5.2 Brazil's Araucaria Rainforest

ETFRN NEws 50: NovEmbER 2009 5.2 Brazil’s Araucaria rainforest: climate change and reforestation WOLF ENGELS ancient conifer rainforest in Brazil Trees of the genus Araucaria are ancient conifers and have been called “living fossils” (hampp, breuninger and mertz 2000). During the permian period these trees were wide- spread, but after fragmentation of the Gondwana continent their descendants survived only in the extreme western and eastern margin of their original distribution. most of the 20 remaining Araucaria species occur in far eastern regions; only two taxa are left in south america (Golte 1993; mecke, mille and Engels 2005): • Araucaria araucana is distributed in the Chilean proTeCTing The andes; and remnanTs and parTial • Araucaria angustifolia is found in the south of brazil and adjacent areas of argentina and resToraTion of paraguay (rambo 1960). ArAucAriA foresTs Can help To deCrease The effeCTs of only the latter species has formed large forests; these once covered the coastal mountains of the ClimaTe Change in souThern brazil. mata atlântica at latitudes between 18° and 30°s (Figure 1). The Araucaria rainforests once extended over 250,000 km² in the range of the south brazilian states of rio Grande do sul, santa Catarina and paraná (sos mata atlân- tica 1998), mainly on sites at altitudes of 300 to 1,800 metre above sea level and reaching a width of up to 800 km. in sao paulo forests covered about 80 percent of the land; in rio Grande do sul they covered 50 percent. Threats to Araucaria angustifolia adult Araucaria trees dominate the canopy of this ecosystem (see photo above), unique in tropical and subtropical ranges. after 1950 the Araucaria forests were subject to massive clearings, due to timber logging, agriculture and settlements. Farmland formerly dominated the countryside of Araucaria woodlands. on this land traditional small-scale agriculture was combined with timber harvesting. This allowed generations of descendants of immigrants, who arrived during the 19th century from Germany and other European countries, to live from the sustainable use of their land. once the trees were cut down, the local wood-processing industry collapsed. wolf engels works for brasilien-Zentrum, university of Tübingen, Germany and puCrs, porto alegre, r s, brazil. 114 5.2 bRazil’s ArAucAriA RaiNFoREsT: ClimaTE ChaNgE aNd REFoREsTaTioN Figure 1. south brazilian Araucaria rainforest (shown in green) about 50 years ago scattered distribution only north of sao paulo Brasilia rio de Janeiro são paulo porto alegre The local climate also began to change and the farmers’ standard of living decreased rapidly; many left their homes. some people managed to find new farmland in the north, for instance in mato Grosso or even far away in amazonia. The reform of landed property, often discussed, is still unresolved in brazil, leading to the sem terra (“landless”) move- ment and occupations of unused fazendas (farms), and creating severe conflicts. most of the rural population migrated to the fast-growing cities, increasing the urban problems of joblessness and lack of housing. The socio-economic turbulence resulting from massive forest clearings remained widely unresolved until now. only fragments of the originally continuous woodlands are left. in the state of paraná, for example, no more than one percent is left of the Araucaria forests, which formerly covered more than seven million ha; the tree was often called the paraná pine (mertz et al. 2003). meanwhile, the mata atlântica has become a biosphere reserve and was declared a highly endangered hotspot region that requires immediate protection measures (UNEsCo natural science 2007). as recently demonstrated, climate change causes considerable pressure for the remnants of Araucaria rainforests. Conservation of the tree species Araucaria angustifolia is neces- sary; an increase of ambient temperatures and changes in the atmospheric circulation were modeled to predict the expected climatic impact (silveira wrege et al. 2007). The alarming consequences of continued climate changes to the environmental conditions in southern brazil and in particular to the survival of the important Araucaria rainforest ecosystem are well documented. Araucaria rainforests and climate change The large area of Araucaria rainforest within the biome of the mata atlântica developed during the past 5,000 years as part of the dynamic vegetation changes caused by the increasingly humid climate of the southeastern neotropics (behling 2005). open land with at least seasonal bare ground has replaced the rainforests and alarming climate changes have been observed. The forest’s function as a water reservoir has been lost, and the diminished biodiversity has reduced the stability of woodland ecosystems. records of surface temperatures reveal an extreme warming in the range of 2.0–3.5°C, particularly in localities without permanent vegetation cover (hamza, Cavalcanti and benyosef 2007), with a subsequent rise of hot air into the upper atmosphere. This leads to storms sucking 115 ETFRN NEws 50: NovEmbER 2009 in cold antarctic airstreams, which now extend far north, and to resulting frost periods in the tropical state of minas Gerais, which can kill coffee crops (blomberg 2000). in northeast brazil, the atlantic rainforest has been cleared since the introduction of sugarcane cultivation in the 17th century (Coimbra-Filho and de Gusmao Camara 1996). because large areas there have thin cerrado and caatinga vegetation, the impacts of climate change are less evident, manifested mostly in more frequent heavy rainfall in usually dry regions (rao et al. 2006). natural reforestation in the pró-Mata project at the time of the first united nations Conference on Environment and Development (unCED), in June 1992, the pontifical Catholic university of rio Grande do sul (puCrs) in porto alegre, together with Germany’s university of Tübingen, established an Araucaria forest protectorate on the previously woody serra Geral of rio Grande do sul. The 5,000-ha area was named pró-mata (Engels 2003). The area was destined for research and conservation and would attain the status of a nature reserve, owned and administered by puCrs. support came from the local municipality of sao Francisco de paula, from companies (especially a. stihl), the GEo foundation in hamburg and the university of Tübingen. as well as intensive studies on fauna and flora, experiments on natural reforestation were initiated in coop- eration with the university of applied Forest science at rottenburg (Engels and heinle 2003). about 30,000 seedlings of Araucaria angustifolia and Ilex paraguayensis (Yerba maté) were planted by graduate students from rottenburg. The concept, then new, was to plant young trees right into existing secondary vegetation (see photo, left), which consisted mainly of baccharis bushes and mimosa trees. During the last 12 years the young Araucaria trees reached heights of five metres and more. The project was part of the shiFT program financed by the German ministry of Education and research. The final report was published in 2002 (heinle 2002). The intent of the program was to accelerate the regeneration process of natural Araucaria rainforest considerably and, at the same time, to avoid the costs and negative effects of removing the existing vegetation. as far as is known, this attempt at reforestation in secondary vegetation of pioneer plants had previously not been tried in brazil. The key factor was to not clear the land by cutting and burning the shrubs, but to make use of the existing biomass. This provides a humid environment that allows the young Araucaria trees to grow. in addition, because of the abundance of green leaves in the diverse shrub vegetation, the Araucaria needles are not the only available forage for leafcutter ants, which usually attack monoculture plantations of Araucaria (Zanuncio 1993). most importantly, the seedlings are not trying to grow on bare soil, with all its negative effects. 116 5.2 bRazil’s ArAucAriA RaiNFoREsT: ClimaTE ChaNgE aNd REFoREsTaTioN Forest politics in Brazil since 2006 the brazilian government has improved its legislation on nature conservation and initiated reforestation programs. sustainable use of forests and protection of native vegetation are now regulated by public laws 11.284 and 11.428. The national biodiversity program (pronabio) was initiated by decree in 1994, but financial support for its initia- tives was provided only recently. a worldwide increase in understanding the importance of forests to the global climate had already brought about some change in public opinion on the relevance of reforestation in brazil. it is hoped that the measures now planned by politicians will be successful in reducing the negative and already alarming effects of climate change, particularly the damage to the formerly vast rainforests. warnings about the negative consequences of the loss of brazilian woodlands was expressed again and again, particularly by nGos such as sos mata atlântica (1998). only recently have the federal and state institutions responsible for environmental issues held discussions with these private organizations. support is required not only from national sources, but from international agencies like the world bank; this could effectively initiate reforestation activities. This will only take place if the problem is tackled at the local and regional level, which is, in fact, intended by the new federal legislation. winning the support of the public will be a challenge for politicians

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