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Please cite
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Fearnside, P.M.
1989. Forest management in Amazonia: The
need for new criteria in evaluating development options. Forest
Ecology and Management 27(1): 61-79.
ISSN: 0378-1127
Copyright: Elsevier
The original publication is available at: http://www.elsevier.com.nl
FOREST MANAGEMENT IN AMAZONIA:
THE NEED FOR NEW CRITERIA IN EVALUATING
DEVELOPMENT OPTIONS
Philip M.
Fearnside
National
Institute for
Research in
the Amazon (INPA)
C.P. 478
69011 Manaus‑Amazonas
BRAZIL
August 3, 1987
revised: April 18, 1988
Published
Forest Ecology and Management 27: 61-79. (1989)
ABSTRACT
Sustained
management of Amazonian forest is nonexistent on a commmercial scale and is in
its infancy as a research front. Systems
are under trial in Brazil, Surinam, French Guiana and Peru to overcome
technical barriers to sustained production.
The low priority that has been given to developing and implementing
sustainable systems is a reflection of the low weight given to future costs and
benefits in presently‑used economic calculations. An examination of presently‑used
criteria in Amazonia suggests that they do not lead to development choices that
are in the best interests of the region.
Problems include: the lack of connection between discount rates applied
to future returns and the biological rates limiting forest growth;
inappropriate accounting for environmental and social factors; and common
property effects‑‑including the distribution of environmental
costs. The result is destruction of the
forest, along with its potential for sustainable production through forestry
management. Alternatives must be
evaluated on the basis of contribution to the well-being of the present
residents of the Amazon region and their descendants.
"A
human being is worth much more than any economic index"
Tancredo Neves,
January 15, 1985,
in his address on
the occasion of his election as President of Brazil.
INTRODUCTION
The blind
pursuit of inappropriate economic indices is currently causing explosive
deforestation in Amazonia and sacrificing the future well-being of the region's
residents. Against this background of
helter‑skelter "disordered" occupation lies what is perhaps one
of the greatest opportunities on the planet for planners to have a real impact
on the shape of development for centuries to come. This is because Amazonia is, for the moment,
still blessed with a relatively small population and vast areas of minimally-disturbed
forest. Brazil's 5 X 106 km2
Legal Amazon region had a 1980 population of about 12 million, 52% of which was
rural (Brazil, IBGE, 1984).
Approximately 8% of the Legal Amazon had been deforested by 1988; the
cleared area is increasing at about 35,000 km2 annually assuming a
linear trend since the last two years for which satellite data are
available. Although the forest is not so
vast as many believe, and the agricultural potential of its soil when cleared
is also limited, today the opportunity for rationally-planned development is
still very real. It therefore behooves
all those whose work affects the region, including researchers, planners, and
decision‑makers, to spend some time thinking about how development
decisions in the region are made.
Before
one can rationally compare options, one must clearly define criteria to be used
and the method for balancing conflicting needs and interests in arriving at a
decision. As a start towards
constructing a framework for evaluating forestry development options in
Amazonia, I will examine the assumptions implicit in the criteria used in
forest management and suggest an alternative approach to evaluation. As the Chinese say: "a journey of a
thousand leagues begins with a single step."
PRESENTLY‑USED CRITERIA
Net Present Value
The
normal criteria used for comparing investment choices almost invariably involve
calculation of the net present value (NPV) of the expected returns. The logic underlying these calculations fails
to indicate choices that really attain the objectives of planners, at least if
these objectives were more completely explicit.
This applies especially to decisions involving management of natural
forests.
The net
present value expresses the amount of money that a long‑term income would
be worth if the rights to the income were to be sold as a package today. First, it is worthwhile to contemplate
whether such a monetary value really expresses all that the decision‑maker
wants. Is making the most money today
really our objective? The money we make
today can be passed on by inheritance to our children and grandchildren who, we
implicitly expect, will be able to use it to buy a better life proportional to
the amount of money passed on. This
assumption may be mistaken. The heritage
that our children and grandchildren need to inherit most is not a still greater
quantity of money which, even correcting for inflation, will not buy back
things that have been destroyed‑‑especially natural ecosystems like
forests. The physical resource, capable
of continued and sustained production, is much more fundamental to pass along
than are bank accounts or bars of gold.
Myers (1983) summarizes the value of keeping substantial stands of
tropical forests, while Weiss (1984) outlines the ethical justifications and
legal mechanisms for passing an environmental heritage such as this to future
generations.
The
environmental services now performed by natural ecosystems, such as recycling
water in the atmosphere to maintain the amount and regularity of rainfall, are
not easily replaced. This reflects other
drawbacks of strictly monetary criteria as a basis for investment decisions: as
usually applied, monetary computations do not account for such costs as
pollution, climatic change and the aggravation of social inequalities and
tensions.
In
addition to the inadequacy of money being used as the index used for expressing
the desired goal (future well-being), the way the calculations are made also
contributes to the long list of past and present environmental disasters that
common sense tells us will worsen the human condition for years to come. These are often put down to incompetence, bad
luck, or short‑sightedness‑‑but actually many of these can be
better explained as perfectly competent application of accepted decision rules
that are founded on faulty logic.
Discount Rates
Rapid
discounting of future events and benefits, as compared with those expected over
the short term, has so far obstructed development and application of sustainable
forestry systems. The usual way to
calculate the net present value of a potential investment, such as a forestry
scheme, devalues future production and cost by a discount rate. For example, if one assumes that inflation is
adequately corrected for by a scheme such as Brazil's National Treasury Orders
(OTNs: a monetary index adjusted for inflation monthly which is used for many
debt and price schedules), then a value today‑‑for example 1000
OTNs‑‑ with a discount rate of 10% per year, can be thought of as
equivalent to 100 OTNs received this year, plus a value to be received next
year expressed as 100 OTNs / 1.10, plus a value to be received the following
year expressed as 100 / (1.10)2, and so forth, the exponent of the
denominator increasing by one each year.
The term "1.10" in the denominator represents the 10% discount
rate. The example in Table 1 illustrates
the way that discounting leads to destruction of potentially renewable
resources like forests. In this
hypothetical case, an arbitrary 100-year time-horizon is used in comparing
destructive exploitation with sustainable management. Computations are made using discount rates of
3% and 10%, assuming that the cost of a one-time destructive harvest is five times
the annual cost of sustainable management, while the sale value of the clearcut
forest is ten times that of the annual sustainable harvest. Destructive exploitation is indicated when
the 10% discount rate is used, whereas sustainable management is favored under
the 3% rate. The example makes evident
the great speed with which future costs and benefits are devalued when commonly‑used
rates (such as 10%) are applied. This
situation inevitable leads to decisions that favor even modest short-term gains
over what may be tremendous long-term benefits, and that can ignore literally
catastrophic long-term costs.
(Table 1)
When
the values of various options are compared, their NPVs are judged against a
standardized discount rate that reflects the income that can be obtained by investing
in other alternative activities. The
conclusions made are often highly sensitive to the discount rate used. Alternatives for an individual investor would
include lending the money to someone else by putting it in a savings account at
a bank. A large company might be
comparing profits obtainable from investing in long‑term management of
Amazonian forest with those expected from cutting down forest to plant Eucalyptus
or cattle pasture, or from undertaking investments in completely different locations
and sectors of the economy.
Selecting
discount rates for financial analyses is an entirely subjective process,
despite the superficial impression of objectivity given by the numerical
computations in which these rates are used.
Discount rates can be selected either above or below a
"switchover" value at which a cost‑benefit analysis will
indicate whatever conclusion the analyst might wish. A.J. Leslie (1987a,b) has eloquently argued
that the high discount rates used in financial analyses systematically
underrate the profitability of managing natural regeneration in tropical
forests, and that economic merits alone are sufficient to make this the
rational land use choice in much of the tropics.
Financial indices vs. biological limits
The problem
with financial analyses using discount rates based on income potential from
alternative investments is that the rates of return to be expected from, say, a
new factory in southern Brazil's CubatÔo industrial area are fundamentally
different from the biological rates that limit the rate of return one can
obtain from Amazonian forest. The rates
at which trees grow and reproduce to replenish individuals removed from a
population are low, and can only be increased by human intervention up to a
point‑‑a point that is still quite limited and still has no logical
connection whatsoever with the returns available from alternative investments
in other sectors of the economy. When
standard discount rates (on the order of 10% per year) are compared with
returns from the forestry sector (on the order of 3% per year), the forest is
sacrificed for unsustainable uses with higher short‑term returns. The madness of this "logical"
choice should be obvious.
Ways of
shifting the balance toward sustainable management include use of lower
discount rates for judging forestry projects (e.g. Row et al.,
1981), adjusting present value calculations to correct for expected increases
in the value of forestry products relative to other commodities (Overton and
Hunt, 1974), increasing the weight given to future costs (McDonald, 1981),
using shadow prices in the calculations to reflect forestry's social benefits
(Harou, 1984), and assigning additional weight to irreversible costs such as
species extinctions (Goodland et al., 1986). Separate discount rates can be assigned to
different groups within the population to improve either the ability to
forecast the likelihood of systems being adopted (Hoekstra, 1985) or the
normative value of project identification for support by government agencies
(Price and Nair, 1985). Cost‑benefit
analysis can make significant contributions to improving decision‑making
provided the definitions of alternatives, social pricing of resources and
products, and procedures for selecting among the alternatives are correct
(Price and Nair, 1984). In practice,
however, cost‑benefit analyses (including their discounting provisions)
are frequently manipulated to add legitimacy to projects that have already been
chosen for political or other unstated reasons (see Price and Nair, 1984). Adjustments of cost-benefit analysis
procedures to incorporate non‑financial concerns are rarely made in
practice: simple calculation of net present value remains the core of most
decision‑making. Even most
improved formulations of cost‑benefit calculations rely on net present
value; their greater sophistication does not alter the inappropriateness of
present value as a basis for public policy decisions (for an excellent
discussion in the context of forestry in the United States see Overton and
Hunt, 1974).
The
rate at which a population of organisms such as forest trees can be harvested
to give the maximum sustainable return, and the maximum rate at which the
population can be harvested and still sustain itself, can be calculated from a
matrix of birth and death rates by age-group, or from similar matrices for tree
populations using size classes rather than ages (Jeffers, 1978: 52‑62). Matrices have been developed for only a very
few well‑studied species of tropical trees, such as Pentaclethra
macroloba studied by Hartshorn (1975) in Costa Rica. A transition matrix model constructed for
tropical forests in Indonesia, managed under a government‑mandated
system, shows that the system's 35-year harvest cycle is too rapid to sustain
the current yield after the second cycle (Mendonza and Setyarso, 1986).
Management
systems require consistent, long‑term adherence to the harvesting and
other regulations derived from technical studies. Corruption, political changes and other
impediments can easily thwart the best‑laid management plans. In Indonesia, for example, most forest
concessionaires find ways to circumvent the management scheme (Eckholm, 1979:
23). In Nigeria, the political changes
associated with the end of British rule in 1960 led to clearing of much of the
200,000 ha area that was being managed under the tropical shelterwood system
(Lowe, 1977). The CELOS management
system in Surinam was abandoned in 1983 following a coup d'état (de Graaf,
1988).
Government
agencies give virtually universal endorsement to the goal of sustained forest
management, but do not match these ideals through budgetary allocations or
other concrete actions. Private
entrepreneurs have also failed to invest in developing and implanting such
schemes. Logging operators make no
effort to determine sustainable use intensities or to restrict their activities
to such limits. Although frequently
decried as "irrational," this behavior is in fact quite logical under
the current system of economic decision rules.
The
logic of ignoring the harvest limits indicated by calculations of sustainable
yield is most clear in the case of another field of renewable resource
management--fisheries and whaling. In
the case of the Blue Whale, studies of the populations had shown for decades
that the rate at which whales were being harvested would rapidly extinguish the
population. Still, companies continued
to invest in whaling ships in the full knowledge that they would have to sell
them for scrap or convert them to other uses a few years later when the whales
had been exterminated. Short‑term
profitability and rapid write‑off of equipment investment made this
financially attractive. The investment
decisions were not the result of "short‑sightedness," nor of a
lack of scientific knowledge, but rather of cold and competent reasoning based
on an underlying logic that needs to be rethought.
Rapid
discounting of future returns leads to decisions to harvest natural populations
at unsustainable rates, leading to elimination of populations and extinction of
species when the discount rate is more than twice the maximum reproductive
potential of the population (see Clark, 1973a,b, and 1976 for mathematical
proof). The same relationship can be
expressed in terms of a critical point at which it becomes economically
"rational" to invest in unsustainable systems rather than sustainable
ones, while investing the proceeds in other ventures as fast as they come
in. The point is reached when the ratio
of the net profit rate for irresponsible management to the net profit rate for
responsible management becomes greater than or equal to a "golden
number" derived from the available rate of return on alternative
investments and the time that the undertaking could run at a profit if managed
unsustainably (see Fife, 1971 for mathematical proof).1
Common Property
Irresponsible
use of potentially‑renewable natural resources is further encouraged in
many situations by what is known variously as the "common resource
dilemma," the "prisoners' dilemma" and the "tragedy of the
commons" (Hardin, 1968). In cases
such as the exploitation of whales it is "rational" for the
independent nations, firms and individuals involved to harvest the population
as fast as possible rather than to adopt a lower (potentially sustainable)
harvest rate; they knowingly destroy the resource because each perceives that
the others will do so anyway. The same
dilemma applies to logging in public lands carried out by independent firms and
individuals, and to situations where the costs of exploitation are widely
distributed, such as climatic effects of deforestation or social tensions
resulting from concentration of land tenure.
The logic applies even if the total cost to society far outweighs the
total benefits from any given form of land management.
Risk
Applying
NPV is often further flawed by less‑than‑full weight being given to
risk and uncertainties. The lack of
understanding of decision processes is shocking given the importance of the
decisions at stake, including those involving sustainable forest
management. Little has been done to
improve our knowledge of how people arrive at decisions that involve a range of
probabilities of different outcomes and varying degrees of confidence in the
information base available. The field of
decision analysis makes explicit the calculations involved in weighing these
effects, but the fundamental input to the calculation‑‑the
"risk indifference curve" for those making the decisions‑‑is
difficult to quantify and virtually non-existent for the various types of
actors that are now playing major roles in transforming tropical forests to
other uses, both sustainable and unsustainable.
Traditional
farmers, such as Amazonian caboclos, are usually highly risk‑averse
(Raiffa, 1968; Lipton, 1968 cited by Shanin, 1974: 72; Found, 1971: 108). They often behave in ways that aim to
increase their security of obtaining a minimum acceptable harvest, rather than
jumping at opportunities to maximize the expected monetary value of their
undertaking by opting for land use indicated as "rational" by simple
application of linear programming. As
market economies expand in areas of predominantly subsistence‑oriented
decision-making, a rapid increase occurs in the role played by efforts to maximize
profits at the expense of accepting greater risks. In Peru, for example, traditional farmers
were quick to become commercial loggers (with little regard for sustainability)
when transport and marketing opportunities entered the Amazon area (Durham,
1977).
In
areas of pioneer settlement, the mix of different risk‑taking strategies
is extremely varied. While a series of
behavioral buffers protects such colonists from some of the variability in agricultural
success from year to year, many decisions observed can only be described as
gambling‑‑people's acceptance of high risks in the hopes of
obtaining a payoff that would otherwise be beyond their grasp (Fearnside,
1980).
Large
enterprises can afford to take greater risks on individual undertakings than
can small farmers. At the same time,
large firms in general spend a greater proportion of their resources in trying
to secure their long‑term survival than do small ones (Galbraith, 1972;
see Helliwell, 1977). Sustainable
forestry management should be most attractive to large firms since the
principal attraction of this land use is its offer of long range stability
rather than quick profits. The large
areas required to guarantee an adequate harvest rotation also make big
operations most appropriate. It is
important to remember that large management units do not necessarily exclude
individuals with modest resources, as such people could join together in cooperatives
for forest-management purposes given the proper institutional support.
In
terms of research, one of the greatest shortcomings is a better evaluation of
the risks implied by different management schemes. Many of the data essential to rational risk
evaluation are unavailable: such basic data as rainfall measurements spanning
even a few years are often lacking for the locations in question. In a region where rainfall varies greatly
over short distances and from one year to the next, this can be critical
(Fearnside, 1984a). The classic example
of this is Britain's massive groundnut plantation fiasco in Africa in the 1950s‑‑a
scheme based on a mean rainfall adequate for the proposed crop but ignoring the
high variability from year to year.
Variability in rainfall, as well as in other factors affecting
production, is an important factor in limiting human carrying capacity
(Fearnside, 1986c). In addition to the
need for better data on variability, much more work needs to be done on the
means to rationally incorporate such information into planning decisions,
especially when the risks involved go beyond the chance of losing the money
invested.
Development
plans often ignore the unsuitability of physical factors at the target location
even when the data exist (Fearnside, 1986d).
This pattern is frequently explained by such factors as: political
influence of the location chosen; financial rewards to the firms that build the
roads and other infrastructure, or supply goods and services to the
construction activities; and speculative profits to landholders in the areas
served by new roads and programs.
Departures from technically‑ sound plans motivated by factors such
as these can have high financial, environmental and human costs.
FOREST MANAGEMENT IN AMAZONIA
Brazil
At
present, no sustained management system is operating on a commercial scale in
lowland Amazonia. Commercial forestry
practices are reviewed by Palmer (1977) and Rankin (1985). Development of experimental systems is still
incipient when compared with the testing programs in Asia and Africa but
research initiatives are slowly increasing in frequency. Surveys of seedlings and saplings from
natural regeneration in Amazonian forest, and subsequent experimental trials of
forest management systems, first began in 1955 at Curuá‑Una (near
Santarém, Pará) under a bilateral agreement between the Food and Agriculture
Organization of the United Nations (FAO) and the Brazilian government (Pitt,
1961). In 1963, a trial was installed
for testing the Tropical Shelterwood System (TSS) originally developed by the
British in Nigeria (cf. Lowe, 1977). The
system involves cutting climbers and uneconomic saplings and poisoning of some
larger trees of uneconomic species several years before harvesting, followed by
a selective harvest and a removal of climbers and "shelterwood"
several years after the harvest. The
maintenance of "shelterwood," or trees shading the understory, keeps
microclimatic conditions favorable for the tropical hardwoods throughout the
cycle. Early results are summarized by
Dubois (1971); natural regeneration remains encouraging as the first
growth-cycle advances (Rankin, 1979, 1985).
The research program suffered a decade of neglect after the bilateral
agreement terminated in the early 1960s, but was resumed in 1973 under an
agreement between FAO and the Superintendency for Development of Amazonia
(SUDAM). Evaluation of tests with about
15 years of growth, comparing enrichment plantings of seedlings with natural
regeneration of the same age, impressed SUDAM with the better growth and form
of natural regeneration (Pandolfo, 1985).
The great expense of transporting, planting and maintaining significant
numbers of seedlings is also a major factor in favor of systems based on natural
regeneration (Rankin, 1979). The term
"natural regeneration" as used in forestry management schemes of this
type refers to growth of volunteer seedlings and saplings under more‑or‑less
intact forest canopy, not to the growth of secondary vegetation in clearcut
areas that is sometimes euphemistically referred to by the same term.
At the
Tapajós National Forest (FLONA), tests were implanted in 1975 by the Brazilian
Institute for Forestry Development (IBDF) with exploitation at different
intensities (de Carvalho, 1985; GalvÔo, 1985).
Silvicultural treatments to be applied to the plots during the expected
20‑25-year period between harvests have apparently not yet been chosen,
but may include cutting vines, eliminating malformed or otherwise defective
trees of commercial species, and eliminating some non-commercial trees (de
Carvalho, 1985). With three years of
post-harvest growth measurements, the rate of increase in basal area was
greater under lighter (lower limit for harvest = 55cm DBH) than under heavier
(lower limit for harvest = 45cm DBH) exploitation when only commercial species
were considered, but showed the opposite tendency when the comparison was made
for all species (de Carvalho, 1985: 12).
Interpretation of the results is hampered by undocumented exploitation
of the area before the studies began (see Rankin, 1985). Because of the slow rate at which forests
regain natural equilibria, even a light disturbance can prevent subsequent
studies from producing valid results on the effects of management
treatments. Management effects on the
growth of large trees (as opposed to seedlings and saplings) are particularly
difficult to establish under these circumstances; previous disturbance has
prevented establishing such links in studies in Nigeria (Lowe, 1981). The regeneration of seedlings following
selective felling is considered satisfactory in the FLONA experiments (de
Carvalho, 1980, 1984), although data from a full harvesting cycle will be
necessary to confirm the sustainability of the system (Rankin, 1985).
At the Jari project, the Brazilian Enterprise
for Agriculture and Ranching Research (EMBRAPA) and IBDF installed a series of
0.25ha plots in 1983 (GalvÔo, 1985). The
plot design and treatments are the same as those at FLONA, although there are
fewer plots (48 plots at Jari vs. 144 at FLONA). One of the two experimental areas at Jari
(Felipe, Amapá) is undisturbed.
The
National Institute for Research in the Amazon (INPA) has begun a study in its
"model basin" (90 km north of Manaus); growth and recruitment, as
well as hydrological effects, will be monitored under exploitation at different
intensities (Lowe, 1981). Surveys of
seedling stocks (Higuchi et al., 1985) and of short‑term tree
growth (Higuchi, 1987) have been completed in the undisturbed state, but management
treatments have not yet begun.
Florestas
Rio Doce‑‑the forestry sector of the Companhia Vale do Rio Doce
(CVRD) mining company undertaking the Carajás iron project‑‑initiated
a forestry management experiment for charcoal production in 1983 at Buriticupu,
MaranhÔo. The scheme involves removing
the smaller trees (better for making charcoal), together with the understory,
in plots exploited at varying intensities (de Jesus et al., 1986, nd.
(1984); Thibau, 1985, 1986). The
experiments include treatments with clearcutting and with heavy exploitation
that leaves only a few scattered trees in an otherwise clearcut field. In 1985, C.E. Thibau, president of Florestas
Rio Doce and designer of the study, pointed with enthusiasm to the rapid growth
of secondary vegetation in the clearcut and near‑clearcut
treatments. Despite subsequent
disclaimers that clearcutting was included in the experiment merely as a second
control (Renato Moraes de Jesus, public statement, 1988), written presentations
of the experiments use the term "control" exclusively with reference
to undisturbed forest, and present clearcutting as treatment number three of
five treatments (de Jesus et al., 1986: 246). The propriety of considering as
"forestry management" a practice that removes all of the forest is
questionable.
The
Buriticupu forestry management experiments have great potential impact on
deforestation in the region because of legal and semantic questions regarding
"forestry management," plus the tremendous demand for charcoal
implicit in the pig‑iron production schemes being established for the
processing of ore from Carajás (Fearnside, 1986a,b, 1987, 1988; Fearnside and
Rankin, 1982a). Brazil's 1965 Forestry
Code (Decree Law 4771, Article 44) requiring that 50% of any property remain
under natural forest cover has been reinterpreted by IBDF (Normative
Instruction 302 of 3 July 1984) to allow clearing for annual crops or pasture
in 20% of each property and "forestry management" in the remaining
80%. If "forestry management"
is interpreted to include clearcutting followed by leaving the area to
secondary vegetation, even if (at least theoretically) with a view to
subsequent harvests, then the legal obstacles will be removed to rapid
deforestation for charcoal production in private lands and in concessions
granted to firms exploiting Brazil's national forests. A Eucalyptus plantation almost ten
times the area of Jari's silviculture operation would be required to supply the
charcoal for the 20 pig‑iron plants and four other industries planned for
the Carajás region, if yields equal to those at Jari are assumed (Fearnside,
1988). The tremendous expense and
numerous biological problems associated with plantations of this scale make it
likely that native forest will be cut before such investments are undertaken
(see Fearnside and Rankin, 1980, 1982a,b, 1985). Adopting "forestry management" as a
euphemism for clearcutting would speed this process.
In 1984
Florestas Rio Doce replicated the experimental design of Buriticupu at Porto
Trombetas, Pará (de Jesus, nd (1984), de Jesus et al. nd (ca.
1986)). The scheme envisages producing
firewood for drying bauxite ore in the MineraçÔo do Norte (CVRD/ALCAN) mining
concession. Another modification of the
experiments has been installed in part of CVRD's 17,000 ha tract with a view to
charcoal and lumber production (de Jesus and Menandro, nd (ca. 1986)). The much lower cost of obtaining wood from
cutting native forest than from silvicultural plantations provides strong
motivation for tapping this biomass source even though the long‑term
sustainability of production is yet to be demonstrated (Fearnside, 1988).
Surinam
In
Surinam, the Malayan Uniform System was tested in the 1950s. The system, which calls for poisoning virtually
all large trees remaining after a commercial harvest so that the growth of
seedlings and saplings will be stimulated, resulted in an explosion of vines
and undesirable secondary forest species when applied in Surinam (Jonkers and
Schmidt, 1984). Unlike the Southeast
Asian forests, which are dominated by commercially valuable dipterocarps, the
forests of South America are mostly composed of species with low value on
today's markets. Removing the many
non-commercial trees radically increases sunlight reaching the forest floor,
benefitting weedy species.
Since
1967, workers in Surinam have developed another management scheme‑‑the
CELOS Silvicultural System (Boxman et al., 1985; Jonkers and Schmidt,
1984). Following selective logging,
about half of the remaining forest biomass is killed by poisoning
non-commercial trees above a certain diameter limit (35 cm in Surinam) in order
to promote growth of commercial trees that are approaching harvestable
size. A subsequent modification of the
system restricts poisoning to trees within a 10m radius of commercial trees
whose growth is to be favored (Boxman et al., 1985). The system's developers hope for a 40m3/ha
timber harvest every 20 years, although they caution that long‑term
monitoring will be necessary to confirm that productivity will not be reduced
by the drain of nutrients they observed in streams leaving the treated plots
(Jonkers and Schmidt, 1984: 296).
French Guiana
In
1982, testing began in French Guiana of a management system consisting of the
selective harvest at different intensities for timber, firewood or both,
followed by poisoning of non-commercial trees (Bariteau, 1986; Maitre et al.,
1984; Sarrailh and Schmitt, 1984). The
system is based on earlier work in the Ivory Coast, and is similar to the CELOS
system in Surinam. Diameter increases
measured in the undisturbed forest in French Guiana (6.20 mm/year) and in the
first year after treatment (9.50 mm/year) make the researchers optimistic that
the work will lead to an economically viable system of sustained production
(Schmitt, nd (1984)). The researchers in
French Guiana emphasize the similarity of treatment effects to those found in
Surinam, where average diameters in commercial species in selectively‑logged
forest grew at 4 mm/year if untreated and 9‑10 mm/year under the CELOS
system (Jonkers and Schmidt, 1984).
Peru
In
Peru, application of a management plan called the "Protective Strip
System" began in 1982 in the Piches‑Palcazú Project, located in a 20
X 70 km valley in the lower foothills of the Andes at elevations ranging from
270‑500 m (Hartshorn et al., 1985). The system calls for clearcutting strips of
forest 20‑35 m in width following the contour of the valley. Strips cut in successive years would be at
least 200 m apart, and the planned rotation would return to each strip at
intervals of 30 years. A similar system
has been suggested by Jordan (1982, 1985: 154) as a means of speeding
succession in the harvested strips.
While it is far too early to assess the system's sustainability, the
first cycle of harvesting has been profitable and the research team is
enthusiastic about the system's potential for wider application (Hartshorn et
al., 1985, 1986).
Development Policies
The
increasing frequency of research inititatives aimed at developing sustainable
systems for managing Amazonian forest is heartening. However, the funding devoted to research in
this area is minimal in comparison to the importance of the resource at
stake. Rapid deforestation in Amazonia,
especially for unsustainable cattle pastures, means that decision‑makers
are likely to be forced to act on forest management schemes in the absence of
long-term testing. Two such large‑scale
programs have been proposed in Brazil: the "income forests" scheme
put forward by SUDAM (Pandolfo, 1978) and the forest utilization or "risk
contract" scheme of FAO and IBDF (Schmithu"sen, 1978; see Fearnside,
1986c: 33‑34). The management
programs to be applied are vague in both cases: as Mauro Silva Reis, then head
of Brazil's now dissolved Project for Forestry Development and Research
(PRODEPEF), observed: "in truth, a self‑sustained system of
production for the dense tropical forest for industrial ends, based on the
model considered here, has not yet been developed" (Reis, 1978: 14). Neither of these programs has gone forward:
in addition to technical uncertainties there is little commercial interest, the
schemes would require heavy government expenditures, and, in the case of the
"risk contracts" plan, the proposed involvement of foreign timber
firms provoked widespread opposition.
In
1986, the Brazilian Institute for Forestry Development (IBDF) began requiring
the submission of an acceptable "management plan" as a condition for
issuing logging permits. In addition to
the confusion over what constitutes a "management plan," there is a
lack of research results because of the low priority this field has
received. The same economic forces that
explain the absence of commercial sustained management systems in Amazonia
today can be expected to result in entrepreneurs attempting to find ways around
the new regulations. Brazil's informal
system of "jeitos" makes enforcement of such regulations difficult
(Rosenn, 1971). Unless the basis of
economic calculations is changed, the motivation to circumvent the new
"management plan" requirements will be strong.
The
degree to which management interventions should perturb the natural ecosystem
is a matter of much disagreement and presents ample opportunity for Orwellian
doublespeak. "Sustainable
management" and "natural regeneration" conjure up images of an
environmentally-benign tapping of the forest's productive potential without
destroying the existing ecosystem.
However, it is quite possible to "destroy the forest in order to
save it" by going too far along the continuum of increasing management
intensity. For example, poisoning a
large percentage of the trees in the Amazonian forest may maximize commercial
timber yields, but would sever many poorly‑understood ecological pathways
and sacrifice as‑yet unexploited and/or unknown products such as genetic
material and pharmaceutical compounds.
The increasing value and the irreplaceability of many of the potential
benefits of forest use could mean that intervention should be kept below the
intensity indicated by timber management considerations alone. Determining the response of timber production
to different intensities of management and the ecological changes provoked at
each intensity should be urgent priorities.
Rational decisions will also require assessing the many non‑timber
forest products, knowledge of which is rapidly being lost with the
disappearance and acculturation of indigenous tribes.
ALTERNATIVES TO PRESENT CRITERIA
Elsewhere
(Fearnside, 1983), a series of guidelines has been proposed for evaluating 14
classes of land-use options in Amazonia, including sustainable forest
management. Nine criteria were
considered: agronomic sustainability, social sustainability, unsubsidized
economic competitiveness, self‑sufficiency, achievement of social goals,
consistency with maintenance of adjacent areas in other uses, retention of
development options, effects on other resources, and macro‑ecological
effects. Conflicts among these criteria
often highlight fundamental inconsistencies in the goals of development
planners (Fearnside, 1984b). While some
conflicts of interest are unable to be resolved, many divergent needs and
demands can be attended to through a planning strategy aimed at producing a
patchwork of land uses where different environmental and social criteria are
applied (Odum, 1969; see Eden, 1978; Fearnside, 1979; Margalef, 1968).
The
role of net present value as the criterion used in economic decision‑making
at all levels is the root of the current state of affairs where neither
government research and financial agencies nor private enterprises are willing
to invest more than token amounts in the development and application of
sustained- yield forestry systems. While
a satisfactory alternative to this criterion has not yet been developed, some
suggestions might be made as to how to begin.
Projects should be evaluated on the basis of contribution to the
well-being of the present residents of the Amazon region and their
descendants. Benefits must accrue to all
levels of society and future as well as to the present. The limitation of planning to Amazonia's
present residents and their descendants recognizes the region's inability to
offer solutions to the socio‑economic problems of other countries or
regions of Brazil. These are problems
that must be recognized and solved within those other regions‑‑not
postponed by the combination of passing immigrants to Amazonia and removing
marketable products from the region for the benefit of non-residents. Recognizing these limits would allow the
realization of the greatest hope in the region‑‑the possibility of
designing sustainable systems that attend to local needs for centuries to
come. Constraints on development options
should include the limitation of macro‑ecological effects such as
climatic changes, the attainment of a defined distribution of income, and
maintenance of the human population within the bounds of carrying
capacity. Once a decision‑making
framework has been that recognizes the value of human beings in this way has
been devised and adopted, then the choices of forest species and management
techniques will come automatically as the nation's efforts are focussed on
solving the remaining technical barriers to sustainable forest management. Until underlying economic decision processes
are changed, however, no amount of research on management techniques can be
expected to alter what is now the most salient fact about sustained management
of forests in Amazonia: that no one is doing it.
NOTES
(1)
Irresponsible management becomes "rational" when:
ralt.
t
Nirresp. e
‑‑‑‑‑‑‑‑‑‑‑ _
‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑
ralt.
t
Nresp. e ‑ 1
Where: Nirresp. = the rate of return from irresponsible
(unsustainable) management
(dollars per year)
Nresp. = the rate of return from responsible
(sustainable) management
(dollars per year)
ralt. = the rate if interest (dividend) on
available
alternative investments
(dollars per dollar‑year)
t = the time the resource
can be exploited at a
profit under irresponsible
management (years)
e = the base of natural
logarithms (2.l7l28...)
ACKNOWLEDGEMENTS
Companhia
Vale do Rio Doce (CVRD) provided funds to allow participation in the 1st
International Seminar on Management in Tropical Forests, Serra dos Carajás and
SÔo Luis, 28 January ‑ 1 February 1985.
I thank the seminar organizers for permission to publish this paper
adapted from a translation of my presentation (Fearnside, 1989). J.M. Robinson and two anonymous reviewers
made helpful comments on the manuscript.
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