Basic elements of sustainable forest management
Robin aus der Beek
Proyecto Silvicultura de Bosques Naturales
7170 Turrialba, Costa Rica
CATIE's basic principles for ecologically sustainable, economically interesting, technically feasible and socially equitable silviculture and management of tropical humid forests are summarized. Management on the basis of the planning of objectives and production, regulation of the timber harvested, training of forest workers, directed felling and integral harvesting, implementation of post-harvest activities and silvicultural treatments, maintaining or increasing the value of future yields, is recommended.
Although it is quite difficult to have the exact estimation about the actually remaining forest cover in Central America, this should be around 18 million hectares, covering 36% of the total area (Pedroni and Flores, 1992). On the other side, a deforestation rate of about 354 thousand hectares each year, mainly in humid tropical forest, shows that there is still no adequate use of the multiple forest functions. At all levels a worrisome ignorance is apparent concerning the opportunities offered by natural forest management for socioeconomic development and for maintenance of equilibrated environment. Since the arrival of the Spanish, when nearly the whole Central American territory was covered by forests, until today, more than 70% of natural forest have disappeared in the Region.
The main causes of deforestation can be summarize as follows (de Camino, 1993; Sabogal et al., 1993):
· Land use for migratory agriculture, and subsistence agriculture.
· Cattle raising.
· Forest harvesting activities.
· Road construction in forest zones.
· Export agriculture.
· Firewood production and urbanization.
· Strongly detailed forest legislation.
· Land possession.
· Low price for timber products.
· Missing information about ecological sustainable and economical interesting forest management.
· Limited acceptance of forest species on the wood markets.
· Limited number of well-trained forest professionals.
· New causes of deforestation, like the end of the wars, land reform and increased needs of exportation, caused by political structural adjustment.
On the other hand, although the diagnosis of the deforestation problem shows that the situation hardly could change in short term, during the last 5-10 years many positives advances concerning sustainable forest management have been done, so that actually many useful experiences are available for demonstration and dissemination. These efforts constitute an opportunity for international cooperation and demonstrate an increasing conscience as well as a real will to adopt sustainable practices for the use of forestry resources.
The most important advances in that sense, surely have been carried out by CATIE1 (Tropical Agricultural Center for Research and Education), whose strategic objective for the 1990s is the development of ecologically sustainable, economically viable and socially and culturally acceptable management techniques for the major natural and plantation forest resources of Tropical America. In its research work, concentrated in finding solutions to today problems in the most urgent areas, CATIE gives particular emphasis to growth, yield and natural regeneration of forests under different intensities of intervention, and the costs and benefits on management-related work; the effects of intervention in natural forests on plant biodiversity; silviculture of multipurpose trees; genetic improvement and germplasm conservation; ethnobotanical studies, and the economics of conservation.
1 CATIE is a civil, non-profit, autonomous association, scientific and educational in nature. It carries out, promotes and stimulates research, education, training, and technical cooperation in agriculture and management of natural resources to the benefit the people of the American tropics, particularly in the countries of the Central American Isthmus and the Antilles. The Center was created in 1973. Founding members were the Interamerican Institute for Agricultural Cooperation (IICA) and the Government of Costa Rica. Panama joined in 1975, Nicaragua in 1978, Honduras and Guatemala in 1979, Dominican Republic in 1983, El Salvador in 1987, and Mexico and Venezuela in 1992.
Presently three projects are forming the Natural Forest Management Unit (UMBN) in CATIE:
· Silviculture of Natural Tropical Forest, financed by the Swiss Development Cooperation and Overseas Development Agency. This is a research project working in high mountain oak-bamboo forests of Costa Rica, as well as in primary and secondary tropical rain forest in the lowlands of Costa Rica and Panama.
· Production in Natural Tropical Forest, financed by USAID. This is a research and training project, working in the tropical rain forests of Costa Rica, Guatemala, Honduras and Nicaragua.
· Conservation for Sustainable Development (OLAFO), financed by the Norwegian and Danish Development Agencies (NORAD and DANIDA). This project mainly works on non-timber forest products and integrated management of natural resources involving local communities in small-scale management operations, in Costa Rica, Guatemala, Honduras, Nicaragua and Panama.
This paper is intended to present CATIE's contribution in developing sustainable forest management techniques and show the main principles that CATIE considers should be respected therefore, based on its experiences carried out in the different countries of Central America.
Figure 1. Locations of CATIE's forest management demonstration areas in Central America.
In the following sections, the main forest management operations are presented, describing the basic principles that should be considered if ecological sustainability is to be guaranteed.
Forest experts commonly define sustainability in terms of wood-production, as it has been conceived since more than two centuries. Nevertheless, a new vision is becoming more and more popular, which expresses sustainability not only in terms of timber production, but also considering other forest values like biodiversity and main ecological functions.
One basic condition for forest management, is the conservation of the forest cover itself as well as the conservation of its capacity to satisfy all different kinds of exigency from the society. Besides that, also the long term, required for forest production, and the strong pressure of other sectors on the forests, make a careful short and long term planning indispensable, which must be integrated in a regional land use plan. In addition to the planning, a constant control of its realization and a respective adjustment to the changing conditions are essential.
The result of the planning must be summarized in the forest management plan, which has to serve to the forest owner and the government as instrument for conduct, control and evaluation, covering technical, economical, silvicultural and social aspects related to the management.
Planning activities should be divided in two main stages:
1. Long-term planning. During this first stage, the forest areas that have to be managed, must be exactly defined and classified according to the goals of their management (protection, production, public recreation, etc.). Considering the high complexity of social interests towards the forest, at this stage of the planning, it's very important to involve actively each interested sector related with forest management, in order to satisfy their exigency as well as possible, and therefore later on avoid all sort of conflicts.
Once the main function(s) of each forest area is defined, it's also important to analyze the potential of the forest itself to fulfill it, and give some general indications about the measures that have to be taken.
2. Short-term planning. Considering the guidelines given by the long term planning, the short time planning has to be carried out, detailing the specific activities that have to be realized each year in specific forest area.
In case of forest management for timber production, these annual activities must be described in Annual Operating Plans, specifying aspects like:
· Road construction
· Pre-harvest activities
· Training activities
· Logging intensity
· Harvest products
· Criteria for selection of the trees that have to be harvested
· Planning of all harvest activities (felling, extraction, landing, transport, etc.)
· Activities carried out by local communities (firewood production, charcoal production, post production, harvesting of non-timber products, etc.)
· Planning of post-harvest activities (silvicultural treatments, forest diagnostics, road maintenance, and similar activities)
For those forests, where the main function is wood-production, a good planning must include, at least, the execution of one census of commercial timber, in order to obtain information concerning the existing timber volumes, the location of commercial timber, as well as some information about the topographic conditions, possible extraction methods, landing operations, etc. This information must be resumed on maps, figures and tables, in order to make it more accessible for their users. When carrying out the census, it is recommended to cut all sort of tree-climbers, on trees that are supposed to be felled, in order to reduce the damages of logging activities.
CATIE's experience indicates that approximately 4-5 ha can be inventoried in one day, with a respective cost of 18-25 US$/ha, depending on the salaries of the different countries (Sabogal et al., 1993).
Though the importance and utility of forest management plans, in most tropical countries it is still not seen as a useful and indispensable instrument for sustainable forest management. In most cases it is considered as a bureaucratic step, that has to be taken in order to obtain cutting permission. The traditional plans are therefore very big documents containing a lot of useless information presented in form of graphics or tables, not corresponding at all to what a management instrument should be. This is why CATIE and the Tropical Forest Action Plan for Central America (PAF-CA) have been entrusted with preparing a proposal for a simplified forest management plan.
One of CATIE's main products concerning forest management planning, is therefore the "Model for Simplification of Forest Management Plans, for Tropical Rain Forests in Central America"2, which has been published in 1994, and is supposed to be adopted in all Central American countries.
2 PAF-CA, CATIE/USAID, WWF. 1994. Modelo de Simplificación de Planes de Manejo para Bosques Naturales Latifoliados en la Región Centroamericana. 65 pp.
The conservation of a productive forest ecosystem, is possible only if careful logging technologies are applied, in order to reduce to a minimum, the damages caused to the remaining vegetation, to natural regeneration as well as to the soil. In this sense, one very important aspect of careful logging, is the correct planning and construction of forest roads and skidder trails.
Traditionally, no road or skidder trail planning has been carried out and the heavy machines simply opened their way through the forest towards the tree that had to be felled, destroying the vegetation, and especially the natural regeneration, in all directions. This is why one of CATIE's important demonstration objects in forest management, is the way how roads must be planned and constructed, giving indications about road density and their construction details, according to the kind of forest as well as to the social and the given topographic conditions. For economical as well as for ecological reasons, the road and skidder trail construction density must be maintained as low as possible and avoid crossing streams or other fragile sites. Generally two kind of roads are necessary for the timber extraction: a mostly permanent main forest road giving access to the managed area during the whole year (including the rainy season), and a series of skidder trails, normally not permanent, which provide access to individual trees that will be extracted from the forest.
Due to the different conditions in each kind of forest, it's not possible to give exact indications about how road and skidder trails should be constructed. In the high mountain oak-bamboo forests, for example, the slow dynamics of the ecosystem and the high density of commercial timber (573-713 m3/ha), allow the building of permanent infrastructure, while this may not be the right thing in the tropical rain forests of the lowlands, because of the intensive maintenance work that should be done, and because of the long distance between the trees that are supposed to be felled by each intervention.
One of the most important basic aspects of sustainable forest management, surely is the careful application of the right felling methods, that allow to define the right felling direction of the trees, as well as to succeed felling the trees in the established direction. Although importance, it is very difficult to find well qualified forest workers in Central America, trained in directional felling and other activities related to it. In most cases, felling activities are carried out by local farmers with none or very little experience in using saws, and besides that, no measures for human protection are applied.
In order to fill this gap, CATIE started a training program for forest workers, including aspects like silviculture, road and skidder trail planning and construction, directed felling methods, first aid and upkeep of material. After one year of theoretical and practical training, the workers succeeded very well their exams, and actually surely belong to the most qualified forest workers in Central America. As a result of this training, the realized harvesting activities, caused the lowest damage intensity ever registered in the tropics. Due to the success of this training course, it is supposed to be carried out on bigger scale during the next years, as part of the activities of a new CATIE training Project, starting 1995.
Following on with the basic aspects of sustainable forest management, an other essential side surely is the careful and integral extraction of the timber products. CATIE's innovative recommendation on this aspect, is the use of cables for the log extraction, which permits the machinery to extract the logs without leaving the skidder trails or the forest road, and therefore reduce considerably the damages to the forest, specially to the natural regeneration and to the soil. That is why the roads and skidder trails have to be planned so that every felled tree can be reached by the machinery with a 40 m long cable (without leaving the infrastructure). Besides that, it is also recommended to undertake all extraction activities during the dry season, avoiding using the skidder trails in rainy season.
Also important, in order to reduce the damages, is a integral use of the felled trees. Especially because of the limited number of species and products harvested in the forest, the economical profitability per hectare forest is not competitive enough with other land uses. If the adoption of ecologically sustainable and economically competitive forest management is attempted, it is indispensable to increase the forest production, by finding a more integral use of felled trees and caused damages.
Traditionally, only the best part of the logs are extracted, while tree branches and many other products are wasted. The integral exploitation of the felled trees, not only has advantages from the economical point of view (more incomes are generated), but also in ecological and the social terms as well.
While the felling activities only should be realized by well trained forest workers, other operations like firewood production, charcoal production, posts production, etc. are a great opportunity to involve local farmers in sustainable forest management, doing activities they traditionally have been realizing. This way, the forest can become an important source of incomes for local communities, increasing their interest in conserving the forest itself.
CATIE's experience in the high mountain oak-bamboo forest, showed for example that by harvesting approximately 70m3/ha a production of nearly 350 m3 of firewood and hundreds of posts is possible by using the branches (Stadtmüller and aus der Beek, 1991).
On the other hand, if all branches of felled trees are used for firewood or other production before starting with the log extraction, the area gets free from obstacles that increase the difficulty of log extraction and therefore increase the costs of this operation and the damages caused to the remaining stand.
In both cases, silvicultural interventions and timber production, often logs are produced with very good quality but insufficient dimensions. If these logs are used for firewood production, quality wood may be wasted, but on the other hand, because of the dimensions, they are not accepted in the sawmill industries. One right thing to do in that case, can be the manual sawing in the forest, with a portable sawmill.
According to CATIE's experience, if all the mentioned activities could be included in forest management practices, considerable social, ecological and economical advantages may be attained.
Although they are often not considered in forest management planning, there are many activities that should be carried out after harvesting, whose ecological and economical benefits are unfortunately underestimated. Among these activities the road maintenance, silvicultural treatments, control of established permanent plots, should be mentioned.
As of particular importance for sustainable tropical rain forest management, CATIE started promoting the "Sampling Diagnosis", consisting of a simple and practical technique to obtain essential information about the conditions of the remaining forest and particularity about its natural regeneration. In 10 m x 10 m plots the best tree of commercial species is selected and classified according to its conditions of illumination, crown form and stem quality. Based on this information, the timber productivity of the forest can be estimated and silvicultural treatments can be defined.
Another important, but also very questionable activity of sustainable tropical forest management, is the silvicultural treatment that should be defined and applied once harvesting is finished. The major problem concerning such treatments is that they often don't generate immediate revenue.
The improvement of the traditional forest operations must include: a good long- and short time planning previous to harvesting; the education and training of involved personal, technical supervision of the execution of the different harvest-operations (inventory, road construction, felling and extraction activities, landing, etc.), as well as ex-post evaluation, considering not only timber products, but also ecological values and the future forest conditions.
Although high deforestation rates continue in Central America, many positive advances have been made during the last 10 years showing that humid tropical forest management is possible with ecological, economical and social benefits, if certain basic principles are respected. However the adoption of sustainable forest management practices mainly depends on political will at the national and international scales. That's why CATIE is trying to underline the role of humid tropical forest in the sustainable development of Central America, by undertaking research and training activities in most countries of the Region, involving every concerned actor (especially political authority), in order to revert the current situation.
De Camino, R. 1993. El papel del bosque húmedo tropical en el desarrollo sostenible de América Central: desafíos y posibles soluciones. Revista Forestal Centroamericana 6:7-16.
Finegan, B., Sabogal, C., Reiche, C., and Hutchinson, I. 1993. Los bosques húmedos tropicales de América Central: su manejo sostenible es posible y rentable. Revista Forestal Centroamericana. 6:17-27.
Pedroni, L. 1991. Conservación y producción forestal: aspectos para su conciliación en el marco de un manejo sostenible. El Chasqui (C.R.) 27:7-22.
Pedroni, L., and Flores R., J. 1992. Diagnóstico forestal regional para Centro América y propuestas de trabajo. Informe de INTERCOOPERATION y UICN/ORCA.
Author's Contact Information
Robin aus der Beek
Proyecto Silvicultura de Bosques Naturales
Telephone: (506) 556.04.01
Fax: (506) 556.15.33