Florística e fitossociologia do componente arbóreo da transição Floresta Ombrófila Densa das Terras Baixas - Floresta Ombrófila Densa Submontana do Núcleo Picinguaba/PESM, Ubatuba, sudeste do Brasil

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Agricultural crops in the diet of bearded capuchin monkeys, Cebus libidinosus Spix (Primates: Cebidae), in forest fragments in southeast Brazil

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Variations in tree community composition and structure in a fragment of tropical semideciduous forest in southeastern Brazil related to different human disturbance histories

In an area of tropical seasonal semideciduous forest, the soil characteristics, floristic composition, physiognomic structure, and the distribution of three regeneration and three dispersal guilds were studied for four stands within the forest that had documented histories of varying degrees of human disturbance. The aim was to study forest regeneration in areas of preserved forest and secondary forest, with parts of both types of forest experiencing either 'intensive' or 'occasional' cattle trampling. The study was carried out in the Sebastiao Aleixo da Silva Ecological Station, Bauru, São Paulo State, Brazil. Two stands were called 'secondary' because they corresponded to forest tracts that were felled and occupied by crops and pastures in the past and then abandoned to forest regeneration ca. 40 years before this study. The other two stands, called 'preserved', corresponded to areas of the fragment where the forest has been maintained with only minor human impacts. The arboreal component of the tree community (diameter at breast height or dbh greater than or equal to 5 cm) was sampled in 20 plots of 40 m x 40 m, and the subarboreal component (diameter at the base of the stem or dbs < 5 cm and height greater than or equal to 0.5 m) in subplots of 40 m x 2 m. Physiognomic features, such as canopy height and density of climbing plants, were registered all over a 5 m x 5 m gridline laid on the sample plots. Soil bulk samples were collected for chemical and textural analyses. Most detected differences contrasted the secondary to the preserved forest stands. The soils of the secondary stands showed higher proportions of sand and lower levels of mineral nutrients and organic matter than those of the preserved stands, probably due to higher losses by leaching and erosion. Compared to the secondary stands, the preserved ones had higher proportions of tall trees, higher mean canopy height, lower species diversity, higher abundance of autochorous and shade-tolerant climax species, and lower abundance of pioneer and light-demanding climax species. Despite the high proportion of species shared by the preserved and secondary stands (108 out of 139), they differed consistently in terms of density of the most abundant species. on the other hand, the secondary and preserved stands held similar values for tree density and basal area, suggesting that 40 years were enough to restore these features. Effects of cattle trampling on the vegetation were detected for the frequency of trees of anemochorous and zoochorous species, which were higher in the stands under occasional and intensive cattle trampling, respectively. The density of thin climbers was lower in the stands with intensive trampling. (C) 2004 Elsevier B.V. All rights reserved.

Variação da massa específica da madeira de Eucalyptus grandis aos 8 anos de idade em função de diferentes níveis de produtividade

It were analyzed Eucalyptus grandis trees of 8 years old in the forest group of Duraflora S/A, with different annual increments based on volume, to the related studies of specific gravity values based on productivity indexes. The methodology used in analysis of specific gravity was the gamma-ray attenuation technique of Americium-241. The Eucalyptus grandis showed a specific gravity decreasing with the increasing of parcel productivity. For a gain of 3,5 m3 in productivity there was a decreasing of 1% in specific gravity. Nevertheless, it was not observed correlation between specific gravity and basal area in a same parcel. The present work stands out too, some of the difficulties found with relation to wood specific gravity determinations and emphasize the importance of take samples in the form of full rounded plates in three or four relative positions in the tree.

Comparison of the population structure of the fiddler crab Uca vocator (Herbst, 1804) from three subtropical mangrove forests

The population structure of U. vocator was investigated during a one-year period in three mangrove forests in southeast Brazil. The study specifically addressed comparisons on individual size juvenile recruitment and sex-ratio. The structure of the mangrove forests, i.e. density, basal area, and diameter, and the physical properties of sediments. i.e. texture and organic matter contents, were also examined. A catch-per-unit-effort (CPUE) technique was used to sample the crab populations using 15-min sampling periods by two people. Males always outnumbered females, probably due to ecological and behavioural attributes of these crabs. The median size of fiddler crabs differed among the sampled populations. The mangroves at Indaiá and Itamambuca showed higher productivity than those at Itapanhaú, where oil spills impacting the shore were reported. Marked differences were found regarding individual size, either their size at the onset of sexual maturity or their asymptotic size, suggesting that food availability may be favouring growth in the studied populations.

Regeneração natural de espécies da Mata Atlǎntica em sub-bosque de Eucalyptus saligna Smith. em uma antiga unidade de produção forestal no Parque das Neblinas, Bertioga, SP

This study aimed at characterizing the potential for natural regeneration of native vegetation in the under-story of an earlier Eucalyptus saligna Smith production stand. The study was carried out at the Parque das Neblinas, Bertioga municipality, SP, in a 45 ha third rotation stand; which had been abandoned 15 years ago for natural regeneration to occur. The sampling was done in 24 plots of 20 × 40 m. The sampled area was of 19,200 m2, with inventory made of 100% of the eucalyptus trees. All regeneration trees with a height ≥ 1.30 m and DBH ≥ 5.0 cm were measured, as well as adult individuals with DBH ≥ 5.0 cm; surveyed in two size classes. 1,417 individuals of E. saligna were measured, with a density of 738,02 individuals/ha and a basal area of 22.69 m2/ha. Among 2,763 natural regeneration individuals, 111 species belonged to 66 genera and 34 botanical families. The species represented 43.7% of the tree richness of neighboring native forest fragments. The total estimated density and the basal area were respectively 1,052.6 individuals/ha and 6.4 m2/ha of autochthonous trees with DBH ≥ 5.0 cm (Class 1); while for regeneration there were 3,864.58 individuals/ha, and 2.76 m2/ha of individuals with a height ≥ 1.30 m and DBH < 5.0 cm (Class 2). Shannon diversity (H') was 2.83 and 3.68, respectively, for Classes 1 and 2, and the corrected species richness for a 1000-individual sample (R1000) were 75.6 and 87.29 (Fisher's a index) for the same classes. The majority of the species (34.84%) was typical from the understory of wet tropical forest and had zoochoric fruit dispersal (67.57%). The results indicate that, under these conditions, a eucalyptus forest is able to provide adequate regeneration niches for native vegetation, and may represent a sink habitat for local populations.

Growth and carbon isotopes of Mediterranean trees reveal contrasting responses to increased carbon dioxide and drought

Forest dynamics will depend upon the physiological performance of individual tree species under more stressful conditions caused by climate change. In order to compare the idiosyncratic responses of Mediterranean tree species (Quercus faginea, Pinus nigra, Juniperus thurifera) coexisting in forests of central Spain, we evaluated the temporal changes in secondary growth (basal area increment; BAI) and intrinsic water-use efficiency (iWUE) during the last four decades, determined how coexisting species are responding to increases in atmospheric CO2 concentrations (Ca) and drought stress, and assessed the relationship among iWUE and growth during climatically contrasting years. All species increased their iWUE (ca. +15 to +21 %) between the 1970s and the 2000s. This increase was positively related to Ca for J. thurifera and to higher Ca and drought for Q. faginea and P. nigra. During climatically favourable years the study species either increased or maintained their growth at rising iWUE, suggesting a higher CO2 uptake. However, during unfavourable climatic years Q. faginea and especially P. nigra showed sharp declines in growth at enhanced iWUE, likely caused by a reduced stomatal conductance to save water under stressful dry conditions. In contrast, J. thurifera showed enhanced growth also during unfavourable years at increased iWUE, denoting a beneficial effect of Ca even under climatically harsh conditions. Our results reveal significant inter-specific differences in growth driven by alternative physiological responses to increasing drought stress. Thus, forest composition in the Mediterranean region might be altered due to contrasting capacities of coexisting tree species to withstand increasingly stressful conditions. © 2013 Springer-Verlag Berlin Heidelberg.

The igapó of the Negro River in central Amazonia: Linking late-successional inundation forest with fluvial geomorphology

Despite important progress on Amazonian floodplain research, the flooded forest of the Negro River igapó has been little investigated. In particular, no study has previously focused the linkage between fluvial geomorphology and the floristic variation across the course of the river. In this paper we describe and interpret relations between igapó forest, fluvial geomorphology and the spatial evolution of the igapó forest through the Holocene. Therefore, we investigate the effect of geomorphological units of the floodplain and channel patterns on tree diversity, composition and structural parameters of the late-successional igapó forest. Our results show that sites sharing almost identical flooding regime, exhibit variable tree assemblages, species richness and structural parameters such as basal area, tree density and tree heights, indicating a trend in which the geomorphologic styles seem to partially control the organization of igapó's tree communities. This can be also explained by the high variability of well-developed geomorphologic units in short distances and concentrated in small areas. In this dynamic the inputs from the species pool of tributary rivers play a crucial role, but also the depositional and erosional processes associated with the evolution of the floodplain during the Holocene may control floristic and structural components of the igapó forests. These results suggest that a comprehensive approach integrating floristic and geomorphologic methods is needed to understand the distribution of the complex vegetation patterns in complex floodplains such as the igapó of the Negro River. This combination of approaches may introduce a better comprehension of the temporal and spatial evolutionary analysis and a logic rationale to understand the vegetation distribution and variability in function of major landforms, soil distributions and hydrology. Thus, by integrating the past into macroecological analyses will sharpen our understanding of the underlying forces for contemporary floristic patterns along the inundation forests of the Negro River. © 2013 Elsevier Ltd.

Caracterização física e química do solo e avaliação do desenvolvimento de plantas de eucalipto em função do espaçamento e da adubação, visando a colheita precoce para utilização em bioenergia

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Crescimento inicial de um clone de Eucalyptus grandis em diferentes arranjos de plantio no sistema de curta rotação

Pós-graduação em Agronomia (Energia na Agricultura) - FCA

Estrutura da comunidade de trepadeiras de dois fragmentos de florestas estacional semidecidual em diferentes estágios de conservação

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Análise florística, fitossociológica e qualitativa da arborização na Praça XV de Novembro em Ribeirão Preto, SP

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

A sucessão ecológica em ambientes florestais em restauração: estrutura e dinâmica da regeneração natural

Ecological restoration aims to restore the self-sustainability potential of degraded environments. The successional trajectory of areas in restoration may differ from the reference ecosystem on a number of factors, especially the disturbance history of the area and management techniques applied in order to reverse the degradation scenario. In this sense, the objective of this study was to characterize the dynamics of natural regeneration and the structure of the regenerating community in an area of ecological restoration for 25 years on the right bank of the Rio Grande in the Power Station in Camargos that belongs to the Companhia Energetica de Minas Gerais - CEMIG, Nazareno, MG, in order to identify the current state of environmental regeneration. In November 2014, there was the first community inventory of seedlings existing in regeneration subplots (2 x 2 m) within the inclusion criteria (height ≥ 10 cm and DBH <5 cm), divided into 44 subplots (11 plots) in two areas, one area in restoration (REF) and a fragment of native vegetation (FRAG). In October 2015, the second sampling was carried out, in which individuals were resampled and recruits and dead individuals quantified. The parameters abundance, floristic similarity, density, dominance, importance value, equability, richness and diversity were analyzed in both samples. The dynamics was evaluated for the number of individuals and basal area in the period of 2014-2015 and individuals distributed according to height. The history of usage area provoked different behavior between the study environments; the patterns of the FRAG and REF communities along the years allowed the distinction between environments and demonstrated great environmental diversity, with differences in the abundance of species, floristic similarity, richness, diversity, vertical structure and dynamics parameters. In the REF area, there was a considerable increase in the density of individuals along the years and the establishment of different species. In this sense, the evaluation of natural regeneration in REF has shown that resilience is gradually being resumed, a necessary condition to support the potential for environmental self-sustainability. However, given the disturbance history, it can be concluded that the environment moves to an alternative state, which is possibly different from that prior to degradation.

Modelagem do crescimento e produção em povoamentos desbastados de Eucalyptus grandis

The aim of the study was to develop a system of growth and yield models for thinned stands of Eucalyptus spp.; and to assess the behavior of the growth in scenarios with 10% decrease or increase in rainfall. The probability distribution functions Weibull 2 and 3 parameters and Johnson SB for different methods were fitted. Correlation between the fitted parameters with age was evaluated. Dominant height growth behavior was evaluated to check if thinned stand changes its growth when compared to a non-thinned stands. The stand variables dominant height and basal area were projected and simultaneously predicted and projected, respectively. Individual tree equations were fitted, which were fitted as functions of stand level variables in order to decrease the error propagation. R software was used to fit all the proposed models and consequently all the fitted models were evaluated by their parameters significance (F-test) and graphs of predicted values in relation to the observed values around the 1:1 line. Thus, the prognosis system was made by two ways, first one using the full data set, and for the second one the dataset was restricted at age 7.5. Increase and decrease in 20% of rainfall were assessed by updating the site index function. Method of moments was the most precise to describe the diameter distribution for every age in eucalyptus stands for Johnson SB and Weibull 2 parameters pdfs. When observed for each pdf the correlation for their fitted parameters with age, we noticed that shape parameters for a thinned stand were no longer correlated with age, differently of non-thinned stands. Thus, thinning effect was accounted in the basal area prediction and projection modeling. This result emphasized the necessity of applying the Parameter Recovery method in order to assess differences and capture the right pattern for thinned and non-thinned stands in the future. Dominant height was not influenced by thinning intensity. Therefore the fitted Chapman-Richards model did not account for a stand being thinned or not. All the fitted equations behaved with good precision, no matter using full or precocious dataset. The prognosis system using full and/or precocious date set was evaluated for when using Parameter Recovery method for Sb and Weibull pdfs, and by then, graphical analysis and precision statistics showed appropriated results. Finally, the increase or decrease in rainfall regime were observed for eucalyptus stand yields and we may notice how important is to observe this effect, since the growth pattern is strictly affected by water.

Reflorestamento ciliar à margem do Reservatório da Hidrelétrica de Ilha Solteira em diferentes modelos de plantio

Pós-graduação em Agronomia - FEIS