Perseu da Silva Aparício

Controle da matocompetição em plantios de dois clones de Eucalyptus × urograndis no Amapá

This study aimed to analyze the initial growth of two clones of the hybrid Eucalyptus urograndis in different weed management systems, during the year of implantation, in the Amapa area. The study was developed in Amapa Florestal Celulose S.A. (AMCEL), from September/2006 until November/2007, with two experimental areas located in Itaubal, AP (0°42’N; 50°450°48’W). Two clones of the hybrid Eucalyptus urograndis (H3911 and H3243) were planted by mechanized form, with one clone per stand. The areas were cleaned using an application of glyphosate. A repeated measure model was used. Treatments consisted of the two clones and six silvicultural treatments with four replicates (T1: without cleaning; T2: total cleaning; T3: cleaning in two bands of 50cm at the plantation line; T4: cleaning in two bands of 75cm at the plantation line; T5: cleaning in two bands of 100cm at the plantation line; and T6: circle cleaning with 75cm of ray). In the beginning of the evaluation, only plants height were measured. From the fifth month on, the diameter, at 1.30m (DBH), was also measured. The Mauchly sphericity test was carried out and hypotheses of nullity were tested for interactions time x clone and time x clone x types of cleanness. Differences among means were compared by Tukey test (p < 0.05). For clone H3911, the treatment T5 and Total Cleaning showed statistically similar heights, which did not occur with the other treatments. For the DBH of clone H3911 plants, growth was similar, though with different rates of growth during the evaluation period, where T1 and T6 showed greater sensitivity to competition. The heights of clone H3243 plants remained statistically similar at the end of the experiment, however, for DAP, it was observed that plants from T1 were more sensitive to the presence and effect of weeds, athough they had a mean DBH statistically superior to other treatments in the first month of evaluation.The growth of plants from the Total Cleaning treatment was superior in comparison to the other treatments over a year of assessment for both clones tested.

Níveis de regeneração natural em floresta de terra firme no Amapá Brasil

This study aimed to identify natural regeneration in dense ombrophilous phytophysiognomy of the State Forest of Amapa, describing relations between vertical stratums. The study area is located in Porto Grande/AP, eastern Amazon. Three conglomerates were implanted, equidistant at 2.500 m, for natural regeneration estimative. We used 100 plots of 10 x 10 m for study of saplings (5.0 < DBH (diameter at 1.30 m soil) < 10.0 cm) and sticks (5 x 5 m) (2.5 < DBH <5.0 cm) in each conclomerate. We collected the heights and popular names. The heights were divided into three classes of regeneration to estimate phytosociological parameters of frequency and density, as well as regeneration by size class and overall. Diversity was estimated by Shannon Index. Floristic similarity between sticks and saplings was also analyzed. The inventory included 2,700 individuals belonging to 38 botanical families, 93 genera and 141 species of trees, with 6 undetermined. The Shannon index was 4.21 (saplings) and 4.11 nats.ind.-1 (sticks). It has been found the occurrence of 33 common species in three classes of regeneration. The total natural regeneration varied from 10.3 to 0.1% (sticks) and 5.6 to 0.1% (saplings). The species with the lowest percentages were Indeterminate, Vouacapoua americana, Carapa guianensis, Virola calophylla and Manilkara huberi. Thus, it is evident that species are developing their successional process efficiently, ensuring conservation of phytophysiognomy in the region.

Modelagem da estrutura diamétrica de Epurea falcata Aubl em floresta de várzea, Macapá-AP

O presente trabalho teve como objetivo analisar a estrutura diametrica de Epurea falcata Aubl . em Floresta de varzea localizada nas margens do Igarape da Fortaleza, municipio de Macapa–AP. Foram alocadas 30 parcela, sendo 10 de 10m x 15m, 10 de 10m x 30m e 10 de 10m x 50m, lancadas de forma inteiramente casualizada nas margens do curso d’agua. Foram mensurado todos os individuos com diâmetro a 1,30 m do solo (DAP) ≥ 5 cm e o numero de classes diametricas foi definido pela formula de Stuges. Para a especie estudada, foram ajustadas e testadas as funcoes de densidade e probabilidade de Weibull 3P, Normal, Log normal, Meyer, Gama e Beta e para a validacao se utilizou o teste de Kolmogorov-Smirnov (p=5%). Dos 46 individuos amostrados, foram geradas 7 classes diametricas com amplitude de 9 cm. A especie apresentou uma distribuicao que tende ao “J” invertido, onde grande quantidade de individuos estao nas classes de menor diâmetro. A funcao de Meyer foi a que melhor se ajustou para representacao da distribuicao diametrica da especie. Conclui-se que a comunidade em questao nao esta senescente, com maior abundância de individuos jovens do que adultos.

Modelagem da distribuição diamétrica da Carapa guianensis Aubl. Em floresta de várzea Macapá-AP, Brasil

A exploracao dos recursos naturais sem o conhecimento cientifico e uma realidade global. Estudos que visem estimar o potencial produtivo das florestas sao fundamentais para nortear o desenvolvimento de modelos de producao, bem como inferir sobre sua estrutura atual por meio de variaveis mensuraveis. O presente trabalho objetivou ajustar e testar funcoes de densidade probabilisticas visando selecionar modelos para representar a distribuicao diametrica para a especie Carapa guianensis Aublet (Andiroba). O estudo foi realizado em area de varzea no municipio de Macapa-AP. Foram amostrados os individuos com diâmetro a 1,30 m do solo (DAP) ≥ 10 cm, em 20 unidades amostrais com dimensoes de 10 x 15 m, alocadas de forma inteiramente casualizada. As funcoes testadas foram Weibull 3 parâmetros, Normal, Log normal, Gamma, Meyer e Beta. Aplicou-se o teste de Kolmogorov-Smirnov a um nivel de 5% de probabilidade. Na analise dos resultados todos os modelos apresentaram uma boa aderencia, porem o modelo Weibull 3P apresentou o melhor ajuste (D cal = 0,021; D tabelar =0,212). Portanto a funcao Weibull 3P e a que melhor descreve a distribuicao diametrica das Andirobeiras na area de estudo.