Acessibilidade / Reportar erro
Original Article, Conservation of Nature • Floresta Ambient. 26 (1) • 2019 • https://doi.org/10.1590/2179-8087.026715   copy

Forests of the Iguaçu National Park: Structure, Composition, and Richness

Authorship SCIMAGO INSTITUTIONS RANKINGS

Abstract

Considering the importance of the Iguaçu National Park for the conservation of the Atlantic Forest and the absence of scientific or technical studies characterizing the ecology of forest species after seven and a half decades of its existence, a phytosociological survey of the arboreal vegetation was conducted to identify the various existing species and their successional stages. A total of 54 families, 135 genera, and 218 species were found in this survey. Euterpe edulis Mart. was the most frequently occurring species, which together with Aspidosperma polyneuron Müll. Arg., characterize the seasonal forests in the central and south regions of the park. In the north region, located 700 m asl, Araucaria angustifolia (Bertol.) Kuntze and Ilex paraguariensis A. St.-Hil. were observed along with some seasonal species, characterizing a transitional environment between seasonal and ombrophillous forests. In general, forests in the park were classified in advanced stages of ecological succession.

Keywords:
successional stages; cotone; semi-deciduous forests

1. INTRODUCTION

Aiming to avoid the complete deterioration of the Atlantic Forest Biome, laws have been enacted to ensure that degraded areas are recovered and the use of the remaining areas on farms is managed rationally. In addition, several protected units (UC) such as the Iguaçu National Park (INP) have been created.

Despite the effectiveness of surveillance and protection within the boundaries of the INP, numerous farms, residences, and sawmills had already been established there before the Park was created, mainly in its southwest region, where the vegetation was completely cleared for agriculture and livestock uses. In other areas, there was selective logging, leading to virtual disappearance of some of the prevailing species and reduction of the potential for natural regeneration in some places due to loss of the seed bank ( Ferreira, 1999 Ferreira LM. Revisão do plano de manejo do Parque Nacional do Iguaçu encarte 5, com vistas à revisão do plano de manejo. Brasília: IBAMA: FUPEF; 1999. ).

In this context, the Park's first management plan of this UC called for detailed studies of the floristic structure and phytosociological and ecological successional stages of the vegetation in different regions. According to Ziller (1998) Ziller SR. Avaliação ecológica rápida do Parque Nacional do Iguaçu. Curitiba: IBAMA; 1998. , these studies would establish the structural patterns of vegetation and species occurrences, which would direct the management and recovery in areas where natural succession had been compromised.

In characterizing the structure of a forest, the number of trees and species distribution are directly associated with the growth habits of the species and environmental conditions of the site ( Lin et al., 2013 Lin G, Stralberg D, Gong G, Huang Z, Ye W, Wu L. Separating the effects of environment and space on tree species distribution: from population to community. PLoS One 2013; 8(2): e56171. http://dx.doi.org/10.1371/journal.pone.0056171. PMid:23409151.
http://dx.doi.org/10.1371/journal.pone.... ). The assessment of parameters of horizontal and vertical structure must also be observed in characterizing the structure, as well as the percentages of importance and coverage ( Mueller-Dambois & Ellenberg, 1974 Mueller-Dambois D, Ellenberg H. Aims and methods of vegetation ecology . New York: John Wiley e Sons; 1974. ).

After characterization of a particular forest area is performed, Meira & Martins (2002) Meira JAA No, Martins FR. Floristic composition of a montane seasonal semideciduous tropical forest in Viçosa MG Brasil. Revista Árvore 2002; 26(4): 437-446. advised that the comparative floristic aspect should be emphasized, wherein different remnants could have their floral compositions confronted or related by similarity index ( Ríos et al., 2010 Ríos RC, Galvão F, Curcio GR. Structure of main arboreal species in cruce caballero park and its floristic similarity with areas from Argentina and Brazil. Ciência Florestal 2010; 20(2): 193-206. ) or analysis grouping ( Avila et al., 2011 Avila AL, Araujo MM, Longhi SJ, Gasparin E. Agrupamentos florísticos na regeneração natural em remanescente de Floresta Ombrófila Mista, RS, Brasil. Scientia Forestalis 2011; 39(91): 331-342. ). Meira & Martins (2002) Meira JAA No, Martins FR. Floristic composition of a montane seasonal semideciduous tropical forest in Viçosa MG Brasil. Revista Árvore 2002; 26(4): 437-446. also mentioned that such methods enable observation of the floristic proximity between different forest formations, which is useful to the understanding of the Brazilian forest phytogeography.

The importance of the INP for the conservation of forest species in the Atlantic Forest and the absence of technical information after seven and a half decades of its existence substantiate this study, which was conducted in order to identify the forest species and succession stages of the different existing vegetation formations.

2. MATERIAL AND METHODS

Study area - The Iguaçu National Park (INP) is located in the western region of the state of Paraná and encompasses a total area of 185,262.50 hectares (ha). The geographic region occupied by the INP is characterized by Cfa climate ( Alvares et al., 2013 Alvares CA, Stape JL, Sentelhas PC, Gonçalves JLM, Sparovek G. Köppen’s climate classification map for Brazil. Meteorologische Zeitschrift 2013; 22(6): 711-728. http://dx.doi.org/10.1127/0941-2948/2013/0507.
http://dx.doi.org/10.1127/0941-2948/201... ). The terrain is determined by the Iguaçu River watershed and lies between 100 and 750 m asl as from the river bank. Bhering (2007) Bhering SB. Mapa de solos do Estado do Paraná: Escala 1:250.000 . Rio de Janeiro: Embrapa Solos; 2007. published the latest soil classification conducted in Parana state; for the region of the INP, the following classes have been identified: Ortic Rendzic Chernosol, Haplic Gleysol, Eutrophic Litholic Neosol, Red Disferric Latosol, Eutrophic Red Latosol, and Red Eutroferric Nitosol, with predominance of Nitosol and Latosol.

Forests in the INP are composed of different vegetation formations. Alluvial, Submontane and Montane formations of Semi-deciduous Forest (FES) predominate in the south and central regions and, in the north region, an ecotone between FES and Ombrophillous Mixed Forest (FOM), as well as Alluvial FOM are observed ( Souza et al., 2017 Souza RF, Machado SA, Galvão F, Figueiredo A Fo. Fitossociologia da vegetação arbórea do Parque Nacional do Iguaçu. Ciência Florestal 2017; 27(3): 853-869. http://dx.doi.org/10.5902/1980509828635.
http://dx.doi.org/10.5902/1980509828635... ).

Data and analysis - Seven groups of three plots were installed along the existing altitudinal gradient in the region from the Iguaçu River bank to the northernmost region of the Park. The plots were installed at intervals of 100 m asl in the West-East direction ( Figure 1 ). In total, 21 permanent plots were installed, each sampling plot comprising an area of 2,000 m2 (20 x 100 m) totaling 4.20 ha.

Figure 1
Localization of seven groups of plots installed in the Iguaçu National Park.

Plot groups consisted of three plots: group one consisted of plots 1, 2, and 3; group two was composed of plots 4, 5, and 6; and so on. Finally, group seven included plots 19, 20, and 21. At each elevation, plots were positioned at variable distances from each other and parallel to the river course. They were distributed along the drainage slopes from their base up to the plateau regions near the watershed boundaries.

All living trees with circumference ≥15.70 cm (DBH ≥5.00 cm) were included in the survey and their respective dendrologic materials were sent to the Botanical Museum of Curitiba for identification. The names were determined through a database search of the Missouri Botanical Garden (tropicos.org). Family classification followed the APG III (2009) The Angiosperm Phylogeny Group – APG III. An update of the Angiosperm Phylogeny Group classification for the orders and families of flowering plants: APG III. Botanical Journal of the Linnean Society 2009; 161(2): 105-121. http://dx.doi.org/10.1111/j.1095-8339.2009.00996.x.
http://dx.doi.org/10.1111/j.1095-8339.2... . Species were classified into Pioneer (PI), Light-Demanding Climax (CL), and Shade-Tolerant Climax (CS) according to adaptation from Oliveira-Filho et al. (1994) Oliveira-Filho AT, Vilela EA, Carvalho DA, Gavilanes ML. Effects of soils and topography on the distribution of tree species in a tropical riverine forest in south-eastern Brasil. Journal of Tropical Ecology 1994; 10(4): 483-508. https://doi.org/10.1017/S0266467400008178.
https://doi.org/10.1017/S02664674000081... to the system proposed by Swaine & Whitmore (1988) Swaine MD, Whitmore TC. On the definition of ecological species groups in tropical rain forests. Vegetatio 1988; 75(1-2): 81-86. http://dx.doi.org/10.1007/BF00044629.
http://dx.doi.org/10.1007/BF00044629 ... , and considering the bibliographies of Ziller (1998) Ziller SR. Avaliação ecológica rápida do Parque Nacional do Iguaçu. Curitiba: IBAMA; 1998. , Jarenkow & Waechter (2001) Jarenkow JA, Waechter JL. Composition, structure and floristic relations of the tree component of a seasonal forest in Rio Grande do Sul, Brazil. Brazilian Journal of Botany 2001; 24(3): 263-272. , Silva et al. (2008) Silva CPC, Oliveira-Filho AT, Van Den Berg E, Scolforo JR, Mello JM, Oliveira AD. Composição florística na floresta estacional semidecidual e floresta ombrófila. In: Scolforo JR, editor. Inventário florestal de minas gerais: floresta estacional semidecidual e ombrófila - florística, estrutura, diversidade, similaridade, distribuição diamétrica e de altura, volumetria, tendências de crescimento e áreas aptas para o manejo florestal. 3rd ed. Lavras: UFLA; 2008. , Gasper et al. (2013a) Gasper AL, Sevegnani L, Vibrans AC, Sobral M, Uhlman A, Lingner DV et al. Flora of the mixed ombrophyllous forest in Santa Catarina state, according of the forest and floristic inventory of Santa Catarina. Rodriguésia 2013a; 64(2): 201-210. http://dx.doi.org/10.1590/S2175-78602013000200001.
http://dx.doi.org/10.1590/S2175-7860201... , and Gasper et al. (2013b) Gasper AL, Uhlman A, Sevegnani L, Lingner DV, Rigon-Júnior MJ, Verdi M et al. Floristic and forest inventory of santa catarina: species of seasonal deciduous forests. Rodriguésia 2013b; 64(3): 427-443. http://dx.doi.org/10.1590/S2175-78602013000300001.
http://dx.doi.org/10.1590/S2175-7860201... , as well as to field observations. The species were also classified by vegetation formation based on the analysis of the distribution records of species available at Species Link (splink.org.br).

Vegetation sampling was conducted to ensure the observation of environmental changes in the INP, stratified into two levels so that all plots were installed in different environments. Even with the adoption of this sampling criterion, in order to verify the efficiency of the survey in relation to its floristic scope, a species-area curve was constructed to enable observation of the relationship between the number of species and the cumulative sampling effort ( Felfili et al., 2011 Felfili JM, Eisenlohr PV, Melo MMRF, Andrade LA, Meira JAA No. Fitossociologia no Brasil: métodos e estudos de casos. Viçosa: Editora UFV; 2011. ).

Characterization of the horizontal structure was performed by plot, in which 10 diameter classes with amplitude of 10 cm from the minimum diameter considered were arbitrarily defined to avoid an excessive number of classes to be grouped as trees with diameter ≥95 cm. To characterize the vertical structure, heights from the ground to the morphological inversion point of trees were measured using a retractable graduated rod, and were then distributed into 11 height classes with amplitude of 2 m from the ground surface.

Plots were classified into three succession stages: initial, intermediate, and advanced, according to the following attributes: species richness (S); dominance (DOA) (m2 .ha-1), density (DE) (trees.ha-1), and cover value (CV) for the ecological groups; horizontal and vertical structure of vegetation. Decisions were also subsidized by contributions reported by Whitmore (1989) Whitmore TC. Canopy gaps and the two major groups of forest trees. Ecology 1989; 70(3): 536-538. http://dx.doi.org/10.2307/1940195.
http://dx.doi.org/10.2307/1940195 ... , Schorn & Galvão (2009) Schorn LA, Galvão F. Dynamics of arboreal strate in three successional stages of a fragment of the atlantic rain forest in Blumenau, SC. Cerne 2009; 15(2): 221-235. , Holz et al. (2009) Holz S, Placci GP, Quintana RD. Effects of History of use on secondary forest regeneration in the Upper Parana Atlantic Forest (Misiones, Argentina). Forest Ecology and Management 2009; 258(7): 1629-1642. http://dx.doi.org/10.1016/j.foreco.2009.07.023.
http://dx.doi.org/10.1016/j.foreco.2009... , and Gasper et al. (2013b) Gasper AL, Uhlman A, Sevegnani L, Lingner DV, Rigon-Júnior MJ, Verdi M et al. Floristic and forest inventory of santa catarina: species of seasonal deciduous forests. Rodriguésia 2013b; 64(3): 427-443. http://dx.doi.org/10.1590/S2175-78602013000300001.
http://dx.doi.org/10.1590/S2175-7860201... . The CONAMA resolution no. 2 of 18 March 1994 ( Brasil, 1994 Brasil. Resolução Conama n. 2, 18 de Março de 1994 . Diário Oficial da República Federativa do Brasil, Brasília, DF (1994 mar). ) was observed for the ecological succession analysis despite not having been applied as a criterion for decisions.

Cover value for each ecological group was calculated by the following equation: CV = DR + DOA, where: DR refers to the ratio between the density obtained for the ecological group and the total density observed in the plot; DOA refers to the ratio between the dominance of each ecological group and the total dominance observed in the plot.

Aiming at a good floristic characterization of the forest, the tree species observed by Ziller (1998) Ziller SR. Avaliação ecológica rápida do Parque Nacional do Iguaçu. Curitiba: IBAMA; 1998. during a Rapid Ecological Assessment of the INP were added to the list. In this floristic survey, Ziller (1998) Ziller SR. Avaliação ecológica rápida do Parque Nacional do Iguaçu. Curitiba: IBAMA; 1998. visited observation points distributed throughout the Park. Likewise, as before, all botanical material was sent to the Botanical Museum of Curitiba for identification.

3. RESULTS

Floristic cover - In 10 plots, it was possible to sample 151 species, or 90% of the total. The remaining 11 plots contributed little to the increase in the number of species sampled, with addition of only 16 species, indicating that a large number of species occurred in common between the plots. In 20 plots, 100% of the species had already been sampled.

Floristic composition - Sampling of the plots showed occurrence of 4,299 trees that, when added to the species found by Ziller (1998) Ziller SR. Avaliação ecológica rápida do Parque Nacional do Iguaçu. Curitiba: IBAMA; 1998. , represented 54 botanical families, 135 genera, and 218 species ( Table 1 ). Two trees measured in the plots could only be identified at the family level, which were grouped and assigned to the family Myrtaceae. Another nine trees could not be identified due to absence of leaves caused by seasonality, and were assigned to the “Unknown” group. For the same reason, six species could only be identified by Ziller (1998) Ziller SR. Avaliação ecológica rápida do Parque Nacional do Iguaçu. Curitiba: IBAMA; 1998. at the genus level.

Thumbnail
Table 1
Floristic checklist of the tree species in the Iguaçu National Park with their classification in ecological groups (GE), vegetation formation, occurrence in plot groups, and registry by similarity to voucher specimens deposited in the Botanic Museum of Curitiba (MBM).

The most representative families in number of species were Fabaceae (34), Myrtaceae (18), and Lauraceae (16), followed by Euphorbiaceae, Meliaceae, Rutaceae, and Solanaceae with nine species each. The most frequent genera were Eugenia, Ocotea , and Solanum (seven), Nectandra (six), Inga , Lonchocarpus, and Trichilia (five), Casearia, Cordia, Ilex, and Zanthoxylum (four).

Considering only the sampling in the plots, the 10 species with the highest absolute density accounted for 44.96% of the total relative density: E. edulis (735), Sorocea bonplandii (241), Machaerium stipitatum (143), Nectandra megapotamica (137), Sebastiania brasiliensis, Cabralea canjerana and Ocotea diospyrifolia (134), Balfourodendron riedelianum (122), Chrysophyllum gonocarpum (104), and Syagrus romanzoffiana (92). The 10 species most commonly found in the plots and their respective frequencies (%) were O. diospyrifolia (100), N. megapotamica (95.24), C. gonocarpum (95.24), S. romanzoffiana, Campomanesia xanthocarpa and Chrysophyllum marginatum (90.48), S. bonplandii, M. stipitatum and C. canjerana (85.71), and B. riedelianum (80.95).

Among the 218 species listed, 13 were not classified into ecological groups and vegetation formation because they were not identified at the species level or were exotic. Among the 205 remaining species, 78 (38.05%) were classified as presenting FES characteristics, 17 (8.29%) as FOM, and 110 (53.66%) are of occurrence in both formations. Regarding successional stage, 70 species (34.15%) were classified as Shade-Tolerant Climax, 92 (44.88%) as Light-Demanding Climax, and 43 (20.98%) as Pioneer.

Successional stage - In general, high values of richness and dominance were recorded in the plots and, in some cases, an expressive range of diameters and predominance of climax species were observed ( Table 2 ). These results indicate that the forest remains well preserved.

Thumbnail
Table 2
Relative frequency (%) by diameter class, cover value for the ecological groups, and successional stage (SS) of plots installed in the Iguaçu National Park.

In plot 6, low values ​​of dominance and density were recorded (22.02 m 2.ha-1 and 675 trees.ha-1), attributed to the high occurrence of Chusquea Kunth. (Criciúma) and Cyathea sp. (Xaxim-bravo), as well as to the presence of canopy gaps opened by the falling of large trees.

The highest dominance and density values were observed in plot 12, associated with the presence of Aspidosperma polyneuron - the largest diameter class, Light-Demanding Climax species (Apuleia leiocarpa, Cabralea canjerana, Diatenopteryx sorbifolia, and Ficus luschnathiana) - 70, 80 and 90 diameter classes, and the high density of E. edulis and S. bonplandii - the first diameter class. Such a physiognomy is typical of seasonal forests with low levels of human disturbance.

The smaller diameter range observed in some plots suggested intermediate stages of succession. Hydromorphism was observed in the soil of plot 4, which limited the occurrence of large trees and justified its advanced successional classification. In plot 2, despite the limited range of diameter class (70 cm), the dominance value of 30 m2.ha-1 indicated vegetation in good conservation condition. In plots 8 and 9, located on the bottom of a drainage slope, presence of Guadua chacoensis (Taquaruçu) contributed to the low density values and their classification in intermediate stages.

Preserved forests present points of morphological inversion distributed in different strata, reaching expressive heights. This characteristic could be observed in all plots and, despite the positive asymmetry and negative kurtosis, the distribution curves extended to heights >13 m, as shown in Table 3 . The highest relative frequencies were found below nine meters, justified by the high density in the initial diameter classes and recurrence of Shade-Tolerant Climax species.

Thumbnail
Table 3
Relative frequency (%) by height class to the morphological inversion point for the 21 plots installed in the Iguaçu National Park.

Low frequency in the highest classes characterizes the emerging stratum above the relatively open canopy, typical of seasonal forests in southern Brazil ( Leite & Klein, 1990 Leite PF, Klein RM. Vegetação. In: Instituto Brasileiro de Geografia e Estatística – IBGE. Geografia do Brasil: região sul. Rio de Janeiro: IBGE; 1990. ). The most prevalent species in these classes were A. polyneuron, A. leiocarpa, B. riedelianum, Ceiba speciosa, Cordia trichotoma, Jacaratia spinosa, M. stipitatum, Myrocarpus frondosus, and P. rigida.

Presence of Araucaria angustifolia above 19 m was observed in plots 19, 20, and 21. This species is associated with P. rigida, Casearia decandra, and Nectandra lanceolata between 11 and 17 m, and the high density of C. canjerana, C. xanthocarpa, and Ilex paraguariensis in the understory, between 3 and 7 m, characterized the vertical structure of this transitional vegetation between FOM and FES. Specimens of emergent species in FES were identified within these plots in the classes of 7, 9, and 11 m, including A. polyneuron, C. trichotoma, and M. frondosus.

4. DISCUSSION

Floristic composition – Out of the 218 tree species listed, 51 were exclusive of the survey by Ziller (1998) Ziller SR. Avaliação ecológica rápida do Parque Nacional do Iguaçu. Curitiba: IBAMA; 1998. , 86 were exclusive of this survey, and 81 were common to both surveys. Ramos et al. (2008) Ramos VS, Durigan G, Franco GADC, Siqueira MF, Rodrigues RR. Árvores da floresta estacional semidecidual: guia de identificação de espécies . São Paulo: Edusp; 2008. identified 238 species in a FES remnant in Sao Paulo state and Silva & Soares-Silva (2000) Silva FC, Soares-Silva LH. Arboreal flora of the Godoy Forest State Park, Londrina, PR, Brazil. Edinburgh Journal of Botany 2000; 57(1): 107-120. http://dx.doi.org/10.1017/S096042860000007X.
http://dx.doi.org/10.1017/S096042860000... identified 206 species in a FES in northern Parana state; Gasper et al. (2013b) Gasper AL, Uhlman A, Sevegnani L, Lingner DV, Rigon-Júnior MJ, Verdi M et al. Floristic and forest inventory of santa catarina: species of seasonal deciduous forests. Rodriguésia 2013b; 64(3): 427-443. http://dx.doi.org/10.1590/S2175-78602013000300001.
http://dx.doi.org/10.1590/S2175-7860201... , identified 233 species between trees and shrubs in a Deciduous Forest in Santa Catarina state. Other researchers reported lower species richness in surveys conducted in smaller FES fragments in southern Brazil: Jarenkow & Waechter (2001) Jarenkow JA, Waechter JL. Composition, structure and floristic relations of the tree component of a seasonal forest in Rio Grande do Sul, Brazil. Brazilian Journal of Botany 2001; 24(3): 263-272. , Giehl & Jarenkow (2008) Giehl ELH, Jarenkow JA. Structural gradient of the tree component and relationship with flooding in a riverine forest, Rio Uruguai, southern Brazil. Acta Botanica Brasílica 2008; 22(3): 741-753. http://dx.doi.org/10.1590/S0102-33062008000300012.
http://dx.doi.org/10.1590/S0102-3306200... , Scipioni et al. (2011) Scipioni MC, Finger CAG, Cantarelli EB, Denardi L, Meyer EA. Phytosociological study in a forest fragment in the northwest of Rio Grande do Sul state. Ciência Florestal 2011; 21(3): 407-417. http://dx.doi.org/10.5902/198050983799.
http://dx.doi.org/10.5902/198050983799 ... , Ríos et al. (2010) Ríos RC, Galvão F, Curcio GR. Structure of main arboreal species in cruce caballero park and its floristic similarity with areas from Argentina and Brazil. Ciência Florestal 2010; 20(2): 193-206. , and Bianchini et al. (2003) Bianchini E, Popolo RS, Dias MC, Pimenta JA. Diversity and structure of a tree species community in flooded area in the municipality of Londrina, Southern Brazil. Acta Botanica Brasílica 2003; 17(3): 405-419. http://dx.doi.org/10.1590/S0102-33062003000300008.
http://dx.doi.org/10.1590/S0102-3306200... identified 55, 82, 72, 64 and 116 species, respectively.

In this research, the botanical families Fabaceae and Myrtaceae were the most representative in number of species, corroborating the studies by Oliveira-Filho & Fontes (2000) Oliveira-Filho AT, Fontes MA. Patterns of floristic differentiation among atlantic forest in southeastern Brazil and the influence of climate. Biotropica 2000; 32(4b): 793-810. http://dx.doi.org/10.1111/j.1744-7429.2000.tb00619.x.
http://dx.doi.org/10.1111/j.1744-7429.2... in an FES in southeastern Brazil and Jarenkow & Waechter (2001) Jarenkow JA, Waechter JL. Composition, structure and floristic relations of the tree component of a seasonal forest in Rio Grande do Sul, Brazil. Brazilian Journal of Botany 2001; 24(3): 263-272. in the central region of Rio Grande do Sul state. These families have also presented higher richness in surveys conducted in northern Parana state ( Silva & Soares-Silva, 2000 Silva FC, Soares-Silva LH. Arboreal flora of the Godoy Forest State Park, Londrina, PR, Brazil. Edinburgh Journal of Botany 2000; 57(1): 107-120. http://dx.doi.org/10.1017/S096042860000007X.
http://dx.doi.org/10.1017/S096042860000... ), northwestern Santa Catarina state ( Scipioni et al., 2011 Scipioni MC, Finger CAG, Cantarelli EB, Denardi L, Meyer EA. Phytosociological study in a forest fragment in the northwest of Rio Grande do Sul state. Ciência Florestal 2011; 21(3): 407-417. http://dx.doi.org/10.5902/198050983799.
http://dx.doi.org/10.5902/198050983799 ... ), Rio Grande do Sul state ( Giehl & Jarenkow, 2008 Giehl ELH, Jarenkow JA. Structural gradient of the tree component and relationship with flooding in a riverine forest, Rio Uruguai, southern Brazil. Acta Botanica Brasílica 2008; 22(3): 741-753. http://dx.doi.org/10.1590/S0102-33062008000300012.
http://dx.doi.org/10.1590/S0102-3306200... ), and in northeastern Argentina ( Ríos et al., 2010 Ríos RC, Galvão F, Curcio GR. Structure of main arboreal species in cruce caballero park and its floristic similarity with areas from Argentina and Brazil. Ciência Florestal 2010; 20(2): 193-206. ).

Other families common to the INP also reported by Jarenkow & Waechter (2001) Jarenkow JA, Waechter JL. Composition, structure and floristic relations of the tree component of a seasonal forest in Rio Grande do Sul, Brazil. Brazilian Journal of Botany 2001; 24(3): 263-272. , Silva & Soares-Silva (2000) Silva FC, Soares-Silva LH. Arboreal flora of the Godoy Forest State Park, Londrina, PR, Brazil. Edinburgh Journal of Botany 2000; 57(1): 107-120. http://dx.doi.org/10.1017/S096042860000007X.
http://dx.doi.org/10.1017/S096042860000... , and Ríos et al. (2010) Ríos RC, Galvão F, Curcio GR. Structure of main arboreal species in cruce caballero park and its floristic similarity with areas from Argentina and Brazil. Ciência Florestal 2010; 20(2): 193-206. include Lauraceae and Meliaceae, observed among the five richest families. In contrast, Oliveira-Filho & Fontes (2000) Oliveira-Filho AT, Fontes MA. Patterns of floristic differentiation among atlantic forest in southeastern Brazil and the influence of climate. Biotropica 2000; 32(4b): 793-810. http://dx.doi.org/10.1111/j.1744-7429.2000.tb00619.x.
http://dx.doi.org/10.1111/j.1744-7429.2... observed high species richness only for Lauraceae. Scipioni et al. (2011) Scipioni MC, Finger CAG, Cantarelli EB, Denardi L, Meyer EA. Phytosociological study in a forest fragment in the northwest of Rio Grande do Sul state. Ciência Florestal 2011; 21(3): 407-417. http://dx.doi.org/10.5902/198050983799.
http://dx.doi.org/10.5902/198050983799 ... and Giehl & Jarenkow (2008) Giehl ELH, Jarenkow JA. Structural gradient of the tree component and relationship with flooding in a riverine forest, Rio Uruguai, southern Brazil. Acta Botanica Brasílica 2008; 22(3): 741-753. http://dx.doi.org/10.1590/S0102-33062008000300012.
http://dx.doi.org/10.1590/S0102-3306200... reported richness only for Meliaceae, associated with early succession in the former study and with alluvial forest in the latter.

Meira & Martins (2002) Meira JAA No, Martins FR. Floristic composition of a montane seasonal semideciduous tropical forest in Viçosa MG Brasil. Revista Árvore 2002; 26(4): 437-446. performed a comparative analysis of similarity between fragments of montane FES in Minas Gerais state (between 650 and 800 m asl) and semideciduous forests in Sao Paulo and northern Parana states. Based on the results, the authors hypothesized that the floristic similarity between montane and submontane FES increases proportionally to latitude.

Comparison between the species that occurred in plots located in the submontane FES of the INP (between 100 and 600 m asl) identified 27 species in common with the study by Meira & Martins (2002) Meira JAA No, Martins FR. Floristic composition of a montane seasonal semideciduous tropical forest in Viçosa MG Brasil. Revista Árvore 2002; 26(4): 437-446. , apparently confirming their hypothesis. Some species even presented high density and dominance values, namely, C. gonocarpum, M. stipitatum, and S. bonplandii.

Also in support of the hypothesis of the aforementioned authors, high amplitude of dispersion along the altitudinal gradient was found for 52 seasonal species in the INP. These species are altitude indicators in the state of Sao Paulo, as described by Meira et al. (1989) Meira JAA No, Bernacci LC, Grombone MT, Tamashiro JY, Leitão HF Fo. Floristic composition of the semideciduous mountain forest of the Grota Funda Municipal Park, Atibaia, São Paulo. Acta Botanica Brasílica 1989; 3(2): 51-74. http://dx.doi.org/10.1590/S0102-33061989000200006.
http://dx.doi.org/10.1590/S0102-3306198... . Results of this analysis revealed 13 species occurring in the INP, 11 of which found in submontane FES: Alchornea triplinervia, Luehea divaricata, C. canjerana, Cedrela fissilis, C. decandra, Casearia obliqua, Allophylus edulis, C. speciosa, Handroanthus albus, Myrsine umbellata, and Pisonia ambigua. Cupania vernalis occurred only in montane regions 600 m asl, whereas Roupala brasiliensis was restricted to an ecotone between FES and FOM, 700 m asl.

Also corroborating this result, floristic similarity was observed between the montane FES (600-700 m asl) and the submontane Decidual Forests at higher latitudes below 550 m asl, as described by Jarenkow & Waechter (2001) Jarenkow JA, Waechter JL. Composition, structure and floristic relations of the tree component of a seasonal forest in Rio Grande do Sul, Brazil. Brazilian Journal of Botany 2001; 24(3): 263-272. and Scipioni et al. (2011) Scipioni MC, Finger CAG, Cantarelli EB, Denardi L, Meyer EA. Phytosociological study in a forest fragment in the northwest of Rio Grande do Sul state. Ciência Florestal 2011; 21(3): 407-417. http://dx.doi.org/10.5902/198050983799.
http://dx.doi.org/10.5902/198050983799 ... . Those studies found a total of 55 and 79 species, respectively, of which 30 (54.54%) and 42 (53.16%) were common to those of the present study.

Successional stage -Budowski (1965) Budowski G. Distribution of tropical american rain forest species in the light of successional processes. Turrialba 1965; 15(1): 40-42. reported that in dense undisturbed forests or in forests in more advanced successional stages, the recruitment of Pioneer species is subject to emergence of canopy gaps, which may explain the low cover value for this ecological group in the INP. Holz et al. (2009) Holz S, Placci GP, Quintana RD. Effects of History of use on secondary forest regeneration in the Upper Parana Atlantic Forest (Misiones, Argentina). Forest Ecology and Management 2009; 258(7): 1629-1642. http://dx.doi.org/10.1016/j.foreco.2009.07.023.
http://dx.doi.org/10.1016/j.foreco.2009... reported that the native forests of northeastern Argentina were mostly composed of Light-Demanding Climax and Shade-Tolerant Climax species, whereas Pioneer species accounted for 25%.

Shade-Tolerant Climax species are also widely recurrent and represented in greater abundance by E. edulis, S. bonplandii, Sebastiania brasiliensis , N. megapotamica, O. diospyrifolia, B. riedelianum, and C. gonocarpum, also in agreement with the results found by Holz et al. (2009) Holz S, Placci GP, Quintana RD. Effects of History of use on secondary forest regeneration in the Upper Parana Atlantic Forest (Misiones, Argentina). Forest Ecology and Management 2009; 258(7): 1629-1642. http://dx.doi.org/10.1016/j.foreco.2009.07.023.
http://dx.doi.org/10.1016/j.foreco.2009... . In the INP, this ecological group amounted to 100.53% of the total cover value for vegetation and, together with the Light-Demanding Climax species, to 183.68%.

Ziller (1998) Ziller SR. Avaliação ecológica rápida do Parque Nacional do Iguaçu. Curitiba: IBAMA; 1998. described the central region of the Park as showing fewer traces of anthropogenic activities, illustrated by the lush vegetation and high floristic diversity. Furthermore, in addition to A. polyneuron, other species characteristic of vegetation in advanced-stage seasonal forests were recurrent in this region, including A. leiocarpa , M. frondosus, B. riedelianum, Jacaratia spinosa, Lonchocarpus muehlbergianus, and Holocalyx balansae. Also noteworthy is the wide range of diameters observed in the plots established in that region (plots 7 to 18).

However, some of the plots located on the slopes of the river valley of the central region showed a narrower range of diameters and recurrence of Pioneer species at intermediate stages of ecological succession. This finding may be associated with the rugged terrain and increased water availability ( Muchailh et al., 2010 Muchailh MC, Roderjan CV, Campos JB, Machado ALT, Curcio GR. Methodology for planning fragmented landscapes aiming the creation of Ecological Corridors. Floresta 2010; 40(1): 147-162. ). Another related factor may be the increased light incidence in the understory of the plots located on the drainage slopes oriented to the East, resulting in an edge effect ( Schorn & Galvão 2009 Schorn LA, Galvão F. Dynamics of arboreal strate in three successional stages of a fragment of the atlantic rain forest in Blumenau, SC. Cerne 2009; 15(2): 221-235. ).

The narrower range of diameters and the high concentration of trees with morphological inversion point <7 m indicate intermediate successional stages for two plots in the southern and southwestern parts of the INP (plots 1 and 6). Ziller (1998) Ziller SR. Avaliação ecológica rápida do Parque Nacional do Iguaçu. Curitiba: IBAMA; 1998. pointed out that, unlike the logging that occurred in other regions, the anthropogenic activities in this region included clearing of vegetation for agricultural use, which slowed the restoration process to its original state.

Further North in the Park, in the transition zone between Semideciduous and Ombrophillous Forests, ecological succession proceeds at an intermediate stage, indicated by reduction in dominance, lower range of diameters, and lower morphological inversion point. This result can be explained by the high level of anthropogenic disturbance because of the forest proximity to the municipality of Santa Tereza do Oeste ( Ziller, 1998 Ziller SR. Avaliação ecológica rápida do Parque Nacional do Iguaçu. Curitiba: IBAMA; 1998. ). Despite the intensified logging activities occurred in this area, the vegetation was not completely removed, and thus maintained its potential for recovery. Evidence of this potential is observed in the presence of species of high commercial value typical of Ombrophillous Forests.

5. CONCLUSIONS

In general, forests in advanced successional stage were observed throughout the Iguaçu National Park (INP). The central region presents few characteristics indicative of anthropogenic activities and portrays, more accurately, the original seasonal forests that occurred in the Parana River basin. The forests of the South and far North areas of the INP still present signs of anthropogenic activities, where some species show low recurrence and depend on a long period of in disturbance and isolation to return to its original state.

Evidence of the effect of altitude and latitude on the distribution of species of seasonal forests was observed to compare the results of this survey with those of studies conducted in the Southeast and extreme South regions of Brazil.

ACKNOWLEDGEMENTS

The authors are grateful to Chico Mendes Institute for Biodiversity Conservation (ICMBio) for the authorization and availability of the physical structure to conduct this study, Coordination for the Improvement of Higher Education Personnel (CAPES) for the financial support in the form of a scholarship, and to National Council for Scientific and Technological Development (CNPQ) for the financial assistance to conduct the fieldwork.

  • FINANCIAL SUPPORT This study was funded by National Council for Scientific and Technological Development (CNPq), grant no. 484747/2011-8.

REFERENCES

  • Alvares CA, Stape JL, Sentelhas PC, Gonçalves JLM, Sparovek G. Köppen’s climate classification map for Brazil. Meteorologische Zeitschrift 2013; 22(6): 711-728. http://dx.doi.org/10.1127/0941-2948/2013/0507.
    » http://dx.doi.org/10.1127/0941-2948/2013/0507
  • Avila AL, Araujo MM, Longhi SJ, Gasparin E. Agrupamentos florísticos na regeneração natural em remanescente de Floresta Ombrófila Mista, RS, Brasil. Scientia Forestalis 2011; 39(91): 331-342.
  • Bhering SB. Mapa de solos do Estado do Paraná: Escala 1:250.000 . Rio de Janeiro: Embrapa Solos; 2007.
  • Bianchini E, Popolo RS, Dias MC, Pimenta JA. Diversity and structure of a tree species community in flooded area in the municipality of Londrina, Southern Brazil. Acta Botanica Brasílica 2003; 17(3): 405-419. http://dx.doi.org/10.1590/S0102-33062003000300008.
    » http://dx.doi.org/10.1590/S0102-33062003000300008
  • Brasil. Resolução Conama n. 2, 18 de Março de 1994 . Diário Oficial da República Federativa do Brasil, Brasília, DF (1994 mar).
  • Budowski G. Distribution of tropical american rain forest species in the light of successional processes. Turrialba 1965; 15(1): 40-42.
  • Felfili JM, Eisenlohr PV, Melo MMRF, Andrade LA, Meira JAA No. Fitossociologia no Brasil: métodos e estudos de casos Viçosa: Editora UFV; 2011.
  • Ferreira LM. Revisão do plano de manejo do Parque Nacional do Iguaçu encarte 5, com vistas à revisão do plano de manejo Brasília: IBAMA: FUPEF; 1999.
  • Gasper AL, Sevegnani L, Vibrans AC, Sobral M, Uhlman A, Lingner DV et al. Flora of the mixed ombrophyllous forest in Santa Catarina state, according of the forest and floristic inventory of Santa Catarina. Rodriguésia 2013a; 64(2): 201-210. http://dx.doi.org/10.1590/S2175-78602013000200001.
    » http://dx.doi.org/10.1590/S2175-78602013000200001
  • Gasper AL, Uhlman A, Sevegnani L, Lingner DV, Rigon-Júnior MJ, Verdi M et al. Floristic and forest inventory of santa catarina: species of seasonal deciduous forests. Rodriguésia 2013b; 64(3): 427-443. http://dx.doi.org/10.1590/S2175-78602013000300001.
    » http://dx.doi.org/10.1590/S2175-78602013000300001
  • Giehl ELH, Jarenkow JA. Structural gradient of the tree component and relationship with flooding in a riverine forest, Rio Uruguai, southern Brazil. Acta Botanica Brasílica 2008; 22(3): 741-753. http://dx.doi.org/10.1590/S0102-33062008000300012.
    » http://dx.doi.org/10.1590/S0102-33062008000300012
  • Holz S, Placci GP, Quintana RD. Effects of History of use on secondary forest regeneration in the Upper Parana Atlantic Forest (Misiones, Argentina). Forest Ecology and Management 2009; 258(7): 1629-1642. http://dx.doi.org/10.1016/j.foreco.2009.07.023.
    » http://dx.doi.org/10.1016/j.foreco.2009.07.023
  • Jarenkow JA, Waechter JL. Composition, structure and floristic relations of the tree component of a seasonal forest in Rio Grande do Sul, Brazil. Brazilian Journal of Botany 2001; 24(3): 263-272.
  • Leite PF, Klein RM. Vegetação. In: Instituto Brasileiro de Geografia e Estatística – IBGE. Geografia do Brasil: região sul Rio de Janeiro: IBGE; 1990.
  • Lin G, Stralberg D, Gong G, Huang Z, Ye W, Wu L. Separating the effects of environment and space on tree species distribution: from population to community. PLoS One 2013; 8(2): e56171. http://dx.doi.org/10.1371/journal.pone.0056171. PMid:23409151.
    » http://dx.doi.org/10.1371/journal.pone.0056171
  • Meira JAA No, Bernacci LC, Grombone MT, Tamashiro JY, Leitão HF Fo. Floristic composition of the semideciduous mountain forest of the Grota Funda Municipal Park, Atibaia, São Paulo. Acta Botanica Brasílica 1989; 3(2): 51-74. http://dx.doi.org/10.1590/S0102-33061989000200006.
    » http://dx.doi.org/10.1590/S0102-33061989000200006
  • Meira JAA No, Martins FR. Floristic composition of a montane seasonal semideciduous tropical forest in Viçosa MG Brasil. Revista Árvore 2002; 26(4): 437-446.
  • Muchailh MC, Roderjan CV, Campos JB, Machado ALT, Curcio GR. Methodology for planning fragmented landscapes aiming the creation of Ecological Corridors. Floresta 2010; 40(1): 147-162.
  • Mueller-Dambois D, Ellenberg H. Aims and methods of vegetation ecology . New York: John Wiley e Sons; 1974.
  • Oliveira-Filho AT, Fontes MA. Patterns of floristic differentiation among atlantic forest in southeastern Brazil and the influence of climate. Biotropica 2000; 32(4b): 793-810. http://dx.doi.org/10.1111/j.1744-7429.2000.tb00619.x.
    » http://dx.doi.org/10.1111/j.1744-7429.2000.tb00619.x
  • Oliveira-Filho AT, Vilela EA, Carvalho DA, Gavilanes ML. Effects of soils and topography on the distribution of tree species in a tropical riverine forest in south-eastern Brasil. Journal of Tropical Ecology 1994; 10(4): 483-508. https://doi.org/10.1017/S0266467400008178.
    » https://doi.org/10.1017/S0266467400008178
  • Ramos VS, Durigan G, Franco GADC, Siqueira MF, Rodrigues RR. Árvores da floresta estacional semidecidual: guia de identificação de espécies . São Paulo: Edusp; 2008.
  • Ríos RC, Galvão F, Curcio GR. Structure of main arboreal species in cruce caballero park and its floristic similarity with areas from Argentina and Brazil. Ciência Florestal 2010; 20(2): 193-206.
  • Schorn LA, Galvão F. Dynamics of arboreal strate in three successional stages of a fragment of the atlantic rain forest in Blumenau, SC. Cerne 2009; 15(2): 221-235.
  • Scipioni MC, Finger CAG, Cantarelli EB, Denardi L, Meyer EA. Phytosociological study in a forest fragment in the northwest of Rio Grande do Sul state. Ciência Florestal 2011; 21(3): 407-417. http://dx.doi.org/10.5902/198050983799.
    » http://dx.doi.org/10.5902/198050983799
  • Silva CPC, Oliveira-Filho AT, Van Den Berg E, Scolforo JR, Mello JM, Oliveira AD. Composição florística na floresta estacional semidecidual e floresta ombrófila. In: Scolforo JR, editor. Inventário florestal de minas gerais: floresta estacional semidecidual e ombrófila - florística, estrutura, diversidade, similaridade, distribuição diamétrica e de altura, volumetria, tendências de crescimento e áreas aptas para o manejo florestal 3rd ed. Lavras: UFLA; 2008.
  • Silva FC, Soares-Silva LH. Arboreal flora of the Godoy Forest State Park, Londrina, PR, Brazil. Edinburgh Journal of Botany 2000; 57(1): 107-120. http://dx.doi.org/10.1017/S096042860000007X.
    » http://dx.doi.org/10.1017/S096042860000007X
  • Souza RF, Machado SA, Galvão F, Figueiredo A Fo. Fitossociologia da vegetação arbórea do Parque Nacional do Iguaçu. Ciência Florestal 2017; 27(3): 853-869. http://dx.doi.org/10.5902/1980509828635.
    » http://dx.doi.org/10.5902/1980509828635
  • Swaine MD, Whitmore TC. On the definition of ecological species groups in tropical rain forests. Vegetatio 1988; 75(1-2): 81-86. http://dx.doi.org/10.1007/BF00044629.
    » http://dx.doi.org/10.1007/BF00044629
  • The Angiosperm Phylogeny Group – APG III. An update of the Angiosperm Phylogeny Group classification for the orders and families of flowering plants: APG III. Botanical Journal of the Linnean Society 2009; 161(2): 105-121. http://dx.doi.org/10.1111/j.1095-8339.2009.00996.x.
    » http://dx.doi.org/10.1111/j.1095-8339.2009.00996.x
  • Whitmore TC. Canopy gaps and the two major groups of forest trees. Ecology 1989; 70(3): 536-538. http://dx.doi.org/10.2307/1940195.
    » http://dx.doi.org/10.2307/1940195
  • Ziller SR. Avaliação ecológica rápida do Parque Nacional do Iguaçu Curitiba: IBAMA; 1998.

Publication Dates

  • Publication in this collection
    13 Dec 2018
  • Date of issue
    2019

History

  • Received
    15 Dec 2015
  • Accepted
    25 May 2018
Creative Common - by 4.0
This is an Open Access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.
Instituto de Florestas da Universidade Federal Rural do Rio de Janeiro Rodovia BR 465 Km 7, CEP 23897-000, Tel.: (21) 2682 0558 | (21) 3787-4033 - Seropédica - RJ - Brazil
E-mail: floram@ufrrj.br
Acompanhe os números deste periódico no seu leitor de RSS