SILVA, J. N. M.

UHL, C.

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Forest Management for Timber Production: a Sustainable use of theBrazilian Amazon.JOSÉ NATALINO MACEDO SILVA and CHRISTOPHER UHLEMBRAPNCPATU, Caixa Postal 48, 66017-970 - Belém, Pará - BrazilABSTRACTLogging in Amazonia is a source of wealth but also a cause of concern because of destructive harvestpractices. Logging is practiced in both the upland and floodplain forests of Amazonia. The number ofspecies cut varies from very few in the selective logging of floodplain forests to more than a hundred inthe intensive logging of upland forests. Intensive logging in both upland and floodplain forests can causesevere damage, modifying, sometimes drastically, forest structure and composition.Roundwood production in Amazonia rose from 6.7 to 24.6 million cubic meters in the period from 1976-1988, and presently represents more than half of Brazil's total. Logging is lucrative: a typical sawmill,engaged in both logging and wood processing, realizes a net profit of more than $200,000 per year.Forestry and wood processing activities could create about one job per 200 hectares of forest -- more thantwice the employment generated by cattle ranching on an aerial basis.World concern with the future of tropical forests has grown recently and has motivated environrnentalgroups to contemplate campaigns to boycott tropical wood from non-sustainable sources. Meanwhile,there has been almost no effort to manage the Amazon forest sustainably, nor has there been muchprogress in the establishment of mixed-species plantations of native species on degraded Amazonianlands. However, there are no serious technological barriers to the practice of sustainab1e forestry. Thescientific knowledge exists for the management of natural forests as well as the establishment of mixed-species plantations of native species. What is lacking is the political will to apply this knowledge.Agro-ecological zoning of Brazilian Amazonia is the necessary starting point for the implementation of awise forestry policy. It is imperative to create forest reserves of sufficient size to guarantee the preserva-tion of the principIe forest ecosystems of Amazonia, as well as to demarcate areas for production forestry.Alternatives are presented for the sustainab1e use of Amazonia's forest, together with suggestions for howranchers, farrners, and forest dwellers can integrate forest management and tree planting in their produc-tion systems.Keywords: natural regeneration; silvicultural systems; sustainable management; Brazil;Amazonia1. INTRODUCTION is a source of wealth but also a cause of concernbecause of destructive harvest practices.With the volume of wood estimated at about45 billion cubic meters, of which approximately13 billion have commercial value (Nascimentoand Homma, 1984), the Brazilian Amazon is in aunrivaled position to become the principIe sup-SOClo-EcONOMIC IMPORTANCE OF FOREST USEIN AMAzONlABrazil has the largest continuous expanse oftropical forest in the world. Logging in AmazoniaAn. Acad. bras. Ci., (1992) 64 (Supl. 1)90 JOSÉ NATALINO MACEDO SILVA AND CHRISTOPHER UHLplier of tropical woods for the world, as theAfrican and Asian reserves beco me depleted.Even today, the socio-economic importance offorestry to Amazonia is obvious: the income fromforest wood extraction and processing is surpassedonly by that derived from mining (Yared, 1990).Even so, this advantageous situation could worsenwith increasing pressure from environrnentalistgroups directed against the use of tropical woodsoriginating from non-sustainable sources, present-ly the case in Brazilian Amazonia.There are four main logging patterns inAmazonia. These patterns are defined by the typeof forest (upland or floodplain), and the intensityof logging (highly selective or intensive). Themost traditionallogging pattern is highly selectivelogging in floodplain forests (Fig. 1). In thismodel, few species are extracted and the volumeharvested per hectare is very low. This type oflogging does not harm the forest, but it also doesnot bring social benefits to local populations be-cause of low production and because woodprocessing is done far from the logging areas.Recently, on the floodplains, a much more inten-sive type of logging has started in which large, aswell as small, trees (down to 15 em in diameter)of some 50 species are harvested. This intensivefloodplain logging is practiced mostly by localpopulations and significantly alters the structuralcharacteristics of the forest, frequently leading toa forest dominated by palms and vines (Fig.l).In newly opened frontiers in regions ofupland forest (e.g., forest bordering Para highway150), logging is highly selective with only about adozen species of high value being extracted (e.g.,Tabebuia serratifolia (ipê), Caryocar villosum(piquiá), Manilkara huberi (maçaranduba), amongothers). This selective logging does not harm theforest, but, in general, the entrance of loggerscatalyzes subsequent forest clearing by ranchersand small farmers. In old frontier areas (e.g.,forest along the Belem-Brasilia highway), loggingis much more intensive, involving more than 100species. The forest is severely darnaged duringthis intensive logging (Fig. 1).Logging is expanding rapidly throughoutAmazonia. For example, from 1976 to 1988An. Acad. bras. Ci., (1992) 64 (Supl. 1)roundwood production in the Brazilian Amazonincreased from 6.7 to 24.6 million cubic meters,representing 54% of Brazil's total in 1988. Thisindicates that, at last, the forest is being valued forthe wood it contains.Logging can be quite lucrative. For example,a typical sawmill in the eastem Amazon, involvedin forest extraction and wood processing realizes anet profit of approxirnately $200,000 per year(Verissirno and co-authors, in press). By takingsteps to carefulIy harvest and manage the forest,logging industries could guarantee future woodharvests. However, up to now, most mills engagein careless logging practices which could con-tribute to the slow degradation of Amazonia'sforest.Studies conducted around Paragominas ineastem Amazonia show that forest managementand wood processing activities could employabout one person per 200 hectares of forest. To ar-rive at this figure, an area of 10,000 hectares wasconsidered as the area necessary to supply a typi-cal sawmill sustainably, given a cutting cycle of35 years and wood production of 30 m3 ha-1 percutting cycle. Such a sawmill would employ 30people, as well as 12 forest loggers and 8 workersinvolved in the application of silvicultural treat-ments, giving a total of 50/10,000 ha or 1/200 ha.This is more than twice the number of jobsgenerated per unit land area in cattle ranching,even considering the employment associated withcattle slaughtering.2. SILVICULTURAL ALTERNATIVES FORSUSTAINABLE PRODUCTION OF WOOD INTHE BRAZILIAN AMAZON2.1 NATURALSILVICULTUREMany people feel that there is insufficientknowledge to manage tropical forests for tirnberproduction. However, there are examples of sue-cessfully managed forests in several tropicalcountries (Dawkins, 1988). The criteria used toevaluate the success of management is thecapacity of the forest to produce high value timberafter silvicultural treatments compared to theTERRA FIRME VARZEASELECTIVE SELECTIVE INTENSIVEINTENSlVE'E";~".'-~..:. ...h. ~~ •••••:" .... .. . .. .'. .'. . .' .'. •••••••'. . .'. ': . .'. . .'. .. . ...'jWllt}; '~ ...U;· 'I':'~~'\i""fIVl_~"l·~:·:;·:?". ~..\1~.;<v, '1i" ~~'i;,t,il.R]jt C:i:i.L~ ._ •••.• ~r •• '&_~;>~g!'>-~(]!"'LOCATION SPARSELY SETILED WELL SETILED SPARSELY SETTLED WELL SETTLEDAREAS/New fronl iers AREAS/Old fronlie rs AREAS AREASLOGGIt«>CHtlW:TERISTICS :-N!? species exfrocled 5-15 100 1-5 40-60- ~kJme exlrocled (m3/ 00) 10-20 30-60 3-10 50-100-<:onopy domoge(% opening ) 5 - 10 40- 60 5-10 40- 60~•...•'O§tVic::~Fig. 1 - Characteristics of logging in the terra firme and varzea forest eastern Arnazonia. (Arnazonia Institute of Men and the environment - lMAZON).c'TlO§~~~d~~I:ó~'"C~Ot::::Ic:BOz'O•...•92 JOSÉ NATALINO MACEDO SILVA AND CHRISTOPHER UHLproduction of high value timber in the absence ofmanagement. On the Malaysian peninsula Dip-terocarp forests, logged 50 years ago and treatedsilviculturally, are being re-logged (S. Korsgaard,personal communication, 1991), suggesting thatsustainable timber production might be possible aslong as there is responsible extraction and effortsby loggers to encourage the regeneration andgrowth of desirable species.A proposed silvicultural system for sus-tainable management of Amazonian forests (Silva,1989) recommends timber extraction at intervalsof 30 years, extracting 40m3 ha-1 of high valuewood in each cycle.A planned extraction is the critical startingpoint in the forest management system recom-mended by Silva (1989). Prior to harvest the standshould be inventoried and the location of desirabletrees should be mapped. Trees should then be cutto avoid the creation of large canopy gaps and tominimize the damages to the remaining trees(stock for the next cut). Therefore, oriented fellingshould be tried whenever possible. In addition, thearea devoted to skid trails and log landings shouldbe kept as small as possible and these access pathsshould be reutilized whenever possible. Speciesthat grow rapidly in the open could be planted inlog landings.Also important are silvicultural treatments topromote better growing conditions for futurecrops. Openings in the canopy created by the firstcut improve growing conditions, but this lastsonly a couple years (3-4 years in the case ofEMBRAPA research in the Tapajos nationalforest; see also de Graaf, 1986). Hence, periodicthinning and vine cutting are recommended to freedesirable trees from competition for light andnutrients. Open conditions are known to be corre-lated with improved growth rates of tropical trees(Bryan, 1981; Korsgaard, 1986; Silva, 1989). Theestimated interval for the application of these thin-ning treatrnents is ten years.A third and very important part of Silva's(1989) forest management system is the monitor-ing of tree growth during the interharvest periodto determine the tirning of silvicultural treatrnents.An. Acad. bras. Ci., (1992) 64 (Supl. 1)Research to date shows that managementleads to increased production and healthierforests. For example, carefully planning forest ex-traction operations reduces the damages caused bylogging by half (Marn and Jonkers 1981; Appanahand Putz, 1984; Hendrison, 1990), and simplethinning treatments at ten year intervals, such aswe recommend here, increases the accumulationof commercially valuable wood volume 4 to 10times over that recorded in unrnanaged forest (deGraaf, 1986). Thus, the volume of wood accumu-lated over 30 years in managed forest is easily 5times greater than that accumulated in unmanagedforests. Although there is only a 3-6% retum onthis management investment, these measuresshould guarantee long-term sustainable forestproduction (Verissimo and co-authors, in press).Without management, the forest will bedegraded over time, creating a new ecosystem fullof vines, poor in commercial wood species, andmore susceptible to fires. Indeed, consecutive ex-tractions at short intervals increases damage togrowing trees and interferes with the naturalregeneration which establishes itself after logging.Therefore, logging should be done in a singleepisode with no heavy machinery permitted in themanaged forest between logging episodes.Moreover, in the period between harvests, asidefrom silvicultural treatrnents, only regulated hunt-ing and extractive activities that don't harmregeneration should be permitted.2.2 PLANTATION SILVICULTUREFamiliarity with the silvicultural behavior ofnative and exotic species in single or multi-species plantations is relevant especially forspecies subjected to heavy logging pressure (e.g.,Swietenia macrophylla (mabogany), Virolasurinamensis (virola), and Torresia cearensis(cerejeira), among others ). The silvicultural be-havior of more than a hundred native species anda couple dozen exotic species has been observedin experimental plantations in Amazonia undervarying conditions (e.g., in open areas, second-growth stands and in agro-forestry systems).FOREST MANAGEMENT FOR TIMBER PRODUCTION 93SUSTAINEO FOREST MANAGEMENT~ (FUNOING RESTORATIONOFOEGRA;- -H;;N~R-; 0i HUSBANORY OEO PASTURES).--- + ~1 ANO I TIMBER1 CROP FARMER I - REFORESTATlON FOR ENERGYI I ( CHARCOAl; FIREWOOD)AGROFORESTRy0r--- '--FARMERI ANNUAL CROPS + PERENHIALSHI FT1 NG CROPS( FRUIT TREES AI«l/OR'-- ~ AGROFORESTRY nMBER TREES)CULTIVATION SYSTEMSANNUAL CROPS+ FASTGROWI NG TIMIIER TREESFOR CHARCOAL/FIREWOOOr---I-----~I TIMBER 0, SUSTAINEO FOREST MANAGEMENT: EXTRACTOR :~(PRIMARY FORESTS)~LA 1 IA N 0 PLANTATION OF INTENSIVELYC O FORESTTFARMERLOGGEOSPECIES( EG. MOGNO,O U VI ROLA ,CEREJEIRA, ECT, ----R S ON DEGRADEDFOREST LANOS PRIVATE ANOS E -ISTATE FOREST LANOSN S AGROFORESTRY 0Y f-- ~T S SYSTEMSH TE EM EXTRACTlVISM ANO 0- -CONTROLLEO HUNTING1-------:-,I NON-TIMBER0 I- : PRODUCTS : ri SUSTAINED FOREST MANAGEMENT 0 PRESENT SITUATIONI EXTRACTOR II o PROPOSEO SITUATIONEXTRACTlVE 0'-- AGROFORESTRY SYSTEMS 0 ALLOWEO TOTHE FAMIL1ES OFFARMER FOREST WORKERSY CONTROLLEO HUNTlNGFig. 2 - Proposal of alternatives for different systems of suistanab\e forest land uses in the Brazilian Amazon.We do not advise the substitution of na tiveforests by plantations, even though such planta-tions may be more productive. However, planta-tions might be appropriate on degraded lands inareas with a high. demand for pulpwood, charcoalor firewood, or when the intention is to increasethe land value by introducing forest species ofhigh commercial value into altered landscapes oflow value. But, we stress that plantations arerecommended only in areas of already disturbedforest or in abandoned pastures.According to Yared and Brienza Junior,(1989) if just 10% of the area that is fallowed eachyear in shifting cultivation were used in reforesta-tion programs in Amazonia, approximately 40,000hectares/year could be incorporated into forestryproduction, with possible economic returns to theproducer. For agro-forestry systems, species suchAn. Acad. bras. Ci., (1992) 64 (Supl. 1)94 JOSÉ NATALINO MACEDO SILVA ANO CHRISTOPHER UHLas Bertholethia excelsa (Brazilnut), Carapaguianensis (andiroba), and Dipteryx odorata(curnarú) are desirable because they produce high-value products and because their seeds are readilyavailable.3. CONCLUSIONS AND RECOMMENDATIONSScientific knowledge about forest manage-ment and tropical forest function makes possiblethe establishment of a forestry developmentpolicy for the Brazilian Amazon. Agro-ecologicalzoning of Amazonia is the necessary starting pointfor the development of this forestry policy. Zoningshould include the creation of forest reserves ofsufficient size to guarantee the preservation of theprincipIe forest ecosystems in the region, as wellas the demarkation of areas for productionforestry.The economic, social, and environmental im-plications of irresponsible forest use justify amore rigorous control from state and federalauthorities. In countries in Southeast Asia, such asMalaysia, all forest lands are property of the state(S. Korsgaard, personal communication, 1991).Canada also maintains most (90%) of its forests asstate property (1. Yared, personal communication,1991).Figure 2 provides suggestions for howforestry might be integrated into present-day landuses in Amazonia. Starting with ranching, we sug-gest that this land use might interface with lurn-bering activities in two ways. In the case ofranchers who control large tracts of forest, werecommend measures that stimulate sustainableforest management. Revenues from sustainableforestry could be used by ranchers to periodicallyrestore degraded pastures. For ranches located inregions where there is a demand for charcoal andfirewood (e.g., Programa Grande Carajas), werecommend reforestation activities on degradedpastures using fast growing, plantation-typespecies.In colonization areas where itinerate agricul-ture is practiced, we recommend that agro-forestrysystems be established on fallowed lands todiminish deforestation and increase family incom-An. Acad. bras. Ci., (1992) 64 (Supl. 1)es. In this case, the use of combinations of short-lived food crops with perennial crops (fruiting andwood producing trees) or rapidly growing treessuitable for charcoal production are recom-mended.In areas of virgin forest, we recommendforest management following the guidelines ofSilva (1989) as outlined above. At the same time,intensively logged species (e.g., Swietenia macro-phylla (mogno), Cordia goeldiana (freijó), Virolasurinamensis (virola), Torresia cearensis(cerejeira), among others) might be raised inmixed-species plantations in cut-over areas (Fig.2).Finally, considering the extractivist producer(i.e., forest dwellers), we recommend measures toincrease income and sustainability of forest ex-traction activities. These measures may includeforest management for timber production, agro-forestry with annual and perennial crops, control-led hunting, and/or the raising of wild animaIs.REFERENCESAPPANAH,S. & Ptrrz, F.E. (1984), Climber abundancein a virgin dipterocarp forest and the effect ofpre-felling climber cutting on logging damage. TheMalaysian Forester 47: 335-347.BRYAN, M.B. (1981), Studies of timber growth andmortality in the mixed dipteropcarp forest inSarawak. [FAO Report] no FO:MAL/76/008. FieldDocument 11. 56 p.DAWKINS,H.C. (1988), The first century of tropicalsilviculture: successes forgotten and failuresmisunderstood. In: The Future of the Tropical RainForest. Proceedings of an intemational conferenceheld in Oxford, England, in the period of June27-28,1988. Oxford Forestry Institute. p. 4-8.DE GRAAF, N.R. (1986), A silvicultura I system fornatural regeneration of tropical rain forest inSuriname. Agricultural University, Wageningen,The Netherlands.HENDRISON,J. (1990), Damage-controlled logging inmanaged tropical rain forest in Suriname.Agicultural University, Wageningen, TheNetherlands.FOREST MANAGEMENT FOR TIMBER raooucno»KORSGAARD,S. (1986), An analysis of the potential fortimber production under conservation managementin the tropical rainforest of South East Asia. Aninterim project report. The Research Council forDevelopment Research. Copenhagen. 83 p.(unpublished).MARN, H.T. & JONKERS,W. (1981), Logging damagein tropical high forest. [FAO Report]nO.MAL/76/008. Working Paper 5.NASCIMENTO,C.N.B. DO & HOMMA,AK.O., (1984),Amazonia: meio ambiente e tecnologia agricola.EMBRAPA-CPATU, Belém.SILVA,J.N.M., (1989), The behavior ofthe tropical rainforest ofthe BrazilianAmazon after logging. DPhilThesis. University of Oxford.95VERISSIMO,A; MArros, M.; TARIFA, R.; & UHL, C;(in press). Logging impacts and prospects forsustainable forest management in an oldAmazonian frontier: the case of Paragominas.Forest Ecology and Management.YARED,J.A.G. & BRIENZAJUNIOR,(1989), A atividadeflorestal e o desenvovimento da Amazonia. ParaDesenvolvimento 25: 60-64YARED, J.AG., (1990), A atividade florestal naAmazonia: diagnosticos e perspectivas.Conference presented at the seminar FuturoEconomico da Amazonia: Agricultura, held inBrasília, Federal Senate, 23-24 of May, 1990.(unpublished).23p.An. Acad. bras. Ci., (1992) 64 (Supl. 1)

Forest management for timber production: a sustainable use of the brazilian Amazon.

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Forest management for timber production: a sustainable use of the brazilian Amazon.

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