Conservation of natural forest ecosystems is the main function of most protected forest areas and the term "protected area" encompasses a vast variety of approaches for the management of natural and semi-natural forest types. Protected forest areas currently cover only 5% of the tropical forest area and the rate of growth in protected forest areas has declined in recent years due to increased land use pressure. However, national parks and forest reserves are no longer the only method that can be used for the conservation of biological diversity. A possible alternative is multiple use forest management, which incorporates harvesting of forest products within a framework of sustainable management that aims at both conserving biodiversity and supplying benefits to local people and the national economy.
Although protected areas have been established that enjoy strict legal status, numerous problems arise in tropical zones in relation to their management. Problems include conflicts with local people over land rights and illegal extraction of animal and plant resources to mention just a few examples. These problems are often intensified due to the inability of state authorities to protect such areas. Hence, stated conservation achievements do not always reflect reality. In practice, even though there are good examples of effective national parks and forest reserves, the past hundred years or more have witnessed a parallel increase in both the number and surface area of protected areas and a growing number of extinct or threatened species. In effect:
_ The equation "protected areas = ecological diversity" is not necessarily true. The location of conservation areas is problematic, because information is lacking about the presence of plant and animal species in different types of forest stand. Up to now, plans for the designation of protected areas have been based on three main criteria: biogeographical divisions between the main ecosystems in a country; the degree to which resources are threatened or degraded; and high rates of diversity or species endemism. The representativeness of protected area systems is seriously restricted both by a lack of information about the way species are distributed and pressures from other types of land development. Furthermore, protected areas do not always ensure that biodiversity will be protected because they often cover limited surface areas and are divided up randomly.
_ The equation "forest classification type = level of conservation" is not automatic. Management practices in any particular area of forest are not always equivalent to the status that is supposedly given by its classification. For example, a complete natural reserve (i.e. a complete ban on human activity in the area) represents the maximum level of conservation that can be awarded, but this type of management can actually lead to less conservation than expected. To put this another way, the classification of a forest area does not guarantee protection if financial and human resources and political will do not support such a classification. In particular, in some countries, natural resource conservation is not considered a priority and short-term objectives are generally considered to be more important. Therefore, biodiversity needs to be understood more accurately from an economic and socio-cultural point of view. It should be given real value by integrating it into all economic decisions, in order to reconcile economic development and conservation interests.
Experience has shown that legal protection alone is not enough to ensure effective conservation activity. In particular, protected areas will only fulfil their conservation goals if the land around them is managed appropriately. In reality, many protected areas suffer from encroachment by farming and cropping activities. Currently therefore, the objective of biodiversity conservation in forests can only generally be ensured by the creation of substantial areas of natural forest for production around them. Such a "buffer zone" can support the protected area while, at the same time, provide local people with benefits.
Buffer zones are meant to form a physical barrier against human encroachment of the centrally protected area that also extends the natural habitat area of the protected area to beyond its legal boundary. Furthermore, the support of local people in conservation objectives can be promoted by their participation in the harvesting and management of buffer zones (e.g. through the use of appropriate agroforestry practices; hunting; establishing forest and agricultural tree plantations; and other activities). However, one drawback of buffer zones is that the economic development they generate can attract people to them and increase pressure on resources.
Management of forests for multiple outputs is more compatible with the goal of biodiversity conservation than management for wood production, but forests managed for wood production can also have a role to play. The notion of "extractive reserves" is one approach to conservation in production forests that allows local people, who depend on the forest for their livelihood, to harvest products (e.g. timber, non-wood forest products, game, etc.) at a low intensity.
Africa, which contains some of the most well known wildlife resources, is symbolic of the problems encountered in sustainable wildlife management. Wildlife habitats are being reduced and degraded by agriculture, livestock rearing and the overharvesting of forest resources. In addition, wildlife poaching is the source of extinction or near extinction of many wild animal species. Indeed, habitat degradation and excessive game hunting are the two main threats to fauna sustainability.
However, wildlife is also being used for tourism (e.g. hunting and ecotourism), mainly in Africa. Besides the financial value of these activities, this method of utilising wildlife resources should be ecologically and socially viable, but it is important to remember that wildlife also has considerable socio-cultural importance (e.g. religious and mystical significance).
In the past, authoritarian management of wildlife resources (i.e. the complete protection of wildlife) often failed. Measures taken to protect wildlife in such a way have harmed local communities and defied traditional cultural values. Total bans on the use and marketing of game have also forced communities to poaching.
Given the "res nulius" legal status of game, local people, when they are marginalised from wildlife management, consider wildlife as a free resource with open access. Although the state is generally the only body responsible for these resources, it is often unable to assume its management role. The implication of all this is that it is not generally possible to manage natural resources and fauna sustainably without the active participation of local communities in decision-making and subsequent benefits. Integrated community programmes for resource conservation have been formulated with success in several African countries, especially in the south (e.g. Botswana, Zimbabwe and Zambia), leading to a considerable drop in poaching, an increase in animal populations and to habitat regeneration.
Today the notion of biodiversity development and sustainable use is generally to be preferred to the idea of a total ban on the trading and marketing of wildlife and related products. As part of this, it is important to consider the potential multiple-uses that wildlife can provide, such as: recreation; food; and scientific, cultural, economic and ecological functions.
Although fire is a natural component of many forest ecosystems, it can damage vegetation and consequently lead to soil erosion and a loss of fertility if not used properly. Likewise, fires may also have harmful effects in that they can lead to carbon emissions during combustion. It has been proven that most forest fires are caused by human intervention due to a number of different causes, including: deliberate deforestation (i.e. forest conversion), slash and burn cultivation; rangeland regeneration (for grazing and hunting); accidents; traditional use (e.g. religious and tribal ceremonies); and political and socio-economic conflicts over land use and ownership rights (e.g. land use conflicts, conflicting land claims, arguments over debts, etc).
Fire is used as a tool to open up vast wooded areas for agriculture. Statistics indicate that more than 15 million ha of wooded areas are burnt each year for this purpose. However, if used properly and with care, fire is a valuable tool for farmers and herders. In forestry, for example, it is used in the preparation of sites for establishing plantations or to encourage natural regeneration. Nearly 500 million people practise shifting cultivation using fire over an area of 300 million ha to 500 million ha each year. Increases in the size of cleared areas and a shortening of crop rotation cycles is leading to increased resource degradation.
Even in humid zones, forest fires are occasionally the main cause of deforestation (e.g. in 1997), particularly in the Brazilian Amazon and in Indonesia. Drought, combined with the "El Niño" phenomenon, has resulted in forest fires of serious dimensions in several recent years. At the beginning of the 1980s, exceptional periods of drought, coupled with the Harmattan, led to the outbreak of numerous fires in Africa from Guinea to the Central African Republic. Forest fires can cause considerable tree mortality and forest destruction if repeated and then bare soils, that are subsequently covered in easily inflammable weeds (e.g. Imperata and Chromolaena odorata), are very difficult to regenerate naturally.
Forest fires in sub-humid and humid African areas can be the most important obstacles to the sustainable management and conservation of forest resources. More recently in 1998, in Central America, the Caribbean and in Brazil, many forest areas were damaged by fire.
From the 1970's onwards, trials of various mechanical means of controlling brush fires were carried out using modern apparatus (e.g. fire trucks, pumps, etc.). The high cost of these methods of fire control led to the promotion of greater participation of local communities, education and training, and the use of small equipment and manual tools in fighting forest fires. However, deliberate and controlled burning at the beginning of the dry season is by far the safest and most effective fire protection method in most cases.
In reality, problems of fire control are more sociological in nature than technical. Effective fire control is more a matter of popular education and agricultural policy than direct control and response.
In tropical regions, most watersheds contain a large farming population. Particular agricultural arrangements, like terraced farming in Asia, present tried and tested soil and water conservation functions. On the other hand, reforestation in areas degraded by farming and grazing has turned out to be an expensive technical solution. In consultation with local people, improved forest protection will often lead to natural regeneration and enable secondary forest to be restored in many instances.
In natural forests that are managed for logging and which are located on steep slopes, the effects of these activities on watersheds will depend mainly on the layout of roads and skid trails and the quality of their maintenance. Other important factors are the felling and skidding techniques used, silvicultural treatments, protection against fire and pests, and other forestry activities.
Forested watersheds that provide water to densely populated areas should be protected against shifting cultivation and unplanned urbanisation. The only "management" in such cases should be effective surveillance to protect forest cover. Associating the functions of water supply and natural reserves for wildlife and plant life in the same watershed (examples of this occur in national parks in Kenya and Tanzania) does not generally present any technical problems and water management carried out downstream from these areas can be successful.