities should be managed to minimize behavioural and breeding disturbances to fauna caused by invasion of their territories by human species.
· New management policies and programmes should be adapted to ensure the participation of local people in protected area and buffer zone planning.
· Research programmes should be conducted to determine features of biological resources and their potentialities in NPs, NRAs and other forest lands as a basis for sustainable management of the species in question (e.g. Yaltirik, 1972).
· Programmes should be organized for continuous training and education of protected area staff and local people.
In degraded forest lands:
· Degraded forests should not be considered as "land banks" from where additional agricultural, pastoral, residential and/or industrial lands can be acquired. Rather, degraded forests should be rehabilitated and should be regarded as security valves for the ecological health of nearby communities.
In production forests:
· Silvicultural, administrative and social forestry interventions should be improved in parallel with improving the conservation of biodiversity. In this regard, the size of forest management units placed under the responsibility of the person in charge of forest management should generally not exceed the "European standard" of about 5 000 to 7 000 ha, in comparable conditions.
· Harvesting, logging, thinning, pruning and transportation activities in production forests should be reviewed and modified in view of national biodiversity objectives. Management plans and their implementation in forest lands should take into account not only the target forest tree species, but also other organisms contributing to healthy biodiversity.
· Many animal species dwelling in forest lands require different habitats at different times (day versus night, winter versus summer) and/or at different stages of their life cycles. Maintenance of habitat diversity is of vital importance for such species. A mosaic habitat structure should be encouraged in forest lands, with mixtures of young and old trees, broad-leaved and coniferous trees, small meadows and dense understorey vegetation.
· Organisms generally require stability and tranquillity in their habitats. Clear-cutting activities on large areas, in particular, cause sudden changes in many physical, microclimatic and biological elements of a forest ecosystem. Harvesting methods such as selective cuttings, cuttings in small groups, patches, alternative strips and progressive strips should be used if considered suitable to meet the stated biodiversity objectives.
· Logging residues should not be led to accumulate near stream and river banks. After decomposition, such materials along the waterways cause the physical and chemical qualities of waters to deteriorate, subsequently disturbing habitats and aquatic plant and animal species.
· Some dead trees and logs should be left standing in the forests, provided they do not harbour potential epidemic forest insect and disease species. Dead trees and lying logs play an important role in the maintenance of a healthy food chain in a forest ecosystem and also provide feeding, nesting and breeding habitats for many beneficial forest insects, birds (i.e. woodpeckers) and mammals (i.e. martens). A few old and taller trees should also be left scattered systematically throughout forest lands. Such trees serve as nesting and perching grounds for different bird species.
· Legal and administrative bases should be provided to secure the participation of local people in the establishment, care, management, harvesting and marketing of forest plants and products. Local people should be trained to utilize these products most economically.
· Projects should be developed to construct small reservoirs, terraces and flood control barriers along the streams and rivers in forest lands, especially in steep mountainous areas. Such constructions, in addition to preventing soil erosion and improving land and forest biodiversity, will create income opportunities for local people.
· Representative natural forests should be designated and managed on different climatic and elevation gradients across the country as "gene conservation forests", "genetic management units" and/or "seed stands". Seed stands should be selected and designated to represent each species in each of the major ecological zones.
· Biological control techniques should be applied to avoid forest epidemics; research should be encouraged on biological control agents, specifically on parasitic and predatory insects, insectivorous birds and allelopathic plants that could also have insecticide potentials, and research findings should be transferred rapidly to practical applications.
In reforestation and afforestation sites:
· Mixed forest as well as monoculture plantations should be considered, including multiple-purpose species such as Pseudoacacia, chestnut, walnut, bay tree (laurel), carob and (where appropriate) various grass and pasture species in mixtures.
· Plantations of mixtures of nectar, fruit and seed-producing plants should be encouraged together with wood-producing trees. These plants, besides providing aesthetic and other amenity values, would serve as shelter and as feeding and nesting grounds for wildlife.
· Alternate patches of "biodiversity strips" and/or "biodiversity pockets" should be established, as well as diverse microhabitats in and along the plantation sites. Such areas could be occupied by annuals and bushy perennials to provide fodder, fruits and seeds for certain animals in the forest ecosystem.
· Natural regeneration should be encouraged, wherever possible, in forest openings. Care should be taken to avoid introducing non-native species to an area unless species and/ or provenance trials prove them to be appropriate, both individually and within the prevailing ecosystem. The most effective natural regeneration methods should be determined through research for woody as well as non-woody species in their native habitats.
In special environmental protection areas (SEPAs):
· Unique ecosystems with high aesthetic, historical, ecological and geological properties have been under severe human pressure in recent years in Turkey. Some of these ecosystems have been designated as SEPAs, and special laws and regulations have been passed for these lands. Although emphasis on these areas is on the protection of ecosystems as a whole, specific action should also be taken to protect habitat and species diversities. Specific zones should be distinguished, and the carrying capacities for each zone should be determined for the most suitable land use objectives. Existing laws and regulations on SEPAs must be strictly applied and monitored.
Other actions to be taken:
· Existing laws related to forestry, environment, natural parks and biological conservation should be carefully reexamined in view of national biodiversity objectives. This becomes urgent if a country has already ratified the Convention on Biological Diversity or other international agreements and national commitments.
· Programmes should be developed to determine the most effective reproducing, growing and harvesting techniques for wild plant and animal species that produce special products which may have high economic value. Silvicultural and other cultural measures should be examined and implemented to improve their quality and quantities.
· Agroforestry activities should be encouraged and expanded in villages located both in forest regions and agricultural zones.
· Special measures should be taken to protect sensitive and fragile ecosystems.
· Ecotourism activities compatible with biodiversity conservation objectives should be encouraged (Akesen, 1992). Existing legal, administrative and technical measures should be strictly applied to improve biological integrity and natural structures of NPs and NRAs. Hunting and fishing must also be regulated in accordance with existing laws.
Biodiversity conservation must first be based on available biological information. Some of the biological topics that need to be further clarified are listed below:
· Development of procedures to identify research and species priorities in biodiversity conservation (see Rodgers, 1997; Mátyás, 1997; Lammerts van Bueren and Duivenvoorden, 1997).
· Detailed ecosystem or vegetation classifications, determination of forest types or ecological zones (both at regional and global scales) for assessing the representativeness of the existing and future protected area network (see Irenmonger et al., 1997; Zuomin, Ruimei and Youxu, 1997).
· Determination of the effective population size for target species and determination of the impact of inbreeding depression on the evolutionary potential of the taxa involved.
· Scientific information to establish and apply sustainable management strategies (see Howard, 1997).
· Improvement of in vitro techniques to store germplasm.
· Determination of physiological and biochemical mechanisms controlling adaptation to stress and disease conditions; identification of genes and/or gene complexes that control such characteristics.
· Development of concrete measures to determine the adaptability of species and populations to changing conditions (see Mátyás, 1997).
· Monitoring and evaluation of genetic erosion.
· Determination of probable impacts of biotechnology and novel genotypes (transgenic plants) in ecosystems.
The challenges associated with conservation of biological diversity are not only biological, but also political, economic, social and even ethical in nature. Conservation measures are implemented by local governing bodies, politicians, practitioners, biologists, foresters, agriculturists, engineers, rural sociologists and economists. Therefore, coordination among all parties involved is necessary.
Biological resources are the essential basis for life on earth. The fundamental ecological, economic, aesthetic and ethical values of biological resources have been recognized in religion, folklore, art and literature since ancient times. By the start of the nineteenth century biological resources, including forests, were freely available in many countries for those who wanted to utilize teem. Over the past three decades - since humans viewed the earth from the moon - it has been rapidly realized that the carrying capacity of earth and the biological resources on it are quite limited. Scientists, politicians, governments, industry, international organizations and the general public are increasingly concerned about the depletion of biological resources. It has been generally recognized that our social and economic development depend completely on their availability, and their maintenance.
The Convention on Biological Diversity, signed by a large number of countries at the UNCED Conference in Rio de Janeiro in 1992, was a turning point to take actions to maintain biological resources sustainably. More than 150 nations agreed that plans and strategies should be developed, and efficient and constant actions should be taken to conserve and improve biological diversity on earth. Forest ecosystems, especially in the tropics, are the most important element of terrestrial biodiversity. Forest lands extend over a great diversity of ecosystems, harbouring a rich diversity of species and genes, showing longlasting influences, far beyond national and even continental borders. So governments, international organizations, conservation groups and scientists, who are involved in conservation, should give priority to biodiversity conservation on forest lands. The first prerequisite to conserving forest biodiversity is to have strong public support with an informed conservation lobby and stable government policy. Accurate information (on the biology of species and on the nature of ecosystems) is essential for determining conservation strategies, making plans, taking action and maintaining genes, species and ecosystems. Protecting biodiversity can best be accomplished through protecting species within their natural habitats (in situ conservation) with ex situ conservation a necessary complement.
Many other actions, collectively or individually, can be taken in forest lands to improve biological diversity at all levels. Local people should be trained and given increased opportunities (albeit under the close control of the authorities concerned) in the management, implementation, marketing and sustainable use of forest biological resources. Initial financial support for biodiversity conservation plans should usually be obtained by government incentives and international sources. Subsequent financial support should come from those who benefit most from the biological resources. Unless direct beneficiaries pay their portion of the cost, maintenance and sustainability of the resources will be impaired.
Ahuja, M.R. & Libby, W.J., eds. 1993. Clonal forestry. I: Genetics and biotechnology. Berlin, Germany, Springer-Verlag. 277 pp.
Akesen, A. 1992. Ormancüluk-Turizm Ülißkileri Çerçeversinde Akdeniz Orman Kaynak-larünün de Ûerlendirilmesi. I.U. Orman Fak., Istanbul. OAUM Müd, Yayün No 1.
Altieri, M.A. 1991. How best can we use biodiversity in agroecosystems? Outlook on Agriculture, 20(1): 15-23.
Altman, A. et al. 1996. Molecular biology of drought tolerance and transformation of Populus and Pinus. Dendrome, 3(2): 5-7.
Bergschmidt, H. 1996. Plant genetic diversity in Germany - A resource for agriculture and forestry. Bonn, German Federal Ministry for Food, Agriculture and Forestry (BML). 67 pp.
Bonner, F.T. 1990. Storage of seeds: potential and limitations for germplasm conservation. Forest Ecology and Management, 35(1 -2): 35-43.
Boydak, M., Tunçtaner, K, Akalp, T. et al. 1997. Selection and biotechnological improvement of poplar clones for paper industry. Paper presented at the Eleventh World Forestry Congress, 13-22 October 1997, Antalya, Turkey.
Cheliak, W.M. 1993. Clone identification. In M.R. Ahuja & W.J. Libby. eds. Clonal forestry I. Generics and biotechnology, p. 101-109. Berlin, Springer-Verlag.
Commandeur, P. et al. 1996. Public debate and regulation of biotechnology in Europe. Biotechnology and Development Monitor, 26: 2-8.
Drewery, L. 1994. Keeping faith with the future: forests and their genetic resources. Rome, CGIAR and IPGRI. 13 pp.
Ehrlich, P.R. 1990. Habitats in crisis: Why we should care about the loss of species. Forest Ecology and Management, 35(1 2): 5- 11.
Eldridge, K. G. 1990. Conservation of forest genetic resources with particular reference to Eucalyptus species. Commonw. For. Rev., 69(1): 45-53.
Falk, D.A. 1990. Endangered forest resources in the US. Integrated strategies for conservation of rare species and genetic diversity. Forest Ecology and Management, 35(1-2): 91-107.
FAO. 1993. Conservation of genetic resources in tropical forest management - principles and concepts. FAO Forestry Paper No. 107. Rome.
FAO. 1996. Management guidelines for in situ gene conservation of wind-pollinated temperate conifers. By V. Koski. Forest Genetic Resources, 24: 2-7.
Haines , RJ. 1993. Biotechnology and the genetic improvement of forest trees. Biotechnology and Development Monitor, 15: 3-5.
Howard, J.L. 1997. An estimation of opportunity cost for sustainable ecosystems. Paper presented at the Eleventh World Forestry Congress, 13-22 October 1997, Antalya, Turkey.
Huang, Y., Karnosky, D.F. & Tauer, C.G. 1993. Applications of biotechnology and molecular genetics to tree improvement J. Arboriculture, 19(2): 84-98.
IPGRI. 1993. Diversity for development. The strategy of the International Plant Genetic Resources Institute. Rome. 62 pp.
Irenmonger, S. et al., 1997. A global overview of forest conservation. Paper presented at the Eleventh World Forestry Congress. 1322 October 1997, Antalya, Turkey.
Isik, K. 1996. Biyolojik çestlilik ve orman gen kaynaklarümüz (Biological diversity and our forest genetic resources) (Collection of author's various articles). Ministry of Forestry Publication No. 13. Ankara. 120 pp. (In Turkish)
Isik, K. 1997. Biyolojik çesitlilik (Biodiversity). Bilim ve Teknik (Science and Technology). Ankara, Scientific and Technical Research Council of Turkey 30(350): 84-87.
Isik, K., Kaya, Z. & Atalay, I. 1995. Biodiversity action plan for Turkey. I. Forest ecosystems. Draft report submitted to General Directorate of National Parks and Wildlife. Turkish Ministry of Forestry (in Turkish); and to World Bank, Ankara (in English). Ankara. 110 pp.
Karaca, H. 1997. Biodiversity in forest ecosystems in Turkey. Status and recommendations. Paper presented at the Eleventh World Forestry Congress, 13-22 October 1997, Antalya. Turkey.
Kaufmann, M.R. et al. 1994. An ecological basis for ecosystem management. General Tech. Report RM-246. Fort Collins, Co., USA, USDA Forest Service.
Kaya, Z. & Neale, D.B. 1993. Randomly amplified DNA (RAPD) polymorphisms in Pinus nigra var. pallasiana and Pinus brutia. Doûa, Turkish J. Agriculture and Forestry, 17: 295-306.
Khan, M.H. 1997. Conservation of Biodiversity and endangered ecosystems in Pakistan. Paper presented at the Eleventh World Forestry Congress, ] 322 October 1997, Antalya, Turkey.
Krishna, N. & Shankar, V.B. 1997. Conserving the ecological heritage Sacred groves in Tamil Nadu. Paper presented at the Eleventh World Forestry Congress, 1322 October 1997, Antalya, Turkey.
Kun, E., Kaya, Z. & Güner, A. 1996. National plan for in situ conservation of plant genetic diversity in Turkey. Draft report. Supported by Ministry of Environment, Ministry of Agriculture and Rural Affairs and Ministry of Forestry. Ancara. 116 pp.
Lammerts van Bueren, E.M. & Duivenvoorden, J.F. 1997. Towards priorities of Biodiversity research in support of policy and management of tropical rain forests. Paper presented at the Eleventh World Forestry Congress, 13-22 October 1997, Antalya, Turkey.
Ledig, F.T. 1986. Conservation strategies for forest gene resources. Forest Ecology and Management, 14: 77-90.
Libby, W.J. 1990. Genetic conservation of radiate pine and coast redwood. Forest Ecology and Management, 35(1 -2): 109120.
Mátyás, C. 1997. Conservation of genetic resources in a changing world Strategy considerations for temperate forest tree species. Paper presented at the Eleventh World Forestry Congress, 13-22 October 1997, Antalya, Turkey.
Millar, C.I. 1993. Conservation of germplasm in forest trees. In M.R. Ahuja &: W.J. Libby, eds. Clonal forestry. II. Conservation and application, p. 42-65. Berlin, Germany, Springer-Verlag.
Namkoong, G. 1991. Maintaining genetic diversity in breeding for resistance in forest trees. Annual Rev. Phytopatholgy, 29: 325342.
Ouédraogo, A.S. 1997. Conservation and use of forest genetic resources. Special paper presented at the Eleventh World Forestry Congress, 13-22 October 1997, Antalya, Turkey.
Peters, R.L. 1990. Effect of global warming on forests. Forest Ecology and Management, 35(1-2): 13-33.
Rodgers, W A. 1997. Patterns of loss of forest biodiversity - A global perspective. Special paper presented at the Eleventh World Forestry Congress, 13-22 October 1997, Antalya, Turkey.
SAF. 1992. Biological diversity in forest ecosystems: a position of the Society of American Foresters. J. Forest., 90(2): 4243.
Schnider, S.H. 1989. The greenhouse effect: science and policy. Science, 243: 771-781.
Sederoff, R.R. & Stomp, A.M. 1993. DNA transfer in conifers. In M.R. Ahuja & W.J. Libby, eds. Clonal forestry. I. Genetics and biotechnology, p.241 -254. Berlin, Germany, Springer-Verlag.
Sexton, W.T., Johnson, N.C. & Szaro, R.C. 1997. The ecological stewardship project. Paper presented at the Eleventh World Forestry Congress, 13-22 October 1997, Antalya, Turkey.
Simpson, J.A. & Ades, P.K. 1990. Screening Pinus radiata families and clones for disease and pest insect resistance. Australian Forestry, 53(3): 194-199.
Tabel, U. 1995. Forest production systems and their genetic diversity. In J.M.M. Engels, ed. In situ conservation and sustainable use of plant genetic resources for food and agriculture in developing countries. Report of a DSE/ATSAF/IPGRI Workshop, 2-4 May 1995, Bonn-Rövttgen, Germany.
Vitousek, P.M. et al. 1987. Biological invasion by Myrica faya alters ecosystem development in Hawai. Science, 238: 802-804.
Watt, M P., Blakeway, F.C., Hernan, B. & Denison, N. 1997. Developments in the use of biotechnology in commercial forestry tree improvement programmes in South Africa. Paper presented at the Eleventh World Forestry Congress, 13-22 October 1997, Antalya, Turkey.
WRI/IUCN/UNEP. 1992. Global biodiversity strategy. Guidelines for action to save, study, and use earth's biotic wealth sustainably and equitably. (In collaboration with FAO and UNESCO) Washington, DC. 244 pp.
WRI/UNEP/IUCN. 1995. National biodiversity planning. Guidelines based on early experiences around the world. WRI Publication, Baltimore, MD, USA. 161 pp.
Wrubel, R.P., Krimsky, S. & Wetzler, R.E. 1992. Field testing transgenic plants. An analysis of the US Department of Agriculture's environmental assessments. BioScience, 42(4): 280-289.
Yaltirik, F. 1972. The floristic composition of major forests in Turkey. International symposium on Trojan fir and Turkish flora. I.U. Orman Fak. (Forestry Faculty) Publication No. 209, p. 179-194.
Ziehe, M. & Hattemer, H.H. 1987. Populationsgenetische Ansätze zur Resistenz gegenüber Umweltschäden (Population genetic approaches to pollution resistance). Allgemeine Forst- und Jagdzeitung, 158(1112): 217-222.
Zobel, B. & Talbert, J. 1984. Applied forest tree improvement. New York, John Wiley and Sons. 505 pp.
Zuomin, S., Ruimei, C. & Youxu, J. 1987. Study on method for regional ecosystem biodiversity assessment. Paper presented at the Eleventh World Forestry Congress, 1322 October 1997, Antalya, Turkey.