Carlos Vellozo Roderjan

Fitossociologia do sub-bosque de uma Floresta Ombrófila Mista Aluvial,no município de Araucária, PR

This research is part of the work of the Barigui river’s floodplain forest (Barddal, 2002) and analyse the floristic and structure of the community’s understory, composed of shrub-arboreal individuals with perimeter at breast height (PBH) lower than 15 cm and up to 1,30 m height. Correlation of phytosociological parameters with the physiography, previously investigated, was also studied. Twenty plots of 25 m² were used, where the botanical species, height and diameter at base height (DBH) of each individual were evaluated. Among the 39 species found the most important was Allophylus edulis (A.St.-Hil., Cambess. e A. Juss.) Radkl. (vacum), that showed the largest parametric values and plasticity to ground water regime. It was inferred that possibly, artificial drainage was promoting the access of moderated and weakly tolerant flood species in these areas, originally composed of very specific flora.

Estrutura arbórea da Floresta Ombrófila Densa Altomontana de serras do Sul do Brasil

The aims of this study were: (1) to group information about the tree structure of the upper montane rain forest of Serra do Mar in the state of Parana (PR), Southern Brazil; and (2) to compare this information with available data from other mountain ranges in Southern and Southeastern Brazil. In the four mountain ranges studied, 2294 tree individuals (perimeter at breast height - PBH > 10 cm) were sampled, which included 28 families, 43 genera and 78 species. The cloud forest sampled in Serra Gigante showed the highest richness (41 species), followed by Serra da Prata (37), Serra da Igreja (34) and Serra do Ibitiraquire (26). The mean tree height was 4.8 m, the PBH was 22.9 cm, the tree abundance was 4779 in/ha, the basal area was 33.5 m2/ha and the Shannon diversity index was 2.68 nats/ind. Combining our data with the published data on the Serra do Mar region, resulting in a total of 11 surveys and 204 plots (10200 m2), a matrix with 75 identified species was obtained. In this matrix, the five most important species in the structure of the forest were Ilex microdonta, Siphoneugena reitzii, Drimys angustifolia, Ocotea porosa and Ilex chamaedrifolia. The cloud forests sampled in Serra do Mar showed lower richness and diversity indexes than the cloud forests in Serra da Mantiqueira (Southeast) and higher richness and diversity than cloud forests in Aparados da Serra Geral (South). These differences are possibly related to the anthropic influences, geographic distances, different centers of endemism, the tropical and subtropical surroundings, and geomorphology, among other factors.

Funcionalidades ambientais de solos altomontanos na Serra da Igreja, Paraná

Apesar de ainda existirem ecossistemas altomontanos no Parana em excelente estado de conservacao, iminentes ameacas antropicas e a fragilidade desses ambientes tem sido motivos de preocupacao. Este trabalho teve os seguintes objetivos: caracterizar solos de area representativa dos campos e florestas altomontanas ocorrentes na Serra da Igreja; apontar quais os possiveis fatores pedologicos que resultam nessas diferentes fitotipias; e caracterizar algumas das suas funcionalidades ambientais (estoque de C e de agua). Os principais solos encontrados nos campos foram Organossolos Folicos fibricos/sapricos (liticos e tipicos) e Organossolos Haplicos fibricos/sapricos (tipicos e terricos) e, nas florestas altomontanas, Gleissolos Haplicos aliticos tipicos. Ambas as classes sao de solos distroficos, extremamente acidos, com alta saturacao por Al trocavel e altos teores de C orgânico total. A distribuicao das florestas altomontanas esta fortemente controlada por vales e colos de cumeeiras, os quais estao sujeitos a processos morfogeneticos que resultam em solos com horizontes minerais. Ja os campos estao estabelecidos em topos, onde processos pedogeneticos promoveram espessamento de horizontes histicos, os quais, em funcao de suas caracteristicas intrinsecas, aliadas aos fortes ventos, parecem conter com sucesso o avanco da floresta sobre o campo. Os estoques de C por unidade de area nos solos dos campos sao superiores aos dos solos das florestas altomontanas, sendo ambos considerados altos quando comparados aos dados de outros ecossistemas, sendo duas a tres vezes maiores do que os encontrados em solos de ecossistemas de altitudes mais baixas na mesma latitude. Tambem foi constatada alta capacidade de retencao hidrica devido a porosidade total verificada nos horizontes histicos, os quais tem o potencial de reter em media 12 vezes seu volume em agua.

Relações entre a distribuição das espécies de diferentes estratos e as características do solo de uma floresta aluvial no Estado do Paraná, Brasil

Soil characteristics are the most important factors influencing species distribution in alluvial forests. Here we evaluated species composition, diversity and structure of three forest strata and their relationship with soil characteristics in a fragment of alluvial forest in the Iguacu River basin, Parana state. We asked if forest structure and diversity can be explained by edaphic and hydrological factors. We evaluated structural variables and floristic composition of three forest strata: regeneration stratum (20 cm 1.30 m; 20 subplots, 5 m×5 m) and upper stratum (pbh > 15 cm, 20 subplots, 10 m×10 m). In addition, we correlated species abundance with soil parameters in each subplot. The forest was characterized by a low diversity (Shannons index: regeneration stratum = 2.36; intermediate stratum = 2.49; upper stratum = 1.59) and high floristic similarity among strata (Sorensen index > 0.65). The relationship of species spatial distribution and soil characteristics was distinct among strata: species distribution was correlated with soil water-table levels and organic matter content in the upper stratum and with soil water-table levels and aluminum concentration in the intermediate stratum. On the other hand no significant correlation was verified in the regeneration stratum. Our results suggest that community structure and floristic composition in alluvial forests reflect different interactions during individual life cycles.

The Late Holocene upper montane cloud forest and high altitude grassland mosaic in the Serra da Igreja, Southern Brazil

Many soils of the highlands of Serra do Mar, as in other mountain ranges, have thick histic horizons that preserve high amounts of carbon. However, the age and constitution of the organic matter of these soils remain doubtful, with possible late Pleistocene or Holocene ages. This study was conducted in three profiles (two in grassland and one in forest) in Serra da Igreja highlands in the state of Paraná. We performed δ13C isotope analysis of organic matter in soil horizons to detect whether C3 or C4 plants dominated the past communities and 14C dating of the humin fraction to obtain the age of the studied horizons. C3 plants seem to have dominated the mountain ridges of Serra da Igreja since at least 3,000 years BP. Even though the Serra da Igreja may represents a landscape of high altitude grasslands in soils containing organic matter from the late Pleistocene, as reported elsewhere in Southern and Southeastern Brazil, our results indicate that the sites studied are at least from the beginning of the Late Holocene, when conditions of high moisture enabled the colonization/recolonization of the Serra da Igreja ridges by C3 plants. This is the period, often reported in the literature, when forests advanced onto grasslands and savannas.

Influence of Guadua paraguayana Döll on the structure and regeneration of a remaining forest at the high lands of Tibagi River, Paraná state.

As soon as the bamboo’s invasion was diagnosed in the alluvial floodplain of Tibagi’s river, Ponta Grossa-PR, the study started evaluating, through phytosociological study and indicators associated with the structure and functioning of the forest, the aggression and influence of the bamboo species on the structure and regeneration of a subtropical ombrophilous alluvial forest remnant. The phytosociological study was developed by an installation of sixteen plots (50m2) to inventory all the trees with CBH ≥ 15 cm and sixteen other plots (4m2) for studying the regeneration: individuals with up to 1.30 m high. The results show that the effect of G. paraguayana in species richness, mortality and number of trees, vitality of the remaining trees, abundance of vascular and nonvascular epiphytes, regeneration and in the incidence of radiation inside the plots, is very significant. But even though the changes caused by this bamboo compromise the regeneration dynamics of alluvial formations in the high Tibagi’s areas, the species is only an aggravating and not the cause of environmental degradation.

Fenologia vegetativa e reprodutiva de Schinus terebinthifolius Raddi (Anacardiaceae) em um fragmento de Floresta Ombrófila Mista Aluvial – Araucária (PR)

Eventos fenologicos vegetativos e reprodutivos de Schinus terebinthifolius foram avaliados por tres anos (2009-2012), em fragmento de Floresta Ombrofila Mista Aluvial, no municipio de Araucaria (PR). Schinus terebinthifolius e uma especie pioneira e de ampla distribuicao, inclusive naqueles ambientes considerados restritivos para a grande maioria das especies, como e o caso da maioria dos ambientes aluviais. O periodo de queda foliar da especie iniciou-se entre julho e agosto, e o de brotacao de folhas ocorreu em dois momentos: o primeiro de agosto a setembro, concomitante a queda foliar, e o segundo de janeiro a marco, periodo em que ocorreram as mais altas taxas de precipitacao. Nos aspectos reprodutivos, observou-se a floracao ocorrendo de outubro a novembro e a frutificacao de novembro a marco. O longo periodo de frutificacao pode ser uma das estrategias da especie que resultou na sua ampla distribuicao natural.