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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
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                               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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                       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)
                                                                                                                                             37
                                                                                             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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                                                                                                             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
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                            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-

				
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