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BOIS ET FORÊTS DES TROPIQUES, 2002, N° 272 (2)
33
GESTION FORESTIÈRE / LE POINT SUR…
Environmentally-friendly
forestry systems
in Central America
This paper presents
examples of sustainable forest
management research by CATIE
(Tropical Agriculture Research and
Higher Education Center). Studies
cover timber harvesting practices as
well as research on uses of non-
timber forest products and valuation
of environmental services provided
by forests. In addition, they consider
strategies for the restoration of
degraded ecosystems, including
reforestation with native species.
The studies described are part of
larger programs to design
techniques for sustainable forest
management throughout the Central
American region.
Florencia Montagnini
José Joaquín Campos
Jonathan Cornelius
Bryan Finegan
Manuel Guariguata
Daniel Marmillod
Francisco Mesén
Luis Ugalde
Area of Management and
Conservation of Forests and
Biodiversity, Tropical Agricultural
Research and Higher Education
Center (CATIE)
7170 Turrialba
Costa Rica
The forest at La Selva Biological Station,
in Costa Rica, is protected from hunting
and connected to a national park. Seed
dispersal by mammals and seedling
survival were higher than at Tirimbina
(a nearby, unprotected forest).
La forêt entourant la station biologique
de La Selva, au Costa Rica, est interdite à
la chasse et jouxte un parc national. La
dispersion des semences par les mammifères et le taux de réussite des jeunes
plants y sont plus élevés qu’à Tirimbina (une forêt proche, non protégée).
Photo F. Montagnini.
BOIS ET FORÊTS DES TROPIQUES, 2002, N° 272 (2)
34
FOCUS / FORESTRY SYSTEMS
RÉSUMÉ ABSTRACT RESUMEN
GESTION FORESTIÈRE RESPECTUEUSE ENVIRONMENTALLY-FRIENDLY FORESTRY MANEJO DE BOSQUES TROPICALES
DE L’ENVIRONNEMENT EN AMÉRIQUE SYSTEMS IN CENTRAL AMERICA FAVORABLE PARA EL AMBIENTE EN
CENTRALE AMÉRICA CENTRAL
Sustainable logging practices can result in
Comparées aux techniques classiques, les higher seedling regeneration, and higher Los bosques cosechados utilizando prácti-
techniques d’exploitation forestière à understory biodiversity than in forests cas sostenibles pueden tener mayor rege-
faible impact favorisent la régénération logged by conventional methods. Post- neración arbórea, y mayor biodiversidad
des arbres et la biodiversité du sous-bois. harvest silvicultural treatments increase en el sotobosque, que bosques cortados
Les traitements sylvicoles post-récolte the diameter growth of crop trees, utilizando métodos convencionales. Los
augmentent le diamètre des arbres ; il although the consequences of their effects tratamientos silviculturales post-cosecha
reste à évaluer l’effet de ces traitements on forest composition need to be aumentan el crecimiento diamétrico de
sur la composition floristique de la forêt. assessed. Management operations affect árboles deseables, aunque las consecuen-
En général, les opérations sylvicoles modi- plant diversity in different ways, over dif- cias sobre la composición del bosque
fient la diversité floristique. Cependant, ferent time scales, but there is no evi- deben aún ser evaluadas. Las operaciones
avant la première coupe, il n’apparaît pas dence of drastic changes in diversity dur- de manejo afectan la diversidad de dife-
de changement important de la composi- ing the first felling cycle, even in stands rentes maneras, pero no existe evidencia
tion, y compris dans les peuplements dont whose structure is altered by refine- de cambios drásticos en la diversidad
la structure est modifiée par les traite- ment/liberation treatments. Seed disper- durante el primer ciclo de corta, aun en
ments d’éclaircie. La dispersion et la ger- sal and germination can also be affected rodales alterados por tratamientos de refi-
mination des semences évoluent suite à la as a result of loss of fauna and changes in namiento/liberación. La dispersión de
diminution de la faune et au changement the forest microenvironment. In addition semillas y la germinación también pueden
des conditions micro-environnementales. to research on technologies for sustain- ser afectadas por la defaunación y cam-
Outre des recherches sur les techniques able management of tropical forests and bios en el microambiente. Además de la
de gestion durable des forêts tropicales et their biodiversity, CATIE is also involved in investigación en tecnologías para el mane-
de leur biodiversité, le Catie participe à la designing systems for diversified forest jo sostenible de bosques tropicales y su
mise en place de systèmes de gestion management, which includes studies on biodiversidad, el CATIE también esta dise-
forestière diversifiée et il réalise des the ecology and management of non-tim- ñando sistemas de manejo diversificado
études sur l’écologie et la sylviculture ber forest species. Many forest manage- del bosque, incluyendo estudios de ecolo-
d’espèces ligneuses non productrices de ment practices are best suited to small gía y manejo de especies no maderables.
bois d’œuvre. De nombreuses pratiques farmers, farmer cooperatives, or commu- Muchas prácticas de manejo de bosques
de gestion forestière sont très bien adap- nity forest users. Some farmers’coopera- son más adecuadas para pequeños agri-
tées aux petits agriculteurs, aux coopéra- tives in Costa Rica manage forests for eco- cultores, cooperativas o bosques comuna-
tives et aux communautés forestières. Au tourism and non-timber forest products, les. Algunas cooperativas de agricultores
Costa Rica, des coopératives gèrent leur and also cultivate other portions of their en Costa Rica manejan los bosques para el
forêt pour l’écotourisme et les produits land as well as reforesting degraded land eco-turismo y productos no maderables,
non ligneux, elles pratiquent l’agriculture with native or exotic species, often as cultivan otras porciones de sus tierras y
sur d’autres portions de terre et reboisent mixed-species planting schemes. Tropical reforestan tierras degradadas con espe-
les terres dégradées avec des espèces plantations can supply wood products, cies nativas o exóticas, a menudo en plan-
locales souvent plantées en mélange. Tout contribute to carbon sequestration and taciones mixtas. Las plantaciones tropica-
en fournissant des produits ligneux, les land reclamation, as well as accelerating les proveen productos maderables,
plantations tropicales contribuent à la natural regeneration. Domestication of contribuyen a la acumulación del carbono,
séquestration du carbone et à la restaura- promising species for plantations involves recuperación de tierras y aceleración de la
tion des terres dégradées. Elles favorisent selecting outstanding trees, evaluating regeneración natural. La domesticación de
également la régénération naturelle. La genetic variability, seed germination and especies promisorias para plantaciones
domestication d’espèces prometteuses storage, evaluating the performance of incluye selección de árboles sobresalien-
suppose de sélectionner des arbres remar- species under different silvicultural sys- tes, evaluación de variabilidad genética,
quables, d’évaluer la variabilité géné- tems, and developing seed orchards for germinación y almacenamiento de semi-
tique, de contrôler la germination et le the production of genetically improved llas, evaluación del comportamiento de
stockage des graines, d’évaluer le com- seeds. especies bajo diferentes sistemas silvicul-
portement de l’espèce selon des scéna- turales y desarrollo de huertos semilleros
rios sylvicoles et de développer des Keywords: biodiversity, diversified forest para la producción de semillas genética-
vergers à graines pour produire des management, genetic improvement, mente mejoradas.
semences génétiquement améliorées. mixed plantations, ecosystem restoration.
Palabras clave: biodiversidad, manejo
Mots-clés : biodiversité, gestion forestière diversificado de bosques, mejoramiento
diversifiée, amélioration génétique, planta- genético, plantaciones mixtas, restaura-
tion mixte, restauration des écosystèmes. ción de ecosistemas.
BOIS ET FORÊTS DES TROPIQUES, 2002, N° 272 (2)
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GESTION FORESTIÈRE / LE POINT SUR…
Introduction Long-term studies
on ecological and
Most current forest manage- financial suitability commercial species. Simulations using
ment schemes for the production of SIRENA, a growth and yield model (De
timber result in physical disruption of of natural forest Camino, 1997), suggested that sus-
the forest structure and its plant and management tainable management can be achieved
animal life. However, various prac- when harvesting is kept to moderate
tices can greatly diminish the impacts At CATIE, long-term research has levels, when post-harvesting treat-
of forest management on biodiversity. focused on developing technologies ments are applied to maintain an
Many tropical countries have recently for sustainable management of natu- appropriate composition of commer-
changed forest management regula- ral forests and their biodiversity. cial species, and when a cutting cycle
tions to make them compatible with Researchers have recently created of 20 years is selected.
the principles of sustainable yields models to predict and simulate Research and experience on sus-
and biodiversity preservation. growth and yields in primary and sec- tainable forest management at CATIE
Specific guidelines are needed to ondary forests. CATIE has generated go hand in hand with the development
cover a vast array of forest conditions the most complete body of quantita- and validation of criteria and indicators
at both large and small scales. These tive and qualitative information avail- of sustainable forest management,
guidelines should be adjusted to suit able on ecological and economic fea- and with the establishment of local
the scale and objectives of manage- sibility in the region. procedures for forest certification.
ment as well as the resource require- For example, a financial analysis CATIE´s leadership in Forest Certifi-
ments of the species involved. of sustainable management in a har- cation in Central America has been
To make systems more “environ- vested forest was recently conducted strengthened during the last couple of
mentally friendly”, silvicultural and at the Tirimbina Rain Forest Research years. CATIE personnel are also
management schemes have concen- Center, located in Costa Rica’s Atlantic involved in similar activities in the host
trated on decreasing forest damage zone. The Tirimbina forest is part of a country of Costa Rica (Comisión Nacio-
by lowering the intensity of timber network of key sites for long-term nal de Certificación Forestal, 1999).
harvests and by improving logging research on sustainable forest man-
practices (Bertault, Sist, 1997; Sist agement in tropical America. Based on
Farmers of Coope San Juan, an agricultural
et al., 1998). However, not much has studies on economic feasibility and
cooperative located in Aguas Zarcas, NE Costa Rica,
been done to standardize procedures impacts on plant biodiversity, it was
grow a medicinal plant, “raicilla” or “ipecacuana”
for the selection of remnant seed found that at least 30 hectares, and 10- (Cephaelis ipecacuana), in the natural forest
trees, or to avoid disruption of polli- 15 m3 per hectare should be harvested understory.
nators and seed dispersers. Additio- if management is to be economically Les fermiers de la Coope San Juan, une coopérative
nally, forest management schemes attractive (Campos et al., 1998). In agricole située à Aguas Zarcas, au nord-est du Costa
often function in isolation with these forests, post-harvesting treat- Rica, font pousser une plante médicinale appelée
respect to the rest of the landscape. ments increased growth, especially for raicilla ou ipecacuana (Cephaelis ipecacuana) dans
les sous-bois d’une forêt naturelle.
Photo F. Montagnini.
BOIS ET FORÊTS DES TROPIQUES, 2002, N° 272 (2)
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FOCUS / FORESTRY SYSTEMS
Effects of
silvicultural
intervention on tree
diameter
increments and
forest diversity
As part of CATIE’s ongoing
research on biophysical aspects of for-
est management, work is being con-
ducted on the effects of timber har-
vesting and silvicultural treatments on
stand productivity and dynamics, and
plant species diversity and composi- A young plantation of Vochysia guatemalensis, one of the native species used for
tion in a managed Pentaclethra-domi- reforestation of degraded agricultural land in Coope San Juan.
nated rain forest typical of Central Jeune plantation de Vochysia guatemalensis, une des essences indigènes utilisées
pour le reboisement des terres agricoles dégradées de la Coope San Juan.
America’s Atlantic coast. Timber was
Photo F. Montagnini.
harvested from the whole area under
strict planning and control in 1989 and
1990 (Finegan et al., 1999). The total
harvestable volume was 23 m3/ha but in 1996, even though there were small show net declines after silvicultural
actual harvest intensity was 42% of net declines in silviculturally treated treatment, because in a given plot, a
this (10.1 m 3 /ha). Three different plots in the first years after treatment, proportion of the individuals eliminat-
regimes of post-harvest silvicultural while control plots showed net ed are bound to be the only represen-
intervention were applied during 1991- increases. There were no statistically tatives of their species. The lack of
1992: control (timber harvest only), a significant effects of treatment on significant differences between the
treatment combining refinement (gen- diversity in the understory either. refinement/liberation treatment and
eral removal of weeds, defectives and There were, however, significant dif- the control plots in the Pentaclethra
other undesirable trees in the interests ferences in understory diversity at forest, however, indicates that varia-
of better utilization of the site by the small scales, in the habitat mosaic tion in species richness is affected by
desired crop) and liberation (freeing formed by timber harvesting: undis- many factors and that silvicultural
potential crop trees from competing turbed patches, canopy gaps and treatment like that applied, despite
overtopping and neighbouring trees); trails. the drastic modification of forest
and a shelterwood (thinning of the Many previous studies have structure it brings about, is not the
middle stories of the forest to create demonstrated forest structure recov- single most important factor.
conditions for the regeneration of ery and increased diameter incre- However, the felling and extraction of
more light-demanding commercial ments of potential crop trees follow- timber, which disturbs the understory
species) (Finegan, Camacho, 1999). ing liberation and refinement directly, showed marked, though
The three different regimes treatments in tropical forests, but few localised, effects on stem density and
brought about marked differences in have focused on changes in overall species richness in the understory.
stand structure, and diameter incre- plant diversity. The preliminary results The short-term effects of forest man-
ments of potential crop trees were of the study in the managed Pentacle- agement on plant diversity clearly
higher under the refinement-libera- thra forest show different forest depend on the size-class under con-
tion treatment than in the control dur- responses, in different size-classes, at sideration and the nature of the oper-
ing the 1993-1998 period (Finegan, different scales of space and time. It is ation, and full understanding of plant
Camacho, 1999). Abundances of char- important to understand the causes diversity changes in managed forests
acteristic tree species were reduced and nature of species loss from per- will probably only be achieved
by the refinement/liberation treat- manent sample plots in such studies, through the wider application of sam-
ment. Species richness/ha, equal or in order to identify the implications of pling protocols or experimental
superior to 10 cm diameter at breast these results in terms of the relation- designs which permit the individual
height (dbh), did not differ signifi- ship between silvicultural treatment assessment of each operation. Long-
cantly between silviculturally treated and tree species diversity. In species- term follow-up is clearly needed to
(mean 100/ha, s.d. 7.5, n=3) and con- rich forests, species richness equal or assess overall changes in forest diver-
trol plots (mean 111/ha, s.d. 6.2, n=3) superior to 10 cm dbh in 1.0 ha can sity.
BOIS ET FORÊTS DES TROPIQUES, 2002, N° 272 (2)
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GESTION FORESTIÈRE / LE POINT SUR…
Loss of fauna, seed Sustainable
dispersal and management of
seedling secondary forests
establishment in
logged forest with Throughout the lowland neotro-
pics, secondary forest ecosystems
different levels of are receiving increased attention as a
protection timber source. Particularly in Central
America, the area under secondary
forest is rapidly growing on aban-
At CATIE, the effects of loss of doned pasture lands (Kaimowitz,
Abundant woody and herbaceous
fauna on the dispersal, predation and vegetation growing under the
1996). Although a large body of eco-
survival of seeds and seedlings were canopy of a nine-year-old mixed logical information exists on second-
recently studied in two selectively- plantation of native species at La ary forest succession, few forestry-
logged forests with contrasting levels Selva Biological Station, Costa Rica. based experimental approaches have
of protection (Guariguata et al., Une végétation ligneuse et been implemented to investigate how
2000). This is one of the first studies herbacée abondante se développe secondary forests react to manage-
that suggest, through direct research, sous la canopée d’une plantation ment practices. CATIE researchers are
the potential role of fauna in the bio- mixte d’essences indigènes âgées characterizing secondary forest struc-
logical sustainability of some species de neuf ans à la station biologique tures and floristics and developing
de La Selva, Costa Rica.
that are animal-dispersed in managed guidelines for sustainable manage-
Photo F. Montagnini.
forests of the neotropics. La Selva ment in Costa Rica, Nicaragua, Brazil
Biological Station, owned and operat- populations of plants and animals, and Peru (Current et al., 1998;
ed by the Organization for Tropical given the assumption that human Guariguata, 1999).
Studies (OTS), is protected from hunt- intrusion is also controlled. Even if In Costa Rica, CATIE is investi-
ing and connected to a national park, forests are logged with minimal stand gating the effects of silvicultural prac-
whereas Tirimbina remains unprotect- and soil disturbance, sustained tices such as liberation thinning,
ed and is not connected to a park. recruitment of at least mammal-dis- whole-canopy removal, and substrate
Seed dispersal rates by mammals persed timber species appears less preparation techniques on stand
were highest in the protected site. likely if loss of habitat connectivity and dynamics and regeneration of sec-
Seed removal under two protection excessive hunting pressure are com- ondary forests (defined as the woody
treatments (caged vs. uncaged) varied bined. This baseline information may vegetation that regrows after the
both within species across sites and offer a starting point for developing abandonment of farmland or pasture-
within sites across species, as a con- ecological criteria for tree seed reten- land) in order to provide guidelines
sequence of differences in the abun- tion, and it may contribute to improv- for sustainable management of tim-
dance of vertebrate seed consumers ing ecologically-based management ber (Guariguata, 1999). In the
between the two sites (Table I). prescriptions in order to enhance or at Atlantic lowlands of Costa Rica, short-
Twice as many seeds were dis- least maintain sufficient levels of natu- term growth responses in individuals
persed after 50 days of observation at ral regeneration without the need to of four commercial species (Laetia
La Selva (the protected forest) than at rely on artificial regeneration. procera, Simarouba amara, Tapirira
Tirimbina (unprotected). Seed survival
was also higher at La Selva, which is
probably related to altered mammal Table I.
community composition as a result of Number of sightings of mammalian fauna at the study sites in the
hunting pressure and loss of habitat Caribbean lowlands of Costa Rica over a 6 month period.
connectivity at Tirimbina. These Tirimbina La Selva
results confirm earlier findings of Species Number (n/ha) Number (n/ha)
other studies on the so called “fauna Alouatta palliata (howler monkey) 4 (0.06) 8 (0.13)
loss” hypothesis, which have also Ateles geoffroyi (spider monkey) 2 (0.03) 15 (0.24)
shown altered patterns of plant regen-
Cebus capuchinus (white-faced monkey) 7 (0.10) 7 (0.11)
eration due to truncated trophic
chains. In NE Costa Rica, production Dasyprocta punctata (agouti) — 2 (0.03)
forests adjacent to parks and conser- Puma concolor (puma) — 2 (0.03)
vation areas may be more likely to Tamandua mexicana (tamandua) — 2 (0.03)
maintain a wider spectrum of viable
Tayassu tajacu (collared peccary) — 4 (0.07)
Sciurus variegatoides (squirrel) 1 (0.01) 2 (0.03)
Total 14 (0.19) 32 (0.52)
BOIS ET FORÊTS DES TROPIQUES, 2002, N° 272 (2)
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FOCUS / FORESTRY SYSTEMS
Identification and
quantification of
ecological services
provided by
managed forests
CATIE researchers are involved
A mixed plantation of native species at La Selva Biological Station, Costa Rica: Vochysia in the identification and quantifica-
guatemalensis + Jacaranda copia + Calophyllum brasiliense + Stryphnodendron microstachyum. tion of the ecological services provid-
Plantation mixte d’essences indigènes à la station biologique de La Selva, Costa Rica : Vochysia ed by managed forests in terms of
guatemalensis + Jacaranda copia + Calophyllum brasiliense + Stryphnodendron microstachyum.
biodiversity conservation and atmos-
Photo F. Montagnini.
pheric carbon fixing and storage.
Payment for environmental services
Designing systems (PSA) provided by forest ecosystems
for diversified is an innovative Costa Rican mecha-
guianensis, and Vochysia ferruginea) nism that recognizes forest owners’
were evaluated following liberation forest management contributions to the protection of for-
thinning in a young secondary forest. est services (Campos, Ortiz, 1999)
Liberation thinning significantly Designing systems for diversified (Table IV).
increased the diameter growth of forest management involves studies A recent Forestry Act (1996) has
future crop trees with respect to on the ecology and management of established financial and institutional
unmanipulated counterparts (Table several non-timber species, including mechanisms to implement this pay-
II). The study concluded that young trees, herbs and palms used locally or ment system for private farmers who
stands in the region may be attractive regionally for medicinal, insecticidal, protect and manage natural forests
systems for simple silvicultural ornamental, craftwork and construc- and plantations. CATIE researchers
manipulations due to rapid growth tion purposes (Marmillod et al., have recently focused on specific
responsiveness, facilitated by man- 1998). Based on CATIE’s experiences, a case studies to evaluate the feasibili-
ageable tree size (Guariguata, 1999). methodology was developed to incor- ty of these legal mechanisms for the
porate species with non-timber prod- payment of environmental services.
ucts in forestry production processes. Some of these current efforts include:
The use of these resources is based on ▪ selection and evaluation of cri-
a definition of the sustainable supply teria and indicators (CandI) from bio-
Table II. of forest products and on silvicultural logical, economic and social perspec-
Annual median diameter increment (in cm) criteria for each species, as opposed tives, to determine the benefits and
of crop trees of the studied species, two to traditional extraction lacking indica- risks associated with different forest
years after thinning in control and thinned tors of capacity and production limita- ecosystems in biodiversity protection
subplots in a young secondary forest in the tions. The approach requires initial and carbon sequestration services;
Caribbean lowlands of Costa Rica knowledge on the biology and uses of ▪ a study on the benefits which
(from Guariguata, 2000). the species, development of tools to environmental services offer the pop-
characterize its population structure ulation, based on consultations with
and estimate the amount of har- experts and owners of natural forests
Species Control Thinned vestable product, and development of and plantations;
Laetia 0.4 1.0 silvicultural systems and sustainable ▪ studies of carbon fixing and
Tapirira 0.5 1.4 management plans. Examples of cur- storage in secondary forests and
rent studies by CATIE researchers on wood products. Work in this field is
Simarouba 1.7 1.8
non-timber forest products that can be part of the research conducted by the
Vochysia 0.7 1.8 incorporated into diversified forest CATIE’s Latin American Chairs in
All species 0.7 1.2 management systems in the neotrop- Ecology of Managed Forests and in
ics are shown in Table III. Diversified Forest Management.
BOIS ET FORÊTS DES TROPIQUES, 2002, N° 272 (2)
39
GESTION FORESTIÈRE / LE POINT SUR…
Table III.
CATIE research on systems of diversified forest management
(Marmillod et al., 1998).
Topic/result Implication
Quassia amara
Morphological, histological and molecular
characterization of wild populations of Q. amara
in Central America
Statistically significant morphological and histological This highlights the need for studies on:
differences exist among Q. amara populations in diverse Content of active ingredients in different populations
ecoregions of Central America Ecological behavior of the species in response to different
silvicultural systems
Definition of the protocol to extract DNA samples in Provides the opportunity to design molecular
Q. amara leaves characterizations of wild populations of Q. Pamara
Utility of Q. amara as a natural insecticide
Foliage and wood extracts of Q. amara were selected as This result verifies the potential use of this species for the
anti-feedant substances for Hypsipyla grandella, the control of tropical pests, and confirms previous results on the
meliaceae’s shoot borer, among 29 substances evaluated location of active substances within the individual
The anti-feedant effect of wood is higher than foliage
Cardulovica palmata
Environmental preferences
The best environment for C. palmata is low tree canopies C. palmata is an interesting species for multi-strata
and high lateral illumination conditions agroforestry systems
Guidelines for harvesting young shoots (candles)
Productivity of harvesting young C palmata leaves is It is imperative to consider plant size when diagnosing
related to size of individuals and decreases during the populations for sustainable management plans.
production of inflo and infrutescense.
Smaller sized leaves are observed in populations with The study of harvest impact should continue, to prove
continuous and traditional harvesting species robustness levels
Calyptrogyne ghiesebreghtiana
Demography and productivity of C.ghiesbreghtiana
Variables to evaluate productivity are the number of This makes it possible to define the sample elements needed
leaves, stem diameter, and presence of inflo and for inventories to support sustainable use plans
infrutescense
Environmental preferences
C. ghiesbreghtiana prefers slightly compacted soils in This result partially explains the disappearance of the species
lowland and hilly forests with two strata as a result of deforestation
Guidelines for harvesting leaves
Plants with a stem diameter of less than 80 mm are left It is best to harvest leaves from plants of at least 80 mm in
for reproductive development diameter, otherwise flowering will be hampered
The harvest of 50 to 75% of the leaves causes an increase
in the production of inflo and infrutescense.
Zamia skinneri
Population characteristics in the natural area
Statistically significant differences exist among wild Since the seed is the main product harvested, more studies
populations. Larger plants and denser groups are found are needed on phenology of the species in different
in the Lower Talamanca/Teribe areas populations
BOIS ET FORÊTS DES TROPIQUES, 2002, N° 272 (2)
40
FOCUS / FORESTRY SYSTEMS
Hieronyma alchorneoides (pilón), one of the most
successful species at La Selva Biological Station
experiments, is at present being widely planted by
farmers in the region.
Hieronyma alchorneoides (pilón), une des essences
les plus performantes lors des expériences menées
à la station biologique de La Selva, est largement
utilisée par les paysans de la région.
Photo F. Montagnini.
Sustainable
Table IV. forestry options in
Total amounts and annual percentages of payments of environmental communal lands
services in Costa Rica for different forestry options.
Because of their complexity,
Activity Total amount Year and percent of annual many of the more environmentally
(US$/ha) payment per ha sound forest management practices
1 2 3 4 5 are best suited to small farmers, agri-
Forest management 371.5 50 20 10 10 10 cultural cooperatives or community
forest users. Recently, the Smart
Forest conservation
237 20 20 20 20 20 Wood Program certified the opera-
and regeneration
tions of five community concessions
Reforestation 608.6 50 20 15 10 5 in Guatemala that have received sup-
Established plantations 237 50 20 15 10 5 port from CATIE to prepare the techni-
cal/legal framework for granting such
Source: Executive Decree, MINAE-No.26977, 26 May 1998. concessions.
Some farmers’cooperatives in
Costa Rica manage their natural
forests for eco-tourism and non-tim-
Table V. ber forest products, and carry out
Number of trees per hectare, diameter at breast height (dbh), height, other productive activities, including
basal area and volume of native tree species in pure and mixed conventional agriculture, in other por-
plantations at La Selva Biological Station, Costa Rica. tions of their land. For example, the
Coope-San Juan Agricultural Coopera-
Species Trees Dbh Total Basal area Volume
tive, in Aguas Zarcas, NE Costa Rica,
(n/ha) (cm) height (m) (m2/ha) (m3/ha)
has 16 members (eleven men and five
Plantation 1: 86 months women) who, along with their fami-
Calophyllum brasiliense 773 13.73 11.11 11.73 62.21 lies, form a community of about 56
Vochysia guatemalensis 759 21.86 18.39 28.41 244.06 people (Häger, 1998). They collec-
tively own 400 hectares of land, half
Jacaranda copaia 967 18.37 19.85 25.88 238.26
of which is covered with primary for-
Mixture 507 22.82 20.21 21.14 215.99 est. They are keeping their forest
Plantation 2: 81 months intact, have marked trails for tourism
Virola koschnyi 863 17.76 14.21 21.53 141.35 and are expecting to obtain payment
for environmental services from the
Dipteryx panamensis 833 11.73 13.30 8.98 53.96
legal system currently in operation in
Terminalia amazonia 714 16.69 14.25 16.91 115.13 Costa Rica. In their agricultural land
Mixture 878 14.08 13.05 17.21 115.19 they keep a dairy farm and sell the
Plantation 3: 70 months milk locally. They also grow cocoa and
plantains commercially.
Genipa americana 907 10.55 9.00 7.68 33.35
Additionally, they manage non-
Vochysia ferruginea 848 17.7 12.72 21.16 122.1 timber forest species for sale, includ-
Hieronyma alchorneoides 818 13.00 13.66 11.97 81.01 ing a medicinal plant, “raicilla” or
Balizia elegans 1443 11.98 9.68 16.62 86.64
Mixture 952 12.29 11.07 14.33 79.86
BOIS ET FORÊTS DES TROPIQUES, 2002, N° 272 (2)
41
GESTION FORESTIÈRE / LE POINT SUR…
“ipecacuana” (Cephaelis ipecacua- seedlings, or potential pest damage.
na), which they grow in the natural If planned with consideration for each
forest understory. There is an export species’ response to mixed condi-
market for ipecacuana (Germany and tions, mixed schemes can be more
Belgium). In addition, they have been productive than single-species sys-
reforesting portions of degraded agri- tems (Montagnini et al., 1995;
cultural land since 1987 with native Montagnini, Porras, 1998). Mixed
and exotic species, often using stands may also contribute to higher
mixed-species planting schemes. species and landscape diversity
Cooperatives such as Coope- (Lamb, 1998).
San Juan are a promising model for Since 1990, CATIE researchers
more environmentally-friendly fores- have studied growth, productivity,
try systems at small to medium biomass accumulation and financial
scales. For these systems to be suc- aspects in experimental plantations
cessful there may be a need for initial of native tree species in mixed and
economic incentives and training pro- pure stands, at La Selva Biological
grams in cooperative management Station in the humid Atlantic low-
and administration, as well as in the lands of Costa Rica. Of the 12 species
technical aspects of sustainable for- tested in these experiments, the most
est and agricultural management successful (Vochysia guatemalensis,
techniques. Vochysia ferruginea, Hieronyma
alchorneoides, Calophyllum brasi-
Productivity and liense, Terminalia amazonia, Virola
koschnyi) (Table V) are now being
feasibility of planted by farmers on degraded pas-
mixed and pure tures in the region. With estimated
rotation periods of 15-25 years and
plantations of expected standing volumes of 250- Training in technical aspects of forest management,
native species 300 m3/ha on harvesting, planting of ecotourism, and administration is needed in the
initial phases of projects involving communal
these species is attractive for farm-
forestry practices.
Tropical plantations can fulfill a ers. Fuelwood from thinning and Les premières étapes des projets comprenant des
variety of functions including sup- pruning would be an additional pratiques forestières communautaires nécessitent
plies of wood products, carbon source of farm income. une formation sur les aspects techniques de la
sequestration, land reclamation and gestion forestière, l’écotourisme et l’administration.
acceleration of natural regeneration Photo F. Montagnini.
(Lamb, 1998). Results from a series of
trials that were started in the mid-80s
Progeny test of Vochysia guatemalensis. The scheme will allow conversion of the trial
have identified the most promising plantation into a seed orchard at the end of the evaluation period.
native and exotic tree species for Test de descendance de Vochysia guatemalensis. À la fin de la période d’évaluation, le
small farm reforestation of degraded plan d’aménagement prévoit la conversion de cette plantation en verger à graines.
pastures in the lowland regions of Photo F. Mesén.
six Central American countries:
Nicaragua, Costa Rica, Honduras,
Guatemala, El Salvador and Panama
(Ugalde, 1997). In Costa Rica, recent
legislation provides incentives for the
establishment of tree plantations,
especially on abandoned pastures
and other deforested areas. There is
increasing interest among local farm-
ers in making use of these incentives
to plant native species.
In small farm reforestation,
species diversification may be desir-
able because of uncertainties about
species performance, scarcity of
BOIS ET FORÊTS DES TROPIQUES, 2002, N° 272 (2)
42
FOCUS / FORESTRY SYSTEMS
Domestication of Conclusions Acknowledgements
native tree species
There are several ways of imple- Part of the contents of this article was
Over the last twenty years, menting more environmentally- first presented at a sub-plenary ses-
CATIE has developed strategies to friendly forest management systems. sion of the International Union of
domesticate native species with For the systems to be successful, they Forestry Research Organizations
potential reforestation value. Initially, need to be designed with due consid- (IUFRO) World Congress, August 6-12,
many of the species used were not eration for the actual technical and 2000, Kuala Lumpur, Malaysia. The
native to the Central American region. economic capabilities of local users authors thank Jean-Michel Harmand
A stronger focus on native species or managers. They also have to be for translating the abstract into
has been developed at CATIE over the designed in accordance with their French.
last ten years. Strategies for the function in the ecology of the sur-
domestication of native species rounding landscape.
include selecting outstanding or The projects described in this
“plus” trees in natural forests, evalu- article have a number of characteris-
ating genetic variability, research on tics in common: Vochysia guatemalensis has been studied at
the rooting of young shoots, and ▪ they involve production sys- CATIE and other institutions in Central
establishing clonal trials and seed tems that are designed in accordance America, and farmers are willing to plant it
germination and storage trials, evalu- with local human needs; because of its fast growth and consistent
ating species performance under dif- ▪ they are intended to be finan- response.
ferent silvicultural systems, and cially attractive to local farmers; Le Catie ainsi que d’autres institutions en
developing seed orchards for the pro- ▪ they are attuned to the prevail- Amérique centrale ont mené des études sur
Vochysia guatemalensis. Les fermiers sont
duction of genetically improved ing social systems in each region
favorables à son utilisation en raison de sa
seeds. Examples of recent advances (sometimes involving communal sys-
croissance rapide et de sa productivité.
in the domestication of important tems or cooperatives); Photo F. Montagnini.
reforestation species include studies ▪ they try to reconcile production
on Vochysia guatemalensis Sm., J.D., with biodiversity conservation or
a fast-growing timber tree, found nat- restoration;
urally in the wet lowlands from south- ▪ they aim to make use of local
ern Mexico to Panama (Mesén et al., biodiversity, including non-timber for-
1999). Similar work at CATIE with est products, by designing diversified
other native species is focusing on forest management systems;
Alnus acuminata, Cupressus lusita- ▪ whenever possible, they make
nica, Bombacopsis quinata, Albizia use of native species;
guachepele and others (Cornelius, ▪ they include strategies to
1997; Cornelius, Mesén, 1997). restore degraded ecosystems;
▪ they make use of the existing
legal system (forestry or environmen-
tal legislation);
Clearing, weeding, site marking and tree planting make ▪ in turn, the projects aim to
the initial stages of reforestation expensive. Government advise or modify the local legal sys-
subsidies are needed to cover the initial stages of tem regarding such policies.
projects to encourage small farmers to undertake These characteristics identify
reforestation projects. such projects as “environmentally
L’abattage, le nettoyage, le marquage et la plantation friendly”, although we are not advo-
rendent coûteuses les premières étapes du reboisement. cating them here as the only possibil-
Afin d’encourager les petits fermiers à entreprendre des
ities for systems of this type. Under
opérations de reboisement, des subventions
gouvernementales sont nécessaires.
different ecological, social or eco-
Photo F. Montagnini. nomic conditions, other characteris-
tics may appear as more important
for environmentally-friendly forestry
systems.
BOIS ET FORÊTS DES TROPIQUES, 2002, N° 272 (2)
43
GESTION FORESTIÈRE / LE POINT SUR…
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BOIS ET FORÊTS DES TROPIQUES, 2002, N° 272 (2)
44
FOCUS / FORESTRY SYSTEMS
Synopsis
SYSTÈMES FORESTIERS variées, mais aucun changement profond tales d’essences indigènes, en peuple-
ÉCOLOGIQUES n’a pu être mis en évidence durant le pre- ments purs ou mélangés, à la station bio-
EN AMÉRIQUE CENTRALE mier cycle d’abattage, même dans des logique de La Selva, située dans les
peuplements dont la structure a été alté- plaines humides de la côte atlantique du
F. MONTAGNINI, J. J. CAMPOS, rée par des traitements d’amélioration ou Costa Rica. Des douze essences testées,
J. CORNELIUS, B. FINEGAN, de dégagement. L’appauvrissement fau- celles qui ont obtenu les meilleurs résul-
M. GUARIGUATA, D. MARMILLOD, nistique et les bouleversements du micro- tats (Vochysia guatemalensis, V. ferrugi-
F. MESÉN, L. UGALDE environnement forestier peuvent aussi nea, Hieronyma alchorneoides, Calophyl-
affecter l’ensemencement naturel et la lum brasiliense, Terminalia amazonia,
La variété des pratiques forestières germination. Virola koschnyi) sont désormais régulière-
peut considérablement amoindrir les Les chercheurs du Catie sont également ment utilisées par les fermiers pour reboi-
conséquences de l’aménagement des impliqués dans l’étude de plans d’exploi- ser les zones pastorales dégradées de la
forêts sur la biodiversité, rendant cette tation forestière diversifiée, comme, par région. Avec des temps de révolution esti-
gestion compatible avec le principe de exemple, l’écologie et l’exploitation de més de 15 à 25 ans et des volumes de
rendement soutenu et la préservation de produits forestiers non ligneux ou l’éva- coupe attendus de 250 à 300 m 3 /ha, la
la biodiversité. Afin de rendre ces pra- luation de services écologiques rendus plantation de ces essences offre un attrait
tiques plus « écologiques », les pro- par les forêts. Nombre de ces pratiques certain pour les fermiers.
grammes de gestion sylviculturale se sont d’exploitation conviennent aux petits La domestication d’essences promet-
concentrés sur la réduction des dom- exploitants, aux coopératives ou aux utili- teuses pour ces plantations implique la
mages forestiers en diminuant l’intensité sateurs des forêts d’État. Certaines coopé- sélection d’arbres de première valeur,
de l’exploitation et en améliorant ses pra- ratives au Costa Rica exploitent les forêts l’évaluation de la variabilité génétique, le
tiques. Nous présentons ici des exemples dans une perspective écotouristique, stockage et la germination des semences,
de recherches en aménagement durable tirant des revenus de produits autres que l’évaluation des performances des
des forêts effectuées par le Centre agrono- le bois d’œuvre, tout en cultivant des par- essences sous divers systèmes sylvicultu-
mique tropical de recherches et d’ensei- celles arables et en reboisant les terres raux et le développement de pépinières
gnement (Catie) situé à Turrialba, au Costa dégradées avec des essences indigènes pour la production de semences généti-
Rica. Ces études comprennent l’utilisation ou exotiques, souvent dans des planta- quement améliorées.
de produits forestiers autres que le bois et tions mixtes. Les projets décrits dans cet article font
la mise en valeur des services écologiques appel à des systèmes de production défi-
rendus par les forêts. Par ailleurs, elles Productivité et faisabilité de plantations nis en accord avec les aspirations de la
envisagent des stratégies de récupération d’essences indigènes pures ou mixtes population locale. Ils se veulent financiè-
d’écosystèmes dégradés, y compris le Les plantations tropicales sont en mesure rement attractifs pour les paysans et en
reboisement à partir d’essences locales. de fournir du bois d’œuvre, de contribuer harmonie avec le système social qui pré-
Les études ici décrites font partie de pro- à la production de carbone, à la restaura- vaut dans les régions concernées, impli-
grammes plus larges visant à élaborer de tion des terres et à l’accélération de la quant parfois des fonctionnements com-
nouvelles techniques de gestion forestière régénération naturelle. Les chercheurs du munautaires ou coopératifs. Ils concilient
durable. Catie ont identifié les essences indigènes les besoins productifs et la conservation
et exotiques les plus prometteuses pour le de la biodiversité sur laquelle ils s’ap-
Pertinence économique et écologique reboisement par les petits agriculteurs puient, sans exclure les produits forestiers
de la gestion forestière des zones pastorales dégradées des autres que le bois, diversifiant ainsi les
Au Catie, la recherche à long terme s’est basses terres du Nicaragua, du Costa Rica, plans d’aménagement forestier. Chaque
concentrée sur les technologies de ges- du Honduras, du Guatemala, du Salvador fois que c’est possible, ils font appel à des
tion durable des forêts tropicales et leur et du Panama. Au Costa Rica, la législation essences indigènes. Pour la récupération
biodiversité. À partir d’études sur la faisa- encourage toute nouvelle plantation, en d’écosystèmes dégradés, ces projets
bilité économique et les conséquences sur particulier sur les zones pastorales aban- incluent toute une gamme de stratégies et
la biodiversité, il a été établi qu’au moins données. ils s’appuient sur le système légal en
30 ha et 10 à 15 m3 par hectare devraient La diversification des essences offre vigueur (législation forestière ou environ-
être exploités pour rendre cette gestion maints avantages du fait des incertitudes nementale). Ils peuvent conseiller les
économiquement attractive. Les traite- sur les performances de certaines es- acteurs de ce système légal local, voire
ments post-abattage améliorent l’accrois- sences, de la rareté de certains plants ou l’amender.
sement, en particulier en ce qui concerne des risques de dommages par les rava- Les possibilités d’aménagement forestier
les essences commerciales. L’exploitation geurs. Par ailleurs, s’ils sont bien planifiés écologique sont nombreuses. Les plans
fondée sur des techniques de gestion et gérés, les systèmes forestiers mixtes mis en place doivent tenir compte des
durable permet une meilleure régénéra- peuvent se révéler plus productifs que les capacités techniques et économiques
tion des plants et une plus grande biodi- systèmes monospécifiques. Depuis plus réelles des acteurs locaux. Enfin, ils doi-
versité des strates inférieures que l’exploi- de dix ans, les chercheurs du Catie étu- vent aussi prendre en compte l’impact
tation conventionnelle. L’exploitation dient la croissance, la productivité, la pro- qu’ils peuvent avoir sur l’écologie des pay-
forestière affecte la diversité végétale de duction de biomasse et les aspects écono- sages environnants.
différentes façons et sur des périodes miques à partir de plantations expérimen-
