**2.1 Savanna (Cerrado)**

Cerrado is an important Brazilian biome present in the central area of Brazil (Figure 1), formed by a high number of endemic flora and fauna species, and considered a world biodiversity hotspot. According to IBAMA (2010), the biome presents more than 10,000

of environmental impacts during exploration; preservation of areas not economically productive; adequacy to local productive capacity by the quantification of present available stock; reduction of costs and rise of income; achievement of continued production; market expansion through forest certification; compliance of current laws; creation of employment opportunities and most importantly to legalize the activity. Forest management can be understood as the administration of a forest resource by a set of principals, techniques and norms. Its objective is to organize the actions necessary to determine production factors and to control its efficiency and productivity in order to reach pre determined objectives. According to Blaser et al. (2011) in International Tropical Timber Organization (ITTO) Brazil has presented great advance in the sustainable management of natural forests, expanding the areas subject to these practices as have other countries such as Peru, Malaysia, Gabon and Guiana. A few explications that account for this expansion are: enhancement of technologies used for forest monitoring; improvement of administration systems; forest certification and stricter

Amaral and Neto (2005) comment that sustainable forest management has conquered increasing space as an alternative for Latin Americas' rural communities, driven by governments, donors, NGOs and community organizations. According to the authors, the main problems encountered in the implementation of forest management in the Amazon are: (a) establishment of mechanisms for land regularization; (b) strengthening of local social organization; (c) credit access; (d) forestry technical assistance and (e) the need for market access mechanisms. These problems can easily be extrapolated to the other physiognomies

Law 11.284/2006 drafted by the Brazilian Government regulates forests management in public areas; creates the Brazilian Forest Service (SFB) as the regulator agency of public forest management and at the same time the promoter of forestry development; creates the National Forest Development Fund to promote technological development, technical assistance and incentives for the development of the forestry sector. The law also defines three types of management: (a) Conservation units for forestry production; (b) Community Use and (c) Paid forest concessions in Conservation Units of Sustainable Use and in public

A sustainable cutting plan is only feasible when it respects the time needed to close the exploration cycle, i.e. the time it takes the forest to grow biomass to equal before harvest levels. The amount of biomass required determines the duration of the cycle, since it depends on the forest growth rate. Thus, an increased growth rate through silvicultural treatments promotes shorter cutting cycles, and consequently a lower demand of forest area, reducing impacts on other forest areas. For example, the cutting cycle (polycyclic) in the Amazon can be 30 years long considering a selective exploration of marketable species, removing a maximum of 30 m3/ha (IBAMA, 2007), which could represents up to 5 trees/ha (Putz et al., 2008). The determination of the cycle duration depends on the forest type and its

Cerrado is an important Brazilian biome present in the central area of Brazil (Figure 1), formed by a high number of endemic flora and fauna species, and considered a world biodiversity hotspot. According to IBAMA (2010), the biome presents more than 10,000

growth rate (Braz, 2010), this information is presented in the Brazilian legislation.

demands from consumer markets concerning timber origin.

forests. Forest concession in Brazil is still a new experience.

besides the Amazon in Brazil.

**2. Case studies** 

**2.1 Savanna (Cerrado)** 

species of plants, 837 species of birds, 67 genera of mammals, 150 species of amphibians and 120 reptile species, of which 45 are endemic.

It is estimated that the Cerrado biome occupies an area of 203 million hectares, with about 66.4 million hectares remaining, with a population of 29 million inhabitants (SFB, 2010). The vast majority of the population lives in urban areas, the other fraction in rural areas, whose main activity is agriculture (soy, rice, wheat and livestock). Reforestations of *Eucalyptus* spp. can be found, intended for the production of coal, pulp, sawn wood among other uses.

The Brazilian Cerrado's colonization process was stimulated by the government, starting from the 60's, where the development of intensive agriculture, mineral production and extraction of native vegetation was encouraged. This process was made possible by the construction of new highways. During this period, the Cerrado became target of deforestations and fires, being gradually replaced for other uses, and in more extreme cases, areas were abandoned after intense degradation. For example from 2002 to 2008 the deforestation area was 85,074 km2 (SFB, 2010).

Fig. 1. Spatial distribution of the Cerrado biome in Brazil (IBGE, 2004).

Despite the great interest in the use of these environments for farming, Cerrado's soil has high acidity (aluminum saturation) and low chemical fertility (phosphorus, potassium, calcium and magnesium), with average annual rainfall of 1500 mm (ranging from 750 mm to 2000 mm) and of concentrated nature. The average annual temperature fluctuates between 21ºC to 25 ºC. However, due to its flat topography, its lands became valuable since low

Sustainable Forest Management of Native Vegetation Remnants in Brazil 81

The vegetation's structure and size are determined by variations in soil type, climate, altitude, hydrology, anthropic actions and natural impacts such as forest fires. As a result the vegetation presents physiognomies varying from forest formations to grasslands. The forest formations are represented by the Cerradão (dense wooded savanna), Mata seca (semi-arid savanna) and Mata ciliar (riparian forest). The intermediate formations are predominantly Cerrado *Sensu Stricto* (wooded savanna), Veredas, Palmeiral (Palm forests) and Parque Cerrado (parkland). The grassland formations are composed of campo sujo, campo limpo (shrub savannas) and campo rupestre (rupestrian fields). These vegetation types are listed in the same order of biomass reduction. An illustrative example of the existing variations can be seen in Figure 2 and Table 1 presents a quantitative overview of stand characteristics for different Cerrado types. According to Scolforo et al. (2008a), the following species can be classified as the most recurrent in the Minas Gerais cerrado biome: *Astronium fraxinifolium* Schott ex Spreng.; *Caryocar brasiliense* Cambess.; *Copaifera langsdorffii* 

Desf.; *Qualea grandiflora* Mart.; *Qualea multiflora* Mart. and *Roupala montana* Aubl.

to the maintenance of the biome.

Stand characteristics

**2.1.1 Sustainable forest management of the Cerrado** 

development of technologies to replace native wood consumption.

Due to the structural characteristics of native Cerrado trees, timber production is basically converted into charcoal, whose purpose is to supply steel and construction companies in an indirect way. According to statistics of the forestry sector, approximately 50% of the charcoal used in the Brazilian market comes from native areas, where a fraction of the production is the result of illegal deforestation. In the 80's the amount of charcoal from native areas was 85% (AMS, 2007). According to the Brazilian Silviculture Society - SBS (2008), in 2007 the Brazilian charcoal consumption of native origin was 11.88 million tons. On the other hand, the multiple use of the Cerrado can be stimulated, in view of the possibility of production of resins, barks, seeds, flowers, fruits and handicrafts, contributing

> shrub savannas

Number of areas inventoried 5.0 57.0 5.0 Quadratic mean diameter (cm) 11.2 10.2 12.0 Mean height (m) 4.3 5.1 7.4 Average tree number (N/ha) 370.4 1168.9 1626.8 Basal area (m2/ha) 3.5 9.4 18.3 Aboveground wood volume (m3/ha) 17.7 48.5 129.0 Aboveground carbon stock (t/ha) 5.0 14.3 35.1 Table 1. Stand characteristics for different cerrado types in Minas Gerais State, where the data is provided for trees with DBH greater or equal to 5cm (Scolforo et al., 2008a).

In recent decades Brazil has structured and regulated the forestry sector, with the primary purpose of supplying the country's domestic needs, and subsequently the foreign market. This period was marked by government tax incentives and stimulus to reforestation. Strategic planning allowed for market advancement and expansion, driving the

Cerrado types

Wooded savanna

Dense wooded savanna

water deficits in dry periods and low fertility can be controlled through modern technology. The biome's zone of occupation presents an intense river network, which contributes to the formation of the main Brazilian rivers, such as the São Francisco, Amazon, Tocantins, Paraná and Paraguay rivers. The water produced is used for human consumption, industrial ends, agricultural and electric power generation.

The Cerrado interacts with other types of Brazilian biomes, such as the Amazon rainforest, Atlantic forest, the Pantanal and Caatinga, creating diverse ecotones. However, the Cerrado has unique and peculiar features. In general terms it can be considered a transition between forests and grasslands, presenting gradual reductions in biomass and arboreal/shrub density in the landscape, possessing plants with deep root systems as a survival strategy in times of drought. In addition, it features a grass cover that receives a high intensity of light, depending on the arboreal/shrub density of each location.

Fig. 2. Examples of the variation amongst physiognomic types existent in the Cerrado in relation to tree size and density.

water deficits in dry periods and low fertility can be controlled through modern technology. The biome's zone of occupation presents an intense river network, which contributes to the formation of the main Brazilian rivers, such as the São Francisco, Amazon, Tocantins, Paraná and Paraguay rivers. The water produced is used for human consumption, industrial

The Cerrado interacts with other types of Brazilian biomes, such as the Amazon rainforest, Atlantic forest, the Pantanal and Caatinga, creating diverse ecotones. However, the Cerrado has unique and peculiar features. In general terms it can be considered a transition between forests and grasslands, presenting gradual reductions in biomass and arboreal/shrub density in the landscape, possessing plants with deep root systems as a survival strategy in times of drought. In addition, it features a grass cover that receives a high intensity of light,

Panoramic view

Fig. 2. Examples of the variation amongst physiognomic types existent in the Cerrado in

ends, agricultural and electric power generation.

shrub savannas wooded savanna dense wooded savanna

relation to tree size and density.

depending on the arboreal/shrub density of each location.

The vegetation's structure and size are determined by variations in soil type, climate, altitude, hydrology, anthropic actions and natural impacts such as forest fires. As a result the vegetation presents physiognomies varying from forest formations to grasslands. The forest formations are represented by the Cerradão (dense wooded savanna), Mata seca (semi-arid savanna) and Mata ciliar (riparian forest). The intermediate formations are predominantly Cerrado *Sensu Stricto* (wooded savanna), Veredas, Palmeiral (Palm forests) and Parque Cerrado (parkland). The grassland formations are composed of campo sujo, campo limpo (shrub savannas) and campo rupestre (rupestrian fields). These vegetation types are listed in the same order of biomass reduction. An illustrative example of the existing variations can be seen in Figure 2 and Table 1 presents a quantitative overview of stand characteristics for different Cerrado types. According to Scolforo et al. (2008a), the following species can be classified as the most recurrent in the Minas Gerais cerrado biome: *Astronium fraxinifolium* Schott ex Spreng.; *Caryocar brasiliense* Cambess.; *Copaifera langsdorffii*  Desf.; *Qualea grandiflora* Mart.; *Qualea multiflora* Mart. and *Roupala montana* Aubl.

Due to the structural characteristics of native Cerrado trees, timber production is basically converted into charcoal, whose purpose is to supply steel and construction companies in an indirect way. According to statistics of the forestry sector, approximately 50% of the charcoal used in the Brazilian market comes from native areas, where a fraction of the production is the result of illegal deforestation. In the 80's the amount of charcoal from native areas was 85% (AMS, 2007). According to the Brazilian Silviculture Society - SBS (2008), in 2007 the Brazilian charcoal consumption of native origin was 11.88 million tons. On the other hand, the multiple use of the Cerrado can be stimulated, in view of the possibility of production of resins, barks, seeds, flowers, fruits and handicrafts, contributing to the maintenance of the biome.


Table 1. Stand characteristics for different cerrado types in Minas Gerais State, where the data is provided for trees with DBH greater or equal to 5cm (Scolforo et al., 2008a).

## **2.1.1 Sustainable forest management of the Cerrado**

In recent decades Brazil has structured and regulated the forestry sector, with the primary purpose of supplying the country's domestic needs, and subsequently the foreign market. This period was marked by government tax incentives and stimulus to reforestation. Strategic planning allowed for market advancement and expansion, driving the development of technologies to replace native wood consumption.

Sustainable Forest Management of Native Vegetation Remnants in Brazil 83

Removals in basal area of 70% and 100% presented higher plant density in relation to the control treatment 12 years after intervention, for the other treatments this occurred after 18 years. The response in tree numbers suggests the mentioned cutting cycles ages. In contrast, basal area growth assumes a different behavior from the previous variable because it depends on the development capacity of each species. Thus, up to 1998 there was an accentuated basal area increase of all removal intensities, with variation ranging from 43.05% (80%) up to 90.62% (100%), surpassing the values presented before intervention. The control treatment presented the largest increase, followed by the clear cutting. However 18 years after installation of the experiment (in 2004), clear cutting (14.75 m2/ha) surpassed the control treatment (12.91 m2/ha). This demonstrates the great recovery capacity of the Cerrado after its structure has suffered intervention. Volume behaved in a manner similar to basal area. As far as a constant wood volume production is concerned, the results show that for 100% removal of basal area a silvicultural cutting cycle of 12-16 years allows the Cerrado to return to pre-intervention basal area and volume values in the studied area. In the Cerrado, stump and root sprouts are responsible for the larger part of the natural regeneration, when compared to seed rain dispersal (Durigan, 2005). This way, after exploration it is expected that the plants sprout

followed by diameter growth, and then migrate to higher diameter classes.

**Variable Year Treatments (basal area removal %)** 

Table 2. Number of trees, basal area and volume per hectare in the different measurement dates (1986, 1996, 1998 e 2004). Equal letters in the same column (capital) or line (lower case) indicate that the values are equal, according to the Scott-Knott means grouping test at a 95%

confidence level.

 1986 1716 1716 1716 1716 1716 1716 1996 1933 b B 1520 a A 1769 a A 1707 a A 1655 a A 2155 c A % 12.65 -11.43 3.09 -0.53 -3.58 25.56 Number of trees/ha 1998 1993 a B 1803 a B 2007 a B 1976 a B 1915 a B 2477 b B % 16.14 5.07 16.98 15.15 11.61 44.35 2004 1820 a A 1832 a B 2044 b B 2011 b B 1853 a A 2550 c B % 6.06 6.76 19.11 17.17 7.97 48.62 1986 6.72 6.72 6.72 6.72 6.72 6.72 1996 12.94 c A 9.85 b A 9.66 b A 8.07 a A 8.15 a A 10.72 b A % 92.56 46.63 43.8 20.1 21.33 59.49 Basal area (m2/ha) 1998 13.43 b A 11.01 a A 10.32 a A 9.61 a B 9.71 a B 12.81 b B % 99.85 63.9 53.6 43.05 44.48 90.62 2004 12.91 b A 12.03 b B 11.26 a B 10.7 a C 10.94 a C 14.75 c C % 92.09 78.97 67.56 59.22 62.85 119.51 1986 21.61 21.61 21.61 21.61 21.61 21.61 1996 44.64 c A 33.52 b A 32.81 b A 26.79 a A 27.1 a A 36.71 b A % 106.05 55.1 51.81 23.95 25.41 69.86 Volume (m³/ha) 1998 46.32 c A 37.79 b B 35.25 a A 32.62 a B 32.98 a B 44.18 b B % 114.34 74.87 63.13 50.94 52.6 104.44 2004 44.53 b A 41.43 a B 38.68 a B 36.64 a B 37.54 a C 50.75 b C % 106.03 91.71 79 69.56 73.68 134.82

**0 50 70 80 90 100** 

The era of large *Pinus* spp. and *Eucalyptus* spp. reforestation allowed for the gradual substitution of native wood use, contributing to the protection and preservation of remaining natural areas. Even with the decreased wood use from native forests, the Cerrado vegetation is still being exploited, due to low costs of wood produced. According the Brazilian Forest Service - SFB (2010) the total wood volume in the Cerrado is 870 million m3, with an aboveground biomass of 496 million tonnes. Starting from this available stock it is necessary to draw plans and rules for its exploration, define the optimum cutting cycle without causing negative impacts to local biodiversity, and at the same time promote the increase of biomass.

In the past, and still nowadays in some regions, there were not any technical or scientific procedures to apply the efficient management of this vegetation, where the land owner established the traditional process that combined fire and deforestation for conversion into agricultural areas across the landscape (land use change).

The knowledge of the optimum cutting cycle is a predominant factor for the administration of these forests. Through its determination a detailed and exact management plan can be prepared, informing the ideal level of wood removal to ensure sustainability over time. Allied to this information, the knowledge of floristic composition correlated with environmental and spatial factors enables a holistic understanding of the system, contributing to the development of new silvicultural techniques and exploration criteria.

Forest management seems to be a good alternative in combating rampant deforestation, contributing to the reduction of native vegetation conversion in to grasslands, agriculture and degraded areas. The activities to be considered in a sustainable management should include: available forest resource inventory with a characterization of its structure and forest site; identification, analysis and minimization of environmental impacts; study of technical, economical and social viability of the project; adoption of forestry exploration procedures that minimize ecosystem damage; checking if the remaining stock is sufficient to ensure sustained production; and the adoption of an appropriate post exploration silvicultural system.

The sustainable forest management of the Cerrado case study is part of a set of experiments and research developed by the Federal University of Lavras and its Forest Science Department, dating back from the 80's until the present. The studies were conducted in the Minas Gerais State with reference to the works of Lima (1997), Mello (1999), Mendonça (2000), Oliveira (2002), Oliveira (2006a), Oliveira (2006b), and Scolforo et al. (2008a).

The main issue in vegetation management is the degree of exploration or cutting intensity to be applied, because the lack of this information leads to losses to the environment. Thus, a study was conducted in a Cerrado *Sensu Stricto* in the State of Minas Gerais (municipality of Coração de Jesus). Six intensities of basal area removal (0%, 50%, 70%, 80%, 90% and 100%) were tested and subsequent evaluation in 1986 (year of implementation of the experiment), 1996, 1998 and 2004. The experiment was installed in an area of 30 ha being applied 6 treatments/removal criteria and 5 repetitions per treatment, with sample plots of 600m2. The individuals were identified botanically, and the criteria for measurement was a circumference at breast height (CBH) 15.7 cm. The purpose of the study was to verify the influence of the cutting intensity in recovery time of number of individuals, volume and basal area, as well as the behavior of the tree species diversity. Due to initial variation between treatments (1986), a correction factor was applied permitting comparison of the results in different periods. The results can be seen in Table 2. A gradual increase in the number of individuals occurred in all treatments after exploration. This fact was expected since Cerrado plants feature a great sprouting capacity, as noted in the works of Ferri (1960), Rizzini (1971), Thibau (1982), Toledo Filho (1988), among others.

The era of large *Pinus* spp. and *Eucalyptus* spp. reforestation allowed for the gradual substitution of native wood use, contributing to the protection and preservation of remaining natural areas. Even with the decreased wood use from native forests, the Cerrado vegetation is still being exploited, due to low costs of wood produced. According the Brazilian Forest Service - SFB (2010) the total wood volume in the Cerrado is 870 million m3, with an aboveground biomass of 496 million tonnes. Starting from this available stock it is necessary to draw plans and rules for its exploration, define the optimum cutting cycle without causing negative

In the past, and still nowadays in some regions, there were not any technical or scientific procedures to apply the efficient management of this vegetation, where the land owner established the traditional process that combined fire and deforestation for conversion into

The knowledge of the optimum cutting cycle is a predominant factor for the administration of these forests. Through its determination a detailed and exact management plan can be prepared, informing the ideal level of wood removal to ensure sustainability over time. Allied to this information, the knowledge of floristic composition correlated with environmental and spatial factors enables a holistic understanding of the system, contributing to the development of new silvicultural techniques and exploration criteria. Forest management seems to be a good alternative in combating rampant deforestation, contributing to the reduction of native vegetation conversion in to grasslands, agriculture and degraded areas. The activities to be considered in a sustainable management should include: available forest resource inventory with a characterization of its structure and forest site; identification, analysis and minimization of environmental impacts; study of technical, economical and social viability of the project; adoption of forestry exploration procedures that minimize ecosystem damage; checking if the remaining stock is sufficient to ensure sustained

impacts to local biodiversity, and at the same time promote the increase of biomass.

production; and the adoption of an appropriate post exploration silvicultural system.

(2000), Oliveira (2002), Oliveira (2006a), Oliveira (2006b), and Scolforo et al. (2008a).

Rizzini (1971), Thibau (1982), Toledo Filho (1988), among others.

The sustainable forest management of the Cerrado case study is part of a set of experiments and research developed by the Federal University of Lavras and its Forest Science Department, dating back from the 80's until the present. The studies were conducted in the Minas Gerais State with reference to the works of Lima (1997), Mello (1999), Mendonça

The main issue in vegetation management is the degree of exploration or cutting intensity to be applied, because the lack of this information leads to losses to the environment. Thus, a study was conducted in a Cerrado *Sensu Stricto* in the State of Minas Gerais (municipality of Coração de Jesus). Six intensities of basal area removal (0%, 50%, 70%, 80%, 90% and 100%) were tested and subsequent evaluation in 1986 (year of implementation of the experiment), 1996, 1998 and 2004. The experiment was installed in an area of 30 ha being applied 6 treatments/removal criteria and 5 repetitions per treatment, with sample plots of 600m2. The individuals were identified botanically, and the criteria for measurement was a circumference at breast height (CBH) 15.7 cm. The purpose of the study was to verify the influence of the cutting intensity in recovery time of number of individuals, volume and basal area, as well as the behavior of the tree species diversity. Due to initial variation between treatments (1986), a correction factor was applied permitting comparison of the results in different periods. The results can be seen in Table 2. A gradual increase in the number of individuals occurred in all treatments after exploration. This fact was expected since Cerrado plants feature a great sprouting capacity, as noted in the works of Ferri (1960),

agricultural areas across the landscape (land use change).

Removals in basal area of 70% and 100% presented higher plant density in relation to the control treatment 12 years after intervention, for the other treatments this occurred after 18 years. The response in tree numbers suggests the mentioned cutting cycles ages. In contrast, basal area growth assumes a different behavior from the previous variable because it depends on the development capacity of each species. Thus, up to 1998 there was an accentuated basal area increase of all removal intensities, with variation ranging from 43.05% (80%) up to 90.62% (100%), surpassing the values presented before intervention. The control treatment presented the largest increase, followed by the clear cutting. However 18 years after installation of the experiment (in 2004), clear cutting (14.75 m2/ha) surpassed the control treatment (12.91 m2/ha). This demonstrates the great recovery capacity of the Cerrado after its structure has suffered intervention. Volume behaved in a manner similar to basal area. As far as a constant wood volume production is concerned, the results show that for 100% removal of basal area a silvicultural cutting cycle of 12-16 years allows the Cerrado to return to pre-intervention basal area and volume values in the studied area. In the Cerrado, stump and root sprouts are responsible for the larger part of the natural regeneration, when compared to seed rain dispersal (Durigan, 2005). This way, after exploration it is expected that the plants sprout followed by diameter growth, and then migrate to higher diameter classes.


Table 2. Number of trees, basal area and volume per hectare in the different measurement dates (1986, 1996, 1998 e 2004). Equal letters in the same column (capital) or line (lower case) indicate that the values are equal, according to the Scott-Knott means grouping test at a 95% confidence level.

Sustainable Forest Management of Native Vegetation Remnants in Brazil 85

by Souza et al. (2011) who related the impact of forest management in a Cerrado. The authors demonstrated that the oristic diversity increased over the years in all areas subject to vegetation removal, and did not differ statistically. They also concluded that eleven years after intervention, tree diversity change occurred in all treatments, inclusively in the

Information Remaining (%) 100 75 50 25 0

Fig. 3. Floristic dendrogram considering all treatments of percentage basal area removal and measurement dates, where: A - 0% (1996); B - 50% (1996); C - 70% (1996); D - 80% (1996); E - 90% (1996); F - 100% (1996); G - 0% (1998); H - 50% (1998); I - 70% (1998); J - 80% (1998); K - 90% (1998); L - 100% (1998); M - 0% (2004); N - 50% (2004); O - 70% (2004); P - 80% (2004);

The detreded correspondence analysis (DCA) was applied to support the discussions and interpretation of floristic recovery after intervention in 1986. The DCA was developed by Hill & Gauch (1980) being a multivariate method that contributes to analyze the connection among environment, species and other variables. Following the graphic result (Figure 4) the treatments 0% and 100% basal area removal are still close (dotted line circle), which suggest no significant loss of tree species after 1986. The rapid regeneration (sprouting) after cutting

Considering only the tree stratum, it was noted in all treatments that 12 years after intervention the remaining vegetation presented diversity indexes similar to those found in Cerrado vegetation in other regions of Brazil not subject to intervention. According to Scolforo et al. (2008a) Minas Gerais state possesses potential for the sustainable timber

Currently, the recommended option for sustainable management of the Cerrado is the clear cutting in strips, which consists in removing 100% of individuals (excepting tree species prohibited by legislation), realized in a maximum of 50% of the area destined for exploration (Figure 6). The explored and unexplored strips must be alternated, where the unexplored strips must have greater or equal dimensions in relation to the explored strips. The objective is to allocate a greater protection of the environment by preventing its degradation, as well

was observed and desirable for establishing the recovery of the physiognomy.

management of the Cerrado, mainly in the North/North-West as shown in Figure 5.

unmanaged control treatment.

Q - 90% (2004) and R - 100% (2004).

A G M N B H D J P F L R E K Q C I O

An economical analysis was carried out to verify the viability of the removal intensities in relation to cutting cycles studied. The method used was the Net Present Value (NPV) considering an infinite planning horizon. Thus, a greater NPV indicates a more lucrative project. Wood production costs were based on the year 2005 (USD 1.00 = R\$2.165), being calculated by hectare of forest, and included depreciation costs (structures, machines, equipments and tools), administration, taxes, social charges, labor costs, alimentation, personal transport, among others. An annual discount rate of 6% was used. The future cycles' productivity was estimated through a Markov chain type prognosis system (OLIVEIRA, 2006a). Table 3 presents NPV results considering cutting cycles of 10, 12 and 18 years.


Table 3. Net present value (US\$/ha) per treatment for cutting cycles of 10, 12 and 18 years.

The smallest economic viability was obtained by removing 50% basal area and the largest in 100% removal, where longer cutting cycles (12, 16 and 18 years) made the lower intensities of basal area removal become unviable. Despite the inviability of certain treatments, charcoal prices suffer great fluctuation in short periods of time, which may make them economically viable. This variation must be closely analyzed, since a price increase in the end product can elevate the number of projects that are economically viable.

A high floristic diversity exists in the study area, with Shannon index values ranging from 3.13 to 3.23. The diversity between treatments was very similar, and the small differences found are perfectly normal in a biological system. These high values indicate that the sprouting levels are sustainable for the maintenance of local tree species diversity of the trees stratum. In summary, the family Fabaceae presented the largest number of species in the six treatments. The family Vochysiaceae presented the largest number of individuals in all treatments. The species *Qualea grandiflora*, *Qualea parviflora*, *Eugenia dysinterica*, *Qualea multiflora*, *Eriotheca pubescens*, *Magonia pubescens*, *Platymenia reticulata*, *Hymenaea stigonocarpa*, *Dimorphandra mollis*, *Caryocar brasiliense*, *Annona crassifolia*, *Buchevania tomentosa*, *Tabebuia ochracea*, *Aspidosperma macrocarpum*, *Sclerolobium aureum*, *Astronium fraxinifolium*, *Bowdichia virgilioides*, *Annona crassifolia*, *Acosmium subelegans*, *Hyptidendron cana* and *Maclinea clausseniana* are those which easily regenerate naturally, possess high basal area and are present in the lower, middle and upper stratum of the Cerrado. These characteristics indicate that these species present potential to be managed.

Figure 3 shows the cluster analysis considering a floristic matrix that included all basal area removal treatments. According to the dendrogram there is a high connection between most of treatments by 25% cut level, which basically formed 3 floristic groups. The major cluster grouped 0% and 100% basal area removal for all survey periods (1996, 1998 and 2004), which suggest a lower risk of tree species loss up to 2004. Similar tendencies were obtained

An economical analysis was carried out to verify the viability of the removal intensities in relation to cutting cycles studied. The method used was the Net Present Value (NPV) considering an infinite planning horizon. Thus, a greater NPV indicates a more lucrative project. Wood production costs were based on the year 2005 (USD 1.00 = R\$2.165), being calculated by hectare of forest, and included depreciation costs (structures, machines, equipments and tools), administration, taxes, social charges, labor costs, alimentation, personal transport, among others. An annual discount rate of 6% was used. The future cycles' productivity was estimated through a Markov chain type prognosis system (OLIVEIRA, 2006a). Table 3 presents NPV results considering cutting cycles of 10, 12

**Basal area reduction Cutting cycle** 

Table 3. Net present value (US\$/ha) per treatment for cutting cycles of 10, 12 and 18 years. The smallest economic viability was obtained by removing 50% basal area and the largest in 100% removal, where longer cutting cycles (12, 16 and 18 years) made the lower intensities of basal area removal become unviable. Despite the inviability of certain treatments, charcoal prices suffer great fluctuation in short periods of time, which may make them economically viable. This variation must be closely analyzed, since a price increase in the

A high floristic diversity exists in the study area, with Shannon index values ranging from 3.13 to 3.23. The diversity between treatments was very similar, and the small differences found are perfectly normal in a biological system. These high values indicate that the sprouting levels are sustainable for the maintenance of local tree species diversity of the trees stratum. In summary, the family Fabaceae presented the largest number of species in the six treatments. The family Vochysiaceae presented the largest number of individuals in all treatments. The species *Qualea grandiflora*, *Qualea parviflora*, *Eugenia dysinterica*, *Qualea multiflora*, *Eriotheca pubescens*, *Magonia pubescens*, *Platymenia reticulata*, *Hymenaea stigonocarpa*, *Dimorphandra mollis*, *Caryocar brasiliense*, *Annona crassifolia*, *Buchevania tomentosa*, *Tabebuia ochracea*, *Aspidosperma macrocarpum*, *Sclerolobium aureum*, *Astronium fraxinifolium*, *Bowdichia virgilioides*, *Annona crassifolia*, *Acosmium subelegans*, *Hyptidendron cana* and *Maclinea clausseniana* are those which easily regenerate naturally, possess high basal area and are present in the lower, middle and upper stratum of the Cerrado. These characteristics indicate that these species present potential

Figure 3 shows the cluster analysis considering a floristic matrix that included all basal area removal treatments. According to the dendrogram there is a high connection between most of treatments by 25% cut level, which basically formed 3 floristic groups. The major cluster grouped 0% and 100% basal area removal for all survey periods (1996, 1998 and 2004), which suggest a lower risk of tree species loss up to 2004. Similar tendencies were obtained

end product can elevate the number of projects that are economically viable.

50% -19.62 -26.72 -55.45 70% 20.04 2.15 -38.12 80% 10.23 9.22 -32.02 90% 29.16 27.12 -19.85 100% 107.88 99.53 26.39

**10 12 18** 

and 18 years.

to be managed.

by Souza et al. (2011) who related the impact of forest management in a Cerrado. The authors demonstrated that the oristic diversity increased over the years in all areas subject to vegetation removal, and did not differ statistically. They also concluded that eleven years after intervention, tree diversity change occurred in all treatments, inclusively in the unmanaged control treatment.

Fig. 3. Floristic dendrogram considering all treatments of percentage basal area removal and measurement dates, where: A - 0% (1996); B - 50% (1996); C - 70% (1996); D - 80% (1996); E - 90% (1996); F - 100% (1996); G - 0% (1998); H - 50% (1998); I - 70% (1998); J - 80% (1998); K - 90% (1998); L - 100% (1998); M - 0% (2004); N - 50% (2004); O - 70% (2004); P - 80% (2004); Q - 90% (2004) and R - 100% (2004).

The detreded correspondence analysis (DCA) was applied to support the discussions and interpretation of floristic recovery after intervention in 1986. The DCA was developed by Hill & Gauch (1980) being a multivariate method that contributes to analyze the connection among environment, species and other variables. Following the graphic result (Figure 4) the treatments 0% and 100% basal area removal are still close (dotted line circle), which suggest no significant loss of tree species after 1986. The rapid regeneration (sprouting) after cutting was observed and desirable for establishing the recovery of the physiognomy.

Considering only the tree stratum, it was noted in all treatments that 12 years after intervention the remaining vegetation presented diversity indexes similar to those found in Cerrado vegetation in other regions of Brazil not subject to intervention. According to Scolforo et al. (2008a) Minas Gerais state possesses potential for the sustainable timber management of the Cerrado, mainly in the North/North-West as shown in Figure 5.

Currently, the recommended option for sustainable management of the Cerrado is the clear cutting in strips, which consists in removing 100% of individuals (excepting tree species prohibited by legislation), realized in a maximum of 50% of the area destined for exploration (Figure 6). The explored and unexplored strips must be alternated, where the unexplored strips must have greater or equal dimensions in relation to the explored strips. The objective is to allocate a greater protection of the environment by preventing its degradation, as well

Sustainable Forest Management of Native Vegetation Remnants in Brazil 87

Fig. 6. Clear cutting in alternate strips scheme applied in the Brazilian Cerrado (Scolforo et

Havested area

The joint analysis of these studies show that the exploration of the Cerrado can be economically viable, being mainly dependent on the level of intervention, cutting cycle, productivity, land costs and market variables. The studies related here were focused in the tree stratum of the forests and as such consist of preliminary studies of the sustainability of cerrado management. Further studies on how forest management affects the fauna and other aspects of the flora (e.g. trees with DBH smaller than 5cm and herbaceous stratum) are required to provide more information on the impacts of forest management on the Cerrado. Multiple use of the Cerrado is an option, such as the already marketed species of *Dimorphandra mollis* (favela), used in the pharmaceutical industry, and the food products

Formation processes of an environment over thousands of years gradually promote species selection, encouraging the development of strategic mechanisms to overcome the difficulties imposed by each habitat. The spatial distribution of species in a landscape presents a selective character, which added to between species competition, directs the occurrence and dynamics of a forest. As such, candeia (*Eremanthus* spp) predominantly occupies high altitude field areas, being quite recurrent in the State of Minas Gerais (Brazil), as shown in

Candeia is of the Asteraceae family, an ecotone species typical of transitional areas between wooded and grasslands. Even thought it presents several characteristics of pioneer species such as: production of large quantities of seeds, seeds dispersed by wind, high-density natural regeneration in open gaps, it must not be framed as such since its lifespan can exceed 50 years. There are several species of candeia, however *Eremanthus erythropappus*

100 m 100 m 100 m

Harvest on strips

Natural regeneration area

Stands

Harvest on strips

Protected area

derived from pequi (*Caryocar brasiliensis*) and baru (*Dipteryx alata*).

al., 2008a).

**2.2 Candeia tree** 

Figure 7.

as the possibility of seed dispersal in the explored area, therefore helping to promote natural regeneration, which as stated earlier is achieved primarily by sprouting.

Fig. 4. The DCA analysis considering all treatments of percentage basal area removal and measurement dates, where: A - 0% (1996); B - 50% (1996); C - 70% (1996); D - 80% (1996); E - 90% (1996); F - 100% (1996); G - 0% (1998); H - 50% (1998); I - 70% (1998); J - 80% (1998); K - 90% (1998); L - 100% (1998); M - 0% (2004); N - 50% (2004); O - 70% (2004); P - 80% (2004); Q - 90% (2004) and R - 100% (2004). The blue squares represent the treatments and the open blue circles are the species.

Fig. 5. Minas Gerais State's regions with potential for the application of sustainable forest management of the Cerrado.

Fig. 6. Clear cutting in alternate strips scheme applied in the Brazilian Cerrado (Scolforo et al., 2008a).

The joint analysis of these studies show that the exploration of the Cerrado can be economically viable, being mainly dependent on the level of intervention, cutting cycle, productivity, land costs and market variables. The studies related here were focused in the tree stratum of the forests and as such consist of preliminary studies of the sustainability of cerrado management. Further studies on how forest management affects the fauna and other aspects of the flora (e.g. trees with DBH smaller than 5cm and herbaceous stratum) are required to provide more information on the impacts of forest management on the Cerrado. Multiple use of the Cerrado is an option, such as the already marketed species of *Dimorphandra mollis* (favela), used in the pharmaceutical industry, and the food products derived from pequi (*Caryocar brasiliensis*) and baru (*Dipteryx alata*).
