Abstract This study aimed to determine the biometric characteristics of seeds of Tabebuia aurea and evaluate the effect of different periods of water immersion on the initial growth of seedlings. For this, the following dimensions were analyzed: length, width, and thickness of seeds with lateral wings and embryo. The moisture content, weight of a thousand seeds, and the number of seeds per kilogram were determined. The seeds were subjected to 11 treatments, as follow: control (no immersion in water; 0 hours) and periods of water immersion for 6, 12, 18, 24, 30, 36, 42, 48, 54, and 60 hours, with four replications of 25 seeds in each treatment. The aerial part and seedling root lengths were analyzed 30 days after sowing. The water content was 9.81% and the weight of a thousand seeds was 130.260 g, corresponding to about 7,677 seeds/kg. The seeds with lateral wings had mean length, width, and thickness of 5.252, 1.226, and 0.147 cm, respectively. For the embryo, these dimensions corresponded to 1.355, 0.805, and 0.103 cm. Regarding the aerial part and root length of T. aurea seedlings, immersion for 48 hours is recommended because this treatment had the best results.

Abstract This study aimed to evaluate the biometric characteristics of seeds of Jatropha mollissima (Pohl) Baill. and Cnidoscolus urens (L.) Arthur from different matrices in the semi-arid region of Brazil. For biometric evaluation, the length, width, and thickness dimensions and mass of 100 seeds of each species. The data were analysed by univariate statistics, corresponding to the position (mean, minimum and maximum values) and dispersion (standard deviation and coefficient of variation) measurements. In addition, histograms were constructed to analyse the frequency distribution pattern of biometric characteristics. J. mollissima seeds had an average length of 1.278 cm, width of 0.823 cm, thickness of 0.697 cm, and mass of 0.2220 g. The low standard error values indicated that the sampling accurately reflects the population. The frequency distribution analysis showed length between 1.240 and 1.321 cm, width between 0.787 and 0.886 cm, thickness intervals from 0.691 to 0.709 and from 0.653 to 0.671 cm, and mass of seeds concentrated between 0.1684 and 0.2477 g. For C. urens seeds, the registered biometric data were: average length of 0.789 cm, width of 0.238 cm, thickness of 0.405 cm, and mass of 0.0248 g. The sampling also accurately reflects the population as low standard error values were obtained. The frequency distribution analysis showed length between 0.768 and 0.835 cm, width between 0.234 and 0.251 cm, thickness from 0.408 and 0.423 cm, and seed mass ranging from 0.0215 to 0.0240 g. Therefore, the information provided contributes to the identification of species, and diagnosis of their genetic variability.

Abstract The correlation between biological and ecological parameters is essential for the sustainable use of species. This study aimed to assess the relationship between phenological intensity and tannin production in Sideroxylon obtusifolium (Roem. & Schult.) T.D.Penn. in environments with different precipitation regimes. The tannin production and phenological characterization were assessed through the intensity and synchrony of leaves, flower buds, flowers, and fruits in specimens from two microregions of Paraíba, northeastern Brazil. The specimens in the municipality of Sumé were not synchronous and fruiting is the least synchronous phenophase, with an index of only 0.17. The specimens in São João do Cariri had synchronization of 0.77, 0.82, and 0.92 for flower bud, flowering, and fruiting phenophases, respectively. The correlation and factorial clustering showed that fruiting has a correlation of -0.75 with the production of tannins, suggesting that low intensity of annual fruiting is necessary for higher tannin production.

Abstract This study aimed to carry out a phytosociological survey in a riparian area of an intermittent stream in the semi-arid region of Paraíba, Brazil. Fifty-one contiguous plots of 10 × 20 m (1.02 ha) were distributed along the watercourse. Living and dead shrub-tree individuals, still standing, with stem diameter at ground level (DGL) ≥ 3 cm and total height ≥ 1 m were sampled. Fifty-one species distributed in 22 families were sampled. Fabaceae, Euphorbiaceae, and Anacardiaceae had the highest species richness. Aspidosperma pyrifolium Mart. & Zucc., Combretum monetaria Mart., and Cenostigma pyramidale (Tul.) E. Gagnon & G.P. Lewis had the highest importance values. Shannon index was 2.61 nats.ind.−1 and the total basal area was 25.4 m2. Height and diameter mean values were 5.4 m and 12.4 cm, respectively. Phytosociological parameters recorded for the studied riparian vegetation have higher values in comparison with those obtained in other areas of the caatinga.

ABSTRACT Public squares are important spaces in the cities and stand out for providing improvements in the quality of urban life. Thus, this study aimed to carry out the floristic survey of public squares in the city of Areia, Paraíba state, Brazil, and analyze the similarity between their flora. The species classification was performed by consulting experts and through comparative morphology. The floristic similarity was calculated using the Jaccard index. Twenty-nine species distributed in 26 genera and 20 families were recorded. Stenotaphrum secundatum (Walter) Kuntze had the highest relative frequency (8.52%). Sixty-three percent of the species are exotic and 28% contain toxic substances. There was a significant similarity (1) only between Tenente Juvenal Espíndola and Simeão Patrício squares. The data evidence the need for better planning of floristic composition of the squares in the city of Areia, as well as for a tree planting manual.

Este trabalho teve como objetivo caracterizar aspectos relacionados com o crescimento e a bromatologia do feijão-bravo (Capparis flexuosa L.) em uma área no Curimataú, Semiárido Paraibano. Para a análise da evolução do crescimento desta espécie formou-se quatro grupos de plantas segundo a classe de altura: GI até 0,50 m; GII de 0,51 a 1 m; GIII de 1,01 a 1,50 m e GIV a >1,51 m. No período de março a dezembro de 2007 determinou-se a altura e o número de ramos dos indivíduos, sendo o diâmetro do caule registrado de março a setembro. Avaliou-se também, a composição bromatológica das folhas e talos do feijão-bravo. Em todos os grupos, o feijão-bravo apresentou crescimento lento no período chuvoso. Entretanto, até o mês de agosto, observou-se o aumento no número de ramos das plantas, independente do grupo estabelecido. No Período amostrado, não se constatou diferença (p > 0,05) entre plantas em termos de diâmetro, em todos os grupos amostrados. Os dados bromatológicos registrados foram os seguintes: matéria orgânica (91,95%); cinzas (8,05%); matéria seca (47,1%) e umidade (52,9%). Os teores de proteína bruta (8,13%); fibra bruta (32,32%); extrato etéreo (5,37%); e energia bruta (5.015 cal g-1) do feijão-bravo, dado a estas características, sugerem que esta espécie apresenta potencial para ser utilizada como forrageira.

The general aim of this study was to describe the growth and bromatology of Capparis flexuosa L. in an area of Caatinga, Paraiba State, Brazil. To analyze the growth evolution, the plants were divided in four groups according to the height classes: GI until 0.50 m; GII from 0.51 to 1 m; GIII from 1.01 to 1.50 m and GIV above >1.51 m; the plants height, the number of branches and the basal diameter were determined, in the period between March and December, 2007. The bromatological composition of leaves and branches of Capparis flexuosa was evaluated. It was showed, in all groups, that Capparis flexuosa presents a slow growth, even in the wet season. However, until August, we verified an increase in the number of branches, not dependent on the established group. During the showed period, we did not find differences (p > 0.05) between plants in terms of diameter, in all groups. The content of Crude protein (8.13%); gross fiber (32.32%); extract ether (5.37%); Organic Matter (91.95%); Ash (8.05%); dry matter (47.1%); Moisture (52.9%) and Energy (5015 cal g-1) of Capparis flexuosa sugests that this species can be used as forage.

Objetivou-se no presente trabalho contribuir para o conhecimento florístico de três áreas ribeirinhas na caatinga e realizar a comparação destas com outros estudos desenvolvidos na bacia do Rio Taperoá, semiárido paraibano. O levantamento florístico foi realizado através de coletas assistemáticas no período de janeiro/2004 a junho/2006 e abrangeu as áreas ribeirinhas presentes ao longo dos riachos intermitentes do Cazuzinha (7° 26' 13" S e 36° 54' 30" W; 564-579 m de altitude), Mares (7° 31' 53" S e 36° 33' 39" W; 536-550 m de altitude) e Farias (7° 25' 33" S e 36° 29' 21" W; 454-470 m de altitude). O levantamento das três áreas registrou um total de 91 espécies, das quais 68 ocorreram na área do riacho do Cazuzinha, 62 no riacho dos Mares e 56 no riacho do Farias. As famílias com maior número de espécies e de gêneros foram Fabaceae, Euphorbiaceae e Rubiaceae. Do total de espécies registrado para as três áreas, 15 estão presentes nas listas relacionadas para matas ciliares de outros estados do Brasil, 26 são endêmicas da Caatinga e 10 foram exclusivas. Analisando a similaridade florística entre as áreas estudadas e outros cinco levantamentos, observou-se que a maior identidade florística está relacionada principalmente com a distância geográfica e às características de uso e ocupação da terra.

Aimed in the present work to study the floristic composition of shrubby and tree in three riparian vegetation areas and compare with other study realized in the basin of the Taperoá River, in the paraiban semiarid. A floristic survey was carried out from January 2004 throughout June 2006, covering riparian areas along the intermittent streams Cazuzinha (7° 26' 13" S and 36° 54' 30" W; 564-579 m of altitude), Mares (7° 31' 53" S and 36° 33' 39" W; 536-550 m of altitude), and Farias (7° 25' 33" S and 36° 29' 21" W; 454-470 m of altitude). The floristic survey carried out in all three areas, generated a total of 91 species, of which, 68 were collected along Cazuzinha stream, 62 along Mares stream, and 56 along Farias stream. The families with the largest number of species and genera identified were: Fabaceae, Euphorbiaceae and Rubiaceae. Of the total of species registered for the three areas, 15 are present in the known lists of riverine bushes in other states of Brazil, 26 are endemic of the Caatinga (Brazilian northeastern savanna) and 10 of them had been exclusive of the researched area. The analysis of floristic similarity of the riparian areas of the present study in a comparison with other five surveys performed formerly showed that the highest floristic identity is related mainly to geographical distance and to the soil use and land occupancy.

Considerando o papel relevante e o nível de degradação presente nas áreas ciliares, a pesquisa objetivou estudar a composição florística do componente arbustivo-arbóreo da vegetação ciliar em diferentes ambientes hídricos do semi-árido paraibano na bacia do rio Taperoá. O levantamento florístico foi realizado no período de junho/2002 a fevereiro/2003 e abrangeu nove pontos distribuídos ao longo de rios, riachos, lagoa e açude. A definição das atividades apoiou-se em análise de cartas e mapas da vegetação em escala de 1:100.000 e caminhadas aleatórias que permitiram a realização de coleta de material vegetal, utilizado para identificação por meio de consultas a especialistas e de morfologia comparada, usando bibliografia especializada e análise das exsicatas depositadas no herbário Lauro Pires Xavier - JPB (UFPB, João Pessoa, PB). A vegetação arbustivo-arbórea da mata ciliar nos nove pontos amostrados foi representada por 43 espécies, das quais 41 são pertencentes a 19 famílias, e duas espécies permaneceram indeterminadas. As famílias que apresentaram o maior número de espécies foram Mimosaceae (sete), Caesalpiniaceae (cinco) e Euphorbiaceae (cinco). Os resultados da análise de agrupamento indicaram que as áreas ciliares apresentaram certa particularização em termos de composição florística, o que se refletiu nos baixos índices de similaridades entre o conjunto de áreas amostradas.

Considering the relevant role and the current level of degradation of riparian areas, this work aimed to study the floristic composition of shrub-tree riparian vegetation at different hydric environments in the Taperoá river basin, in the semi-arid region of the Paraíba State, Northeast Brazil. The survey was performed from June 2002 to February 2003. Nine sampling sites were distributed along rivers and streams, and around lagoon, and dam. The definition of activities was based on the analysis of charts and vegetation maps drawn to the scale 1:100,000 and through walks carried out at random for collecting plant material. The plants were identified by comparing their morphology to the collection housed at the Herbarium Lauro Pires Xavier (Universidade Federal da Paraíba, João Pessoa, PB), and by consultation to the specialized bibliography and to botanical experts. The shrub-tree riparian vegetation from the nine sampling sites was represented by 43 plant species, from which 41 belong to 19 families and two species were not determined. The families with the largest number of species were: Mimosaceae (seven), Caesalpiniaceae (five), and Euphorbiaceae (five). The cluster analysis showed that the riparian areas had a particular distinguishing feature with respect to floristic composition, as indicated by the low similarity index estimated among the sampled areas.