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Segunda parte
(Second part - Deuxième partie)

RESUMENES POR PAIS

(COUNTRY BRIEFS - RESUMES PAR PAYS) (continuar)

BRAZIL

Brazil has continental dimensions: it extends over 8 511 960 km2, 40 degrees longitude (extreme east of state de Paraiba on the Atlantic to extreme west of state of Acre on the border with Peru) and 39 degrees latitude (northern tip of territory of Roraima with the border with Guyana and Venezuela, 5° 15' N, and southern tip of state of Rio Grande do Sul on the Atlantic coast and the border with Uruguay): both dimensions equal approximately 4300 kilometers. The topography is in most parts smooth and 93% of the whole country is below 800 metres. The highest peaks, above 2,500 meters are confined to two regions: the northern border with Venezuela, in the territory of Roraima and the state of Amazonas and the southeast atlantic coast (states of Espirito Santo, Minas Gerais, Rio de Janeiro and São Paulo). Climates are characterized by an annual average temperature from 26°C in the lower Amazon basin to 16°C in the southern region and less on the mountains of the southeastern atlantic coast, and by an annual rainfall of 3,000 mm or more in some parts of the northern region (Colombian border, delta of the Amazon river) to 300 mm in some parts of the “drought polygon” in the northeastern region (in particular states of Rio Grande do Norte, Paraiba, Parnambuco, Alagoas and Sergipe) (30).

1. Present situation

1.1 Natural woody vegetation

1.1.1 Description of the vegetation types

The diversity of vegetation types reflects the large dimensions of the country and the wide range of climatic and ecological conditions. The main types are listed below within the broad classes used in this study. Excellent books should be consulted for a description of the forest vegetation of Brazil, such as (1), (9), the publications by the RADAMBRASIL project ((15) and (43)), (18), “Los Bosques de Sudamerica” by K. Hueck, as well as numerous documents on specific types (e.g. (7), (22) (25) on cerrado types). In appendix 2 the area distribution of the vegetation classes for the Unesco/C.I.T.V. and Hueck maps are given.

Closed broadleaved forests (NHC)

The humid tropical forests of the Amazon region constitute the largest block of closed forests in a given tropical country. The total area has been estimated in this study at some 340 million hectares. They correspond to humid or very humid climates (rainfall more than 1 500 mm), to the lowland and submontane altitudinal levels (less than 2 000 metres approximately) and can be “ombrophilous” or “evergreen”, “seasonal” or not. The number of forest types is large, whatever the criteria used, whether on “terra firme” (dryland) or in the alluvial zones (swamp forests, periodically or permanently inundated forests). For the dryland forests, Hueck, for instance, mentions eight main “regions” (Amazon delta, Peru and Jari, Tocantins and Gurupi, Xingu and Tapajoz, Madeira and Purus, western “Hylaea”, northwestern “Hylaea” (Rio Negro) and the region of Acre, Beni, Mamore and Guaporé). In the alluvial forests it is commonly spoken about “varzea forests” and “igapo forests”, some of these forests being mainly constituted by palms (“miritizal” of Mauritia flexuosa, “jauarizal” of Astrocaryum jaury etc…).

Special mention must be made of the “campinaranas”, “amazonian caatingas”, “caatingas of the Upper Rio Negro”, “humirizal”, “carrasco”, which are less dense and tall than the usual forests on dry land, and which Aubreville proposes to call under the generic term of “thickets and low forests on white sands”. The RADAMBRASIL project identified more than 5 million ha of these stands (44).

A differentiation is often made (e.g. (44)) between the “ombrophilous dense forest” (“densa”) and the “ombrophilous open forest” (“aberta”), which does not correspond to the division between open (woodlands) and closed (forests) as used in many vegetation classifications. The “ombrophilous open forests”, with or without palm trees (“cocal” or “cipoal”), or “liana forests” are composed of trees more distant than in the case of typical closed forests with a dense scrub storey and correspond mainly to adverse edaphic conditions or limit climatic conditions (transition between the amazonian forests and the cerrado and caatinga areas).

Considerable areas of humid forests with the palm tree known as “babaçu” (Orbignya speciosa) exist in the state of Maranhào, east of Belem. They correspond probably to a secondary facies of the original humid forests after clearing of most tree vegetation except the babaçu trees traditionally used for their oil seeds (1). Some specialists (Sampaio, Hueck) have made a special class in their phytogeographical classification for this type of stands.

Dry semi-deciduous forests can be found in the middle of the amazonian humid forests (called “floresta estacional semidecidual” by RADAMBRASIL). Dry semi-deciduous (and deciduous) forests exist also, generally in degraded form, in the transition zone between the humid forests with babaçu and the caatinga region of the northeast.

The humid evergreen forests of the Atlantic coast, the climax zone of which stretches from Natal (6°S) to the parallel 30°S on a 100–200 km wide band, remains only on the ridges and their total extension does not exceed 3 million hectares. In the south there is a transition zone with coniferous stands of Araucaria and Podocarpus.

Semi-deciduous and deciduous forests are found in patches within the cerrado area and on its southern fringe down to the Paraguayan border, often in contact or mixture with the dense wooded savannas (“cerradãos”).

In the northeastern zone, a small proportion of the caatinga appears as dense forest (classified on the Unesco/C.I.T.V. map as “sclerophyllous dominated extremely xeromorphic forest”) among many other open tree or scrub vegetation types.

Mangroves extend along the Atlantic coast for the border with French Guyana to Florianapolis in the southern state of Santa Catarina (28°S) where scrub trees of Laguncularia recemosa (“mangue-branco”) can still be found. The two main other species are Rhizophora mangle (“mangue vermelho”) and Avicennia nitida (“manguesiriúba”). Within the area already mapped by RADAMBRASIL, (coasts of state of Amapa, Para, Maranháo and Piaui), almost 1.3 million ha of mangrove forest were identified, while the Unesco/C.I.T.V. map indicates for the whole of Brazil an area approximately equal to 3.6 million ha. Comparison with other maps show however that mangrove stands do not exceed a total area of 2,500,000 ha (forests and scrubs).

Open broadleaved forests (NHc/NHO)

(a) The “cerrado” region extends to more than 170 million ha (28) on the south amazonian forests from the territory of Rondonia in the west to that of Piaui in the east where it comes in contact with the caatinga region and down to the northern part of the state of São Paulo. Although some are fairly dense, they are classified here as “open hardwood forests” as they have always a gramineous grass layer which make them sensitive to degradation by fires and they can therefore be compared to the african savannas. The following types are generally differentiated, although there exists a “continuum” of facies:

In (22) some quantitative characteristics are given for four types of cerrado from samples in an area of 10 million ha within the state of Minas Gerais:

Cerrado types CerradoCampo
Stand CaracteristicsCerradão“typical”open
(“ralo”)
Cerrado
Number of stands inventoried7987
Average tree number/ha
(DBH≥5 cm)
1092879616273
Average tree diameter
(DBH≥5 cm)
12.1 cm11.2cm10.1 cm8.9cm
Basal area/ha16.5 m210.2 m26.1 m22.1 m2
Crown cover110%70%45%16%

In most parts of the cerrado area, the stands are used principally for fuelwood and in the states of Minas Gerais and São Paulo they have been exploited for decades for the supply of charcoal to the iron industry. Around 10 million cm3 of charcoal are made every year from the cerrado stands corresponding approximately to an area of 200,000 ha If one considers that fires and grazing are also taking place in many parts of the cerrado area, one can realise the heavy pressure on these stands which will avoid depletion and degradation only if conservatively managed.

(b) Other types of open woodlands exist in various parts of the country. The most important are:

Coniferous forests (NS)

The extent of the Araucaria angustifolia stands (“pinheiro do Parana”) was originally of some 16–17 million hectares, half approximately in the state of Parana 20–25% in each of the states of Santa Catarina and Rio Grande do Sul and the rest in scattered patches in the states of São Paulo and Minas Gerais. Heavy exploitation and clearing for agriculture have considerably reduced these areas over the last fifty years (see paragraph 2.1.1). These forests which are found above 500 metres on the plateaus lowering from the littoral mountains to the rio Parana, have often three storeys (1): a dominant pure stand of Araucaria (20–25 m high), a dominated storey of Podocarpus species or “Pinheiro bravo” (P. sellovii, P. lambertii) and some hardwood species (such as Phoebe porosa, Ilex paraguayensis or ervamate), and a thick undergrowth. Pure stands of Podocarpus are found in the bottoms of the valleys.

Scrub formations (nH)

The phytogeographic region called Caatinga which covers more than 80 million ha principally in the states of Piaui, Ceara, Rio Grande do Norte, Paraiba, Pernambuco, Alagoas, Sergipe and Bahia, constitutes an extremely complex mixture of woody vegetation types with varying degrees of alteration and degradation by man (agriculture, grazing, fuel-wood collection, fires), and of transition with the cerrado types to the west and the south and with the atlantic forest to the east. All cover types of varying heights and densities exist from patches of the original dry forest (“sclerophyllous dominated extremely xeromorphic forest” according to Unesco/C.I.T.V. classification) to poor scrubland with scattered shrubs and cactaceaes, through thickets of varying heights. Area statistics cannot be more than rough estimates until at least mapping by RADAMBRASIL is completed. 30% approximately of the caatinga area was mapped at the time of this study and approximations had to be made from small-scale maps for the rest of the caatinga. However, most of the vegetation corresponds to scrub and thicket types at various degradation stages.

Other scrub types exist in:

1.1.2 Present situation of the woody vegetation

Present areas

Apart from documents providing some global statistics on Brasilian forest resources (e.g. (32) (33)) two main sources of information have been used for estimating forest areas:

Taking into account present deforestation figures for these two halves of Brazil (see paragraph 2.1.1), the two sets of area figures were updated to end 1980 and then added.

The area figures as at end 1971 for the “northern zone” (covered by RADAMBRASIL maps at time of the study) are as follows:

Northern zone” (in thousand ha - total area = 455,775,000 ha)

 of whichNHCaNHc/NHO1NHc/NHO2NHc/NHOnHC/nHO1nHC/nHO2nHC/nHOother landWaters
NHCfNHCf2i
33661041790262403420025200594003,7009,72013420106709435

The following remarks are necessary:

The area figures for broadleaved types of the “southern zone” (not covered by RADAMBRASIL at time of the study), as at mid-'73 approximately, are as follows:

Southern zone” (in thousand ha - total area = 395,421,000 has)

 of which:NHCaNHc/NHO1NHc/NHO2NHc/NHOnH1nH2nHOther land 1Waters
NHCfNHCf2i
30680122701746090,570669501575201418037330515101358712380

1 including coniferous forests (NS)

Some remarks are necessary:

Figures have then been updated to end 1980 for both regions and summed up for the whole country. The following table shows also the areas of closed forests reserved for non-productive purposes (NHf2r) estimated from the descriptive lists of national parks and biological reserves ((30) (36) (40) and more recent documents).

Areas of natural woody vegetation for whole of Brazil estimated at end 1980

(in thousand ha - Total country area = 851,196,000 ha)

  NHCf1NHCf2iNHCf2r1NHCf2NHCfNHCa
ClosedNorth2860604134043504569033175027420
hardwoodSouth14570966030099602453019000
forestsBrazil3006305100046505565035628046420
Coniferous forestsNSf1NSf2iNSf2rNSf2NSfNSa
280910109201200 
Woodlands and scrublandsNHc/NHO1NHc/NHO2NHc/NHOnH1nH2nH
11715094050211200227003850061200

1 Part of the forest reserved for non-productive purposes (NHCf2r) are also unproductive for physical reasons. The actual total of forest areas unproductive for physical reasons is therefore a little higher than that indicated for NHCf2i.

The rest of the country is constituted mostly by agriculture and grazing areas. The extent estimated is approximately half the official figure of 322,621,000 ha indicated for agricultural and grazing lands in 1975 (28). The difference can be explained by various factors. One main obvious reason is that new and old agricultural fields exist within the class NHCa and part of the classes NHc/NHO2 and nH2, since these classes include also mixtures of agriculture, and secondary vegetation. Many grazing areas exist in natural woodlands and scrublands (NHc/NHO and nH). It may be also that a certain number of agricultural and ranch estates are still covered partly with natural vegetation.

1 This is in fact an average time. The radar surveying for most of this area was subcontracted by instalments, from March 1971 to June 1972 (43).

Ownership

The document (3) divides the 379 million ha of forests in 1950 between forests “not in use” (323 million ha corresponding essentially to the Amazonian region and being the public domain of the states, mainly Amazonas and Para) and 56 million ha of “forests in use” with the following breakdown of ownership:

Type of ownershipAreas
('000 ha)%
Public ownership  4280  7.6
Private ownership(51720)(92.4)
Association  959417.1
Company  3127  5.6
Individual3890469.5
Other      95  0.2
Total forest area considered56000100.0  

The following which corresponds to the situation as at 1950 is extracted from the same publication:

“The forests in use are generally part of agricultural enterprises, which often are in the form of large latifundia properties, especially near the coast. As the size of holding becomes greater, the proportion of forested land increases. A number of pulp, mining, and railroad companies own extensive tracts of forest to assure themselves of at least part of their supply of pulpwood, charcoal, and fuelwood. One pulp company, for instance, owns more than 400,000 acres of forest, much of it Paraná pine, and other land in the State of Paraná.

As in the United States, there are a large number of small ownerships of under 250 acres of all types of land, their average area in forest being less than 10 acres. More than 200,000 land units, two-thirds of them in public ownership, are occupied by squatters.”

The ownership of “forest lands” given for 1973 in document (33) is as follows:

RegionsPublic ownershipPrivate ownership 
('000 ha)% of forests of the region('000 ha)% of forests of the regionTotal
('000 ha)
North29834493.1222016.9320545
Northeast6301587.0945013.072456
West central5089971.02081229.071711
Southeast1685874.0593226.022790
South188928.6471071.46599
Total43100587.26310512.8494110

Although there is no clear correspondence between the vegetation types and the forest lands (we shall assume that all closed forests are included, plus the largest part of wooded savannas and some caatinga stands), the above table gives some interesting indications:

Legal status and management

13 “National Forests” covering 853,000 ha have been created since 1946 as permanent forest reserves for the production of raw material for wood processing industries. Two forests (Caxinanã and Tapajos) cover a total of 800,000 hectares in the state of Para and ten small ones cover a total area of 18,000 hectares in the southern and southeastern regions in which plantations are being carried out.

In 1980, 21 national parks and 9 biological reserves covering respectively 5,263,000 ha and 796,000 ha had been created “for safeguarding exceptional attribute of nature, while conciling integral protection of the flora, the fauna and natural beauties with the utilization for educational, recreational and scientific objectives” (Brasilian forestry law no. 4771/65). The largest ones, Parque Nacional Pico da Neblina (2,200,000 ha), Parque Nacional de Amazonia (1,000,000 ha) and Parque Nacional de Pacaas Novos (765,000 ha), are located entirely in the Amazonian region. Total dense forest area covered by all parks and biological reserves is estimated at 4,650,000 hectares (=NHCf2r) plus some 10,000 hectares of Araucaria stands (=NSf2r). Most of the national parks and biological reserves are situated in the southeastern and southern states and the first were created already before World War II (Itataia and Serra dos Orgãos in the state of Rio de Janeiro, and Itaipa in Paraná state).

It can be said that there is not at present intensive forest management on significant areas, although attempts are made to develop sustained management of amazonian forests (Tapajós).

Forest utilization

• Log harvesting

The 1977 edition of the FAO Yearbook of Forest Products give the following production data (in million m3):

 Year1961–65 average666768697071727374757674–76 average
Category 
BroadleavedTimber
(sawlogs + veneer logs)
6.35.96.36.67.07.5  7.8  7.0  7.8  8.6  10.212.210.3
Pulpwood1.01.51.61.71.92.1*2.3*2.4*2.4*2.4*3.74.23.5
Total7.37.48.98.38.99.6*10.1*9.4*10.2*11.0*13.916.413.8
ConiferousTimber5.96.47.27.98.49.3  9.4  9.1  8.2  8.2*11.011.710.3
Pulpwood0.71.01.01.11.21.4*1.5*1.6*1.6*1.6*1.61.71.6
Total6.67.48.29.09.610.7*10.9*10.7*9.8*9.8*12.613.411.9
Broadleaved and coniferousTimber12.212.313.514.515.416.8  17.2  16.1  16.0  16.8*21.223.920.6
Pulpwood1.72.52.62.83.13.5*3.8*4.0*4.0*4.0*5.35.95.1
Total13.914.816.117.318.520.3*21.0*20.1*20.0*20.8*26.629.825.7

* FAO estimates

This table shows a steady increase of production of raw material for wood-processing industries resulting in a doubling of the yearly production from 1961–65 to 1974–76. The share of the total annual production between natural forests and plantations during the period 1974–76 is estimated as follows (see also (33)):

 Natural ForestsPlantationsTotal
(million m3)(%)(million m3)(%)(million m3)
Broadleaved10.072%3.828%13.8
Coniferous    9.9 183%2.017%11.9
Broadleaved + Coniferous
19.977%5.823%25.7

1 Probably overestimated

In first approximation it can be said that natural forests as far as raw material for wood processing industries are producing wood for the mecanical industries, while plantations produce essentially pulpwood.

In hardwood forests, in particular in the Amazon basin, logging is highly selective and extracts at a time between 2 and 10 m3 of logs of a limited number of species per hectare. In many cases it is carried out with very simple equipment on the most accessible areas with respect to topography and access to roads and rivers. The Amazon forests account for less than 4 million m3 of hardwood logs.

Exploitation of the coniferous forests of the southern states has been developing too rapidly in relation with the productive capacity of these forests, which are over-exploited, generally before giving way to agriculture. Around 50 m3 are extracted per hectare in the remaining undisturbed forests of Araucaria.

Other forest products

• Charcoal

Brazil is an important producer and consumer of charcoal for its pig iron industry (20) (22) (33) and (46). It is made principally from the exploitation of the cerrado woodlands of the state of Minas Gerais although eucalypt plantations are providing an increasing part of the raw material (see paragraph 1.2.2). In 1971 8 million m3 of wood were exploited for charcoal 1 corresponding to an area of 160,000 ha of cerrado (or 50 m3/ha) (22). In 1975 the production was 3,575,000 ton of pig iron corresponding to 13 million m3 of charcoal or 23.5 million m3 of wood (33). The demand of raw material for charcoal from the cerrado of the states of the southeastern region (Minas Gerais, São Paulo, Espirito Santo and Rio de Janeiro) is expected to increase up to 21 million m3 in 1980 and then decrease to 5 million by year 2000 (33).

1 1 m3 of roundwood gives 0.56 m3 of charcoal which is needed to produce 0.15 – 0.16 ton of pig iron (33).

The following table (33) projects distribution of demand of wood for charcoal from the various sources during 1975 – 2000.

(in million m3)

YearsFrom plantations 1From closed forestsFrom cerrado
southeastwest central
1975  -717  -
198011621  -
198518515  -
2000232  529

1 In 1974 10% of charcoal already came from eucalypt plantations (20).

• Fuelwood

The following figures of consumption of fuelwood per region for 1975 and projection for 1980, 1985 and 2000 are extracted from (33):

(in million m3)

YearsNorthNortheastWest CentralSoutheastSouthBrazil
Totalper capita
(m3)
19755.647.3  7.937.619.8118.21.01
19805.746.5  8.937.519.9118.50.89
19855.843.510.238.820.8119.10.80
20005.936.214.943.223.1123.30.60

No substantial increase is foreseen except in West Central Region (states of Mato Grosso and Goias covered mostly by cerrado vegetation types) and a decrease is contemplated in northeastern region where the caatinga vegetation types dominate.

However the forecasts provided in the above table have to be corrected to take into account the wood alcohol programme which the government intends to set up to reduce the country's dependence on imported fuel.

• Other industrial roundwood

According to the FAO definition this category includes “roundwood used for tanning, distillation, match blocks, gazogenes, poles, piling, posts”. Some estimates and projections of demand for these products are given in document (33) which are reproduced on the following page:

(in million m3)

YearsNorthNortheastWest CentralSoutheastSouthBrazil
19750.120.620.201.800.663.40
19800.150.850.272.170.814.25
19850.180.990.352.310.924.75
20000.311.530.742.711.386.67

• Other forest products

The following table summarizes information on the main vegetal extracts produced and processed in Brazil (28) (9) (3) (24).

List of main vegetal products of Brasil

Type of product and local nameLatin nameType of plantRegionUsesAverage annual production (tons)
1955–611973–74
FibersBatia  
Northeast-Western Bahia
 35793374
CaroáNeoglaziovia variegata "fibres for coffee sack & substitute for jute 65
Guaxima (aramina)Urena lobatapalm shrubBahia-Minas Gerais" 6020
MalvaSida spp.        ""cottonlike fibre (in capsules of fruits)16440 
Kapok
Chorisia insignis - Ceiba pentandra
trees?? 208
Painas?        ? 
fibre for brushes and brooms
1413350704
PaisavaLeopoldinia piassavapalm tree
Northeast-Western Bahia
fibre for fishing lines and nets
  
TucumBactris spp. Astrocaryum spp.        "" 6986
        
Gums and resins
BalataManilkara bidentatatreeAmazon forestelectrical insulation779338
Coquirana (ucuquirana)Ecclinusa balata    ""        "         "282156
MaçarandubaManilkara huberi    ""        "         "779667
SôrvaCouma utilis    ""chewing gum-chalking material for boats15903295
        
OleaginousAndirobaCarapa guianensistreeAmazon iguapos and varzeasOleaginous seeds??
BabaçuOrbignya martianapalm treeNorth & Mato GrossoOleaginous almonds91942219146
Licuri (curicuri)Syagrus coronata        "
Northeast-Western Bahia
Oleaginous seeds for soap and margarine42848009
MurumuruAstrocaryum murumurumsmall palmPara        "         "1284102
OiticicaLicania rigidatree
Northeast-Western Bahia
Oleaginous seeds3085850970
McubaVirola spp.treeAmazon Iguapos and varzeas"??
TucumBactris spp. -Astrocaryum spp. 
Northeast-Western Bahia
Oleaginous seeds for soap and margarine45278945
        
RubbersCauchoCastillea uileitreeAmazon forestsElastic rubbers255129
HeveaHevea spp.tree""3085226002
MangabeiraHancornia speciocasmall treeGoias"5219
ManiçobaManihot glazioniishrubNortheast (Ceara)"3152
        
Tanning extracts
AngicoPiptadenia spp.tree shrubSoutheast-SouthTanain (from bark)228335666
BarbatimãoAcacia decurrenstreeSouth"?5954
MangueRhizophora spp.    "Littoral"?1062
QuebrachoSchinopsis spp.    "Chaco (south of Mato Grosso)"??
        
MaxesCarnaubaCopernicia ceriferapalm tree
Northeast-Western Bahia
Max (from leaves)910719296
Licuri (curicuri)Syagrus coronata        """388123
        
Food productsCastanha de cajuAnacardium occidentale (cajú)small treedry areas of Amazon forestsCashew nuts437935918
Custanha-do-paráBertholletia excelsatreebrazil nuts3799143885
Eroa-mateIlex paraguaiensissmall treeSouth-south of Mato Grossotea-like drink9433995162
Guaraná   nuts?130
PalmitoEuterpe oloraceapalm treeAmazon forestspalm hearts?35430
        
Essential oils and medicines
CopaibaCopaifera spp.small treeAmazonas, Para, Mato GrossoPerfumes-medical uses60?
Ipecacuanha (poaia)   Medicinal uses (root)?27
Pau rosaAniba spp.treeAmazon forestsRosewood essence350?
SassafrasOcotea preciosa    " Sassafras oils384?
Tumbó   Medicinal uses (root)?21
EucalyptusEucalyptus spp.    "South-southeastEssential oil48?

1.1.3 Present situation of the growing stock

Closed broadleaved forests (NHC)

Several small-scale forest inventories and extensive reconnaissance surveys have been carried out in the Amazonian closed forests (lists given in documents (35) and (47)). Sample plots have been enumerated by the RADAMBRASIL project over the whole area mapped and results compiled for this study in document (50). Some figures are also available for the non-amazonian closed broadleaved forests (e.g. (12)) summarized in document (33). For overall estimates of the total growing stock, information is therefore available, although corrections have to be made taking into account different minimum diameters at breast height.

NHCForest area covered
(in thousand ha)
minimum DBH
(cm)
Volume/ha
(m3/ha)
Source
Amazonian forests
(~ “North”)
  10.059 “dryland forest”25185(4) (19) (35)
185.920 “Floresta densa tropical”30  123.5 
  76.581 “Floresta abierta tropical”"      96.9 
    1.935 “Floresta estacional”"      92.0(50)
    9.441 “Campinarana”"      97.8 
  24.339 “Contato” de florestas"    102.5 
    6.536 “Contato floresta - savana”"      98.2 
304.752 (Total)30   113.6 
 25 175(33)
      159 dryland forests (Tapajos)45 175(37)
Non-amazonian closed broadleaved forests
(~ “South”)
Northeastern region25 135 
West central region"   165 
Southeastern region"   130(33)
Southern region"   145 
 25 150 

Obviously the figure provided by document (33) is derived mainly from forest inventory documents first summarized in document (4). However, their (relatively) limited coverage prevent from applying the corresponding figures to the whole of the amazonian forests. In particular poorly stocked forest types like “floresta aberta tropical” and “campinaranas” are not - or not to the same extent - included in the 10 million hectares of “dryland forest” of documents (4) (19) and (35). Differences in volume estimation procedures explain also a large part of these discrepancies. The RADAMBRASIL figures will be used for the Amazonian forests, taking into account their representativeness and the overall average of 155 m3/ha of VOB (volume o.b. of the boles of all trees more than 10 cm DBH) will be used corresponding to a factor of 1.40 between volume o.b. more than 10 cm DBH and volume o.b. more than 30 cm DBH. This is intermediate between figures found for amazonian forests of some andean countries (e.g. Colombia, Bolivia) and higher figures found for Venezuela, Guyana, Surinam and French Guiana.

In the absence of other global figures for the non-amazonian closed hardwood forests, the average figure of 195 m3/ha will be used, corresponding to an average volume of 150 m3/ha for trees above 25 cm DBH (ratio vol. (o.b.>10 cm DBH)/vol.(o.b.>25 cm DBH)= 1.30).

For closed broadleaved forests already exploited (NHCf1uc) the figures will be 145 m3/ha and 175 m3/ha for amazonian forests and non-amazonian forests respectively (5 m3 and 10 m3 are supposed to be extracted per hectare in the form of merchantable logs - “volume actually commercialized” or VAC - for these two types of forests, which, multiplied by 2 (to take into account logging losses and the relation to gross standing volume) correspond to the reduction to be made from gross volumes of undisturbed forests).

As for unproductive closed broadleaved forests (mostly for edaphic or topographic reasons) - NHCf2 - volumes per ha are estimated conservatively at half those of the corresponding productive broadleaved forests, i.e. 80 m3/ha for Amazonian forests and 95 m3/ha for non-amazonian forests.


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