Interciencia ISSN: 0378-1844 [email protected] Asociación Interciencia Venezuela Gabriel Christo, Alexandre; Guedes-Bruni, Rejan R.; Araújo P. Sobrinho, Felipe de; Gomes da Silva, Ary; Luna Peixoto, Ariane STRUCTURE OF THE SHRUB-ARBOREAL COMPONENT OF AN ATLANTIC FOREST FRAGMENT ON A HILLOCK IN THE CENTRAL LOWLAND OF RIO DE JANEIRO, BRAZIL Interciencia, vol. 34, núm. 4, abril, 2009, pp. 232-239 Asociación Interciencia Caracas, Venezuela Available in: http://www.redalyc.org/articulo.oa?id=33911575002 How to cite Complete issue Scientific Information System More information about this article Network of Scientific Journals from Latin America, the Caribbean, Spain and Portugal Journal's homepage in redalyc.org Non-profit academic project, developed under the open access initiative STRUCTURE OF THE SHRUB-ARBOREAL COMPONENT OF AN ATLANTIC FOREST FRAGMENT ON A HILLOCK IN THE CENTRAL LOWLAND OF RIO DE JANEIRO, BRAZIL AleXandre Gabriel Christo, Rejan R. Guedes-Bruni, Felipe DE AraÚjo P. Sobrinho, Ary Gomes DA SilVA and Ariane Luna PeiXoto SUMMARY The present study describes and evaluates the horizontal and ver- species with the greatest importance values (VI) were Aparisthmium tical structures of a lowland forest fragment on a hillock in the mu- cordatum, Guapira opposita, Lacistema pubescens, Xylopia sericea, nicipality of Silva Jardim, Rio de Janeiro State, Brazil (22o31’56’’S Tapirira guianensis and Piptocarpha macropoda. The high diversity and 42o20’46’’W). Twenty plots (10×2m) totaling 0.5ha were laid out observed was influenced by earlier anthropogenic actions and by the following the slope grade using DBH≥5cm as the inclusion criterion. current successional stage. The forest fragment studied demonstrated A total of 734 individuals were encountered, yielding a total density closer floristic similarity to areas inventoried in a close-by biologi- of 1468 ind./ha and a total basal area of 10783m2. The richness val- cal reserve than to fragments dispersed throughout the coastal plain. ues (129 species/41 families), Shannon-Wiener diversity (4.22) and Similarities in soil type, degree of soil saturation and use-history equitability (0.87) indices indicated an accentuated floristic hetero- of forest resources all support these relationships. The fragmented geneity and low ecological dominance. Lauraceae, Myrtaceae, Fa- physiognomy of the central lowland in this region and the use-his- baceae and Euphorbiaceae showed the greatest species richness, tory of the landscape make these small remnant forest areas impor- corroborating other studies that indicated these species as the most tant in terms of establishing strategies for landscape restoration and representative of Atlantic Forest areas in southeastern Brazil. The species conservation. fter five centuries of occu- (brick and tile manufacturing, residential ex- they are often swampy (Guedes-Bruni et pation and the effects of pansion, etc.). al., 2006a). various economic cycles, Within this historical The forests that cover the the Brazilian Atlantic Forest has been re- context, remnant tracts of lowland forests low hills are generally altered remnants of the duced to about only 7.6% of its original ex- in Rio de Janeiro State are now mostly native vegetation that existed before anthropo- tension (MMA, 1998). This drastic deforesta- limited to granite hillocks <300m in alti- genic processes dominated the lowland re- tion was driven by anthropogenic pressure on tude and to fluvial plains along the coast. gions around Rio de Janeiro. These low hills the forest, principally due to the selective ex- These low hills are surrounded by allu- are often totally deforested, but they are traction of valued arboreal species, agricul- vial forest areas that have been occupied sometimes covered by remnant forests of dif- tural expansion, lumbering and the use of by homes and agricultural plots due to ferent dimensions and in diverse successional wood as firewood by many industrial sectors their leveled topography, even though states. Cattle-raising is the most evident sign KEYWORDS / Atlantic Forest / Floristic Similarity / Lowland Forest / Structure / Received: 09/29/2008. Modified: 03/16/2009. Accepted: 03/18/2009. Alexandre Gabriel Christo. Agronomic Engineer. M.Sc. in Botany, Escola Nacional de Botâni- ca Tropical (ENBT), Brazil. Instituto de Pesquisas Jardim Botânico do Rio de Janeiro (JBRJ), Brazil. Address: Jardim Botânico do Rio de Janeiro, Rua Pacheco Leão, 915, 22.460-030 - Rio de Janeiro, RJ, Brazil. e-mail: [email protected]. Rejan R. Guedes-Bruni. Biologist. D.Sc. in Ecology, Universidade de São Paulo (USP), Brazil. Senior Researcher, JBRJ, Brazil. e-mail: [email protected]. Felipe de Araújo P. Sobrinho. Forest Engineer. M.Sc. in Botany, ENBT, Brazil. Doctoral stu- dent, USP, Brazil. e-mail: [email protected]. Ary Gomes da Silva. B.Sc. in Pharmacy. D.Sc. in Plant Biology, Universidade Estadual de Campinas (UNICAMP), Brazil. Professor, Centro Universitário Vila Velha, Brazil. e-mail: [email protected]. Ariane Luna Peixoto. Naturalist. D.Sc. in Plant Biology, UNICAMP, Brazil. CNPq Fellow, As- sociate Researcher, JBRJ, Brazil. e-mail: [email protected]. 232 0378-1844/09/04/232-08 $ 3.00/0 APR 2009, VOL. 34 Nº 4 of human intervention, and late all phytosociological pa- hand in hand with fire has rameters (Shepherd, 1995). determined the alteration of The 10 species with high- these landscapes and the spe- est VI were grouped into three cies growing there (Guedes- categories, pioneers, early sec- Bruni et al., 2006a). ondary and late secondary, ac- Although greatly frag- cording Gandolfi et al. (1995), mented, the lowland Atlan- and complemented on the basis tic Forest in the central re- of Paula et al. (2004) and Car- gion of Rio de Janeiro State valho et al., (2006a). is of great ecological im- To evaluate the horizontal portance, not only because structure of the vegetation, fre- of the species typical of this quency histograms of diameter vegetation formation but classes at 5cm intervals were also because it is the only elaborated for all individuals habitat of the Golden-Lion- encountered. The vertical struc- Tamarin (Leonthopitecus ture, as a characterization of rosalia Lesson, 1940), a the forest layers studied, was primate species endemic to evaluated based on the allo- this region and threatened Figure 1. Map of Rio de Janeiro State with studied area located. metric relationships between with extinction. diameter and height (log trans- Numerous authors have formed; Sneath and Sokal, contributed to the knowledge of the composi- PA, 1999) are divided, basically, between 1973), identifying the canopy with a dotted tion and floristic structure of this environ- Oxisols, Ultisols, Incepitsols (Aquepts). line as seen on the correlation diagram, and ment, which is characterized by extensive characterizing the canopy individuals as hav- fragmentation and a diversity of successional Methods ing a specified diameter and height, con- stages in the remnant areas (Guedes, 1988; firmed by verifying the first discontinuity Borém and Ramos, 2001; Borém and Olivei- Twenty plots (10×25m) among the points in the diagram (Guedes- ra-Filho, 2002; Carvalho et al., 2006a, were laid out along the line of the hill slope, Bruni, 1998). Guedes-Bruni et al., 2006a; Pessõa and Ol- covering a total sampling area of 0.5ha. In A graph was elaborated of iveira, 2006: Carvalho et al., 2007; and oth- laying out the plots a minimum distance of the vertical space occupied by the sampled ers). 20m was maintained from any trail so that, species that attained 75% of the VI. To deter- The present study describes essentially, only the central area of the frag- mine the minimum number of classes, as and evaluates the horizontal and vertical ment was sampled. All plants with trunk di- well as their amplitude, the formula proposed structure of a section of lowland forest grow- ameters at 1.3m above soil level (DBH) ≥5cm by Spiegel (1977) apud Lopes et al. (2002) ing on hillocks and provides information that were measured and identified. All testimonial was used. can contribute to conservation programs in material was deposited in the herbarium of Relationships of floristic the region. the Rio de Janeiro Botanical Garden (RB). similarity were sought between the study The taxonomic system adopted followed APG area and other forest fragments inventoried in Study area (2003). this coastal plain region. To that end, a pres- To elaborate a vegetation ence/absence matrix was elaborated of the The study area is part of profile, a 50×5m plot was established follow- species encountered in this study and com- the Santa Helena farm (22o31’56’’S and ing the slope of the hillock according to the bined with 17 other areas (totaling 279 spe- 42o20’46’’W; Figure 1), located along the BR methodology suggested by Melo (2002). The cies), eight of which were on private lands 101 federal highway in the municipality of profile diagram was elaborated in true height and nine of which were within the Rebio Silva Jardim (RJ), ~5km from the Poço das and diameter scales, using the AutoCAD Poço das Antas. The private lands are repre- Antas Biological Reserve (Rebio) in an area 2000 software program. sented by Fazendas Imbaú (Faz. Imb.), An- of Dense Ombrophilous Lowland Forest Sampling effort was meas- dorinhas (Faz. And.), Estreito (Faz. Est.), (IBGE, 1992). The forest fragment examined ured by determining the simple linear regres- Afetiva-Jorge (Faz. Aft.) and Sítio do Profes- covers 4.25ha and is surrounded by agricul- sion line (Zar, 1999) of the accumulation of sor (Faz. Stp.) reported by Carvalho et al., tural and grazing areas. The regional climate taxon richness (Whittaker, 1975) in regards to 2006a; Santa Fé (Faz. Sfe) from unpublished is classified as As by the Köeppen system: the accumulated number of observations data; and two topographic sequences at the rainy-tropical, with a winter dry season (Ber- (Loss and Silva, 2005), corresponding to the Biovert Agroflorestal farm: F.