Giant Araucaria trees in Brazilian Atlantic forests today are rare but remain critically important for structuring these ecosystems, providing unique and rare habitat elements that can serve as points of reference for their management. Old-growth Araucaria trees, with their complex crowns and big trunk cavities, supply more important ecological services than smaller trees with simple crowns. Forest ecology managers lack information on the old-growth structures of Brazilian Araucaria forest, their ecological importance and their potential societal values and uses. In this study, we investigated old-growth attributes of Araucaria angustifolia and relate their wide structural variability to ecological management goals. In this study, we used currently available data on the last large old Araucaria trees, as well as our own new records, from large trees of 1.6-3.2 m diameter in the Araucaria forests in southern Brazil. In order to quantify the structural attributes of these remnant trees, their main trunks, any reiterated canopy trunks and trunk cavities were measured for diameters, heights and volumes. These old-growth trees had an average height of 38.4 m, and total tree volumes ranged from 21.5 to 106.6 m 3 . The biggest reiterated trunk was 1.1 m in diameter and 17 m long, which is larger than most adult Araucaria trees. Number of cavities and number of reiterated trunks were all significantly related to the diameters of these large remnant Araucaria trees; both features are absent in Araucaria <50 cm in diameter. The maximum diameter and average length of reiterated trunks were correlated with the number and size of trunk cavities. Commercial wood values and uses are limited for all trees with main trunk diameters exceeding 1.5 m due to large internal cavities -however, these rare, relictual old-growth structures are of high ecological value for the local fauna and flora.
This study was conducted in a commercial forest stand of Pinus taeda L. located in Curitibanos, in the State of Santa Catarina, Brazil. The objective of this study was to evaluate the influence of the physical barrier caused by the deposition of aciculas, on natural regeneration mechanisms of native species in sub-woods of P. taeda L. forest stand. Three plots (10 x 10 m) were installed in the sub-woods of the forest stand, and the natural regeneration was evaluated in the control (presence of aciculas) and clean (absence of aciculas) subplots, in addition to the seeds rain and soil seeds bank. The density and frequency parameters (absolute and relative) and the Shannon-Weaver Index (H’) were calculated, and the total density values of the seeds rain and seeds bank were subjected to ANOVA (p<0.05), while the density of regenerative seedlings was subjected to Student’s t Test (p<0.05), using the Software R Studio ®. The density of regenerative seedlings (ind.m-2) was higher in clean subplots, statistically. No significant statistical difference was observed for the density parameter (ind.m-2) among the subplots for the soil seeds bank, but only for the seeds rain. Shannon Diversity Index was higher in the plots closer to the fragment in all evaluated mechanisms. The obtained results indicate that the litter layer acts as a physical barrier to the breeding of the seeds bank and prevents the arrival of the seeds rain propagules directly to the soil, hindering the establishment of native plants and, consequently, the natural regeneration in the sub-woods.
Este estudo objetivou caracterizar a arborização do campus do Centro de Ciências Agroveterinárias da Universidade do Estado de Santa Catarina (CAV/Udesc), em Lages (SC). Realizou-se inventário quali-quantitativo das árvores e arbustos, em que se avaliaram estágio de desenvolvimento, fenologia, fitossanidade e poda e se calcularam os parâmetros de frequência absoluta e relativa para cada espécie. Foram encontrados 578 indivíduos, de 91 espécies e 37 famílias botânicas. A família Fabaceae foi a mais representativa. Em relação à origem, 63,7% das espécies são nativas do Brasil (73% dos indivíduos). Entre as espécies exóticas, destaca-se Ligustrum lucidum, com elevada frequência relativa. Quanto ao estágio de desenvolvimento, a maioria dos indivíduos está em estágio regular (60%) e jovem (38%), com poucos indivíduos cortados e mortos. A maioria dos indivíduos possui boa quantidade de folhas (81%), ausência de flores (93%) e ausência de frutos (83%). Observouse baixa incidência de cupins, fungos e epífitas, contudo salienta-se a presença expressiva de erva-de-passarinho em algumas espécies. A maioria dos indivíduos avaliados não sofreu podas (60%), estando a maior parte deles em condição boa ou satisfatória. Concluiu-se que a arborização do campus apresentou considerável riqueza de espécies, com poucos problemas graves, podendo ser caracterizada como heterogênea, em virtude da distribuição uniforme dos indivíduos entre as espécies.
Biological invasion is a major threat to global biodiversity and ecosystem services. We examined the functional traits similarity between a set of native and nonnative invasive tree species from the Southern Brazilian subtropical mixed forest, part of an important global hotspot for biodiversity conservation. We hypothesized that invasive species occupy marginal niche spaces. We ordered the species using the Principal Component Analysis based on their wood density, leaf area, and specifi c leaf area. These are all important traits that summarize essential ecological strategies associated with resource acquisition and conservation. Functional overlaps between non-native and native species were analyzed through kernel density estimation of continuous traits data. While native and non-native invasive species were distributed along the same functional gradients, the position of non-native species in the functional space is species and traits specifi c. We concluded that within Brazilian subtropical mixed forests, the functional dissimilarity as a key factor in invasion success could not be generalized for all species and traits.
RESUMO: Frente a crescente demanda por projetos de restauração florestal no Brasil, a definição de um conjunto de espécies adequados para a restauração florestal torna-se fundamental para o planejamento da restauração florestal em âmbito local e regional. Desse modo, o objetivo deste estudo foi definir espécies prioritárias para uso em projetos de restauração florestal na Floresta Ombrófila Mista Montana (FOMM) e Altomontana (FOMA), baseando-se nos valores de conservação e na classificação em grupos funcionais de diversidade e recobrimento. Para selecionar as espécies prioritárias foi utilizado o método de classificação por ranqueamento das espécies de ocorrência na região fitogeográfica de interesse. Três parâmetros foram utilizados: síndrome de dispersão; status de conservação; e endemismo. Após o ranqueamento as espécies foram classificadas em dois grupos: espécies de recobrimento e espécies de diversidade. Para a FOMM observou-se 35 espécies de recobrimento e 145 de diversidade, enquanto na FOMA verificou-se 23 espécies de recobrimento e 123 de diversidade. Para o grupo de diversidade, em ambas as formações avaliadas, estão entre as espécies de maior valor de conservação: Araucaria angustifolia e Dicksonia sellowiana. A espécie de maior valor de conservação pertencente ao grupo de recobrimento em ambas as formações foi Inga lentiscifolia. A presente lista pode servir como subsídio para o planejamento de projetos de restauração florestal e produção de mudas nativas na região da Bacia Hidrográfica do Rio Canoas e em outras regiões inseridas nestas formações florestais.
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