Phytosociology of the woody component in vegetacional refuge, Buíque, PernambucoPhytosociology of the woody component of a vegetacion refuge in the municipality of Buíque, Pernambuco. Physiognomy and structure of a evergreen shrub vegetation found on the windward slope of the Catimbau range, at the Cigano property, Buíque (8°67 ' LS and 37°1 ' LW, altitude 800 m) were determined, as a contribution to the knowledge of the vegetation on sedimentary plateaus of Pernambuco. The point centered quarter method was used with 100 points distributed in 10 parallel lines, each point 10 m and each line 30 m apart. All living and standing dead individuals with stem diameter ⊕ 3 cm at soil level and plant height ⊕ 1 m were sampled. Total density, total basal area, average and largest diameter and height were 2.208 ind./ha, 6.07 m 2 /ha, 5.1 cm and 22.0 cm and 2.3 m and 7 m, respectively, revealing a shrub pattern different from those of the caatinga and carrasco studied in Northeastern Brasil. Of the 35 sampled species, Eremanthus capitatus, Piptadenia obliqua, Gochnatia oligocephala, Senna cana var. cana and Eugenia punicifolia were reponsible for 63.3% of the importance value index total. Shannon diversity index for species was 2.73 nats/ind.Key words: phytosociology, vegetational refuge, semi-arid. RESUMOCom o objetivo de contribuir para o conhecimento da vegetação lenhosa das chapadas sedimentares do sertão de Pernambuco, foi realizada a caracterização fisionômica e a análise da estrutura da vegetação arbustiva perenifólia localizada em uma vertente a barlavento da serra do Catimbau, na propriedade sítio Cigano, Buíque (8°67 ' LS e 37°1 ' LW) a 800 m de altitude. Em cem pontos quadrantes, distribuídos em 10 linhas paralelas, interdistantes 30 m, cada uma com 10 pontos quadrantes distanciados 10 m, foram amostrados todos os indivíduos com diâmetro do caule ⊕ 3 cm no nível do solo e altura total ⊕ 1 m. Densidade total, área basal total, alturas e diâmetros médios e máximos foram de 2.207,7 ind./ha, 6,07 m 2 /ha, 2,3 m e 7,0 m, 5,1 cm e 21,96 cm, respectivamente, revelando um padrão fisionômico distinto das vegetações de caatinga e carrasco estudadas no nordeste do Brasil. Das 35 espécies amostradas, Eremanthus capitatus, Piptadenia obliqua, Gochnatia oligocephala, Senna cana var. cana e Eugenia punicifolia foram responsáveis por 63,3% do índice do valor de importância total. O índice de diversidade de Shannon para espécies foi de 2,73 nats/ind. Palavras-chave: fitossociologia, refúgio vegetacional, semi-árido.

-(Diversity and infectivity potential of arbuscular mycorrhizal fungi in an area of "caatinga" in the Xingó Region, State of Alagoas, Brazil). The region occupies 2800 km 2 , in the States of Pernambuco, Alagoas, Sergipe and Bahia, and constitutes a preserved part of the Northeastern semi-arid ecosystem. Evaluation of the diversity and density of propagules of arbuscular mycorrhizal fungi (AMF) in the soil, as well as of the mycorrhizal colonization in plants of the area was carried out by sampling of soil and roots during the dry (August/2000) and rainy (March/2001) seasons, in two subareas (Piranhas and Olho d'Água do Casado) in Alagoas. More than 95% of the plants, among the 71 examined, formed arbuscular mycorrhiza (5-80% colonization). Among these 30 phanerogamic species, belonging to 14 families, only Pilosocereus sp. was not colonized. The average percentages of colonization (≅ 16-20%) were similar in both sampling periods. There was an inverse relationship between number of spores and the most probable number (MPN) of infective propagules in the area of Olho d'Água, with lower density of spores (< 2 spores.g -1 of soil) and higher MPN of propagules (4.7 and 11.6 spores.g -1 of soil), in the rainy and dry periods. Number of spores and MPN of propagules were similar in the Piranhas area during the rainy season; in the dry season the number of spores was 1.5 times higher than the MPN. Twenty-four taxa of AMF, mostly of Acaulosporaceae and Glomaceae, were identified. The AMF are well represented, forming mycorrhizal association with most "caatinga" plants, despite the severe climatic limitations of the region.

RESUMO -(Flora de um Brejo de Altitude na escarpa oriental do planalto da Borborema, PE, Brasil). Os estudos nas florestas montanas nordestinas (brejos de altitude) indicam que as ombrófilas apresentam elevada riqueza de espécies e são mais relacionadas com a floresta ombrófila de terras baixas. Considerando o desconhecimento sobre as florestas ombrófilas sub-montanas, foi realizado o levantamento do Brejo de Bonito, Pernambuco, com o objetivo de conhecer seu perfil florístico. São apresentadas informações sobre o coletor/número, hábito e padrão de distribuição de cada espécie. Os resultados foram comparados a 22 levantamentos da Floresta Atlântica (latu sensu) nordestina. No brejo de Bonito foram coletadas 217 espécies, distribuídas em 65 famílias. Dessas, cerca de 50% são citados em outras florestas montanas de Pernambuco e de terras baixas de Pernambuco e da Bahia. A maior parte das espécies encontradas tem distribuição na América do Sul, ocorrendo desde a porção norte, penetrando na costa leste brasileira e também na porção central do Brasil e, às vezes, no domínio do semi-árido, nos Brejos de Altitude. Outra porção representativa distribui-se desde a América Central até a porção centronorte da América do Sul, com poucas ocorrendo também na parte sul da América do Norte (Estados Unidos e México).Palavras-chave : floresta ombrófila sub-montana, nordeste do Brasil, brejo de altitude, padrão de distribuição ABSTRACT -(Floristics of an upland forest in the oriental slope of the Borborema plateau, Pernambuco State, Brazil). Studies in the northeastern upland forests (brejo de altitude) indicate that the humid ones show higher richness of species and have more floristic simalarity with the lowland humid forests. Considering the lack of data about humid sub-montane forests, a survey was carried out in the upland forest of Bonito, Pernambuco, aiming to identify their floristic composition. Voucher, habit, and pattern of distribution of each species are presented. The results were compared with 22 surveys in the northeastern Atlantic Rainforest (latu sensu). Two hundred and seventeen species, distributed in 65 families, were sampled at the study area. Among those, 50% were cited in other upland forests and lowland forests in Pernambuco and Bahia States. The majority of species are scattered along South America, occurring from the north portion, penetrating through the Atlantic coast, as well as in the Brazilian central plateau, and sometimes reaching the semi-arid regions within the upland forests. Another important group of species are distributed starting at Central America to the middle region of South America, with a few occurring also in the south of North America (United States and Mexico).

RESUMO -(Phyllanthus L. (Phyllanthaceae) em Pernambuco, Brasil). O estudo foi baseado na análise morfológica de materiais herborizados e observação em campo. Foram registradas 17 espécies diferenciadas, principalmente, através do número e forma das sépalas, número e união dos estames, além do sexo da inflorescência e ornamentação da testa das sementes. Dessas espécies, seis (P.

Caatinga Ethnobotany: Anthropogenic Landscape Modification and Useful Species in Brazil's Semi-Arid Northeast This study explores the contribution of anthropogenic landscapes in providing useful botanical resources to a Caatinga community in Pernambuco, Brazil. Ethnobotanical data were collected through semi-structured interviews using the checklistinterview method and by means of a "field herbarium" of the most abundant species in the anthropogenic zones. We recorded 119 species distributed in 36 families, of which 79 were found to be useful. Forage was the most prominent use category, containing 84% of the citations, followed by medicinals (36.70%), foods (10.12%), and wood (8.86%). Herbaceous species predominated (63.29%), followed by shrubs (3.79%), sub-shrubs (21.51%), trees (8.86%), and creepers (2.53%). Trees exhibited a greater number of uses than other life-forms (p<0.05). Significant differences in richness were found, with the highest richness of species (χ2=60.28, p<0.05), genera (χ2=49.03, p<0.05), and families (χ2=20.16, p<0.05) appearing in the rainy season. We concluded that fodder use was the most important category in our anthropogenic research areas, accounting for a higher number of species, genera, and families. The next most important categories were medicinal, timber, and food plants, respectively.