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A síndrome de dispersão de sementes está relacionada à migração das espécies e colonização de novos locais adequados para sobrevivência e reprodução. Foram estudados três estágios sucessionais de mata ciliar no domínio da Mata Atlântica (capoeira = cinco anos de regeneração; secundária = 45 anos de regeneração; e floresta madura = sem intervenção há 35 anos). As espécies foram classificadas nas síndromes de zoocoria, anemocoria e autocoria. A zoocoria predominou nos três estágios da sucessão da mata ciliar, com percentuais variáveis de 82% até 93% das espécies e 47% até 92% dos indivíduos. A segunda síndrome de dispersão mais comum foi a anemocoria, prevalecendo com elevada abundância relativa na capoeira (25% dos indivíduos). A autocoria ocorreu no sub-bosque da floresta madura com indivíduos da espécie Gymnanthes concolor. Aparticipação da zoocoria nos três estágios da sucessão demonstra que a relação planta-animal tem elevada importância para a sucessão florestal em ambiente ciliar na região do extremo sul da Mata Atlântica.

Neste estudo, utilizaram-se dados de uma vegetação de caatinga na Estação Florestal de Experimentação (EFLEX) do IBAMA, em Açu-RN. Os parâmetros estruturais analisados foram: densidade,frequência, dominância, distribuição diamétrica, posição sociológica e regeneração natural. Procuraram-se, através da interpretação das estimativas dos parâmetros fitossociológicos e da estrutura diamétrica, informações básicas para o manejo florestal e a definição de uma metodologia para o plano de. manejo preliminar da Estação Experimental estudada. O presente trabalho verificou que a catingueira (Caesalpinia pyramidalis Tul.) é a espécie mais característica da floresta; que a floresta apresentou, em média, 853 árvores/ha e 9,831 O m2 /ha de área basal para as árvores com DAP igualou superior a 5 cm; e que a maioria das espécies mostrou posição sociológica irregular e regeneração escassa. Algumas recomendações foram feitas no sentido de se conhecer a dinâmica dessa floresta, dar continuidade aos estudos estruturais nesta mesma vegetação e estudar sobre as causas da escassa regeneração das espécies valiosas.

ABSTRACT The objective of this study was to evaluate the structure (horizontal and vertical) of a Deciduous Forest, located between the municipalities of Piratuba and Ipira (SC). 14.000 m2 of tree communities were analyzed, sub- divided into 14 plots of 10 x 100 m, where all individuals with DBH equal to or greater than 4.0 cm were sampled and identified. For natural regeneration were sampled 560 m2, divided into 14 plots of 10 x 4 m. In the tree strata were sampled 2.125 individuals belonging to 34 families, 80 genera and 113 species with a total density of 1.517 ind.ha-1. Natural regeneration were sampled 196 individuals belonging to 24 families and 49 species with a total density of 3.500 ind. ha-1. Luehea divaricata Mart., Actinostemon concolor (Spreng) Müll. Arg. and Parapiptadenia rigida (Benth.) Brenan had of value of increased importance (7,1%, 7,0 % and 5,3%, respectively). Actinostemon concolor got high value Relative Natural Regeneration (18,1%). The low percentage of natural regeneration of species as Luehea divaricata and Parapiptadenia rigida, respectively 3,7% and 1,5%, typical of EDF , may represent a maintenance commitment in the community. The study revealed the presence of exotic species with invasive potential, as Hovenia dulcis Thumb. These facts point to the importance of the adoption of management measures, since the forest fragment studied is advancing successional terms, however, anthropogenic interference with signals in the floristic composition. These facts point to the importance of the adoption of management measures, since the forest fragment studied is suffering anthropogenic impact, influencing the ecological succession mechanisms.

ABSTRACT A problem of global dimensions, the occupation of areas by invasive alien species is studied in this paper focusing on the increasing presence of Pinus sp in the Lagoa do Peixe National Park, at Rio Grande do Sul State, Brazil. From satellite imagery and the use of remote sensing and geoprocessing techniques, this paper presents a space-time mapping of the presence of this invasive alien species in the northern area of the Park, from 1985 to the 2017. Planted and disseminated areas of Pinus were mapped through visual analysis and pixel classification by the Spectral Angle Mapper (SAM) method, using images from the Landsat and Rapid Eye satellites. The results showed a constant growth rate in the areas of Pinus, with acceleration at the end of the analyzed period, confirming the invasive capacity of Pinus sp and the dispersion of their seeds by the wind. The excellent performance of the SAM algorithm in the identification of Pinus areas was demonstrated, as well as the importance of the use of satellite images in the analysis of the question.

ABSTRACT This study aimed at inventorying the natural regeneration of tree species in an Alluvial Araucaria Forest in the "Planalto Sul Catarinense" region, SC, Brazil; evaluating the dissimilarity between its adult and regenerative components; and verifying the natural regeneration floristic sharing among its different fragments. The regenerative component has been sampled and identified within 48 plots and classified according to the following height classes: Class 1, plants with height varying from 15 cm up to 1 m; Class 2, plants with height varying from 1 and 3 m; and Class 3, plants with height higher than 3 m and DBH (diameter at breast height) smaller than 5 cm. The floristic composition of adult individuals in the area and of regenerative individuals from other fragments has been obtained from the database of the Laboratory of Dendrology of CAV/UDESC. The structure of the regeneration was evaluated by phytosociological descriptors. Dissimilarity between the adult and the regenerative components has been determined by Jaccard, Sorensen and Bray-Curtis distances. The regeneration floristic sharing analysis of different areas was conducted by a dendrogram. A total of 818 individuals belonging to 59 species have been sampled, being Allophylus edulis (A.St.-Hil. et al.) Hieron. ex Niederl. the species with the greatest relative importance. Elevated similarity between the regenerative and adult components have been observed (from 0.24 to 0.43), suggesting a low floristic-structural turnover between components. The area under study have shown a greater floristic connection (