Floristics and structure of the tree component in a Seasonal Forest remnant, Chiapetta, Rio Grande do Sul State, Brazil

In a patchy landscape, the forest remnants are important to the conservation of wild species. A phytossociological study of tree component in a remnant of Seasonal Semideciduous Forest site namely Mato do Silva (27º55’26’’ S, 53º53’15’’ W, 290 ha) was accomplished aiming to obtain data of plant community structure and its conservation status, comparing with other Seasonal Forest sites. A sample of 508 trees (DBH ≥ 5.0 cm), belonging to 31 families and 63 species, was attained through the point-quarter procedure. The outstanding families in terms of richness were Fabaceae (eleven species), Myrtaceae, Rutaceae, Sapindaceae, Lauraceae and Euphorbiaceae (four species each one). The species with the highest importance value were Cordia americana (L.) Gottschling & J.E.Mill. (35.5), Diatenopteryx sorbifolia Radlk. (32.3) and Prunus myrtifolia (L.) Urban (19.1). The dead trees presented a relative density of 4.9%. The majority of the species (65%) and individuals (55%) were zoochoric. Otherwise, the anemochory presented higher relative coverage (55%). The species with the higher IV values were mainly early secondary and anemochoric. The Shannon index of diversity (H’) was 3.68 and the Pielou’s evenness index (J’) was 0.89. These values are among the highest values observed in Seasonal Forests of South Brazil. The floristic inventory counted 117 tree species

Survival, growth and seed mass in a mixed tree species planting for Atlantic Forest restoration

Selection of tree species is a key aspect of restoration in megadiverse biomes such as the Atlantic Forest, especially in degraded areas with past intensive land use, which usually present severe limiting conditions. The species must have high survival and growth, not only in the transition between germination and seedling but also between seedling and adult plant until allowing the establishment of a self-sustaining and renewable community. In order to reach this goal, restoration initiatives carried out in the Atlantic Forest have employed high-diversity plantings of tree species from different successional guilds. Notwithstanding, long-term silvicultural knowledge is scarce for the native species from this biome, and the effectiveness of these models is controversial. Our investigation has compared the survival and growth of species and guilds in high-diversity tree species plantings in areas with previous agricultural intensive use. The species and guilds were also compared with respect to seed mass since this parameter is pointed out as an indicator of high survival in early stages. Pioneer and secondary species did not present differences in survival and seed mass, although pioneers exhibited greater growth rate. The late successional (LS) species had lower survival and growth, and higher seed mass. Survival after 8 months and between 8–15 months after seedling planting was inversely correlated with seed mass (r2 = 0.35 and r2 = 0.36, P < 0.001). On the other hand, survival after 8 months was correlated with relative growth rate (RGR) in the same periods of time (r2 = 0.34, P < 0.001). Overall average survival was 41% after 15 months, with the survival of LS species at an average of 12%. Data suggests that the inclusion of LS seedlings could impair the efficacy of restoration during early phases, at least in highly degraded areas. Equally, the inclusion of species with high seed mass should be considered with caution

Dendrometry and litterfall of neotropical pioneer and early secondary tree species

The increased forest cover loss in the tropical and subtropical regions has stimulated the development of restoration methods through tree plantations. Based on the successional model of forest development the use of different successional groups can be seen as a strategy to accelerate the re-composition of forests and an attempt to recover ecological conditions prior to disturbance. Tree species have particular growth rates and ecological needs, and this knowledge is important in the development of high diversity models of forest restoration. The objective of this study was to compare the initial growth and litterfall of native pioneer versus early secondary tree species in a mixed plantation system, and to determine the relationships between guilds and measurements. The comparison among species and guilds was made based on dendrometric and allometric parameters, and in terms of annual litterfall. The study was carried out in the Guarita Indian Area, Tenente Portela, Rio Grande do Sul, Brazil. Dendrometry of seven species was evaluated, including the pioneer tree species Mimosa scabrella Bentham, Trema micrantha (L.) Blume, Schinus molle L., Enterolobium contortisiliquum (Vell.) Morong, and the early secondary tree species Peltophorum dubium (Spreng.) Taub., Cedrela fissilis Vell. and Tabebuia alba (Cham.) Sandwith. The litterfall was quantified for the first six species. The pioneer tree species exhibited higher average height, stem diameter and crown width than the early secondary tree species. The pioneer species (except E. contortisiliquum) showed also higher values of average annual litterfall. A positive interspecific correlation between stem diameter and annual litterfall was observed. The data indicate that the choice of the species and guilds is significant to the quality of the restoration. Nevertheless, the aboveground architecture may depend on species-specific allometric characteristics and a distinction among guilds was not observed

Dendrometry and litterfall of neotropical pioneer and early secondary tree species

of neotropical pioneer and early secondary tree species. Biota Neotrop. 9(1): http://www.biotaneotropica.org. br/v9n1/en/abstract?article+bn01109012009. Abstract: The increased forest cover loss in the tropical and subtropical regions has stimulated the development of restoration methods through tree plantations. Based on the successional model of forest development the use of different successional groups can be seen as a strategy to accelerate the re-composition of forests and an attempt to recover ecological conditions prior to disturbance. Tree species have particular growth rates and ecological needs, and this knowledge is important in the development of high diversity models of forest restoration. The objective of this study was to compare the initial growth and litterfall of native pioneer versus early secondary tree species in a mixed plantation system, and to determine the relationships between guilds and measurements. The comparison among species and guilds was made based on dendrometric and allometric parameters, and in terms of annual litterfall. The study was carried out in the Guarita Indian Area, Tenente Portela, Rio Grande do Sul, Brazil. Dendrometry of seven species was evaluated, including the pioneer tree species Mimosa scabrella Bentham, Trema micrantha (L.) Blume, Schinus molle L., Enterolobium contortisiliquum (Vell.) Morong, and the early secondary tree species Peltophorum dubium (Spreng.) Taub., Cedrela fissilis Vell. and Tabebuia alba (Cham.) Sandwith. The litterfall was quantified for the first six species. The pioneer tree species exhibited higher average height, stem diameter and crown width than the early secondary tree species. The pioneer species (except E. contortisiliquum) showed also higher values of average annual litterfall. A positive interspecific correlation between stem diameter and annual litterfall was observed. The data indicate that the choice of the species and guilds is significant to the quality of the restoration. Nevertheless, the aboveground architecture may depend on species-specific allometric characteristics and a distinction among guilds was not observed. Keywords: restoration ecology, secondary succession, allometry, successional guilds. BENVENUTI-FERREIRA, G., COELHO, G.C., SCHIRMER, J. & LUCCHESE, O.A. Dendrometria e produção de serapilheira de espécies arbóreas neotropicais pioneiras e secundárias iniciais. Biota Neotrop. 9(1): http:// www.biotaneotropica.org.br/v9n1/pt/abstract?article+bn01109012009. Resumo: A perda de cobertura florestal em regiões tropicais e subtropicais tem motivado o desenvolvimento de modelos de restauração florestal através do plantio de espécies arbóreas. Tendo como base o modelo sucessional, o uso concomitante de espécies de diferentes categorias sucessionais pode ser visto como uma estratégia no sentido de acelerar o retorno a condições prévias à perturbação. As espécies arbóreas têm ritmos de crescimento e necessidades ecológicas diferentes e este conhecimento é importante para o desenvolvimento de modelos de restauração florestal com alta diversidade. O objetivo deste estudo foi comparar o crescimento inicial e a queda anual de serapilheira de espécies arbóreas nativas pioneiras e secundárias iniciais em um sistema heterogêneo de plantio, determinando a correlação entre categorias sucessionais e medidas. A comparação entre espécies e categorias foi realizada considerando parâmetros dendrométricos e alométricos, e a queda anual de serapilheira. O estudo foi conduzido na Área Indígena Guarita, Tenente Portela-RS, Brasil, para sete espécies, incluindo as pioneiras arbóreas Mimosa scabrella Bentham, Trema micrantha (L.) Blume, Schinus molle L., Enterolobium contortisiliquum (Vell.) Morong, e as secundárias iniciais Peltophorum dubium (Spreng.) Taub., Cedrela fissilis Vell. e Tabebuia alba (Cham.) Sandwith. A avaliação da produção da serapilheira foi feita nas primeiras seis espécies. As espécies pioneiras apresentaram maiores médias de altura, diâmetro do fuste e largura da copa. As pioneiras (com exceção de E. contortisiliquum) também apresentaram valores médios mais elevados de queda de serapilheira. Uma correlação interespecífica entre diâmetro do caule e produção anual de serapilheira foi observada. Os dados indicam que a escolha das espécies e guildas tem influência significativa sobre a qualidade da restauração. Entretanto, a arquitetura da parte aérea depende das características alométricas específicas das espécies e uma distinção entre guildas não foi verificada. Palavras-chave: restauração ecológica, sucessão secundária, alometria, categorias sucessionais. Benvenuti-Ferreira, G. et al

Understory structure in two successional stages of a Semi-deciduous Seasonal Forest remnant of Southern Brazil

The knowledge of structure and composition of forest strata contributes to understanding the conservation status and dynamics of plant communities. The study of forest understory is important to the knowledge of the succession process. The Seasonal Subtropical Forest remnant named Mato do Silva (27º 55'26" S and 53º 53'15" W) was studied aiming to describe the structure of understory in the late successional forest (LF) and in the young secondary forest (SF), an 11 years old post-agricultural site with canopy dominance of Ateleia glazioveana Baill. The phytosociological survey was carried out through the point quarter method and included individuals of tree and shrub species from 0.5 to 3.0 m of height. The sampling consisted of 384 individuals in LF (67 species) and 284 individuals in SF (20 species). A total of 79 species were observed, and only eight species occurred in both areas. The specific diversity (H') was 3.45 and 2.42 nats in the understory of LF and SF, respectively. The Pielou's evenness index (J) was 0.85 to LF and 0.80 to SF, respectively. Cupania vernalis Camb. and Psychotria leiocarpa Müll. Arg. were the prominent species in the LF while A. glazioveana and Solanum mauritianum Scop. were outstanding in the SF understory. Shade-tolerant and late secondary tree species occurred in large proportion in the LF forest, while pioneers and early secondary tree species predominated in the SF. In addition, certain dominant species in the understory of the SF were absent in the LF understory, such as A. glazioveana, Solanum compressum L. B. Sm. & Downs, Helietta apiculata Bentham and Gledtisia amorphoides (Griseb.) Taubert, which indicates that such species are associated to early stages of forest succession. G. amorphoides is considered an endangered species, and the early successional stages could be necessary for conservation of this species. A decrease in the pH and mineral nutrient levels in the soil was linked to the successional process, indicating the transference of nutrients to the aboveground biomass