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We investigated the interrelations between environmental variables (proxies for water availability and soil physico-chemical properties) and tree community patterns (diversity, composition and structure) along pond-upland topographic gradients within depressional watersheds in the upper Uruguay River basin in southern Brazil. Sampling plots were allocated in four topographic habitats: (1) inside ponds (wetland sites) and (2) immediately outside them, and in areas with (3) 60 cm and (4) 120 cm of elevation in relation to their limits (upland sites). Environmental conditions and forest composition varied along pond-upland gradients, but the diversity and structure of tree communities did not. Species turnover was associated with changes in topography-driven environmental conditions, notably water availability. Depressional watersheds show regionally unique abiotic and biotic features but are virtually unprotected by Brazilian private land legislation.

Understanding how wetland plant communities are organized in different ecosystems and spatial scales is essential to support conservation. Studies that have addressed this primary need, however, are exceptionally scarce. Here, we compared the diversity (alpha, beta and gamma) and composition of herbaceous and woody communities (treated separately and jointly) in ponds, streambanks and riverbanks in the upper Uruguay River Basin, southern Brazil. Results showed that each wetland ecosystem exhibited unique community patterns, depending on the plant group, data property (e.g., presence-absence or abundance), and community parameter. All ecosystem types had exclusive species, beta diversity explained by high rates of species turnover and balanced variation in abundance components, and particular floristic composition, revealing that each wetland type and site contributes fundamentally to the overall wetland plant diversity. These findings indicate that safeguarding wetland plant diversity depends on the adoption of holistic conservation measures.

AIM: Elucidate the potential impacts of climate changes on the distribution and conservation of the multiple habitats of the Mata Atlântica biodiversity hotspot, which are often treated as a unique entity in ecological studies. LOCATION: The whole extension of the South American Atlantic Forest Domain plus forest intrusions into the neighbouring Cerrado and Pampa Domains, which comprises rain forest (‘core’ habitat) and five environmentally marginal habitats, namely high elevation/latitude forest, rock outcrop habitats, riverine forest, semideciduous forest and restinga woodlands. TIME PERIOD: Current (2000) and future scenarios (2050 and 2070). MAJOR TAXA STUDIED: Tree species. METHODS: We modelled the responses of 282 diagnostic tree species, using multiple algorithms and distinct scenarios of climate change (828,234 projections). RESULTS: Potential loss of suitable environment summed 50.4% in semideciduous forest, 58.6% in riverine forest and 66% in rock outcrop habitats. Predictions for rain forest (12.2%), restinga woodlands (7.6%) and high elevation/latitude forest (5.2%) showed that overall loss of suitable environment will be relatively less severe for these habitats. Habitats that are confined to narrow edaphic conditions, namely rock outcrop habitats and riverine forest, are less studied and will likely suffer the greatest loss of biodiversity because their species are more dispersal limited. MAIN CONCLUSIONS: Because these habitats occupy distinct environmental conditions, lumping them in ecological analyses might lead to erroneous interpretations in studies aiming to evaluate the impacts of global change in the Mata Atlântica biodiversity hotspot. This reinforces the importance of our approach and urges for conservation strategies that account for habitat heterogeneity in the Mata Atlântica and other species‐rich environments.

The Program for Biodiversity Research (PPBio) is an innovative program designed to integrate all biodiversity research stakeholders. Operating since 2004, it has installed long-term ecological research sites throughout Brazil and its logic has been applied in some other southern-hemisphere countries. The program supports all aspects of research necessary to understand biodiversity and the processes that affect it. There are presently 161 sampling sites (see some of them at Supplementary Appendix), most of which use a standardized methodology that allows comparisons across biomes and through time. To date, there are about 1200 publications associated with PPBio that cover topics ranging from natural history to genetics and species distributions. Most of the field data and metadata are available through PPBio web sites or DataONE. Metadata is available for researchers that intend to explore the different faces of Brazilian biodiversity spatio-temporal variation, as well as for managers intending to improve conservation strategies. The Program also fostered, directly and indirectly, local technical capacity building, and supported the training of hundreds of undergraduate and graduate students. The main challenge is maintaining the long-term funding necessary to understand biodiversity patterns and processes under pressure from global environmental changes. Made available in DSpace on 2021-09-03T12:00:26Z (GMT). No. of bitstreams: 1 Program-for-Biodiversity-Research-2021.pdf: 4613827 bytes, checksum: 04b1875a6efdcba448fd73c1ecddf986 (MD5) Previous issue date: 2021

Pond systems perform a myriad of ecosystem services and make unique contributions to aquatic biodiversity conservation at the landscape scale. Despite their high conservation value, in Brazil, natural ponds have been lost and degraded at alarming rates. The remaining have become exceptionally vulnerable after the enactment of the recent Native Vegetation Protection Law (NVPL), whose unsustainable policies threatens to collapse these ecosystems. Although in force since 2012, the regulation of the NVPL is still in course at the state level, offering a unique opportunity to reduce the gap between science and policy. Here, we show why the NVPL threatens ponds and how its inadequacies can be overcome. Finally, we emphasize the need to create a national policy specifically focusing on wetland conservation.

We assessed the effectiveness of a protected area (PA) network in representing tree taxonomic and phylogenetic uniqueness in subtropical Atlantic Forests (Rain, Mixed and Seasonal Forests). Using a network of plots distributed over ∼95,000 km2 in southern Brazil, we first map the distribution of species richness (SR), beta diversity (BD) and phylogenetic diversity (PD) across the extent of remaining forest in the region. We then tested whether areas of taxonomic and phylogenetic uniqueness are either over- or under-protected based on the existing PA network (3% coverage) and at least 10% coverage, and assessed whether protection is distributed equally for each uniqueness area type. Here, areas of taxonomic uniqueness were defined as those with higher contribution than the mean to the total BD, and areas of phylogenetic uniqueness as those with higher or lower PD than expected by chance given their SR, and sites exhibiting spatial congruence or mismatch between PD and SR. We found a high percentage of representation of both areas of uniqueness across the extent of remaining forest. However, our analyses showed that these areas are poorly and unequally captured by the PA network; they are on average less protected than expected based on at least 10% coverage and have high inequality of protection. Our results suggest that both beta diversity and evolutionary history of angiosperm trees are not adequately protected, and indicate relevant areas to extend the current PA network. We also emphasize the need to consider a multifaceted approach to maximize protection of the Atlantic Forest biodiversity.

Although intraspecific trait variability (ITV) is known to decrease with the increasing spatial extent, few studies have addressed how it behaves accross different ecological scales alongside short environmental gradients and which factors drive this variation. We verify whether functional traits of a characteristic species of riverine forests exhibit greater inter- (regional scale) than intra-population (local scale) ITV and whether environmental factors are affecting its functional traits. We sampled four populations of Gymnanthes klotzschiana from different geomorphological regions in southern Brazil and collected data of leaf area (LA), leaf dry matter content (LDMC) and total height from seven adult individuals per plot. We observed significant differences among populations and greater variability at the inter- than intra-population scale for LDMC and total height. Leaf area exhibited greater intra-population variation. Cation exchange capacity and available phosphorus affected positively LDMC. Base saturation influenced negatively total height. Difference between mean canopy height and mean height of G. klotzschiana exerted negative effects on LDMC and total height and positive effetcs on LA. Our results demonstrate LDMC and total height to be suitable functional traits for studies on ITV at the regional scale and reinforce the need of considering it in ecological studies, including on a regional scale.

Subtropical forests certainly contribute to terrestrial global carbon storage, but we have limited understanding about the relative amounts and of the drivers of above-ground biomass (AGB) variation in their region. Here we assess the spatial distribution and drivers of AGB in 119 sites across the South American subtropical forests. We applied a structural equation modelling approach to test the causal relationships between AGB and environmental (climate and soil), structural (proportion of large-sized trees) and community (functional and species diversity and composition) variables. The AGB on subtropical forests is on average 246 Mg ha−1. Biomass stocks were driven directly by temperature annual range and the proportion of large-sized trees, whilst soil texture, community mean leaf nitrogen content and functional diversity had no predictive power. Temperature annual range had a negative effect on AGB, indicating that communities under strong thermal amplitude across the year tend to accumulate less AGB. The positive effect of large-sized trees indicates that mature forests are playing a key role in the long-term persistence of carbon storage, as these large trees account for 64% of total biomass stored in these forests. Our study reinforces the importance of structurally complex subtropical forest remnants for maximising carbon storage, especially facing future climatic changes predicted for the region.

Optimization of electrochemical methods for total antioxidant capacity (TAC) determination of Bunchosia glandulifera (Jacq.) Kunth (Malpighiaceae) extracts was performed. Other methods for antioxidant studies were also used for comparison with the results obtained by electrochemical assays. The extracts exhibited good solubility in the aprotic solvent dimethylsulfoxide. Hence, two electrochemical methods, namely cyclic (C) and differential pulse (DP) voltammetry (V) were optimized for TAC determination in this medium and by using ascorbic acid. The CV presented better linearity than DPV in the optimum conditions. TAC values determined by ABTS, FRAP and DPPH increased in the order seed

Questions What are the key environmental variables that influence the structure of riparian forests? Do disturbance (flooding) and stress (soil fertility) gradients result in functionally and phylogenetically different riparian forests? Do patterns of functional and phylogenetic diversity follow patterns of taxonomic diversity? Location Subtropical riparian tree community, Turvo State Park, Rio Grande do Sul state, southern Brazil. Methods We collected data on nine functional traits and assembled a phylogeny for all tree species found in a sample with 100 plots. We then modelled species richness and evenness, and functional and phylogenetic richness, evenness and divergence as functions of flooding frequency and soil fertility. Next, we used a three-table ordination method to look for associations between environmental conditions, the spatial locations of sampling sites and the distributions of species, trait values and lineages. We conducted these analyses for the entire area and separately for three habitats with different flooding frequencies. Finally, we tested for phylogenetic signal in functional traits. Results Species richness and evenness were highest under intermediate flooding frequency. In contrast, functional richness was negatively correlated with soil fertility, while phylogenetic richness increased with both flooding frequency and soil fertility (with phylogenetic evenness following a similar trend). Functional evenness was lowest under intermediate flooding frequency, and functional and phylogenetic divergence correlated in a complex quadratic way with both flooding and soil fertility. Functional traits were generally conserved in the phylogeny, although pioneer establishment strategy and resprouting capacity were convergent and strongly associated with frequent flooding. In contrast, the distribution of lineages was not associated with either environmental variables or site location. Conclusions There was a mismatch between taxonomic, functional and phylogenetic diversity patterns along disturbance and stress gradients. This mismatch likely occurs because functional traits involved in species sorting were either convergent or conserved in the phylogeny and because disturbance and stress gradients seem to differently affect each of the assessed diversity components. Even though disturbance seems to be the key driver of the structure of riparian tree communities, stress gradients (soil fertility) are the key predictors of important diversity components, especially functional richness. Thus, disturbance and stress gradients result in functionally and phylogenetically different riparian tree communities, leading to differences that cannot be predicted from differences in species richness and composition alone.

Aims We analyse here the variations in species composition and richness and the geographic ranges of the tree species occurring in South American subtropical Atlantic and Pampean forests. Our goals were to assess (i) the floristic consistency of usual classifications based on vegetation physiognomy, climate and elevation; (ii) the leading role of temperature-related variables on the variations in species composition and richness; (iii) the predominance of species with tropical–subtropical ranges, possibly as a result of forest expansion over grasslands after the Last Glacial Maximum (LGM); (iv) the restriction of most subtropical endemics to stressful habitats as a possible result of past forest refuges during the LGM. Methods

Understanding how species traits evolved over time is the central question to comprehend assembly rules that govern the phylogenetic structure of communities. The measurement of phylogenetic signal (PS) in ecologically relevant traits is a first step to understand phylogenetically structured community patterns. The different methods available to estimate PS make it difficult to choose which is most appropriate. Furthermore, alternative phylogenetic tree hypotheses, node resolution and clade age estimates might influence PS measurements. In this study, we evaluated to what extent these parameters affect different methods of PS analysis, and discuss advantages and disadvantages when selecting which method to use. We measured fruit/seed traits and flowering/fruiting phenology of endozoochoric species occurring in Southern Brazilian Araucaria forests and evaluated their PS using Mantel regressions, phylogenetic eigenvector regressions (PVR) and K statistic. Mantel regressions always gave less significant results compared to PVR and K statistic in all combinations of phylogenetic trees constructed. Moreover, a better phylogenetic resolution affected PS, independently of the method used to estimate it. Morphological seed traits tended to show higher PS than diaspores traits, while PS in flowering/fruiting phenology depended mostly on the method used to estimate it. This study demonstrates that different PS estimates are obtained depending on the chosen method and the phylogenetic tree resolution. This finding has implications for inferences on phylogenetic niche conservatism or ecological processes determining phylogenetic community structure.

Floods are frequently associated with disturbance in structuring riverine forests and they lead to environmental heterogeneity over space and time. We evaluated the distribution of tree species, ecological groups, species richness and diversity from the point bar to the slope of a riverside forest in southern Brazil (Lat. 30°01′S, Long. 52°47′W) to analyze the effects of flooding on soil properties and forest structure. A plot of 50 × 200 m divided in five contiguous transects of 10 × 200 m parallel to the river was installed, where we measured all the individual trees with pbh ≥ 15 cm. A detailed topographical and soil survey was carried out across the plot and indicated significant differences in organic matter and most mineral nutrients through the topographical gradient. The 1,229 surveyed individuals belonged to 72 species and 35 families. We used Partial CCA and Species Indicator Analysis to observe the spatial distribution of species. Both analyses showed that species distribution was strongly related to the flooding gradient, soil properties and also by space and pure spatial structuring of species and environmental variables (spatial autocorrelation), although a large part of variation remains unexplained. The ecological groups of forest stratification, plant dispersal and requirements for germination indicated slight differences among frequently, occasional and non-flooded transects. Species richness and diversity were higher at intermediate elevations and were associated to the increased spatial–temporal environmental heterogeneity. Across the plot, the direct influence of flooding on tree species distribution created a vegetation zonation that is determined by predicted ecological traits.

Apresentam-se os resultados de levantamentos florístico e fitossociológico em remanescente de Floresta Ombrófila Densa Submontana circunjacente à barragem do rio São Bento, objetivando fornecer dados primários para ações de restauração e conservação desta formação. A área está localizada no Sul de Santa Catarina, município de Siderópolis. Utilizou-se como área amostral um hectare e foram registrados indivíduos com DAP ≥ 5 cm e quantificados seus descritores estruturais. Foram identificadas 107 espécies, pertencentes a 42 famílias botânicas, totalizando 1.715 indivíduos. As espécies com maiores valores de importância (VI) foram Euterpe edulis Mart., Casearia sylvestris Sw. e Bathysa australis (St.-Hil.) K. Schum. Entre as espécies identificadas, encontrou-se elevado índice de zoofilia e zoocoria. Pela característica florística e abundância de serapilheira, a área encontra-se em estádio avançado de regeneração naturalAiming to provide primary data to be used in restoration programs, data from a floristic and phytosociological survey at a Submontane Ombrophilous Dense Forest remnant around São Bento river dam (Siderópolis municipality, Santa Catarina State, southern Brazil) are presented. All tree individuals with a diameter at breast height (DBH) ≥ 5 cm were recorded (1 ha plot). 1,715 individuals belonging to 107 species and 42 botanical families were identified. Euterpe edulis Mart., Casearia sylvestris Sw. and Bathysa australis (St.-Hil.) K.Schum. were the species with higher values of structural importance. High index of zoophily and zoochory were registered among the identified species. From the floristic composition and litter abundance, it can be assumed that the studied area corresponds to an advanced stage of natural regeneration

O objetivo do presente estudo foi realizar uma análise exploratória de padrões estruturais e de diversidade, relacionando-os com variáveis ambientais em uma área de floresta ribeirinha. A amostra 100 unidades amostrais (UAs), foi alocada nas margens do rio Uruguai, Parque Estadual do Turvo, Rio Grande do Sul (27º09' S e 53º53' W). Todos os indivíduos arbóreos com PAP >15 cm foram registrados. Para a descrição da vegetação foram estimados os principais parâmetros fitossociológicos, além do índice de diversidade de Shannon. Foram mensuradas variáveis ambientais edáficas, topográficas e a cobertura do dossel. As relações entre a abundância das espécies nas UAs e as variáveis ambientais foram avaliadas por meio de análises de correspondência canônica - CCA e CCA "parcial". Foram encontradas 82 espécies pertencentes a 30 famílias. A CCA exibiu um gradiente vegetacional nítido, relacionado hierarquicamente com a cota de elevação e, assim, com a suscetibilidade à inundação dos diferentes sítios. Três grupos de UAs foram delimitados por análise de agrupamento em função da cota de elevação e conseqüentemente suscetibilidade às inundações. Entre os grupos ocorreram diferenças estruturais, com maior área basal e altura máxima medianas nos sítios de elevação intermediária. A seletividade causada pelas inundações freqüentes sobre a composição de espécies modela a estrutura das áreas baixas, sendo a ausência de um dossel florestal típico, com no mínimo 10 m de altura, a característica mais expressiva. As áreas altas assemelham-se estruturalmente à floresta de interflúvio, compondo um trecho de transição. A diversidade medida pela riqueza específica e pelo índice de Shannon foi maior para áreas de elevação média, correspondendo com modelos existentes que associam a presença de um regime de distúrbios moderado, que gera maior heterogeneidade ambiental e, assim, diversificação de oportunidades para as espécies. We carried out an exploratory analysis of structural and diversity patterns and related them to environmental variables in a riverine forest. The sample, divided into 100 subplots, was placed on the banks of the Rio Uruguai, Turvo State Park, Southern Brazil (27º09' S; 53º53' W). All trees with the perimeter at breast height >15 cm were recorded. Vegetation description was based on phytosociological parameters and Shannon's diversity index. We measured edaphic and topographic environmental variables as well as canopy coverage. The relationship between species abundance in the subplots and environmental variables was assessed by canonical correspondence analysis - CCA and "partial" CCA. We found 82 species belonging to 30 families. The CCA showed a clear gradient, related hierarchically to mean elevation and thus to flooding susceptibility at different sites. Three groups of subplots were identified by cluster analysis based on mean elevation and flooding susceptibility. There were structural differences among these groups, with the highest basal area and maximum height medians at the middle elevation sites. Selectivity caused by frequent flooding on the species pool affects structure at the lower sites, with the most surprising difference being the lack of a typical forest canopy at least 10 m tall. On the other hand, the upper sites are structurally similar to interfluvial forest, thus constituting a transitional section. Diversity measured by species richness and by Shannon's index was higher for middle elevation sites. This pattern fits proposed models that relate moderate disturbance regime to the generation of environmental heterogeneity, and thus, opportunities of diversification for species.

Two 1 ha plots of a Southern Brazilian subtropical riverine forest, subject to different frequency and duration of floods, were compared to detect the differences in physiognomic structure, tree community composition, richness and diversity. Each plot was made up of 100 contiguous 10×10 m subplots, where 3451 trees with pbh ⩾15 cm were measured and identified. The survey observed 30 tree species, in the frequently flooded plot and 48 in the occasionally flooded plot. A detailed topographical and soil survey was carried out in both plots and indicated that the levels of organic matter and most mineral nutrients were higher in the frequently flooded stand. The forest understory was denser in the occasionally flooded stand which also showed taller emergent trees. Multivariate ordination and grouping techniques showed that the species’ abundance distribution was strongly related to the topographical variation. There was a clear pattern of species turnover according to topographic position, indicating that tree species developed different abilities to survive flooding events. As a result, the two plots also differed in their tree frequency per species regeneration, vertical distribution and dispersion groups. Both species richness and diversity decreased with increasing flood frequency, also showing a patchy distribution within both stands. At a local scale, flooding regime is regulating the spatial variation of α -diversity by forming different seral stages of predictable species composition. Compared to regularly flooded riverine and floodplain forests, riverine forests, with unpredictable flooding regimes, may show higher diversity at a local scale and more abundant opportunistic species of high environmental plasticity.

We examine the effects of forest fragmentation on the structure and composition of tree assemblages within three seasonal and aseasonal forest types of southern Brazil, including evergreen, Araucaria, and deciduous forests. We sampled three southernmost Atlantic Forest landscapes, including the largest continuous forest protected areas within each forest type. Tree assemblages in each forest type were sampled within 10 plots of 0.1 ha in both continuous forests and 10 adjacent forest fragments. All trees within each plot were assigned to trait categories describing their regeneration strategy, vertical stratification, seed-dispersal mode, seed size, and wood density. We detected differences among both forest types and landscape contexts in terms of overall tree species richness, and the density and species richness of different functional groups in terms of regeneration strategy, seed dispersal mode and woody density. Overall, evergreen forest fragments exhibited the largest deviations from continuous forest plots in assemblage structure. Evergreen, Araucaria and deciduous forests diverge in the functional composition of tree floras, particularly in relation to regeneration strategy and stress tolerance. By supporting a more diversified light-demanding and stress-tolerant flora with reduced richness and abundance of shade-tolerant, old-growth species, both deciduous and Araucaria forest tree assemblages are more intrinsically resilient to contemporary human-disturbances, including fragmentation-induced edge effects, in terms of species erosion and functional shifts. We suggest that these intrinsic differences in the direction and magnitude of responses to changes in landscape structure between forest types should guide a wide range of conservation strategies in restoring fragmented tropical forest landscapes worldwide.

The relationships among floristic, structural and physiognomic variables of the tree component, flooding regime variations and soil fertility were investigated in a riparian forest fragment (ca. 43 ha) in the Rio Botucarai watershed near the confluence with the Rio Jacui, southern Brazil. All the trees with a dbh ≥ 15 cm were surveyed in 100 contiguous 10 × 10 m plots and soil chemical and textural variables were obtained from the analyses of 15 topsoil samples (0–20 cm depth) collected at different locations. The sample sites encompass all the topographic variation of the area. We used canonical correspondence analysis (CCA) to seek correlations between environmental variables and tree component distribution. The 1,547 surveyed individuals belonged to 30 species and 16 botanical families. The Shannon diversity index (H′) and the Pielou equability (J′) were 1.995 and 0.586 nats ind.−1, respectively. Sebastiania commersoniana, Casearia sylvestris, Eugenia uniflora and Eugenia hyemalis presented the highest importance values. Species’ densities chiefly correlated with site elevation, flooding regime and soil chemical fertility. The analyses of ecological categories (EC) revealed that most species are heliophylous and typical of early successional stages. Richness and diversity (P

A cobertura florestal no Rio Grande do Sul encontra-se fortemente reduzida e fragmentada e, na Serra do Sudeste, particularmente, muito pouco se sabe sobre a estrutura de suas florestas. A localizacao de um remanescente de floresta primaria nas encostas orientais permitiu a realizacao de um levantamento fitossociologico com o objetivo de descrever a estrutura do componente arboreo e estabelecer relacoes com outras florestas estacionais. Foram amostradas todas as arvores com DAP > 5 cm em uma area de 1 ha, subdividida em 100 parcelas de 10 × 10 m. Foram registrados 2.236 individuos, pertencentes a 69 especies, 55 generos e 34 familias. As familias que sobressairam em riqueza foram Myrtaceae, Lauraceae e Euphorbiaceae. A pequena contribuicao de Fabaceae nas florestas na Serra do Sudeste contrasta com sua importância em outras florestas estacionais no Rio Grande do Sul e no Brasil. Dentre as especies com os maiores valores de importância, destacaram-se Gymnanthes concolor Spreng., Esenbeckia grandiflora Mart. e Sorocea bonplandii (Baill.) W.C.Burger et al., pela elevada densidade, Sloanea monosperma Vell. e Ilex paraguariensis A.St-Hil., pela elevada area basal, e com valores intermediarios nesses parâmetros Myrsine umbellata Mart., Miconia rigidiuscula Cogn. e Calyptranthes grandifolia O.Berg. A diversidade especifica (H') foi estimada em 3,204 (nats) (J' = 0,757), um dos mais altos valores ja registrados para as florestas estacionais no Rio Grande do Sul e no mesmo contexto de diversidade encontrado para a formacao em outras regioes no Brasil.

de 1 ha. As variaveis ambientais foram classificadas em topograficas, quimicas e texturais do solo e de luminosidade. Correlacoes especie-ambiente foram obtidas por Analise de Correspondencia Canonica (CCA). Comparacoes floristicas foram realizadas por analise de agrupamento (UPGMA) e analise de correspondencia. A diversidade especifica foi considerada baixa, pois foram amostradas apenas 26 especies. A CCA evidenciou que as variaveis ambientais mensuradas possuem pouca influencia na distribuicao das especies, ressaltando assim sua adaptacao ao ambiente anoxico, fortemente limitante. Dados de similaridade demonstraram que o substrato turfoso age como um filtro ambiental adicional, alem do estresse hidrico, na composicao de especies nas formacoes turfosas/ brejosas. ABSTRACT - This study aimed to describe the diversity and structure of woody vegetation of a swamp forests on peat substrate in the southern state of Santa Catarina, correlating floristic data with environmental variables. Individuals with DBH

Piratini river floodplain (PRFP) is located in coastal region of Pampa biome in southern Brazil. Recently, the PRFP was considered as a priority area for biodiversity conservation in biome, inspite of the lack of knowledge about your natural resources. The aim of this study is to survey the vascular flora, describe, quantify and identify the main native and anthropic phytophysiognomies and discuss the relevance of these to information to biodiversity conservation in a regional scale in biome. The main phytophysiognomic types were identified in aerial photographs using basic criteria of remote sensing, with checks and corrections in the field, estimated the vegetation heights based in plant life-form categories, and assessed the condition of flooding and conservation status of each vegetation type. In forest communities floristic inventory has been conducted. We defined five native and three anthropic phytophysiognomies, that were subdivided into ten different floristic subtypes. The present cover of native forests in PRFR is 4,376.83 ha, the second major remnant area in coastal Pampa. In these forests, we sampled 199 vascular plant species distributed in 146 genera and 71 botanical families, some of them classified as threatened, with restricted distribution to the region or endemic. The main phytophysiognomies of coastal Pampa were found in the PRFP. These findings corroborate the statement made by the Ministry of Environment that PRFP is an area of high priority for conservationin the biome. Key words: floristic survey, floodplain, vascular flora, coastal plain, plant richness.

Aiming to provide primary data to be used in restoration programs, data from a floristic and phytosociological survey at a Submontane Ombrophilous Dense Forest remnant around Sao Bento river dam (Sideropolis municipality, Santa Catarina State, southern Brazil) are presented. All tree individuals with a diameter at breast height (DBH) ≥ 5 cm were recorded (1 ha plot). 1,715 individuals belonging to 107 species and 42 botanical families were identified. Euterpe edulis Mart., Casearia sylvestris Sw. and Bathysa australis (St.-Hil.) K.Schum. were the species with higher values of structural importance. High index of zoophily and zoochory were registered among the identified species. From the floristic composition and litter abundance, it can be assumed that the studied area corresponds to an advanced stage of natural regeneration

Diásporos são as unidades de dispersão das plantas e sua morfologia está relacionada a adaptações às estratégias de dispersão e estabelecimento. Neste estudo, foram avaliadas características morfológicas de diásporos de 64 espécies de árvores e arvoretas adaptadas ao consumo por vertebrados, no Parque Estadual de Itapuã, sul do Brasil, com o objetivo de relacionar características relevantes para a dispersão, como tamanho, formato e cor dos diásporos, com aspectos relacionados ao estabelecimento de plântulas, como massa e quantidade de sementes. Foram considerados dispersos por vertebrados aqueles diásporos que apresentaram estruturas carnosas. O comprimento médio dos diásporos das espécies analisadas foi 1,7 ± 1,67 cm (N = 1.402). Baseando-se em um diagrama de ordenação, produzido com o comprimento e massa dos diásporos e número e massa de sementes por diásporo, as espécies foram separadas em quatro grupos morfológicos. Espécies com poucas sementes por diásporo foram associadas à dispersão por aves, mamíferos ou estratégias mistas; a presença de muitas sementes de massa elevada foi associada à síndrome de mamaliocoria; e grande número de sementes de pequena massa e tamanho, à síndrome mista. O grupo com maior riqueza (35 espécies) foi aquele com diásporos pequenos e poucas sementes, potencialmente aptos à dispersão por aves e com maior proporção em massa de sementes por diásporo. Diaspores are the dispersal units of plants and their morphology is linked to dispersal and establishment strategies. In this study we evaluated diaspore morphology in 64 tree and treelet species adapted to vertebrate consumption at Parque Estadual de Itapuã, southern Brazil. Our aim was to relate features crucial to dispersal, such as diaspore length, shape and color, to features limiting establishment success, like mass and number of seeds. We considered vertebrate-dispersed diaspores to be those with fleshy structures. Average diaspore length for the species analyzed was 1.7 ± 1.67 cm (N = 1,402). Based on an ordination diagram using length and mass of diaspores plus number and mass of seeds per diaspore, we separated the species into four morphological groups. Species with few seeds per diaspore were linked to bird, mammal, or mixed dispersal strategies; species with high mass and many seeds per diaspore was an indication of mammal dispersal; and a high number of small, light seeds was associated with mixed syndrome strategists. The group with highest species richness (35 species) presented small diaspores and few seeds, most of them red or black in color, potentially adapted to bird dispersal and with a greater proportion of seed mass per diaspore.

A sinúsia herbácea terrícola ainda é pouco estudada em florestas tropicais e subtropicais, principalmente no que se refere a sua relação a fatores ambientais. O objetivo deste trabalho foi descrever a estrutura desta sinúsia em floresta estacional, no Parque Estadual do Turvo em duas estações do ano e relacioná-la ao grau de abertura do dossel, medido pelo uso de fotografias hemisféricas. O levantamento de 30 unidades amostrais de 2 x 2 m resultou na amostragem de 29 espécies herbáceas, sendo 13 pteridófitas e 16 magnoliófitas. Lastreopsis effusa (Sw.) Tindale e Thelypteris scabra (C. Presl) Lellinger foram as espécies com maiores freqüências e coberturas. Didymochlena truncatula (Sw.) J. Sm. obteve elevado valor de cobertura e Olyra humilis Nees e Pharus lappulaceus Aubl. alta freqüência. A média das alturas foi de 37 cm (s ± 27). A diversidade (H') estimada no verão foi de 2,771 (nats) e a equabilidade (J') de 0,823, não diferindo significativamente do inverno (P = 0,509), assim como a composição e a cobertura herbácea não diferiram entre as duas estações (P = 0,728). Houve correlação entre a cobertura absoluta por parcela e o grau de abertura do dossel (P = 0,005). As maiores riqueza e diversidade e o porte e a cobertura elevados, comparados com outros estudos no sul do Brasil, são conseqüências da descontinuidade do dossel desta floresta, que permite maior incidência de luz no sub-bosque. A variação não significativa na estrutura da sinúsia herbácea é um indício do baixo grau de deciduidade da floresta. The terrestrial herbaceous synusiae in tropical and subtropical forests is scarcely studied, mainly concerning its relationship to environmental factors. The aims of this study were to describe the structure of this synusiae in a seasonal forest, in " Parque Estadual do Turvo" , in two different seasons and to correlate it to the degree of canopy opening, assessed by hemispherical photographs. Sampling was accomplished in 30 plots of 2 x 2 m. The survey recorded 29 herbaceous species: 13 pteridophytes and 16 magnoliophytes. Lastreopsis effusa (Sw.) Tindale and Thelypteris scabra (C. Presl) Lellinger had the highest frequency and cover. Didymochlena truncatula (Sw.) J. Sm. had high cover and Olyra humilis Nees and Pharus lappulaceus Aubl., high frequency. Mean height was 37 cm (s ± 27). Species diversity (H') and evenness indexes (J') during the summer were 2.771 (nats) and 0.823, respectively. These indexes (P = 0.509), composition and herbaceous cover (P = 0.728) were not significantly different between summer and winter. A correlation was detected between the absolute cover for each plot and the degree of canopy opening (P = 0.005). Compared to other southern Brazilian areas, the high values of diversity, richness, size and cover are consequences of the discontinuous forest canopy, which allows high light incidence on the understory. The non significant variation on the structure of the herbaceous synusiae is indicative of low degree of deciduousness of this forest.

The tree flora of seasonally dry forests (SDTF) of eastern tropical and subtropical South America was investigated according to two main aspects: (a) the variations in floristic composition were analyzed in terms of geographical and climatic variables by performing multivariate analyses on 532 existing floristic checklists; and (b) the links among different seasonally dry forest formations, Amazonian forests and cerrados (woody savannas) were assessed. Analyses were performed at the species, genus and family levels. There was a strong spatial pattern in tree species distribution that only receded and allowed clearer climate-related patterns to arise when either the geographical range was restricted or data were treated at the genus and family levels. Consistent floristic differences occurred between rain and seasonal forests, although these were obscured by strong regional similarities which made the two foresttypes from the same region closer to each other floristically than they were to their equivalents in different regions. Atlantic rain and seasonal forests

A composição específica de florestas estacionais no Rio Grande do Sul é fortemente influenciada por dois contingentes florísticos diferentes, um coincidente com as florestas atlânticas do leste e outro com as florestas paranaense-uruguaias do oeste. Um levantamento fitossociológico de uma floresta central sul-rio-grandense foi realizado para detectar a estrutura comunitária do componente arbóreo e a participação local dos diferentes contingentes florísticos. Todas as árvores com DAP > ou = 5 cm foram registradas em uma área de 1 ha, subdividida em 100 unidades amostrais de 10 x 10 m. As espécies amostradas foram classificadas como amplas ou restritas, segundo suas distribuições geográficas, considerando as afinidades florísticas leste ou oeste. A densidade total por hectare foi de 1855 indivíduos, pertencentes a 23 famílias, 46 gêneros e 55 espécies. As famílias com maior riqueza específica foram Fabaceae e Myrtaceae. As espécies mais importantes foram Gymnanthes concolor Spreng., Euterpe edulis Mart., Sorocea bonplandii (Baill.) Burger, Lanj. & Boer, Pachystroma longifolium (Nees) I.M. Johnst. e Trichilia claussenii C.DC., acumulando 55,2% do total do valor de importância. A diversidade específica (H') foi estimada em 2,244 (nats). As espécies do oeste formam um contingente mais diversificado, geralmente ocorrendo como árvores do dossel ou emergentes. As espécies do leste constituem um contingente bem menos diversificado, porém com uma alta participação quantitativa como árvores de porte médio do sub-bosque. Aspectos gerais da composição e da estrutura sugerem a importância de árvores do dossel de florestas estacionais interiores como formadoras de ambientes favoráveis para diversas árvores do sub-bosque de florestas pluviais costeiras. Species composition of seasonal forests in Rio Grande do Sul is strongly influenced by two different floristic contingents, one coinciding with the eastern Atlantic forests and other with the western Paranean-Uruguayan forests. A phytosociological survey of a central South-Riograndean forest was carried out to describe the community structure of the tree component and the local participation of different floristic contingents. All trees with DBH > or = 5 cm were recorded in an area of 1 ha, subdivided into 100 square plots of 10 x 10 m. The sampled species were classified according to their geographic distribution into widespread and restricted to eastern or western floristic affinities. The total density per hectare were 1855 individuals, distributed into 23 families, 46 genera and 55 species. The families with highest species richness were Fabaceae and Myrtaceae. The most important species were Gymnanthes concolor Spreng., Euterpe edulis Mart., Sorocea bonplandii (Baill.) Burger, Lanj. & Boer, Pachystroma longifolium (Nees) I.M. Johnst. and Trichilia claussenii C.DC., performing 55.2% of the total of importance values. Species diversity (H') was estimated as 2.244 (nats). The western species form a more diversified contingent, generally occuring as canopy or emergent trees. The eastern species constitute a much less diversified contingent, however with a high quantitative participation as medium-tall trees of the forest understorey. General composition and structural features suggest the importance of canopy trees of interior seasonal forests as providing a suitable habitat for several understorey trees from coastal rain forests.

Eletroforese em gel de poliacrilamida das proteínas solúveis extraídas de sementes de doze espécies da tribo Diocleae, apresenta padrão qualitativo semelhante no que diz respeito às bandas correspondentes às lectinas, sugerindo a possibilidade de seu uso como marcadores taxonômicos.Polyacrylamide gel electrophoresis of the soluble proteins extracted from seeds of twelve species belonging to the tribe Diocleae showed substantive qualitative pattern similiarities between the bands correspondent to the lectins.