0218-B4

Anatomical features of increment zones in different tree species in the State of São Paulo, Brazil

Mario Tomazello Filho ¹ , Claudio S. Lisi ¹ , Norbert Hansen ²

SUMMARY

Wood samples of 41 tree species from seven different sites (Savanna and Atlantic forest) in the State of São Paulo were analysed macro- and microscopically for occurrence of increment zones. Distinct increment zones were found in Bombax grandiflorum Cav., Chorisia speciosa St. Hil., Ocotea puberula (Reich.) Nees, Ocotea porosa (Nus & Mart.) Barroso, Copaifera langsdorfii Desf., Hymenaea courbaril L., Schizolobium parahyba (Vell.) Blake, Centrolobium sp. and Alchornea sidifolia Muell. Arg.. The anatomical features of increment zones of those nine species is described. In most cases, increment zones were marked by thick-walled and radially flattened latewood versus thin-walled earlywood fibres. However, marginal parenchyma bands were found to mark the boundaries, too. Tree species with a ring-porous or semi-ring-porous structure could not be found within the 41 trees species investigated. Distinct increment zones could be found in all leaf-fall categories. However, the occurrence of distinct increment zones seems to be more common in deciduous and semi-deciduous tree species.

INTRODUCTION

Tree ring research on tropical species nowadays is a known field of research. However, the knowledge about the existence of annual tree rings in tropical trees, which was already found at the beginning of the last century, was ignored by many scientists for a long time (Worbes 1989). During the last two to three decades different researchers doubtlessly demonstrated the existence of annual tree rings in many different tree species throughout the tropics (Vetter & Botosso 1989, Worbes 1989 & 1999).

However, it is also well known that tree ring analysis in the tropics is more difficult than in the temperated climate zones or in the boreal climate zone. From different investigations it is known that species with distinct increment zones can be found directly beside species with scarcely distinct or indistinct increment zones (Worbes 1999). According to Mariaux (1995), every tropical tree species has its own growth rhythm and reacts different to seasonal variations. The high variability of sites concerning climatic, edaphic and mechanic site factors and the complex anatomical structure of tropical woods are also reasons for the varying distinctness of increment zones.

The periodicity of increment zones in tropical trees, which does not have to be annual (Alvim 1964, Worbes & Junk 1989), also makes tree ring analysis more difficult. The occurrence of distinct increment zones in tropical trees is the first prerequisite for tree ring anylsis. However, knowledge about the periodicity of the increment zones is absolutelly essentiell. Different methods to proof the annual periodicity of increment zones are described in Worbes (1995).

In the present study, we investigated 41 tree species of different forests in the state of São Paulo. Aim of the investigation was to examine the wood anatomy in order to find tree species with distinct increment zones. The anatomy of the increment zones of those 9 tree species which showed distinct increment zones is described.

MATERIALS AND METHODS

Forthy-one tree species belonging to 22 families were sampled in 7 differents forests reserves and forest plantations in the State of São Paulo, Brazil. The locations of the different areas under investigation are shown in Map 1. All species are native in the State of São Paulo and grow either in the forest formations Savanna (Cerrado) or Atlantic forest (Mata Atlântica), described by Rizzini et al. (1988), Mittermeier et al. (1999).

Climate diagrams in all regions samples were collected, precipitation is well distributed throughout the year with an distinct dry season from June to August. Monthly precipitation in that time is less than 60 mm in all regions. In Piracicaba, mean annual precipitation for the 1975-2001 period was 1357 mm, mean annual air-temperature was 21.8 °C. With an average of 25°C, february was the hottest month, June and July were the coldest months with an average air-temperature around 17.7°C. The climate diagram of Piracicaba (1981-90 period) is shown in Fig. 1.

Wood samples were taken at breast height by a specially developed motorized borer (Cury 2002). The samples measuring 10 x 1.2 cm, including bark. For each of the 41 tree species investigated, three individuals were found and one sample collected out of each tree. Blocks of approximatelly 2 x 1 x 1 cm were cut out of one sample per species and softened by boiling in distilled water and glycerine. Transverse, tangential and radial sections (15 µm thick) were cut of the blocks using a sliding microtome and stained with safranin. Mikrofotographs of the transverse sections were made using a ZEISS Axioskop light microscope.

From each species, one or two samples were polished with sand paper (150 - 1200 grains per cm ² ) and observed with the naked eye. Images were scanned, using a HP ScanJet 6100C/T.

The leaf fall pattern of the species investigated were divided into deciduous, semi-deciduous and evergreen, based on the literature (Lorenzi 1992 & 1998, Morellato 1991) and phenological observations which were carried out monthly from January 1999 to Dezember 2001.

RESULTS

9 of the 41 tree species investigated showed distinct increment zones, 10 more species showed scarcly distinct increment zones. 13 species showed indistinct increment zones, while the remaining 9 species showed no increment zones. Distinct increment zones were found in all leaf-fall categories. However, whereas in each of the two categories deciduous and semi-deciduous 4 tree species with distinct increment zones could be found, in the categorie evergreen only one species showed distinct increment zones. The sampling was made up of 15 deciduous, 15 semi-deciduous and 11 evergreen species. Species with scarcely distinct and indistinct increment zones were found in all leaf-fall categories, too.

The structure of the increment zones of those nine tree species which showed distinct increment zones is described below:

Bombacaceae

Both species of the familie Bombacaceae studied in the scope of this investigation had distinct increment zones. The increment zones in Bombax grandiflorum Cav. (Fig. 2) as well as in Chorisia speciosa St. Hil. (Fig. 3) were marked by marginal parenchyma bands and thick-walled and radially flattened latewood versus thin-walled earlywood fibres. Furthermore, in both species the increment zones showed distended rays.

Lauraceae

The two Ocotea species investigated (Ocotea puberula (Reich.) Nees (Fig. 4) and Ocotea porosa (Nus & Mart.) Barroso (Fig. 5)) had distinct increment zones, marked by thick-walled and radially flattened latewood versus thin-walled earlywood fibres.

Leguminosae-Caesalpiniaceae

From the six species of the family Leguminosae-Caesalpiniaceae investigated, Copaifera langsdorfii Desf., Hymenaea courbaril L. and Schizolobium parahyba (Vell.) Blake had distinct increment zones. Cassia ferruginea Schrad. and Caesalpinia ferrea Mart. showed indistinct increment zones while Bauhinia forficata Link showed no increment zones. The increment zones in Schizolobium parahyba (Vell.) Blake (Fig. 6) were marked by thick-walled and radially flattened latewood versus thin-walled earlywood fibres. Copaifera langsdorfii Desf. (Fig. 7) and Hymenaea courbaril L. (Fig. 8) had increment zones marked by marginal parenchyma bands.

Leguminosae-Papilionoideae

Of all 41 tree species investigated, the species Centrolobium sp. (Fig. 9) showed the most distinct increment zones. They were marked by thick-walled and radially flattened latewood versus thin-walled earlywood fibres.

Euphorbiaceae

We investigated four tree species of the family Euphorbiaceae. Alchornea sidifolia Muell. Arg. (Fig. 10) was the only one were the increment zones were found to be distinct. Pachystroma ilicifolium Muell. Arg. showed scarcely distinct increment zones while Croton sp. and Securinega guarayuva Kuhlm. had no increment zones. The increment zones in Alchornea sidifolia were marked by thick-walled and radially flattened latewood versus thin-walled earlywood fibres.

DISCUSSION

Nine out of the 41 tree species investigated showed distinct increment zones. Four species belonged to the leaf-fall categorie deciduous, four to the categorie semi-deciduous and one to the categorie evergreen. It is known that evergreen tree species also can show distinct increment zones (Alvim 1964, Worbes 1999).

The increment zones in the two Ocotea species (Lauraceae) were marked by thick-walled and radially flattened latewood versus thin-walled earlywood fibres. Worbes (1989) allready mentioned, that this type of increment zone is common in species of the family Lauraceae. He also mentioned that terminal parenchyma bands are common in species of the family Leguminosae, which can be confirmed with the results of this study. Tree species with a ring-porous or semi-ring-porous structure, as can be found for example in Cedrela fissilis (Boninsegna et al. 1989), could not be found within the 41 trees species investigated. Worbes (1989) wrote, that this type of increment zone does not occur in tree species from the Central Amazonian inundation forests. Therefore, it looks like that this type of increment zone is not very common. Alves et al. (2000) investigated 491 tree species of the 22 most representative families of the Brazilian flora. They allready found that Ocotea puberula, Copaifera langsdorfii, Hymenaea courbaril and Centrolobium tomentosum showed increment zones.

According to Worbes (1995), the formation of increment zones in woody plants in general can be induced by seasonally changing favourable and unfavourable growth conditions. In the tropics, dry seasons and inundations were found to be triggering climate factors (Jacoby 1989, Worbes 1995). The relationship between precipitation and the formation of increment zones in tropical trees was found early. At the beginning of the last century Coster (1927 & 1928) recognized that trees of the same species showed distinct increment zones when they were grown under seasonal monsun climate, whereas individuals of the everwet climate only showed indistinct increment zones. According to Worbes (1995), a dry season width a length of two to three months and monthly precipitation with less than 60 mm can induce the formation of increment zones in tropical trees. In all areas under investigation in which trees were sampled in the scope of this study, precipitation is well distributed throughout the year with an distinct dry season of 3 months and monthly precipitation with less than 60 mm.

Luchi (1998) investigated the growth periodicity of Hymenaea courbaril in the State of São Paulo, using the method of cambial wounding (Wolter 1968, Shiokura 1989). He found that the growth rhythm is annual, triggered by the annual hydric deficit. Marcati (2000) investigated the growth rhythm of Copaifera langsdorfii. She also found an annual growth rhythm, triggered by the water regime. She found, that the cambial activity during the rainy season was higher and that an terminal parenchyma band was formed during the dry season.

The results of those two investigations already indicate that tree ring analysis in the eastern parts of the State of São Paulo, where precipitation is well distributed throughout the year, seems to be possible. However, even when it seems to be highly likely that the periodicity of the increment zones in other tree species which show distinct increment zones also will found to be annual, it should be proofed in further investigations. The results of this investigation indicate, that Bombax grandiflorum Cav., Chorisia speciosa St. Hil., Ocotea puberula (Reich.) Nees, Ocotea porosa (Nus & Mart.) Barroso, Copaifera langsdorfii Desf., Hymenaea courbaril L., Schizolobium parahyba (Vell.) Blake, Centrolobium sp. and Alchornea sidifolia Muell. Arg. are species which should be further investigated in terms of their potential for tree ring analysis.

AKNOWLEDGEMENTS

We thank the Estação Experimental de Santa Rita do Passa Quatro, Reserva Estadual de Porto Ferreira, Arboreto Experimental da DURATEX S.A., Estação Ecológica de Ibicatu, Estação Experimental de Tupi, Reserva Florestal Mata de Santa Genebra and the Sitio São Luiz for the samples. The financially supported by a research fellowship from the DAAD and FAPESP.

REFERENCES

Alves, E.S., V. Angyalossy-Alfonso. 2000. Ecological trends in the wood anatomy of some Brazilian species. 1. Growth rings and vessels. IAWA 21: 3 - 30.

Alvim, P. T. 1964. Tree growth periodicity in tropical climates. In: Zimmermann, M. H. 1964. The formation of wood in forest trees. Academic Press, New York, 479 - 495.

Coster, C. 1927. Zur Anatomie und Physiologie der Zuwachszonen- und Jahresringbildung in den Tropen. Annales Jardin Botanica Buitenzorg, 37: 49 - 160.

Coster, C. 1928. Zur Anatomie und Physiologie der Zuwachszonen- und Jahresringbildung in den Tropen. Annales Jardin Botanica Buitenzorg, 38: 1 - 114.

Cury, G. 2002. Descrição da estrutura anatômica do lenho e sua aplicação na identificação de espécies arbóreas do Cerrado e da Mata Atlântica do estado de São Paulo. Master thesis. University of São Paulo, ESALQ, Piracicaba.

Lorenzi, H. 1992. Árvores Brasileiras. Manual de Identificação e Cultivo de Plantas Arbóreas do Brasil. Ed. Plantarum, São Paulo Brazil.

Lorenzi, H. 1998. Árvores Brasileiras. Manual de Identificação e Cultivo de Plantas Arbóreas do Brasil Vol. 2. Ed. Plantarum, São Paulo Brazil.

Luchi, A.E. 1998. Periodicidade de crescimento em Hymenaea courbaril L. e anatomia ecológica do lenho de espécies de Mata Ciliar. Doctor thesis. University of São Paulo.

Marcati, C.R. 2000. Sazonalidade cambial em espécies tropicais. Doctor thesis. University of São Paulo.

Mariaux, A. 1995. Growth Periodicity in Tropical Trees - Foreword. IAWA 16: 327 - 328.

Maria, V.R.B. 2002. Estudo da periodicidade do crescimento, fenologia e relação com a atividade cambial de espécies arbóreas tropicais de florestas estacionais semideciduais. Master thesis. University of São Paulo, ESALQ, Piracicaba.

Mittermeier, R.A., N. Myers, C.G. Mittermeier. 1999. Hotspots. Earth's biologically richest and most endangered terrestrial ecoregions. CEMEX, S.A.. Mexico City.

Morellato, L.P.C. 1991. Estudo da fenologia de arvores, arbustos e lianas de uma floresta semidecidua no Sudeste do Brasil. Doctor thesis. University of Campinas.

Rizzini, C.T., A.F. Coimbra Filho, A. Houaiss. 1988. Brazilian ecosystems. EDITORA INDEX

Shiokura, T. 1989. A method to measure radial increment in tropical trees. IAWA Bull. n. s. 10: 147 - 154.

Vetter, R.E. & P.C. Botosso. 1989. Remarks on age and growth rate determination of Amazonian trees. IAWA Bull. n.s. 10: 133 - 145.

Walter, H. 1986. Vegetação e zonas climáticas: tratado de ecologia global. São Paulo, Ed. Pedagógica e Universitária.

Wolter, E. 1968. A new method for marking xylem growth. For. Sci. 14: 102 - 104.

Worbes, M. 1989. Growth rings, increment and age of trees in inundation forests, savannas and a mountain forest in the neotropics. IAWA Bull. n. s. 10: 109 - 122.

Worbes, M. 1995. How to measure growth dynamics in tropical trees - a review. IAWA 16: 337 - 351.

Worbes, M. (1999). Annual growth rings, rainfall-dependent growth and long-term growth patterns of tropical trees from the Caparo Forest Reserve in Venezuela. Journal of Ecology 87: 391 - 403.

Worbes, M. & W.J. Junk. 1989. Dating tropical trees by means of ¹⁴ C from bomb tests. Ecology 70: 503 - 507.

Map 1. Location of the seven research areas in the State of São Paulo, Brazil.

Information from Rizzini et al. (1988), the map also gives an idea about where the ecosystems savanna and Atlantic forest occur.

Fig. 1. Climate diagram of Piracicaba, São Paulo, Brazil, 1981-1990 period, (data from Walter 1986).

Fig. 2a-5b. Transverse sections. - 2: Bombax grandiflorum (Bombacaceae). - 3 : Chorisia speciosa (Bombacaceae). - 4: Ocotea puberula (Lauraceae). - 5: Ocotea porosa (Lauraceae). Figures named with the letter a are macrographs. - Scale bar = 1.5 mm. Figures named with the letter b are micrographs (magnification 100x). - Scale bar = 120 µm. The arrows indicate the increment zones.

Fig. 6a-9b. Transverse sections. - 6: Schizolobium parahyba (Leguminosae-Caesalpiniaceae). - 7 : Hymenaea courbaril (Leguminosae-Caesalpiniaceae). - 8: Copaifera langsdorfii (Leguminosae-Caesalpiniaceae). - 9: Centrolobium sp. (Leguminosae-Papilionoideae). Figures named with the letter a are macrographs. - Scale bar = 1.5 mm. Figures named with the letter b are micrographs (magnification 100x). - Scale bar = 120 µm. The arrows indicate the increment zones.

Fig. 10a,b. Transverse sections. - Alchornea sidifolia (Euphorbiaceae). a: macrograph. - Scale bar = 1.5 mm. b: micrographs (magnification 100x). - Scale bar = 120 µm. The arrows indicate the increment zones.

¹ Universidade de São Paulo, Departamento de Ciências Florestais,
ESALQ, Av. Pádua Dias 11, Caixa Postal 09, 13418-900 Piracicaba, SP, Brazil.
email: [email protected] and [email protected]

² Albert-Ludwigs-University Freiburg, Institute for Forest Growth,
Tennenbacherstr. 4, 79106 Freiburg, Germany.
email: [email protected]