Papers by Vagner Santiago Vale
Journal of Tropical Biology, 2013
"Local changes caused by dams can have drastic conse-quences for ecosystems, not only because the... more "Local changes caused by dams can have drastic conse-quences for ecosystems, not only because they change the water regime but also the modification on lakeshore areas. Thus, this work aimed to determ'ine the changes in soil moisture after damming, to understand the con-sequences of this modification on the arboreal community of dry forests, some of the most endangered systems on the planet. We studied these changes in soil moisture and the arboreal community in three dry forests in the Araguari River Basin, after two dams construction in 2005 and 2006, and the potential effects on these forests. For this, plots of 20m x10m were distributed close to the impoundment margin and perpendicular to the dam margin in two deciduous dry forests and one semi-deciduous dry forest located in Southeastern Brazil, totaling 3.6ha sampled. Besides, soil analysis were undertaken before and after impoundment at three different depths
(0-10, 20-30 and 40-50cm). A tree (minimum DBH of 4.77cm) community inventory was made before (T0) and at two (T2) and four (T4) years after damming. Annual dynamic rates of all communities were calculated, and statistical tests were used to determine changes in soil moisture and tree communities. The analyses confirmed soil moisture increases in all forests, especially during the dry season and at sites closer to the reservoir; besides, an increase in basal area due to the fast growth of many trees was observed. The highest turnover occurred
in the first two years after impoundment, mainly due to the higher tree mortality especially of those closer to the dam margin. All forests showed reductions in dynamic rates for subsequent years (T2-T4), indicating that these forests tended to stabilize after a strong initial impact. The modifications were more extensive in the
deciduous forests, probably because the dry period resulted more rigorous in these forests when compared to semideciduous forest. The new shorelines created by damming increased soil moisture in the dry season, mak-ing plant growth easier. We concluded that several changes occurred in the T0-T2 period and at 0-30m to the
impoundment, mainly for the deciduous forests, where this community turned into a “riparian-deciduous forest” with large basal area in these patches. However, unlike other transitory disturbances, damming is a permanent alteration and transforms the landscape to a different scenario, probably with major long-term consequences for the environment."
This study was carried out in a semideciduous forest in southeastern Brazil. Five ecological attr... more This study was carried out in a semideciduous forest in southeastern Brazil. Five ecological attributes were used to define the functional groups: dominant stratum of the species, light demand of the plant, seed dispersal, likely pollinator, and deciduousness. The groups were formed through a species matrix and its attributes, and they were delimited according to the Jaccard similarity coefficient and a dendrogram generated by the group average (UPGMA). The analysis used was satisfactory, indicating the formation of four coherent groups with distinct functions both with regard to the community and the ecosystem. The results indicate a tree community in a late successional stage, with relations between flora and fauna species.
This study investigates the effects of reservoir flooding in the moreimportant regenerative plant... more This study investigates the effects of reservoir flooding in the moreimportant regenerative plants population distributed in deciduous season forests impacted by Hydropower. Samples were
collected from the plant population before and after the flood and calculated specie’s mortality and recruitment rates. To evaluate the moisture content variation in soil samples were collected before and after the flood. The increased of the moisturehad effects on the population structure of woody species in the regenerative community, acting negatively or positively about mortality and recruitment rates, depending on specie. Species not tolerant to increase water availability need a special attention, because it implies the management plan and rehabilitation of impacted sites by artificial reservoir.
We examined floristic patterns of ten seasonal semideciduous forest sites in southeastern Brazil ... more We examined floristic patterns of ten seasonal semideciduous forest sites in southeastern Brazil and conducted a central sampling of one hectare for each site, where we took samples and identified all individual living trees with DBH (diameter at breast height, 1.30 m)≥ 4.8 cm. Arboreal flora totaled 242 species, 163 genera, and 58 families. Fabaceae (38 species) and Myrtaceae (20 species) were families with the largest number of species. Only Copaife ra lang s dorffii and Hy me naea courbar iloccurred at all sites. Multivariate analysis (detrended correspondence analy sis and cluster analysis) using two-way indicator species analysis (TWINSPAN) indicated the formation of a group containing seven fragments in which Sipar una guiane nsis was the indicator species. This analysis revealed that similarities between studied fragments were due mainly to the successional stage of the community.
Foi realizado o levantamento fitossociológico de umfragmento de floresta estacional semidecidual ... more Foi realizado o levantamento fitossociológico de umfragmento de floresta estacional semidecidual localizado na reserva legal da FazendaSão Pedro-Itaú. O estudo analisou um hectare do fragmento utilizando 25 parcelas permanentes de 20 x 20 m, onde todos os indivíduos vivos arbóreos com circunferência a altura do peito maior que 15 cm foram foram classificadas quanto aos grupos sucessionais e síndromes de dispersão. Foram amostrados 1144 indivíduos distribuídos em 103 espécies e 41 famílias. O valor de equabilidade e do índice de diversidade de Shannon foram 0,83 e 3,87, respectivamente. Neste fragmento 17% são espécies pioneiras, 49% secundárias iniciais e 34% secundárias tardias, demonstrando um estágio intermediário de sucessão. Ocorre alta porcentagem de espécies zoocóricas (67%), podendo indicar alta atividade da fauna dispersora.O sub-bosque com alta porcentagem de espécies zoocóricas e baixo número de pioneiras também reforçam um estádio
intermediário, progredindo a um estádio de mais avançado, na sucessão florestal.
Seasonal semideciduous forests (FES) assemblage possesses high heterogeneity and diverses factors... more Seasonal semideciduous forests (FES) assemblage possesses high heterogeneity and diverses factors contributing to floristic and structural variation of these forests. Thus, it was carried throught the study of floristic composition and horizontal and vertical structures in a community of a tree FES. The area is located at coordinates 18°29’28”S and 48°23’45”W. One hectare of area was delimited and was sampled trees with a circunference 1.30 m ≥ 15 cm and estimated the height of individuals. The phytossociological parameters (relatives density, dominance and frequency) had been calculated. The plots were categorized as the percentage of total gaps and species classified on the vertical stratum. The analysis enabled the classification of species into successional groups. There was sampled 839 individuals with predominance of understory late secondary species, with little presence of pioneers. Based on the analysis of the forest of Fazenda da Mata can be classified as a primary stage of conservation
O presente estudo apresenta o monitoramento para quatro comunidades arbóreas sob impacto recente ... more O presente estudo apresenta o monitoramento para quatro comunidades arbóreas sob impacto recente de represamento: a floresta ciliar localizada no Trecho de Vazão Reduzida, e três florestas estacionais que passaram a ficar próximas ao lago artificial gerado por barragens. Como foco, temos a avaliação destas comunidades ao longo de quatro anos após a construção da barragem, bem como analisar mudanças no nível de espécies. Por fim, buscamos relacionar as alterações ocorridas por meio das análises de grupos de espécies com semelhantes repostas a estes distúrbios e, com isso, buscar indicar o destino destas florestas e as reais conseqüências das modificações ocorridas. Temos como hipótese central de que as mudanças na umidade do solo, mesmo em um curto espaço de tempo para árvores (quatro anos), causaram drásticas modificações na estrutura e diversidade destas florestas, sendo esperadas altas taxas de dinâmica, sobretudo devido ao desfavorecimento de espécies especialistas (especialistas a saturação hídrica, no caso da floresta ciliar sujeita a uma condição de vazão do rio reduzida, e especialistas de ambientes com déficit hídrico, no caso das florestas estacionais) e favorecimento de espécies generalistas quanto a disponibilidade hídrica.
"The present study aimed to determine the floristic, structural and ecological between ... more "The present study aimed to determine the floristic, structural and ecological between physiognomies in a Cerrado remnant, Monte Carmelo, MG. From the phytossociological survey, we assessed the ecological patterns related to the species dispersion guilds and deciduousness. The floristic similarity between the physiognomies was parsed using quantitative and qualitative data (presence/absence) through the Jaccard similarity coefficient and Morisita-Horn indice. The urban remnant presented four vegetable physiognomies, classified in semideciduous seasonal forest, stricto sense cerrado, cerradão and gallery forest. We sampled 153 species, distributed in 49 families. The semideciduous forest covers the largest portion of the Park and has the greatest diversity of species. The gallery forest presented the less diversity, having as main representatives species adapted to conditions of hydromorphic soil. The predominance of zoochoric species in four physiognomies confirms the importance of biological agents on gene flow of these formations. The highest percentage of species anemochoric was found in the stricto sense cerrado and cerradão. The floristic similarity between the physiognomies present in urban remnant is low, demonstrating that small
environmental variations reflect major floristic changes. Each physiognomies has its peculiarities, not only in relation to physical conditions, but also in relation to fundamental ecological processes, such as biological diversity and interaction with the fauna disperser, which may explain the great beta diversity found in the Cerrado biome."
Este estudo tem como objetivo a análise de grupos funcionais de um fragmento de floresta estacion... more Este estudo tem como objetivo a análise de grupos funcionais de um fragmento de floresta estacional semidecidual urbano na cidade de Uberlândia-MG e qual a importância desses grupos ao longo do ano. Foi utilizado um hectare com amostras de todos os indivíduos com CAP ≥ 15 cm. As características utilizadas para a formação dos grupos funcionais foram: 1) síndrome de dispersão, 2) síndrome de polinização e 3) tolerância a dessecação de sementes. Foi elaborado uma matriz de presença/ausência pelo qual foi realizado o coeficiente de similaridade de Jaccard entre as espécies. A partir desses coeficientes, construiu-se um dendrograma utilizando-se a média de grupo (UPGMA). Sete grupos funcionais foram encontrados, quatro ornitocóricos, dois mastocóricos e apenas um grupo anemocórico. A maior diversificação de polinizadores foi visualizada nos grupos zoocóricos, demonstrando a importância da fauna para a diversificação funcional da flora. O grupo anemocórico apresentou como polinizador único as abelhas e foi tipicamente ortodoxo, cujas sementes perduram no ambiente podendo formar um banco de sementes. Sementes recalcitrantes foram encontradas em dois grupos, devido a estas sementes serem provenientes de frutos carnosos. Este trabalho demonstra a importância e o potencial de recursos deste fragmento urbano e sua capacidade de sustentar a fauna local.
Historical review of studies in seasonal semideciduous forests in Brazil: a perspective for conse... more Historical review of studies in seasonal semideciduous forests in Brazil: a perspective for conservation - Biodiversity conservation is one of the biggest challenges faced this century, due to the high level of human disturbance in natural ecosystems. The seasonal semideciduous forests (SSF) have suffered the same degradation process as other Brazilian ecosystems. Given this context, this study aimed to review the literature regarding the classification, characterization and distribution of SSF in Brazil, and to present a historical review of previous studies. In the early 1980s and, for a period of 15 years, floristics and hytosociological studies dominated scientific research, basically describing and comparing different forest remnants. From mid-1990, new studies were developed using other approaches. These studies not only initiated new lines of research, but also gradually increased the emphasis on floristic analysis, with the outcome of establishing new hypotheses and more defined links of cause and effect between the structural aspects of vegetation and environmental factors, both functional and phytogeographical.
Studies on seasonal semideciduous forests (FES) are required in order to characterize the structu... more Studies on seasonal semideciduous forests (FES) are required in order to characterize the structure and verify the formation of patterns, also comparing the floristic composition among fragments. A remnant of FES, in Uberada, MG, was assessed by surveying twenty-five plots (20 × 20 m each) totalizing one hectare. All living trees with circumference at breast height (1.30 m above the ground) > 15 cm were recorded. Common phytosociological parameters and floristic similarity with other FES remnants were calculated. A total of 805 individuals were surveyed, representing 90 species. Micrandra elata (Euphorbiaceae) was the most important species in the community, followed by Galipea jasminiflora (Rutaceae). Besides the low relative density of pioneer species, the high basal area (45.8 m2 ha-1) and the peculiar flora are evidences of a mature and well preserved forest. The similarity analysis resulted in four distinct groups, related to geographical regions, and apparently, floristic similarity is higher among well preserved forests.
Seasonal semideciduous forests present high biodiversity and are currently threatened by the proc... more Seasonal semideciduous forests present high biodiversity and are currently threatened by the process of fragmentation. This paper describes the phytosociological structure of woody species in a fragment of seasonal semideciduous forest in the municipality of Ipiaçu, MG, and classify the species by their dispersal syndromes and successional groups. Twenty five plots of 20x20 were allocated, and 837 individuals were sampled representing 50 species distributed in 25 families. Fabaceae was the most representative family with 15 species. Hymenaea courbaril was the species with highest VI (18%), followed by Piptadenia gonoacantha (10.7%) and Luehea grandiflora (10.6%). Of the listed species 58% are pioneers, 21% first secondary and 21% late secondary; of these, 58% are zoochoric, 33% anemochoric and 17% autochoric. The fragment has an acid soil with a high content of Fe and Mn, base saturation below 50%. The low species richness (50 spp.) and small basal area (15,15 m2.ha-1), the high density of pioneers and opportunistic species and the presenceof several gaps formed by human activity over time, mainly selective cutting of valuable timber trees are all strong signs of the disturbance within the study area.
The deciduous forests are among the most endangered forests in the tropics. The deciduous forests... more The deciduous forests are among the most endangered forests in the tropics. The deciduous forests under direct influence areas of large hydropower areas are subject to the environmental changes caused by the reservoir. This study investigates the effects of reservoir flooding on the population of plants with at least 1 meter above soil height of two typical species widely distributed in deciduous forests: M. urundeuva Allemão and A. colubrina (Vell.) Brenan. Samples were collected from the population before and after the floods (2006 and 2009) for both species in two forests under the influence of the Amador Aguiar I Hydropower artificial reservoir. To evaluate the moisture content variation in the soil, samples were collected before and after the floods (2005 and 2008). M. urundeuva had a high mortality, whereas A. colubrina shows more tolerance to the new conditions. The soil moisture presented an increase in amplitude of the mean variation between years and seasons, especially in the dry season. Both species present similar ecological and functional characteristics, the negative effect of increased moisture in M. urundeuva doesn’t cause system functional loss, considering that A. colubrina can supply the ecological functions of similar species.
Considering that the regimes of burning modify important factors of the structure and composition... more Considering that the regimes of burning modify important factors of the structure and composition of the species of a plant community, the objective of this work was to analyze the effect of burning on the floristic composition and structure of the wood vegetation of the cerrado sensu stricto at the Parque Estadual da Serra de Caldas Novas (PESCAN), Goiás, submitted to different times of burning. Two areas had been used of Cerrado sensu stricto: one was submitted to burning in 2002 and 2006 and the other area did not suffer burning in the same period. For each area, 25 parcels of 20x20 m were established and all the wood flora (C30≥15 cm) was included in the study. Both areas studied presented similar floristic composition, evidenced by the Sorensen Coefficient, which found 84% of similarity in the floristic composition between the areas. However, the vegetation structure presented relevant differences, evidenced by the Similarity´s Index of Bray Curtis, which found a value of 0,67. This value was reflected by changes in the studied communities’ structure. The burnt area presented a smaller number of individuals and species, a smaller value for the basal area and, therefore, the Shannon Diversity Index (H’) and Evenness (J’). Therefore, the frequency and intensity of the burnings in the area had not been enough to evidence their effects on the process of alteration in the composition of the wood species. However, the fire exerted a relevant role in the modification of the vegetation structure.
The need to know more about diversity and species distribu -tion patterns of the cerrado biome ha... more The need to know more about diversity and species distribu -tion patterns of the cerrado biome has increased, due to its ac -celerated destruction. Hence, a floristic and phytosociological inventory was conducted in a cerrado (stricto sensu) area, lo -cated in the Parque Estadual da Serra de Caldas Novas, state of Goiás, Brazil, comparing the quantitative and qualitative results with those from other 15 areas. Fifty plots of 20×20m (2ha) were established and all trees with CSH 30 >15cm were included in the study. A total of 70 species, 51 genera and 31 families were found at the site. Fabaceae was the richest fam -ily (with 13 species), followed by Vochysiaceae (7). The high -est importance values were for Tabebuia aurea Benth. & Hook, Kielmeyera coriacea Mart. & Zucc and Qualea parviflora Mart. The floristic comparative analysis showed that geographic dis -tance was the most important parameter, followed by other en -vironmental factors. The quantitative structural patterns reflect variations in more reduced scale, probably under strong influ -ence of environmental variations.
The combination of some species ecological characteristics for the creation of ecological groups ... more The combination of some species ecological characteristics for the creation of ecological groups has helped to identify the broader significance and validity of the patterns currently known for different vegetation types. From the analysis of phytosociological and diameter structure of tree species in a semideciduous forest fragment, this study aimed to classify the species in ecological groups and assess the conservation status of this remnant and possible disruptions in the structure of some populations. We sampled all trees with CBH > 15 cm, present in 25 plots (20x20 m). Species were classified by successional groups and dispersal syndrome. We recorded 976 individuals in 86 species belonging to 38 families. The sample had a composition of 42 early secondary species (48.8%), 27 late secondary (31.4%), 16 pioneer (18.6%) and one unclassified (1.2%). The group formed by early secondary showed higher density and relative frequency, while the group formed by the late secondary species stands out with higher values of relative dominance. Regarding the dispersal syndrome, 60 species presented zoochoric dispersal, 21 anemochoric and five autochorich. Diametric distribution analysis for the successional groups suggested problems in regeneration for the pioneer group. These results suggest that the studied forest is in an intermediate stage of successional development, moving toward a late stage, mainly due to the presence and dominance of some late successional species as to the low density of pioneer species.
"The growing fragmentation of natural habitats intensifies
the necessity to evaluate biological... more "The growing fragmentation of natural habitats intensifies
the necessity to evaluate biological diversity contained in plant remnants. From the survey of species composition and structure of the tree component in a remnant of semideciduous
seasonal forest, this study aimed to classify the species in ecological groups that provide subsidies to gauge the level of conservation of this fragment. Were used 25 plots of 20 x
20 m totaling 1 ha, being included in the sample all living individuals with CAP ≥ 15 cm. The species were classified according to the successional group, dispersion syndrome and
deciduousness. Were sampled 1063 individuals belonging to 88 species and 40 families. The value of diversity and equability (3.53 and 0.79, respectively) and the high basal area sampled (34.68 m 2.ha-1) reflect the high species richness and indicate that the fragment, although small (22.3 ha), can be considered as an ecosystem conserved. The large
number of species with zoochoric dispersion, which increase the availability of resources for the local fauna, and abundance of species early secondary and late secondary, as indicative of the maturity of the vegetation, underline the importance of conserving the fragment, and reaffirm the potential of this remnant as an important habitat and natural corridor for species of the region. "
The phytosociological survey was realized in a semideciduous forest fragment located i... more The phytosociological survey was realized in a semideciduous forest fragment located in the legal reserve of Irara Farm, Uberlândia - MG. This study analyzed one hectare of the fragment using 25 adjacent and systematic plots of 20 x 20 m, where all the alive tree individuals with perimeter at breast height higher than 15 cm were included and identified. The species were classified as successional groups and dispersal syndromes. Were sampled 945 individuals in 73 species, 65 genres and 36 families. The value of equability and Shannon’s diversity were 0,81 and 3,47, respectively. In this fragment 17% were pioneer species, 49% early secondary species and 34% late secondary species, demonstrating an intermediary succession stage. Occur high percentage of zoochoric species (77%), that can indicate high activity of disperser fauna.
The presence of fire in the Cerrado is an important molder factor of the population structure of ... more The presence of fire in the Cerrado is an important molder factor of the population structure of this biome. The aim of this work was to evaluate differences in the impact of frequent forest fires in the population and in the sprout (producing new shoots) of four Cerrado plant species, Kielmeyera coriacea, Kielmeyera grandiflora,Tabebuia aurea and Ouratea hexasperma, in two areas that suffered different frequencies of fire in the last 15 years in the Parque Estadual da Serra de Caldas Novas (GO). It was demarked, in each area, 50 plots of 5 x 10m, totaling 2,500 m
2 in each sample area. In these transects the heights of all individuals belonging to the four species was quantified and measured. The sprouts were classified as its types
(aerial or underground). Each population had its structure analyzed by comparing the height of plants among the areas with the “U” test of Mann-Whitney. In the area I 243
individuals were sampled and 308 individuals in the area II. All species presented a large number of aerial sprouts by l.5m tall. However the species presented different behavior as the height necessary to produce aerial sprouts. A large number of
underground sprouts were verified in all species. The population presents alteration on structure due the loose of the aerial part by successive forest fires. So, the burning events modify the structure and the composition of populations of all species since
they respond in different ways to fire.
"In this work, we utilize the assessment of functional groups (FG) and functional div... more "In this work, we utilize the assessment of functional groups (FG) and functional diversity (FD) to evaluate and compare the ecological functions of two types of dry forest of South Eastern Brazil. Hence, we hypothesized that forests with different species richness could have similar FD and FG, but distinct ecological functions. The floristic composition from two physiognomies (deciduous and semideciduous forests) of six tree communities was carried out in the state of Minas Gerais, South-Eastern Brazil. The inventory was pooled together considering the traits of species such as: shade tolerance, deciduousness and desiccation tolerance of seeds; one structural feature: position on vertical strata; and two animal-plant interactions: dispersal syndrome and pollination syndrome. We chose two multivariate analyses to infer to the functional groups and used the one-way ANOVA to test differences between the abundance of the groups in the two physiognomies. The difference in FD between the two physiognomies was tested using the Shannon diversity index and the Hutcheson t-test. Both physiognomies had the same FG and FD. The most abundant group in the semi-deciduous
forest was G1, which occupied lower communities (shade tolerant and perennial), whereas G4 for deciduous forest was anemochoric and autochoric of superior community strata that is light demanding. The functional diversity between the two physiognomies showed that semi-deciduous contains more species than the deciduous ones (75% more species) and are more diverse with the Shannon index of 3.3. Hence, the number of species alone had little importance when we analysed functions in ecosystems. The more abundant groups in each forest had completely different traits and were complementary in their functions to the ecosystem. In this case, a species-rich and less-species-rich system provided different key functions to the ecosystem despite their differences in species richness, diversity or physiognomic type. The use of species-rich and less-species-rich areas would present different key groups, and as such, this may be the best alternative to choose priority areas for conservation."
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Papers by Vagner Santiago Vale
(0-10, 20-30 and 40-50cm). A tree (minimum DBH of 4.77cm) community inventory was made before (T0) and at two (T2) and four (T4) years after damming. Annual dynamic rates of all communities were calculated, and statistical tests were used to determine changes in soil moisture and tree communities. The analyses confirmed soil moisture increases in all forests, especially during the dry season and at sites closer to the reservoir; besides, an increase in basal area due to the fast growth of many trees was observed. The highest turnover occurred
in the first two years after impoundment, mainly due to the higher tree mortality especially of those closer to the dam margin. All forests showed reductions in dynamic rates for subsequent years (T2-T4), indicating that these forests tended to stabilize after a strong initial impact. The modifications were more extensive in the
deciduous forests, probably because the dry period resulted more rigorous in these forests when compared to semideciduous forest. The new shorelines created by damming increased soil moisture in the dry season, mak-ing plant growth easier. We concluded that several changes occurred in the T0-T2 period and at 0-30m to the
impoundment, mainly for the deciduous forests, where this community turned into a “riparian-deciduous forest” with large basal area in these patches. However, unlike other transitory disturbances, damming is a permanent alteration and transforms the landscape to a different scenario, probably with major long-term consequences for the environment."
collected from the plant population before and after the flood and calculated specie’s mortality and recruitment rates. To evaluate the moisture content variation in soil samples were collected before and after the flood. The increased of the moisturehad effects on the population structure of woody species in the regenerative community, acting negatively or positively about mortality and recruitment rates, depending on specie. Species not tolerant to increase water availability need a special attention, because it implies the management plan and rehabilitation of impacted sites by artificial reservoir.
intermediário, progredindo a um estádio de mais avançado, na sucessão florestal.
environmental variations reflect major floristic changes. Each physiognomies has its peculiarities, not only in relation to physical conditions, but also in relation to fundamental ecological processes, such as biological diversity and interaction with the fauna disperser, which may explain the great beta diversity found in the Cerrado biome."
the necessity to evaluate biological diversity contained in plant remnants. From the survey of species composition and structure of the tree component in a remnant of semideciduous
seasonal forest, this study aimed to classify the species in ecological groups that provide subsidies to gauge the level of conservation of this fragment. Were used 25 plots of 20 x
20 m totaling 1 ha, being included in the sample all living individuals with CAP ≥ 15 cm. The species were classified according to the successional group, dispersion syndrome and
deciduousness. Were sampled 1063 individuals belonging to 88 species and 40 families. The value of diversity and equability (3.53 and 0.79, respectively) and the high basal area sampled (34.68 m 2.ha-1) reflect the high species richness and indicate that the fragment, although small (22.3 ha), can be considered as an ecosystem conserved. The large
number of species with zoochoric dispersion, which increase the availability of resources for the local fauna, and abundance of species early secondary and late secondary, as indicative of the maturity of the vegetation, underline the importance of conserving the fragment, and reaffirm the potential of this remnant as an important habitat and natural corridor for species of the region. "
2 in each sample area. In these transects the heights of all individuals belonging to the four species was quantified and measured. The sprouts were classified as its types
(aerial or underground). Each population had its structure analyzed by comparing the height of plants among the areas with the “U” test of Mann-Whitney. In the area I 243
individuals were sampled and 308 individuals in the area II. All species presented a large number of aerial sprouts by l.5m tall. However the species presented different behavior as the height necessary to produce aerial sprouts. A large number of
underground sprouts were verified in all species. The population presents alteration on structure due the loose of the aerial part by successive forest fires. So, the burning events modify the structure and the composition of populations of all species since
they respond in different ways to fire.
forest was G1, which occupied lower communities (shade tolerant and perennial), whereas G4 for deciduous forest was anemochoric and autochoric of superior community strata that is light demanding. The functional diversity between the two physiognomies showed that semi-deciduous contains more species than the deciduous ones (75% more species) and are more diverse with the Shannon index of 3.3. Hence, the number of species alone had little importance when we analysed functions in ecosystems. The more abundant groups in each forest had completely different traits and were complementary in their functions to the ecosystem. In this case, a species-rich and less-species-rich system provided different key functions to the ecosystem despite their differences in species richness, diversity or physiognomic type. The use of species-rich and less-species-rich areas would present different key groups, and as such, this may be the best alternative to choose priority areas for conservation."
(0-10, 20-30 and 40-50cm). A tree (minimum DBH of 4.77cm) community inventory was made before (T0) and at two (T2) and four (T4) years after damming. Annual dynamic rates of all communities were calculated, and statistical tests were used to determine changes in soil moisture and tree communities. The analyses confirmed soil moisture increases in all forests, especially during the dry season and at sites closer to the reservoir; besides, an increase in basal area due to the fast growth of many trees was observed. The highest turnover occurred
in the first two years after impoundment, mainly due to the higher tree mortality especially of those closer to the dam margin. All forests showed reductions in dynamic rates for subsequent years (T2-T4), indicating that these forests tended to stabilize after a strong initial impact. The modifications were more extensive in the
deciduous forests, probably because the dry period resulted more rigorous in these forests when compared to semideciduous forest. The new shorelines created by damming increased soil moisture in the dry season, mak-ing plant growth easier. We concluded that several changes occurred in the T0-T2 period and at 0-30m to the
impoundment, mainly for the deciduous forests, where this community turned into a “riparian-deciduous forest” with large basal area in these patches. However, unlike other transitory disturbances, damming is a permanent alteration and transforms the landscape to a different scenario, probably with major long-term consequences for the environment."
collected from the plant population before and after the flood and calculated specie’s mortality and recruitment rates. To evaluate the moisture content variation in soil samples were collected before and after the flood. The increased of the moisturehad effects on the population structure of woody species in the regenerative community, acting negatively or positively about mortality and recruitment rates, depending on specie. Species not tolerant to increase water availability need a special attention, because it implies the management plan and rehabilitation of impacted sites by artificial reservoir.
intermediário, progredindo a um estádio de mais avançado, na sucessão florestal.
environmental variations reflect major floristic changes. Each physiognomies has its peculiarities, not only in relation to physical conditions, but also in relation to fundamental ecological processes, such as biological diversity and interaction with the fauna disperser, which may explain the great beta diversity found in the Cerrado biome."
the necessity to evaluate biological diversity contained in plant remnants. From the survey of species composition and structure of the tree component in a remnant of semideciduous
seasonal forest, this study aimed to classify the species in ecological groups that provide subsidies to gauge the level of conservation of this fragment. Were used 25 plots of 20 x
20 m totaling 1 ha, being included in the sample all living individuals with CAP ≥ 15 cm. The species were classified according to the successional group, dispersion syndrome and
deciduousness. Were sampled 1063 individuals belonging to 88 species and 40 families. The value of diversity and equability (3.53 and 0.79, respectively) and the high basal area sampled (34.68 m 2.ha-1) reflect the high species richness and indicate that the fragment, although small (22.3 ha), can be considered as an ecosystem conserved. The large
number of species with zoochoric dispersion, which increase the availability of resources for the local fauna, and abundance of species early secondary and late secondary, as indicative of the maturity of the vegetation, underline the importance of conserving the fragment, and reaffirm the potential of this remnant as an important habitat and natural corridor for species of the region. "
2 in each sample area. In these transects the heights of all individuals belonging to the four species was quantified and measured. The sprouts were classified as its types
(aerial or underground). Each population had its structure analyzed by comparing the height of plants among the areas with the “U” test of Mann-Whitney. In the area I 243
individuals were sampled and 308 individuals in the area II. All species presented a large number of aerial sprouts by l.5m tall. However the species presented different behavior as the height necessary to produce aerial sprouts. A large number of
underground sprouts were verified in all species. The population presents alteration on structure due the loose of the aerial part by successive forest fires. So, the burning events modify the structure and the composition of populations of all species since
they respond in different ways to fire.
forest was G1, which occupied lower communities (shade tolerant and perennial), whereas G4 for deciduous forest was anemochoric and autochoric of superior community strata that is light demanding. The functional diversity between the two physiognomies showed that semi-deciduous contains more species than the deciduous ones (75% more species) and are more diverse with the Shannon index of 3.3. Hence, the number of species alone had little importance when we analysed functions in ecosystems. The more abundant groups in each forest had completely different traits and were complementary in their functions to the ecosystem. In this case, a species-rich and less-species-rich system provided different key functions to the ecosystem despite their differences in species richness, diversity or physiognomic type. The use of species-rich and less-species-rich areas would present different key groups, and as such, this may be the best alternative to choose priority areas for conservation."