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Climate change and conservation of angustifolia in Brazil

M. Silveira Wrege, R.C.V. Higa, R. Miranda Britez, M. Cordeiro Garrastazu, V.A. de Sousa, P.H. Caramori, B. Radin and H.J. Braga

Climate vulnerability mapping he ombrophilous (high-rainfall (Hueck, 1953). The Araucaria forest is used to predict areas where tolerant) mixed forest of southern covers 177 600 km2 in Brazil (Leite and climate change will have drastic TBrazil has a canopy dominated Klein, 1990) and 2 100 km2 in effects on given tree species by Parana (Araucaria angustifolia) (Giraudo et al., 2003). or populations, so they can be and is thus also referred to as Araucaria The presence of A. angustifolia in the prioritized for conservation forest (Veloso, Rangel Filho and Lima, Brazilian subtropical area has its origins 1991), even though the composition of in continental drift which resulted in the its vegetation may vary significantly dispersion of Araucaria ancestors along according to latitude, altitude, soil and with other vegetation. Araucaria fossils microclimate (Reitz and Klein, 1966). are distributed throughout the world, This forest type is found only in the but surviving species today are found Neotropics and is typical of the southern only in Australia (seven species) and tableland. South America (two species). The region Araucaria angustifolia forests are of origin of A. angustifolia in southern under considerable pressure today as Brazil is therefore uncertain. During they are usually located in densely popu- the late Pleistocene (the era from 1.8 lated areas. Recent and predicted climate million to 10 000 years ago), elevation change may present a further challenge to of the continental platform to altitudes the future survival of these tree popula- that made the rainy climate suitable for tions. This article describes the origin of A. angustifolia possible at this latitude the Araucaria forest and outlines how it allowed the formation of an ombrophi- has been influenced by climate change lous nucleus or founder population. Sub- throughout the Cenozoic, the most recent sequent geological phenomena caused (and ongoing) geologic era. It points this nucleus to expand and contract over out some of the limitations of current time; at its largest the natural distribution Marcos Silveira Wrege, Rosana Clara attempts to map climate vulnerability reached northeastern Brazil (Veloso, Victoria Higa, Marilice Cordeiro Garrastazu Rangel Filho and Lima, 1991; Leite, and Valderês Aparecida de Sousa are with in the populations described, and con- Embrapa Florestas, the forestry arm of the siders the importance of maintaining 1994). Brazilian Agricultural Research Corporation their genetic variability to enable their Araucaria angustifolia occurs natu- (EMBRAPA), Colombo, Brazil. rally on a variety of soils, from shallow Ricardo Miranda Britez is with the Sociedade adaptation to a changing climate and de Pesquisa em Vida Selvagem e Educação thus their conservation. to deep and from wet to well drained. Ambiental (Society for Wildlife Research and One of the main environmental features Environmental Education, SPVS), , that determines its distribution, and con- Brazil. ABOUT ARAUCARIA FOREST AND Paulo Henrique Caramori is with the Instituto A. ANGUSTIFOLIA sequently its susceptibility to climate Agrônomico do Paraná (Agronomic Institute of In Brazil, Araucaria forest occurs south change, is the presence of frost, which Paraná, IAPAR), Londrina, Brazil. allows the species to outperform com- Bernadete Radin is with the Fundação Estadual of the Tropic of Capricorn between the de Pesquisa Agropecuária (State Foundation for altitudes of 50 and 1 800 m, most fre- peting tree species at the higher altitudes Agrarian Research, FEPAGRO), Porto Alegre, quently between 500 and 1 200 m, and where it thrives. Brazil. The species has been intensively Hugo José Braga is with the Centro de is surrounded by subtropical humid Informações de Recursos Ambientais e de forest. Fragmented populations of A. exploited for timber, and the Araucaria Hidrometeorologia (Centre of Environmental angustifolia also occur in northeast- forest area has also been reduced by Resources Information and Hydrometeorology, expansion of agriculture. Even though EPAGRI/CIRAM), Florianópolis, Brazil. ern Argentina and southeastern Brazil

Unasylva 231/232, Vol. 60, 2009 31 R. HIGA R. HIGA Araucaria angustifolia dominates the forest canopy ago humidity increased, and evidence climate change scenarios on the distribu- at Itaimbezinho Valley, Rio has been found of the presence of A. tion of A. angustifolia. Grande do Sul State, Brazil angustifolia, Drimys brasiliensis and First, an envelope model was used to today A. angustifolia is legally pro- Cyathea sp. Ombrophilous forest did determine the range of favourable climatic tected and its harvesting for timber is not occur on the plateau, but only as conditions for A. angustifolia based on prohibited by law in Brazil, the remain- small populations in refuge areas on a 30-year climatic series from Brazil’s ing areas of the species in its natural the wetter coastal slopes and in river southern region. Climate vulnerability distribution areas are fragmented and valleys (Ledru et al., 1994). Possibly mapping was used to predict the effect scattered, with few large populations between 17 000 and 8 500 years ago, of 1º, 2º and 3ºC increases in temperature remaining. The conservation status the region experienced a series of cli- on the current natural distribution of A. of this forest type is considered criti- mate fluctuations dominated by cold angustifolia. The maps were developed cal. In addition, the age distribution of dry conditions, interrupted by a brief based on linear regression with latitude, the remaining populations is skewed period of higher humidity from 13 000 longitude and elevation to identify zones towards older age classes. to 11 000 years ago. Around 8 500 years potentially suitable for the species under ago, temperatures continued to be low VJGUGUEGPCTKQU6JGOCRURTGFKEVCUKIPKſ- A HISTORY LINKED WITH but humidity began to return, increas- cant reduction of the area suitable for the CLIMATE CHANGE ing the Araucaria presence associated species, indicating that with a temperature Palaeontological studies have attempted with species of the genera Symplocos, increase of 3ºC, only a small area at the to relate past climate to the current Drimys, Lithraea, Podocarpus, Myrsine highest part of the southern Brazilian table- vegetation in the southern tableland of and Alchornea (Ledru, 1993). land would be favourable (Figure 1). Brazil. It is assumed that three to four The current humid conditions returned Second, a regional circulation model periods of severe climate fluctuations from about 4 300 years ago (Behling, developed by the Brazilian National in the Cenozoic have influenced current 2005). As the conditions became more Institute for Space Research (INPE) was vegetation distribution and composition. steadily humid the Araucaria forest used to generate scenarios for 2010, 2030 Two dry periods have occurred, a dras- expanded to previous subtropical grass- and 2050, based on changes in atmos- tic drought episode in the Pleistocene lands at higher altitudes. Ombrophilous pheric circulation predicted by IPCC and a milder one during the subsequent HQTGUVJCUGZRCPFGFUKIPKſECPVN[FWTKPI (2007). Temperature data were used to Holocene (which began 10 000 years the past 1 000 years in Paraná State and map areas suitable for A. angustifolia. ago) (Klein, 1984). the past 1 500 years in The maps were developed using the In the dry and cold period before the State. geoprocessing program ArcGIS9. As last glacial maximum, 50 000 years ago, in the first model, linear regression was the vegetation was dominated by grass- CLIMATE VULNERABILITY used to relate temperature with latitude, lands and shrubs, with forests restricted MAPPING longitude and elevation. This second to deep valley refuges (Ledru et al., In the present study, two models were simulation predicted less reduction in the 1996). From 45 000 to 33 000 years used to predict the impact of different species’ distribution area (Figure 2).

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Ň5 Ň5 1 (de Sousa et al., 2005; Stefenon, Gailing Araucaria angustifolia and Finkeldey, 2008). geographic distribution in southern Brazil As trees have long life cycles, the pro- according to various cess of adaptation to changing conditions temperature scenarios is probably slower than the predicted rate of global climate change (Hamrick, 2004). GENETIC VARIATION AND Most of the negative genetic effects caused ADAPTATION by decline and fragmentation of popula- Understanding of the factors affecting tions of A. angustifolia are expected to the past and present distribution of a become evident only after several tree Current species is important for conservation generations (de Sousa, 2000). programmes. Responses of tree species Ň5 Ň5 to environmental change are complex. CONCLUSIONS Their ultimate survival will depend on Genetic variation is necessary for adap- seed dispersal and on their ability to tation of tree species and populations to reproduce successfully. Vulnerability environmental changes and is a precon- can be manifested in changes in flow- dition for conservation. More efficient ering and seed germination, reduced strategies for conservation, whether in regeneration success and diminished situ or ex situ, can be established only growth rates, and is often aggravated by based on knowledge about environmen- increased disturbance by fire and insects tal requirements and variation patterns and increased competition from compet- of targeted species and forest types, Current + 1oC ing or exotic (introduced) vegetation. combined with future climate change The interaction of different stress factors scenarios. is difficult to predict. For A. angustifolia, Vulnerability mapping can be useful the main stress factors are water deficit to predict areas where climate change and high temperatures. will have drastic effects on given tree Genetic variability in adaptive traits is species or populations, so they can be required for a species or tree population prioritized for germplasm collection and to withstand adverse environmental con- ex situ genetic conservation activities. ditions. Maintenance of genetic diversity However, more climate variables and is thus important for adaptation to new different climate models should be used environments. Population variability to improve future maps. studies using molecular genetic tools Matching information on genetic vari- o Current + 2 C are now enhancing understanding of the ability of tree species and populations genetic diversity status of key species with climate maps may help support Arau- and tree populations. In A. angustifolia, caria conservation programmes. Special genetic variation is present both between monitoring programmes and increased populations (Kageyama and Jacob, 1980; attention to basic physiological research Shimizu and Higa, 1980; de Sousa, 2000) are needed for better prediction of the and within populations (de Sousa, 2000; species’ response to climate change. X de Sousa et al., 2005; Stefenon, Gailing and Finkeldey, 2008). Seed dispersal is limited, but pollen is dispersed over relatively long distances (Bittencourt and Sebbenn, 2007). Although natural o Current + 3 C regeneration in Araucaria species has Bibliography been reported to be poor in most areas Favourable (current: >700 m altitude) studied, levels of diversity in regenera- Behling, H. 2005. Late quaternary vegetation High: 2 785 m ting areas were still considered sufficient Unfavourable (current: <700 m altitude) dynamics in southern and southeastern Low: 1 m to ensure future survival of the species Brazil with a special focus on the Araucaria

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Ň5 Favourable (current: >700 m altitude)

High: 2 785 m Unfavourable (current: <700 m altitude) Low: 1 m

2010 2030 2050

Ň5 2 Araucaria angustifolia (KNQUQſC%KGPEKCUG.GVTCUFC7PKXGTUKFCFG Palaeoclimatology, Palaeoecology, 123: geographic distribution in de Sao Paulo – Botânica, 10: 1–24. 239–257. southern Brazil according to various scenarios based Intergovernmental Panel on Climate Leite, P.F. 1994. As diferentes unidades on global climate models Change (IPCC). 2007. Climate change ſVQGEQNÎIKECU FC TGIKºQ UWN FQ $TCUKN 2007: impacts, adaptation and vulnerability. ŌRTQRQUVCFGENCUUKſECÁºQ. Master’s thesis, Contribution of Working Group II to the Federal University of Paraná, Curitiba, forests. In Resumos do 56o Congresso Fourth Assessment Report of the IPCC. Brazil. Nacional de Botânica. Curitiba, Brazil, Cambridge, UK, Cambridge University Leite, P.F., Klein, R.M. 1990. Vegetação. Congresso Nacional de Botânica. Press. In )GQITCſC FQ $TCUKN, Vol. 2, 4GIKºQ Bittencourt, J.V.M. & Sebbenn, A.M. 2007. Kageyama, P.Y. & Jacob, W.S. 1980. Sul, pp. 113–150. , Brazil, Patterns of pollen and seed dispersal in a Variação genética entre e dentro de (WPFCÁºQ+PUVKVWVQ$TCUKNGKTQFG)GQITCſC small, fragmented population of the wind- progênies de uma população de Araucaria e Estatística (IBGE). pollinated tree Araucaria angustifolia in angustifolia (Bert.) O. Ktze. In Forestry Reitz, R. & Klein, R.M. 1966. Araucariáceas. southern Brazil. Heredity, 99: 580–591. problems of the Araucaria, pp. 83–86. Itajaí, Brazil, Herbário Barbosa de Sousa, V.A. 2000. Population genetic Proceedings of the IUFRO Meeting on Rodrigues. studies in Araucaria angustifolia (Bert.) Forestry Problems of the Genus Araucaria, Shimizu, J.Y. & Higa, A.R. 1980. Variação O. Ktze. Göttingen, Germany, Cuvillier Curitiba, Brazil, 21–28 October 1979. genética entre procedências de Araucaria Verlag Göttingen. Curitiba, Fundação de Pesquisas Florestais angustifolia (Bert.) O. Ketz. In Forestry de Sousa, V.A., Sebben, A.M., Hartmer, do Paraná (FUPEF). problems of the genus Araucaria, pp. 78–82. H.H. & Zihe, M. 2005. Correlated mating Klein, R.M. 1984. Aspectos dinâmicos da Proceedings of the IUFRO Meeting on in populations of a dioecius Brazilian vegetação do sul do Brasil. Sellowia, 36: Forestry Problems of the Genus Araucaria, , Araucaria angustifolia (Bert.) O. 5–54. Curitiba, Brazil, 21–28 October 1979. Ktze. Forest Genetics, 12(2): 107–119. Ledru, M.P. 1993. Late quaternary Curitiba, FUPEF. Giraudo, A.R., Povedano, H., Belgrano, M.J., environmental and climatic changes in Stefenon, V.M., Gailing, O. & Finkeldey, Krauczuk, E., Pardiñas, U., Miquelarena, central Brazil. Quaternary Research, 39: R. 2008. Genetic structure of plantations A., Ligier, D., Baldo, D. & Castelino, M. 90–98. and the conservation of genetic resources 2003. Biodiversity status of the interior Ledru, M.P., Behling, H., Fournier, of Brazilian pine (Araucaria angustifolia). of Argentina. In C. Galindo- M., Martin, L. & Servant, M. 1994. Forest Ecology and Management, 255: Leal & I.G. Câmara, eds. The Atlantic Localisation de la forêt d’Araucaria du 2718–2725. forest of South America: biodiversity Brésil au cours de l’holocène – implications Veloso, H.P., Rangel Filho, A.L.R. & status, threats, and outlook, pp. 160–180. paléoclimatiques. Comptes Rendus de Lima, J.C.A. 1991. %NCUUKHKECÁºQ FC Washington, DC, USA, Island Press. l’Académie des Sciences, Séries III, XGIGVCÁºQDTCUKNGKTCCFCRVCFCCWOUKUVGOC Hamrick, J.L. 2004. Response of forest trees Sciences de la vie, 317: 517–521. universal. Rio de Janeiro, Brazil, IBGE. X to global environmental changes. Forest Ledru, M.P., Braga, P.I.S., Soubies, F., Ecology and Management, 197: 323–335. Fournier, M., Martin, L., Suguio, K. & Hueck, K. 1953. Distribuição e habitat Tuerc, Q. 1996. The last 50,000 years in the natural do Pinheiro-do Paraná (Araucaria Neotropics (southern Brazil): evolution of angustifolia). Boletim Faculdade de vegetation and climate. Palaeogeography,

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