scholarly journals DINÂMICA DA FLORÍSTICA E DA ESTRUTURA HORIZONTAL EM UM FRAGMENTO DE FLORESTA OMBRÓFILA MISTA MONTANA

Nativa ◽  
2019 ◽  
Vol 7 (6) ◽  
pp. 748
Author(s):  
Mailson Roik ◽  
Afonso Figueiredo Filho ◽  
Tiago Grespan ◽  
Thiago Floriani Stepka ◽  
Rodrigo Otávio Veiga de Miranda

Este trabalho objetivou analisar as alterações na composição florística e estrutura horizontal em um fragmento de Floresta Ombrófila Mista, localizado na Floresta Nacional (FLONA) de Irati, Paraná, Brasil, assim como compará-lo quanto à florística e estrutura de outros fragmentos florestais localizados em FLONAs da região sul do país. Todos os indivíduos com diâmetro à altura do peito maior ou igual a 10 cm (DAP ≥ 10 cm) foram identificados e mensurados ao longo de nove anos. A floresta apresentou elevada riqueza de espécies ao longo do período de monitoramento e pequenas alterações em relação a sua composição florística e estrutura horizontal. As divergências florístico-estruturais entre os fragmentos utilizados para comparação com o presente estudo se devem principalmente à grande heterogeneidade intrínseca a esta fitofisionomia, como também ao aumento da dissimilaridade em função do distanciamento geográfico.Palavras-chave: análise multivariada; composição florística; fitossociologia; Floresta com Araucária. DYNAMICS OF FLORISTIC AND HORIZONTAL STRUCTURE IN A FRAGMENT OF MONTANE MIXED OMBROPHYLOUS FOREST ABSTRACT: The aim of this research was to analyze the changes on the floristic composition and horizontal structure in an Araucaria Forest fragment, located in the Irati National Forest (FLONA), Paraná State, Brazil, as well as comparing it to the floristic and structure of other forest fragments located in FLONAs of the southern region of the country. All the individuals with diameter at breast height equal or larger than 10 cm (DBH ≥ 10 cm) were identified and measured for nine years. The forest presented a high number of species during the monitoring period and few changes in floristic composition and horizontal structure. The floristic-structural divergences among the fragments used for comparison with the present study are mainly due to the great heterogeneity intrinsic to this phytophysiognomy, as well as to the increase of dissimilarity due to geographic distance.Keywords: Araucaria forest; floristic composition; multivariate analysis; phytosociology.

2018 ◽  
Vol 18 (4) ◽  
Author(s):  
Ivanete Teresinha Mallmann ◽  
Vinícius Leão da Silva ◽  
Jairo Lizandro Schmitt

Abstract: The Araucaria Forest is a unique plant formation, practically restricted to the Atlantic Forest biome, in the South and Southeast of Brazil. It is immensely fragmented and its area is reduced to a minimum fraction, from 13 to 2% of the original area, due to intense anthropic exploitation. Our study evaluated the richness and floristic composition of ferns and lycophytes within three Araucaria forest fragments, in Rio Grande do Sul, Brazil. For the floristic inventory, a parcel of 1 ha (100x100m) was demarcated inside three fragments, which were classified by size: large (246 ha - H1LF), medium (57 ha - H2MF) and small (5.2 ha - H3SF). Occurring species life forms and preferential substrates up to 4 meters above ground were recorded. In total, 55 species were catalogued, only two of which were lycophytes, distributed in 32 genera and 17 families. Considering the area of fragments, the recorded species richness has decreased, presenting greater numbers in H1LF (48), followed by H2MF (33), and H3SF (29). In the three sites, terrestrial substrate and the hemicryptophyte species life form predominated. We observed that one hectare of a larger forest fragment presented 65% more species than that of a smaller one, considering that the smaller fragment total area represents only 2% of the larger forest's area. On the other hand, one hectare of the smaller fragment contributed 17% to fern and lycophyte species conservation occurring in Brazilian Araucaria Forests, and 8% to the state of Rio Grande do Sul's total richness. The diverse heterogeneity and species composition grants floristic identity to each of the studied forest interiors. Our results highlight the need to include the botanical parameters here analyzed in management, conservation degree evaluation, and maintenance of Araucaria Forests plant biodiversity.


FLORESTA ◽  
2015 ◽  
Vol 45 (3) ◽  
pp. 497
Author(s):  
Silvana Manfredi ◽  
Juliano Pereira Gomes ◽  
Paula Iaschitzki Ferreira ◽  
Roseli Lopes da Costa Bortoluzzi ◽  
Adelar Mantovani

A busca do conhecimento sobre a expansão das florestas em relação aos ecossistemas associados (campestre e banhado) aborda a presença de fatores ambientais como o fogo e o pastejo, frequentemente descritos como determinantes dos processos ecológicos favoráveis à dinâmica sucessional. Dessa forma, objetivou-se verificar se existem diferenças na composição florística do interior de fragmentos florestais e entre setores de transição floresta-campo e floresta-banhado, bem como identificar espécies indicadoras para cada um desses ambientes. O estudo foi realizado em fragmentos florestais situados nos municípios de Bom Jardim da Serra e Lages (Coxilha Rica), onde foram instaladas duas parcelas permanentes de 50x50 m, subdivididas em setores de 10x10 m, categorizados em três setores: Floresta Ombrófila Mista, transição floresta x campo e transição floresta x banhado. Há dissimilaridade florística entre os fragmentos florestais dos locais e, também, entre os setores de transição (ecótonos). As espécies indicadoras dos ecótonos estão vinculadas ao estágio inicial da sucessão florestal, apresentando potencial para colonização do campo, podendo atuar no início do processo de expansão da fronteira florestal.AbstractFloristic dissimilarity and indicator species of Araucaria Forest and ecotones. The search for knowledge about the expansion of forests in relation to associated ecosystems (native grassland and wetland) addresses the presence of environmental factors such as fire and grazing, often described as determinants of ecological processes in favor of succession dynamics. The objective here was to verify if there are differences among the floristic composition of the interior of forest fragments and transition sectors of forest-native grassland and forest-wetland, as well as to identify indicator species for each of these environments. The research was conducted in forest fragments located in the municipalities of Bom Jardim da Serra and Lages (Coxilha Rica), SC, where we installed two permanent plots of 50x50 m, subdivided into sectors of 10x10 m categorized into three sectors: Araucaria Forest, forest transition x native grassland and forest x wetland transition. There is floristic dissimilarity between the local forest fragments and also between the transition areas (ecotones). The indicator species of ecotones are linked to early stages of forest succession, with potential for colonization of the field, they can operate in the start of the expansion of the forest boundary process.Keywords: Araucaria Forest; native grassland; wetland; succession.


FLORESTA ◽  
2015 ◽  
Vol 45 (3) ◽  
pp. 535 ◽  
Author(s):  
Raphaela Vilela Eiras e Paiva ◽  
José Hugo Campos Ribeiro ◽  
Fabricio Alvim Carvalho

Este estudo visou avaliar a composição florística, a fitossociologia e a diversidade de espécies do estrato regenerante arbóreo de um pequeno fragmento (0,5 ha) de Floresta Estacional Semidecidual, após 10 anos de abandono, no perímetro urbano do município de Juiz de Fora, MG, Brasil. Os indivíduos da regeneração arbórea (altura ≥ 1 m e DAP < 5 cm) foram amostrados em 25 parcelas aleatórias de 5 x 5 m. Foram amostrados 1224 indivíduos pertencentes a 40 espécies. Houve uma forte predominância (> 90%) de espécies de estágios sucessionais iniciais (pioneiras e secundárias iniciais). Como reflexo da forte dominância ecológica observada, exercida principalmente pela elevada densidade das espécies Dalbergia nigra e Siparuna guianensis, o valor do índice de diversidade de espécies de Shannon (H’ = 2,38) foi muito inferior aos valores encontrados para fragmentos florestais maduros. Mesmo sendo um fragmento pequeno, isolado e em estágio inicial de sucessão secundária, análises multivariadas (agrupamento e DCA) evidenciaram a formação de grupos florísticos e uma forte diferenciação no arranjo das espécies, evidenciando a heterogeneidade típica de florestas tropicais. Embora apresente uma baixa diversidade, esse fragmento urbano tem funções ecológicas e sociais importantes para a região, que carece de áreas verdes para a conservação da flora nativa.AbstractStructure, diversity and heterogeneity of regeneration stratum in an urban forest fragment after 10 years of forest succession. This research aimed to evaluate the floristic composition, phytosociology and species diversity of the regenerating woody stratum of a small fragment (0.5 ha) of Semideciduous Forest, after 10 years of abandonment, in the municipality of Juiz de Fora, MG, Brazil. All woody individuals (height ≥ 1 m dbh <5 cm) were sampled at 25 random plots of 5 x 5 m. We sampled 1224 individuals belonging to 40 species. There was a strong predominance (> 90%) of species of early successional stages (pioneer and early secondary). Reflecting the strong observed ecological dominance, exercised primarily by the high density of the species Dalbergia nigra and Siparuna guianensis, species diversity value (Shannon index H '= 2.38) was much lower than the values found for mature forest fragments in this region. Although a small fragment, isolated and in early stages of secondary succession, the multivariate analysis (cluster and DCA) revealed the formation of distinct floristic groups and a strong differentiation in the arrangement of the species, showing the tropical forests typical heterogeneity. Although it has a low diversity, this urban fragment has ecological and social importance to the region, that present lack of green areas to conserve the native flora.Keywords:  Phytosociology; multivariate analysis; gradient analysis; ecological groups.


2021 ◽  
Vol 3 (4) ◽  
Author(s):  
Josélia Rozanny Vieira Pacheco ◽  
Felipe Fajardo Villela Antolin Barberena

Vascular epiphytes are one of the most important forest components, contributing to microclimatic maintenance. These plants find ideal conditions for development in the Amazon due to the spatial heterogeneity and high temperature and humidity typical of this biome. In recent years, the Brazilian Amazon has undergone dramatic changes in its landscape, mainly due to the increase in deforestation and fire rates. We present here the floristic composition and analyze the community structure of epiphytic angiosperms of an urban forest fragment in Eastern Amazon. A total of 71 epiphytic individuals were recorded belonging to eight species and four families. Orchidaceae was the most representative family, corroborating the pattern for surveys of epiphytic diversity in the Neotropical region. Epiphytic species were found on 24 individuals of 10 tree species. The epiphytic importance value (IVe) was low for all species, except for Aechmea tocantina and Rhipsalis baccifera. Cactaceae was the family with the highest IVe. Most epiphytes were found in the crown of trees (83.1%). The diversity index of the fragment was H’ = 1.80 and the equity index was J= 0.87, reflecting the absence of highly dominant species. Conservation of urban forest fragments is necessary for the maintenance of epiphytic flora and ecosystem services.


2018 ◽  
Vol 1 (1) ◽  
pp. 20-41
Author(s):  
Valdecir Da Silva ◽  
Vera Lúcia da Silva ◽  
Válter Da Silva ◽  
Dimítri De Araújo Costa ◽  
Francisco De Assis da Silva ◽  
...  

Forest fragmentation favours the propagation of some arboreal primate species that can alter the floristic composition of a community. This process may be associated with the loss of seed dispersants. In this work we propose to identify if the presence of frugivorous primates of medium and large size (Sapajus flavius and Alouatta belzebul) can influence forest diversity and structure. Further, we ask if the size of the fragment affects the availability of resources for these primates. Three fragments were studied in the Atlantic Forest of the State of Paraíba, Brazil, located in the municipalities of Sapé, Mamanguape, Rio Tinto, and Mataraca. In each area 25 plots of 50 x 4 m were delimited, randomly distributed along trails and transects. All trees with chest-high circumferences (CAP) above 12 cm found within the plots were marked with ribbons, and numbered continuously. A total of 114 plant species were documented in the Pacatuba Forest, 79 in the Asplan Forest, and 97 in the “Guaribas” (Sema III) Biological Reserve (REBIO) Forest. According to the Chao and Jacknife estimators, the REBIO Guaribas Forest can present more species than recorded in the present investigation. Species Tapirira guianensis, Protium giganteum and Protium heptaphyllum are the most abundant in the Asplan, Pacatuba and Sema III Forests, respectively. In the REBIO Guaribas Forest, the Shannon diversity index was (H') = 3.75, the Alpha-Fisher index was = 26.57 and the Simpson index (1-D) was = 0.90. Pacatuba was the forest fragment with the highest index of diversity (H') = 375, Alpha-Fischer = 33.74 and Simpson (1-D) = 0.95. Pacatuba and REBIO Guaribas Forsts possess greater Beta diversity. The results suggest that local and historical factors possibly increase Beta diversity, contributing to the increase in resources used as food by primates. Therefore, the presence of primates of medium and large size in the Pacatuba Forest may affect the diversity of resources, contributing to the dispersion of large fruits and seeds. The presence of primates of medium and large size can thus contribute to the preservation of floristic diversity in forest fragments.


2012 ◽  
Vol 35 (2) ◽  
pp. 145-157 ◽  
Author(s):  
Pedro Higuchi ◽  
Ana Carolina da Silva ◽  
Tiago Sousa Ferreira ◽  
Sheila Trierveiler de Souza ◽  
Juliano Pereira Gomes ◽  
...  

2017 ◽  
Vol 10 (6) ◽  
pp. 1875
Author(s):  
João Da Luz Freitas ◽  
Raullyan Borja Lima e Silva ◽  
Adriano Castelo dos Santos ◽  
Francisco de Oliveira Cruz Júnior ◽  
Erick Silva dos Santos ◽  
...  

O objetivo deste estudo foi analisar a composição florística, diversidade, distribuição diamétrica e estrutura horizontal de fragmentos florestais de terra firme e várzea no trecho médio da Reserva Extrativista do Rio Cajari, município de Mazagão, estado do Amapá. As florestas apresentaram relevante riqueza e diversidade florística. Registraram-se 1068 indivíduos com DAP ≥ 9,5 cm, distribuídos em 29 famílias, 68 gêneros e 84 espécies. A distribuição diamétrica das árvores apresentou-se em forma de “J” invertido, conforme tendência natural das florestas heterogêneas. As famílias Fabaceae, Lecythidaceae, Malvaceae, Chrysobalanaceae e Lauraceae foram as mais representativas em número de espécies, sendo que as espécies com maior valor de importância foram Swartzia polyphylla, Caryocar glabrum, Hevea brasiliensis, Vatairea guianensis e Virola surinamensis. A ampliação dos estudos na Resex é necessária tanto para o auxílio na criação de seu plano de manejo quanto para a subsistência das populações que vivem dentro e no seu entorno. A B S T R A C T The objective of this study was to analyze the floristic composition, diversity, diametric distribution and horizontal structure of forest fragments of firm ground and lowland in the middle section of the Extractivist Reserve of the Cajari River, municipality of Mazagão, state of Amapá. The forests presented significant richness and floristic diversity. There were 1068 individuals with DBH ≥ 9.5 cm, distributed in 29 families, 68 genera and 84 species. The diametrical distribution of the trees was inverted "J", according to the natural tendency of the heterogeneous forests. The families Fabaceae, Lecythidaceae, Malvaceae, Chrysobalanaceae and Lauraceae were the most representative in number of species, being that the species with greater value of importance were Swartzia polyphylla, Caryocar glabrum, Hevea brasiliensis, Vatairea guianensis and Virola surinamensis. The expansion of the studies in Resex is necessary both for the aid in the creation of its management plan and for the subsistence of the populations that live inside and in its surroundings. Keywords: floristic composition, floristic diversity, species trees, horizontal structure.


FLORESTA ◽  
2017 ◽  
Vol 47 (4) ◽  
pp. 407
Author(s):  
Ângela Maria Klein Hentz ◽  
Ana Paula Dalla Corte ◽  
Carlos Roberto Sanquetta ◽  
Christopher Thomas Blum ◽  
Guilherme Camacho Cadori

The forest fragmentation is considered to be one of the main processes causing negative effects on biodiversity. Among its effects, it causes changes in the composition and diversity of forest species through the replacement of original species by other adapted for disturbance areas. Therefore, the objective of this research was to evaluate the impact of the edge effect over richness and abundance of tree species in an Araucaria Forest fragment in southern Brazil. Data from two plots of 1 hectare each submitted to annual inventories (since 1995) were used. Individuals with diameter at breast height (1.30 m) over 10 cm were measured, and their geographical coordinates were recorded. These individuals were plotted over a grid where the plots were divided into subplots of 10x100 m after the edge. In addition, the edge influence over mortality and ingrowth was assessed. The existence of influence over richness and abundance of tree individuals was observed, mainly in the region up to 30 m from the edge. The edge effect influences mainly the ingrowth in comparison to the mortality, and both plots responded differently to edge effects.Key words: forest fragmentation, Atlantic forest, floristic composition, ecological group, cluster analysis. ResumoEfeito de borda sobre uma comunidade arbórea em um fragmento de Floresta com Araucária no Brasil. A fragmentação das florestas é considerada um dos principais processos que causam efeitos negativos sobre a biodiversidade. Entre eles estão alterações na composição e diversidade de espécies florestais pela substituição de espécies originais por outras adaptadas a áreas de distúrbios. Dessa forma, o objetivo deste trabalho foi avaliar o impacto do efeito de borda sobre a riqueza e abundância de espécies arbóreas em um fragmento de Floresta com Araucária no sul do Brasil. Foram utilizados dados de duas parcelas de 1 hectare cada, coletados em inventários anuais (desde 1995). Os indivíduos com diâmetro à altura do peito (1,3 m) acima de 10 cm foram medidos, e suas coordenadas espaciais foram coletadas. Os indivíduos foram plotados em um grid de parcelas subdivididas em parcelas de 10x100 m após a borda. Além disso, o efeito de borda sobre o ingresso e mortalidade do indivíduo foi analisado. Também, foi observada a influência da borda sobre a riqueza e abundância de indivíduos, principalmente nos primeiros 30 m após a borda. O efeito de borda influenciou principalmente os ingressos, em comparação com a mortalidade, e as duas parcelas apresentaram diferentes respostas ao efeito de borda.Palavras-chave: fragmentação florestal, Mata Atlântica, composição florestal, grupos ecológicos, Análise de Cluster.


FLORESTA ◽  
2019 ◽  
Vol 49 (4) ◽  
pp. 793
Author(s):  
Yasmim Andrade Ramos ◽  
Bruno Aurélio Campos Aguiar ◽  
Marcos Vinicius Cardoso Silva ◽  
Renata Elaine Siqueira Matos ◽  
Maria Cristina Bueno Coelho ◽  
...  

This study shows the phytosociology and floristics of a Dense Ombrophilous Forest fragment under forest management in Portel city, Pará State. Six conglomerates were sampled, divided into secondary and tertiary plots totaling 120 sample units of 0.4 hectares each, in which all trees with diameter at breast height (130 cm above ground; DBH) above 10 cm were measured. These individuals were botanically identified, and evenness and floristic similarity were calculated. There were 3,586 individuals distributed in 42 families, 121 genera, and 174 species. Families Fabaceae, Lecythidaceae, and Sapotaceae were the ones that obtained the highest IVI and the highest representativity of individuals. Species Eschweilera coriacea (DC.) S.A.Mori, Vouacapoua americana Aubl., and Tetragastris altissima (Aubl.) Swart were the ones with the highest IVI. Among the ten highest results, we highlight Syzygiopsis oppositifolia Ducke and Manilkara dardanoi Ducke, with great potential for timber production. The Shannon diversity index averaged 3.83 between the plots, and the Pielou evenness averaged 0.84, showing that the area presents high floristic diversity and great potential for forest management activities.


FLORESTA ◽  
2014 ◽  
Vol 45 (2) ◽  
pp. 273 ◽  
Author(s):  
Angélica Dalla Rosa ◽  
Ana Carolina Silva ◽  
Pedro Higuchi ◽  
André Luiz Guidini ◽  
Fábio Rodrigues Spiazzi ◽  
...  

O objetivo do presente trabalho foi verificar a influência do efeito borda sobre a diversidade e a participação de diferentes guildas de regeneração em um fragmento florestal nativo em contato com reflorestamento de pínus. Para isso, foram amostrados o estrato arbóreo adulto (DAP - diâmetro à altura do peito ≥ 5 cm) e regenerante (altura maior que 15 cm e DAP < 5 cm) em cinco transeções de 20 x 100 m perpendiculares à borda do fragmento. Cada transeção foi subdividida em cinco subparcelas de 20 x 20 m, definindo-se os setores representando o gradiente borda-interior: 0-20 m, 20-40 m, 40-60 m, 60-80 m e 80-100 m. As espécies foram classificadas em guildas de regeneração: pioneira, clímax exigente em luz e clímax tolerante a sombra. Foram determinadas a diversidade (Índice de Shannon) e a abundância das guildas em cada setor e estrato. Os dados foram analisados pelo teste t de Hutcheson e teste de proporção. Enquanto que no estrato adulto não houve variações na diversidade ao longo do gradiente borda-interior, no componente regenerativo a maior diversidade foi observada na borda (0-20 m). Apenas no estrato adulto foram observadas variações na participação relativa das guildas, com maior concentração de indivíduos de pioneiras nos primeiros 40 m.Palavras-chave: Ecologia; fragmentação de hábitats; Floresta Ombrófila Mista. AbstractDiversity and regeneration guilds of tree species in an edge of a natural forest in contact with a pinus plantation. The objective of the present study was to verify the influence of edge-effect on diversity and regeneration guilds participation in a forest fragment in contact with a Pinus plantation. For this, the adult (dbh - diameter at breast height≥5 cm) and regenerative (height higher than 15 and dbh<5 cm) components were sampled in five, 20×100 m, transects perpendiculars to the edge of a fragment. Each transect was subdivided in five, 20×20 m, subplots, defining the following sectors representing the edge-interior gradient: 0-20 m, 20-40 m, 40-60 m, 60-80 m and 80-100 m. The species were classified according to the following regeneration guilds: pioneer, light demanding climax and shade tolerant climax. The diversity (Shannon Index) and guilds abundance in each sector were determined. The data were analyzed by Hutcheson t test and proportion test. While no variation was observed for the adult component, the highest of diversity was observed in the edge (0-20 m) for the regenerative component. Variations along the edge gradient of the relative participation of guilds were observed only for adults, with a concentration of Pioneer within the first 40 m.Keywords: Ecology; habitat fragmentation; Araucaria Forest.


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