4. MATERIAL Y MÉTODO
4.12. Hábitos de consumo
Adelar Mantovani and Nivaldo Peroni
Domestication of landscapes
Multiple uses of distinct environments have historically favoured many past and present human populations in the discovery of plant resources. Various studies have been carried out on the impact of human activities on changes in species composi-tion or their demography in landscapes. Historical ecology seeks to understand these relationships by looking at such transformations of landscapes as mediated by human actions (Balée, 2006).
The historical ecology perspective complements that of focusing on the domestication of landscapes, as described by Peroni et al. (Chapter 3.4), as it enhances our understand-ing of how human activities have transformed landscapes and to what extent these land-scapes have increased the productivity of specific biological resources. The domestication of landscapes results from human management of biotic and even abiotic components of the environment. Such a process can take many generations, but may contribute to an increase in the availability of useful species, change the demographic structure of indi-vidual species and maximize the productivity of the environment (Clement, 1999).
Landscape conservation: a unique strategy for sustaining domestication
In Brazil, many biological scientists focus their research on the threatened Atlantic Forest. However, studies rarely focus on its historical ecology and just a few spe-cies and associated landscapes have been studied from the domestication perspective (Reis et al., 2010). Little focus is given to species that continue to be domesticated by humans today. For such species, traditional people employ management prac-tices that may also be of relevance to the conservation of those landscapes. We focus here on the interaction between people and their landscape and, in particular, on their management of cultural keystone species, thereby looking for transformation at species and landscape levels. Such an approach appears to be the most logical as it targets the dynamic relationship between people, biodiversity and landscapes.
Caívas: managed patches of the Araucaria Atlantic Forest
The mixed ombrophilous forest (MOF), also called the Araucaria Atlantic Forest, is one of the most endangered ecosystems of the Atlantic Forest. Yerba mate (Ilex
152 Maurício Sedrez dos Reis et al.
paraguariensis) and araucaria (Araucaria angustifolia) are typical of this forest type. It is estimated that MOF remnants occupy just 1–4% of their original area, and are cur-rently spread over small, dispersed fragments (Guerra et al., 2002).
In the northern plateau of Santa Catarina (see Figure 3.5.1), small-scale farmers manage existing MOF fragments, which form part of an area that is used for cat-tle rearing, extraction of firewood, commercial extraction of yerba mate and pinhão (araucaria seed). The extraction activities complement other commercial farm activi-ties that include maize and soybean cultivation, and cattle husbandry for dairy pro-duction. Local farmers refer to these managed forest fragments as caívas, landscape units or patches within the matrix of a fragmented forest. In the composition and structure of their plant communities, these caívas reflect past and present human influences. Araucaria and yerba mate predominate in the caívas, together with sev-eral species of the Myrtaceae family, such as the araçás (Psidium spp.) and the guavi-rovas (Compomanesia spp.).
From an ecological perspective, caívas are heterogeneous landscape units, and they range in composition from areas with dense herbaceous vegetation, dominated by yerba mate, to forested areas in the advanced stages of secondary succession. The management of these areas is quite variable but may include the following three basic elements, in varying degrees of intensity: the extraction of yerba mate, cattle rearing and seasonal management.
Yerba mate
Yerba mate is an arboreal species of the Aquifoliaceae family, which has stimulat-ing properties and is consumed as chimarrão, a typical tea drink common in southern Brazil, the northern provinces of Argentina (Corrientes and Missiones), Paraguay and Uruguay. The yerba plant is an evergreen shrub or small tree, which grows to
Santa Catarina Northern Plateau
of Santa Catarina
Rio Grande do Sul
Florianópolis Paraná
Atlantic Ocean Argentina
Brazil
Figure 3.5.1 Map showing the location of the Northern Plateau of Santa Catarina.
Caívas and the conservation of Atlantic forest landscapes in Brazil 153 about 15 m tall. Its leaves are often called yerba in Spanish or erva in Portuguese, both of which mean ‘herb’. The leaves contain caffeine and related compounds, are har-vested commercially and are consumed as a hot or cold tea. Variations in consump-tion and processing techniques have evolved over time from those initially practised by the various groups of indigenous peoples (in particular the Guarani) that previously inhabited this part of the continent. Today, the use of yerba mate partly characterizes the way of life of many rural and urban human populations who live throughout the southern inland plains of Brazil and its neighbouring countries, where the daily con-sumption of chimarrão or mate is common. Drinking chimarrão or mate provides an impetus for gathering with relatives and friends in southern Brazil, northern Argen-tina, Paraguay and Uruguay. Sharing is ritualistic and has its own set of rules, which vary from community to community within the region.
The economic exploitation of yerba mate was already significant in the eighteenth century, even before the start of commercial timber exploitation. Currently, yerba mate can be cultivated as a homogeneous crop, using selected varieties, but the leaves may also be extracted from the caívas, where extractors gather the leaves of ‘native’
yerba mate directly from forest populations.
In areas where yerba mate is harvested from managed forests, the harvesting of leaves, called poda (‘pruning’), is carried out at intervals of 2–4 years, depending on the management strategy adopted by the producer. In addition, many producers tend to practise the management technique of roçar (‘cleaning’) in areas of yerba mate to promote leaf growth, or to facilitate the management of the productive area. In general, farmers do not cultivate crops within the yerba mate areas. Within the forest, the management of each yerba mate area is usually carried out by the same individu-als for many years. Some producers claim that their yerba mate plants, the leaves of which are continuously harvested, are more than 100 years old.
Despite the higher productivity of homogeneous plantations, producers focus on native yerba mate plants. This preference arises from the higher prices that producers get in the market for the mate extracted from native plants. According to the palate of chimarrão consumers in southern Brazil, native yerba mate has a less bitter taste than that cultivated in plantations (Vieira et al., 2003). Thus, producers who still extract yerba mate from the understorey of araucaria forest fragments have a more valuable product than that from homogeneously cultivated plantations. Currently, the price difference can amount to a premium of 70% more for the native yerba mate.
In the northern plateau of Santa Catarina, the average property size is 45 hectares, approximately 23 hectares of which are covered by forest. Almost half of the proper-ties possess forest areas from which producers extract yerba mate. We can divide the landscape into two main types, based on the management practices undertaken in forest fragments. The first type is called traditional simplified management, in which yerba mate is exploited using simple management practices and minimal human intervention. The second type is traditional caíva management, in which yerba mate is exploited with local management practices, cattle rearing in the understorey and intense human interventions.
The degree of intervention in the landscape, depending on which of the two man-agement types is applied, results in a difference in forest structure and species density, with implications on the arboreal forest layer. In areas where traditional simplified
154 Maurício Sedrez dos Reis et al.
management techniques are applied, the average density of individuals of all species is 5976 plants per hectare (plants/ha), with yerba mate presenting a density of 1067 plants/ha. For traditional caíva management, where management practices are more intense, the density of individuals of all species is 805 plants/ha, with yerba mate pre-senting a density of 324 plants/ha.
The high densities of yerba mate in landscapes managed by human populations show that it is a species that has remained within the forest fragments. Hence, once sustained, the management of native yerba mate favours the conservation of forest fragments, thereby contributing to in situ conservation through the management of yerba mate in caívas as a plant genetic resource.
Araucaria
The most common uses of the araucaria are primarily associated with timber pro-curement (Guerra et al., 2002). Timber exploitation increased from the early twen-tieth century until the 1970s. It was followed by the arrival of European immigrants in the south, resulting in extension of the agricultural frontier, as described by Assis et al. (Chapter 3.2). The timber exploitation of araucaria made a significant impact on the Brazilian economy and contributed to the devastation of major areas of the Atlantic Forest, especially in the southern states. As a result of its predatory exploita-tion, associated with the partial destruction of its habitat, araucaria is considered to be an endangered species according to the official list of endangered Brazilian flora species.
The seed of the araucaria, the pinhão, can be eaten and used to form a significant part of the diet for indigenous peoples, such as Xokleng and Caingang (Bitencourt and Krauspenhar, 2006). Nowadays, it is considered to be a delicacy and is greatly appreciated by both rural and urban populations.
Producers have reported significant variations in productivity over the years. An understanding of this variation may be useful for the design of interventions target-ing the conservation and continued use of the species. However, much still remains unclear on the production of pinhão (Reis et al., 2010). Estimations of productivity vary from 45 kg/ha of seed (Vieira da Silva and Reis, 2009) to more than 4000 kg/ha (Solórzano-Filho, 2001). This variation may be related to differences in estimation methods, age of the individuals, soil fertility and annual variations in productivity.
Few studies have investigated the structure of the pinhão supply chain, or tried to improve it. Studies carried out in the states of Santa Catarina and Paraná indicated that the pinhão value chain involves pinhão producers and collectors, intermediaries, wholesalers and retailers (Santos et al., 2002; Vieira da Silva and Reis, 2009). An inves-tigation into this value chain showed that the price of pinhão fluctuates both during the harvest and between harvests. The variation in price is influenced by the availability of pinhão, the productivity of which is irregular and unpredictable, and by demand for the product, which appears to increase in the event of a severe winter. Understanding how ecological aspects of the species and the variations that exist among araucaria populations or varieties influence the supply chain is important in order to align the conservation of this plant genetic resource with the effective rural development of the farming communities that manage the species in their caíva landscape.
Caívas and the conservation of Atlantic forest landscapes in Brazil 155 Forest landscape conservation and its integration with
araucaria and yerba mate
Araucaria and yerba mate are typical in the everyday lives of households in the north-ern plateau of Santa Catarina area and other regions where the MOF is the primary forest type. For yerba mate, this means particular care is given to the species popu-lations, favouring their growth and productivity. Some households in the northern plateau give names to araucaria individuals that refer to the history, unique structure and seed capacity production of an individual tree. Assis et al. (2010b) conducted an analysis of the MOF as a domesticated landscape and identified araucaria and yerba mate as its cultural keystone species. The results indicated that both species are among the most valued, demonstrating high cultural indicator levels in all aspects of the analysis. Much ethnobotanical information has nevertheless been lost, as many farmers no longer claim to use names for individual araucaria trees as they used to (Vieira da Silva and Reis, 2009).
Symbolic aspects of the two species are important, such as the identification of regional landscapes, as delineated by the presence of araucaria, the consumption of the pinhão, and the preparation and consumption of chimarrão, using yerba mate.
Both species have a unique place in local culture, i.e. there is no other plant species that replaces either of them in the preparation of chimarrão or pinhões, or their com-mercial exploitation for this purpose. This exclusivity, and the continued apprecia-tion by both rural and urban people in southern Brazil, creates a favourable environ-ment to support the manageenviron-ment of the caíva landscape, facilitating the conservation of the Araucaria Atlantic Forest and its two keystone species, but it also contributes to farmers’ livelihoods, which are directly associated with, and vital for, the continuation of this landscape. With the current economic growth in Brazil, it is likely that markets for products with a higher value, such as quality yerba mate and pinhões, will grow.
However, conservation efforts should promote regional products within markets that tend to favour industrialized and global products. In order to encourage farmers to maintain their remaining forest areas, better market conditions for their products may encourage them to alter their management practices in favour of araucaria and yerba mate. These alterations will in the long run provide additional income, and ensure the maintenance of viable populations of both species and a landscape that retains fragments of the once abundant Atlantic Forest.