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ABSTRACT We sought to evaluate the floristic and structural variations between three areas with distinct backgrounds in the Sooretama Biological Reserve, remnantd of Lowland Atlantic Forest in Brazil. For vegetation sampling, 30 transects were established in three different areas: post-pasture (PAS), post-fire (FIR), and preserved (PRE) remnants, totaling a sample area of 0.3ha. All individuals in the woody layer with diameter at breast height ≥ 2.5cm were sampled. Variations in floristic composition were evaluated by means of NMDS, based on the presence or absence of species. There are clear variations between the three areas evaluated, in which the PRE area presents greater species richness, floristic diversity, and basal area, with parameters similar to forests of high diversity in northern Espírito Santo and southern Bahia. The performance of inventories and monitoring of the remnants of Lowland Atlantic Forests in neglected regions are fundamental for planning conservation and enrichment measures of these vegetations

The study was conducted on four islands located west of Bejaia (north-eastern Algeria) to collect baseline information about diversity and composition of insects. Data were collected during summer and spring of 2015 using traps, sweep nets and the Japanese umbrella sampling methods. A total of 1691 individuals belonging to 112 species were collected. Totals of 72, 56, 41 and 34 species were recorded in Pisans Island, El Euch Island, Sahel Islet and Ail Islet, respectively. Of the 1,691 individuals recorded, 39.85 %, 30.51 %, 18.03 % and 11.59 % were recorded in Pisans Island, El Euch Island, Sahel Islet and Ail Islet, respectively. Shannon-Weaver index ranged from 2.96 to 3.34 and Equitability between 0.77 and 0.87. The composition of the insect community differed between sampled islands (NMDS, Stress =. 0.013). Eleven (11) insect species composed over 50 % of dissimilarity between islands. Two species (Cassida viridis (L.) and Pheidole pallidula (Nyl.) accounted for more than 5 % of the diversity on all islands. Sorensen's similarity coefficient showed that Pisans and El Euch islands have the highest similarity (45.37 %), while the lowest similarity was recorded between Pisans Island and Sahel Islet (15.53 %).

ABSTRACT Studies on the natural regeneration of tree species communities are important for providing information on forest development capacity. This research aimed to evaluate the floristic-structural variations of the tree regenerative component along a topographic gradient in an ecotonal area between a Mixed Ombrophilous Forest and a Deciduous Seasonal Forest of Santa Catarina, Brazil. 30 sampling units of which all regenerating tree species individuals have been identified were allocated in the forest fragment. The sampling units were then distributed along a topographic gradient into lower, intermediate and upper sectors. Abundance, richness, Shannon's diversity index (H') and Pielou's evenness index (J) have been determined for both the whole community as for each sector. The community floristic-structural organization was verified by the means of the non-metric multidimensional scaling (NMDS), the indicator species analysis and the permutational multivariate analysis of variance (PERMANOVA). Abundance differences among sectors were analyzed through the Kruskal-Wallis test with post hoc multiple nonparametric test while richness differences were verified through rarefaction. Regenerating individuals density in the upper sector [129 (21.300 ind.ha-1)] was lower than both in the lower [401 (63.800 ind.ha-1)] and intermediary [241 (36.300 ind.ha-1)] sectors. There was variation in the floristic-structural composition (p < 0.001) among topographic positions; the lower sector was the most distinct one and showed the highest number of indicator species.

Este estudo teve como objetivos avaliar a similaridade florística do componente arbóreo de 39 remanescentes de florestas superomontanas no domínio atlântico, Brasil, e analisar a influência de variáveis geográficas e climáticas sobre os padrões observados. Foi utilizada uma matriz binária de presença e ausência das espécies arbóreas compiladas dos 39 levantamentos florísticos e fitossociológicos. Para conhecer a relação da composição florística das áreas com variáveis ambientais e espaciais, foram extraídas as coordenadas geográficas e os dados climáticos de cada área. Com o objetivo de avaliar a similaridade florística dos remanescentes, foi utilizado um dendrograma e, para determinar a influência de variáveis ambientais e espaciais sobre os padrões florísticos, foi utilizada a análise multivariada NMDS. O dendrograma e a NMDS demonstraram a formação de agrupamentos, predominantemente entre remanescentes localizados em uma mesma unidade fitogeográfica. Observou-se a existência de um gradiente ambiental ligado às condições climáticas. Em áreas com maiores valores de sazonalidade térmica, amplitude térmica anual, precipitação, latitude e longitude, ocorreram florestas superomontanas com matriz ombrófila e, em áreas com maiores valores de temperatura média, amplitude térmica diária, isotermalidade, sazonalidade da precipitação e temperatura mínima no mês mais frio, ocorreram predominantemente florestas com matriz estacional.

Este estudo teve como objetivos avaliar a similaridade florística do componente arbóreo de 39 remanescentes de florestas superomontanas no domínio atlântico, Brasil, e analisar a influência de variáveis geográficas e climáticas sobre os padrões observados. Foi utilizada uma matriz binária de presença e ausência das espécies arbóreas compiladas dos 39 levantamentos florísticos e fitossociológicos. Para conhecer a relação da composição florística das áreas com variáveis ambientais e espaciais, foram extraídas as coordenadas geográficas e os dados climáticos de cada área. Com o objetivo de avaliar a similaridade florística dos remanescentes, foi utilizado um dendrograma e, para determinar a influência de variáveis ambientais e espaciais sobre os padrões florísticos, foi utilizada a análise multivariada NMDS. O dendrograma e a NMDS demonstraram a formação de agrupamentos, predominantemente entre remanescentes localizados em uma mesma unidade fitogeográfica. Observou-se a existência de um gradiente ambiental ligado às condições climáticas. Em áreas com maiores valores de sazonalidade térmica, amplitude térmica anual, precipitação, latitude e longitude, ocorreram florestas superomontanas com matriz ombrófila e, em áreas com maiores valores de temperatura média, amplitude térmica diária, isotermalidade, sazonalidade da precipitação e temperatura mínima no mês mais frio, ocorreram predominantemente florestas com matriz estacional.

Multivariate techniques have become a useful tool for studying the phenotypic diversity of Germplasm Bank accessions, since they make it possible to combine a variety of different information from these accessions. This study aimed to characterize the phenotypic dispersion of garlic (Allium sativum L.) using two multivariate techniques with different objective functions. Twenty accessions were morphologically characterized for bulb diameter, length, and weight; number of cloves per bulb; number of leaves per plant; and leaf area. Techniques based on generalized quadratic distance of Mahalanobis, UPGMA (Unweighted Pair Group Method with Arithmetic Mean) clustering, and nMDS (nonmetrric MultiDimensional Scaling) were applied and the relative importance of variables quantified. The two multivariate techniques were capable of identifying cultivars with different characteristics, mainly regarding their classification in subgroups of common garlic or noble garlic, according to the number of cloves per bulb. The representation of the phenotypic distance of cultivars by multidimensional scaling was slightly more effective than that with UPGMA clustering.

Multivariate techniques have become a useful tool for studying the phenotypic diversity of Germplasm Bank accessions, since they make it possible to combine a variety of different information from these accessions. This study aimed to characterize the phenotypic dispersion of garlic (Allium sativum L.) using two multivariate techniques with different objective functions. Twenty accessions were morphologically characterized for bulb diameter, length, and weight; number of cloves per bulb; number of leaves per plant; and leaf area. Techniques based on generalized quadratic distance of Mahalanobis, UPGMA (Unweighted Pair Group Method with Arithmetic Mean) clustering, and nMDS (nonmetrric MultiDimensional Scaling) were applied and the relative importance of variables quantified. The two multivariate techniques were capable of identifying cultivars with different characteristics, mainly regarding their classification in subgroups of common garlic or noble garlic, according to the number of cloves per bulb. The representation of the phenotypic distance of cultivars by multidimensional scaling was slightly more effective than that with UPGMA clustering.

Se evaluó la diversidad de árboles contenida en 96 parcelas circulares de 0.1 ha, distribuidas en un intervalo altitudinal entre 441 y 1,740 m en la Depresión Central de Chiapas. Las parcelas se clasificaron mediante un análisis de agrupamiento jerárquico y se ordenaron a lo largo de un gradiente ambiental por medio de un análisis de escalamiento multidimensional no métrico (NMDS). La clasificación permitió reconocer cinco asociaciones vegetales, tres de ellas correspondientes al bosque tropical caducifolio (BTC) y dos a los bosques de Quercus. La riqueza regional está representada por un total de 233 especies, en 152 géneros y 57 familias botánicas. La contribución de las parcelas a la diversidad total fue mayor en las asociaciones del bosque tropical caducifolio que en las de Quercus. La composición de especies estuvo dominada por individuos de etapas sucesionales tardías en las asociaciones del BTC (40-56%), en tanto que en los bosques de Quercus la mayor contribución fue de especies secundarias (46-54%). La ordenación (NMDS) mostró una relación significativa de las parcelas con 10 de 12 variables climáticas, de las cuales el promedio anual de la temperatura media del mes más caliente (r2 = 0.74, P