INFLUENCE OF SOILS AND TOPOGRAPHIC GRADIENTS ON TREE SPECIES DISTRIBUTION IN A BRAZILIAN ATLANTIC TROPICAL (original) (raw)

Influence of Soil and Topography on the Composition of a Tree Community in a Central Brazilian Valley Forest

Edinburgh Journal of Botany, 2005

The purpose of the present study was to investigate the correlations between environmental variables related to the substrate (soil and topography) and the distribution of tree species in a valley forest in the Chapada dos Guimarães National Park, Mato Grosso State, Brazil. The forest lies in the Cerrado Domain of Central Brazil where the dominant vegetation cover is cerrado (woody savanna). A survey of the tree community registered all live individuals with circumference at breast height (cbh)≥15cm found in eighteen 600m2 plots (total area 1.08ha). The substrate variables used in the gradient analyses were obtained from a topographic survey and from analyses of the chemical and physical properties of soil samples. A principal components analysis of soil and topography variables and a canonical correspondence analysis of the species–environment relationships produced similar results, separating both the substrate variables and the tree species abundances, mainly according to the two...

Effects of soils and topography on the distribution of tree species in a tropical riverine forest in south-eastern Brazil

Journal of Tropical Ecology, 1994

ABSTRACTThe relationships between soil properties, topography and tree species distribution were analysed in a tropical riverine forest at the margins of the Rio Grande, in Bom Sucesso, state of Minas Gerais, south-eastern Brazil. The forest was sampled by three 0.18 ha plots, with each plot made up of eight contiguous 15 m X 15 m quadrats, four of which were placed at the river margin and the remaining four in the forest interior. A canonical correspondence analysis indicated that the species' density distribution was significantly correlated with some soil chemical characteristics and topographical features. The soils of the three sample plots showed statistically significant differences for the levels of Ca, Mg, K and pH, with the fertility (expressed by the cation exchange capacity) increasing from Plot I to Plot III. These variations were mainly explained by the first canonical axis while the second was strongly correlated with topographical variables, separating the quadra...

Soil profile, relief features and their relation to structure and distribution of Brazilian Atlantic rain forest trees

Scientia Agricola, 2012

In tropical forests, the environmental heterogeneity can provide niche partitioning at local scales and determine the diversity and plant species distribution. Thus, this study aimed to investigate the variations of tree species structure and distribution in response to relief and soil profile features in a portion of the largest remnant of Brazilian Atlantic rain forest. All trees ≥ 5 cm diameter at breast height were recorded in two 0.99 ha plots. Topographic survey and a soil characterization were accomplished in both plots. Topsoil samples (0-20 cm) were taken from 88 quadrats and analyzed for chemical and particle size properties. Differences for both diversity and tree density were identified among three kinds of soils. A canonical correspondence analysis (CCA) indicated that the specific abundance varied among the three kinds of soils mapped: a shallow Udept-Orthent / Aquent gradient, probably due to differences in soil drainage. Nutrient content was less likely to affect tree species composition and distribution than relief, pH, Al 3+ , and soil texture. Some species were randomly distributed and did not show restriction to relief and soil properties. However, preferences in niche occupation detected in this study, derived from the catenary environments found, rise up as an important explanation for the high tree species diversity in tropical forests.

Influence of soil fertility on the distribution of tree species in a deciduous forest in the Triângulo Mineiro region of Brazil

Plant Ecology, 2007

Dry semideciduous and deciduous forests occur only on calcium-rich soils and occupy almost 20% of the 200 million ha of the cerrado region of central Brazil. Other savanna physiognomies of woodlands and grasslands, and gallery forests generally occur on acid soils with low calcium levels. The literature on phytosociological aspects of such cerrado physiognomies is quite abundant whereas there is very little information on deciduous forests. Also lacking is information on soil fertility and its influence on species distribution. The objective of the present study was to study the distribution of native species within a dry deciduous forest in the Araguari river valley, Uberlâ ndia, Minas Gerais as related to soil properties. A 1-ha sampling area, with no apparent difference in physiognomy, was divided Joã o Paulo De Souza is a scholarship holder of CNPq.

Structure of the tree stratum of three swamp forest communities in southern Brazil under different soil conditions

Restinga forests are commonly known to be plant communities rather poor in tree species. This study aimed to describe and explain the association between the floristic-structural similarities and the environmental conditions in three Swamp Restinga Forest communities in southern Brazil. In 13 plots of 100 m 2 each, we sampled all individual trees (circumference at breast height >12 cm and height ≥3 m). We collected soil samples in each plot for chemical and textural analyses. Phytosociological parameters were calculated and different structural variables were compared between areas. The density of individuals did not differ between areas; however, the maximum height and abundance of species differed between the site with Histosols and the other two sites with Gleysols. Further, a canonical correspondence analysis based on a matrix of vegetation and that of environmental characteristics explained 31.5% of the total variation. The high floristic and environmental heterogeneity indicate that swamp-forests can shelter many species with low frequency. Most species were generalists that were not exclusive to this type of forest. Overall, our study showed that swamp-forests within the same region can show considerable differences in composition and structure and can include species-rich communities, mostly due to the presence of species with a broader distribution in the Atlantic Rainforest domain on sites with less stressful environmental conditions and without waterlogged conditions.

Relationships between tree component structure, topography and soils of a riverside forest, Rio Botucaraí, Southern Brazil

Plant Ecology, 2007

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 Botucaraí watershed near the confluence with the Rio Jacuí, 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 hye...

Heterogeneity of a Tree Species Community in an Alluvial Area of Santa Catarina, Brazil

Floresta e Ambiente

The aim of the present study was to characterize the floristic-structural heterogeneity of the tree species in an alluvial forest remnant considering three sectors: forest-river edge, forest interior and forest/non-forest matrix edge. Forty-eight plots of 200 m 2 were allocated and all tree individuals with a diameter at breast height (dbh) equal to or greater than 5 cm were measured and identified. Data was analyzed by Shannon's diversity index, Pielou evenness and phytosociological descriptors. Plots were ordered through NMDS. Sixty-six species were sampled and Myrtaceae was found to be the richest family. Diversity and evenness reached 2.96 and 0.71, respectively. Sebastiania commersoniana (Baill.) L.B.Sm. & Downs presented the highest importance value (21.22%). The NMDS showed that tree components are spatially partitioned according to sectors, therefore indicating floristic-structural heterogeneity.

Structural and Floristic Variations in an Atlantic Subtropical Rainforest in Southern Brazil

Floresta e Ambiente, 2018

The Atlantic Subtropical Rainforest covers a huge area of Santa Catarina state, starting on the coast and going through the Serra Geral. Along its distribution, the vegetation changes according to altitude, geomorphology, and soil. In the attempt to evaluate vegetation variations related to different soil types in an Atlantic Forest remnant, 43 plots of 200 m 2 were sampled. All the individuals with DBH ≥ 5.0 cm were measured. We have found consistent floristic and structural variations, which separated sample plots with Litholic Neosol and Rogosol situated in slopes from those with Yellow-Red Ultisol and Haplic Cambisol, as well as plots with Fluvic Neosol from Haplic Gleisol in plateaus. Species richness increased according to water availability and soil depth, with the plateaus' soils being the richest. Each area was characterized by a range of indicator species and the results indicated that soil attributes are important drivers of vegetation variation.

Brazilian Decidual Tropical Forest enclaves: floristic, structural and environmental variations

Brazilian Journal of Botany, 2017

Several theories have been proposed to explain the raised richness and diversity of species in native tropical forests, with an emphasis on those that invoke the niche characteristics. In the present study, we sample the woody vegetation in four enclaves of Deciduous Forests and investigate whether environmental variables can explain the floristic and structural differences among the sampled fragments. The studied areas are located the ''Cerrado'' biome core zone and in ''Cerrado''-Atlantic Forest and ''Cerrado-Caatinga'' transition zones. The woody vegetation (diameter at breast height-DBH C 5 cm) was sampled in 100 plots of 20 9 20 m, 25 plots in each enclaves. The investigated environmental variables were chemical and textural properties of the soil, rockiness, declivity and altitude. We found significant differences for the floristic variables (richness, diversity), among all the environmental variables, as well as for the density, height and for the DBH first class. We noticed strong influence of the environmental variables, and the nutrients availability, texture, soil acidity and the land relief are the most responsible for the floristic-cultural difference. We propose that the gradient existence of rainfall has influenced the edaphic characteristics, creating variations in the habitats, which may have favored the arrival and establishment of different species in each study area and the distinctive development of the woody vegetation at the enclaves to the Deciduous Forest.