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- Genetic variability of Araucaria angustifolia Bertol. initial growth: subsidy to the formation of seed orchardsPublication . Gerber, Dionatan; Brun, Eleandro José; Topanotti, Larissa Regina; Ferreira, Josângela de Jesus; Porrua, Douglas; Gorenstein, Maurício Romero; Wagner, AméricoThe species Araucaria angustifolia Bertol. is native from Brazil, and it is now an endangered species due to the anthropic actions for several years. The objective of this study was to evaluate the genetic variability of Araucaria angustifolia based on initial growth qualitative and quantitative variables in a provenance and progeny test. Based on this performance, the genotypes with higher presence of superior characteristics were selected, to subsidize the formation of seed orchards. The matrices from Guarapuava-PR and Palmeira-SC were chosen according to their biometric and morphometric characteristics. Each matrix received a control code card. The matrices trees were assessed according to dendrometric and sanitary characteristics, and the harvested pine cones were evaluated for their weight, volume, and sanity. A total of 14 matrices from Palmeira-SC and 10 matrices from Guarapuava- PR were selected. The pinecones from each selected matrix were evaluated by quantitative characters. The seeds of these pineconeswere separated according to matrix tree, and they were used in the experiment to evaluatethe emergency and initial growth among genotypes.All the statistical analyses were conducted in a computational application about genetics –GENES® and on the software R Studio. It was verified that there is genetic variability among the provenances and progenies for most of the quantitative characters studied for A. angustifolia, and thus, there is also the possibility of obtaining gains through selection among and within the provenances. The selection among and within the provenances suggests that it is possible to reach significant genetic gains, especially for weight and diameter of pine cones, weight, and number of seeds per pinecone, and tree growth.
- Evaluating tree survival and modeling initial growth for Atlantic Forest restorationPublication . Gerber, Dionatan; Bechara, Fernando Campanhã; Topanotti, Larissa Regina; Nicoletti, Marcos Felipe; Azevedo, JoãoEcological restoration has become an important complementary practice to protect natural resources and preserve biodiversity. However, native species may be used in restoration programs in ways that do not optimize their performance. This research evaluated the survival and to model the initial growth of 15 native tree species planted in “filling” and “diversity” lines in the post-planting phase of a restoration experiment in the subtropics of the Brazilian Atlantic Forest. We measured survival rate (%) one year after planting and collar diameter (mm), total height (m), crown projection area (m²) and crown volume (m³) in the first 48 months after planting. Growth modeling for each variable and species was based on the non-linear mathematical Logistic, Gompertz, and Chapman-Richards models. Model selection for each variable/species was supported by the Akaike Information Criterion, standard error of the estimate, and coefficient of determination. The highest survival rates were reported for Cordia americana, Gochnatia polymorpha, Inga uruguensis, Peltophorum dubium, Prunus sellowii e Zanthoxylum rhoifolium (91.7%) and for Solanum mauritianum (90.3%). The species with faster growth were, by increasing order, Mimosa scabrella, Trema micrantha, Solanum mauritianum and Croton urucurana. With a better understanding of the initial developmental potential of tree species, it is possible to increase the species and functional diversity of the filling group. There was no single model capable of describing the variables analyzed and different models were needed to describe different characteristics and species.
- Performance of Guazuma ulmifolia Lam. in subtropical forest restorationPublication . Gerber, Dionatan; Topanotti, Larissa Regina; Gorenstein, Maurício Romero; Vieira, Frederico Márcio Corrêa; Stolarski, Oiliam Carlos; Nicoletti, Marcos Felipe; Bechara, Fernando CampanhãWe evaluated the initial development of Guazuma ulmifolia Lam. in a reforestation experiment in the southwestern region of Parana State, Southern Brazil. In a 70 native tree species plantation (3x2 m spacing) data were collected biannually, up to 48 months, from 72 individuals of Guazuma ulmifolia. The species performance was evaluated regarding its survival (96%), root collar diameter (6.79 cm), total height (12.84 m), crown projection area (14.36 m2) and crown volume (49.86 m3). The species growth at the age of 48 months, associated to its high survival and sprouting rates, tells of excellent behavior in the region, and it could be highly recommended as a shading species for fast canopy fulfillment in forest restoration projects, especially in regions with frost occurrence.
- Invasiveness, monitoring and control of hakea sericea: a systematic reviewPublication . Jacobson, Tamiel K.B.; Gerber, Dionatan; Azevedo, JoãoSolutions for ecological and economic problems posed by Hakea sericea invasions rely on scientific knowledge. We conducted a systematic review to analyze and synthesize the past and current scientific knowledge concerning H. sericea invasion processes and mechanisms, as well as monitoring and control techniques. We used ISIWeb of Science, Scopus, and CAPES Periodicals to look for publications on the ecological and environmental factors involved in H. sericea establishment (question 1); responses of H. sericea to fire in native and invaded ecosystems (question 2); and H. sericea monitoring and control methods (question 3). We identified 207 publications, 47.4% of which related to question 1, mainly from Australia and South Africa, with an increasing trend in the number of publications on monitoring and modeling. The traits identified in our systematic review, such as adaptations to dystrophic environments, drought resistance, sclerophylly, low transpiration rates, high nutrient use efficiency, stomatal conductance and photosynthetic rates, strong serotiny, proteoid roots and high post-fire seed survival and seedling recruitment, highlighted that H. sericea is a successful invader species due to its long adaptive history mediated by an arsenal of ecophysiological mechanisms that place it at a superior competitive level, especially in fire-prone ecosystems. Integrated cost-effective control methods in selected areas and the incorporation of information on the temporal invasion dynamics can significantly improve invasion control and mitigate H. sericea impacts while maintaining the supply of ecosystem services in invaded areas.
- Initial growth performance of valuable timber species in southern Brazil: Araucaria Angustifolia, Balfourodendron Riedelianum, and Parapiptadenia rígidaPublication . Topanotti, Larissa Regina; Gerber, Dionatan; Stolarski, Oiliam Carlos; Trentin, Bruna Elisa; Pertille, Carla Talita; Schorr, Luís Paulo Baldissera; Gorenstein, Maurício Romero; Nicoletti, Marcos Felipe; Bechara, Fernando CampanhãThe initial growth of three Brazilian native timber species in the city of Dois Vizinhos-PR, Brazil, was described - Araucaria angustifolia, Balfourodendron riedelianum, and Parapiptadenia rigida, using four non-linear mathematical models (Gompertz, Logistic, Logistic 4P, and Chapman-Richards). In the fi rst 4 years after planting, information about collar diameter (mm), total height (m), crown height (m), and crown diameter (m) was obtained twice a year for 12 individuals per species. Crown area (m²) and crown volume (m³) were estimated. The growth in these four variables (collar diameter, total height, crown area, and crown volume) was projected using the models, and their fi tting was assessed based on the values of the Akaike Information Criterion, the Bayesian Information Criterion, the standard error of estimate, and the coeffi cient of determination. The models generated excellent statistics for all parameters in all variables, with better statistics for collar diameter (coeffi cient of determination higher than 0.65 and standard error lower than 30%) and total height (coeffi cients of determination higher than 0.72 and standard error lower than 37%). Considering the three species, Parapiptadenia rigida
- Hakea decurrens invasion increases fire hazard at the landscape scalePublication . Gerber, Dionatan; Azevedo, João; Nereu, Mauro; Oliveira, Aline Silva de; Marchante, Elizabete; Jacobson, Tamiel Khan Baiocchi; Silva, Joaquim S.Hakea decurrens subsp. physocarpa is an invasive fire-adapted shrub of Australian origin that is quickly expanding in Portugal with potential impacts on fire behavior and fire regime. In this study we examined the effects of H. decurrens on fire hazard by assessing fire behavior indicators at the landscape scale, using a modeling and simulation approach. Six fuel models for H. decurrens were developed through fuel characterization and experimental fires. The fuel models correspond to combinations of developmental stages of H. decurrens populations (Early, Intermediate and Mature) and management (Standing and Slashed fuels). These combinations were used with three levels of H. decurrens invasion, corresponding to 25%, 50% and 75% of cover of the landscape, applied to five real landscapes in northern Portugal (replicates) under three fuel moisture conditions (Low, Medium and High), used as surrogates of weather severity. Fire behavior simulations were conducted with FlamMap software. The relationships between fire behavior indicators (flame length, rate of spread and burn probability) at the landscape level and the four factors tested were analyzed using Generalized Linear Mixed Models. Standing fuels were found to be more hazardous than slashed fuels. Fire-hazard increased with H. decurrens stand maturity and slash, regardless of moisture conditions. The results of this study indicate that H. decurrens expansion might negatively affect the fire regime in the north of Portugal. Our findings add to other known negative impacts of the species on native ecosystems, calling for the need to reinforce its control.
- Modelação do crescimento inicial de espécies arbóreas utilizadas em restauração florestalPublication . Gerber, Dionatan; Azevedo, João; Bechara, Fernando Campanhã; Nicoletti, Marcos FelipeA restauração de ecossistemas degradados representa um desafio em iniciar um processo de sucessão, principalmente quando as atividades antrópicas ocasionaram severas alterações nas características das formações florestais originais de um determinado local. O objetivo deste trabalho foi avaliar e modelar o crescimento inicial e sobrevivência de 15 espécies arbóreas nativas do Brasil em área de restauração florestal, utilizando três modelos matemáticos não lineares (Logistico, Gompertz e Chapman-Richards). Ao longo de um período de 48 meses após plantio, foram avaliados diâmetro do colo (mm), altura total (m), área de projeção de copa (m²), volume de copa (m³) e sobrevivência. A seleção do modelo mais adequado para cada espécie e variável avaliada teve como base o Critério de Informação Akaike, Critério de Informação Bayesiano, erro padrão da estimativa e coeficiente de determinação. Os modelos geraram excelentes estatísticas para todos os parâmetros em todas as variáveis, com melhores estatísticas para diâmetro de colo e altura total. O percentual de sobrevivência foi elevado para a maioria das espécies, com destaque para S. mauritianum, C. americana, G. polymorpha, I. uruguensis, P. dubium, P. sellowii e Z. rhoifolium. As espécies que se destacaram no crescimento em diâmetro do colo, altura total, área de projeção de copa e volume de copa, foram M. scabrella, I. uruguensis, Z. rhoifolium, C. urucurana, S. terebinthifolius, P. dubium, T. micranta, C. floribundus, S. mauritianum e G. ulmifolia, espécies altamente recomendadas em ambientes com condições ambientais semelhantes aos da área estudada. Com base nos resultados recomenda-se realizar o monitoramento a longo prazo para caracterizar melhor o comportamento do crescimento das espécies avaliadas no ecossistema em restauração.
- Vegetation and seed bank of an open-scrub bush restinga formation in the southeastern coast of BrazilPublication . Bechara, Fernando Campanhã; Salvador, Lívia Zocatelli; Ventura, Raquel Almeida; Topanotti, Larissa Regina; Gerber, Dionatan; Cruz, Izaclaudia Santana da; Simonelli, MarceloRestingas are coastal plain ecosystems located along Eastern Brazil, corresponding to about 5 000 km. The restinga vegetation is associated with the Atlantic rainforest biome and comprises four distinct main formation zones: coastal grasslands, shrublands, open-forests and marsh zones. Especially due to coastal urbanization, this is a threatened ecosystem that, through its different shrub formations, exhibits a unique mosaic as a result of the vegetation distribution in nuclei of different covering, physiognomy and floristic composition. Objective: We aimed to characterize the above and belowground composition of a conserved, non-flooded, open-scrub, nuclei (patches of bushes) formation of restinga in Linhares, ES, southeastern Brazil. Methods: The vegetation survey was conducted using the line intercept method. Diameter and height of the first six nuclei were measured in five transects separated by 50 m, totaling 30 nuclei up to 350 m away from the shore line. The phytosociology and Shannon Index of the aboveground vegetation community were calculated. In the same 30 nuclei, leaf litter and topsoil layer (15 x 15 x 10 cm) samples were collected to survey the viable seed bank, which was later placed in a greenhouse for germination and seedling identification. The Sørensen Similarity index (SSi) was used to compare the floristic composition between the leaf litter and topsoil layer seed banks. Nuclei volume and number of species were calculated as well. Results: In the aboveground vegetation, 54 plant species belonging to 32 families were identified, totaling 1 098 individuals. The nuclei showed a diversity (H’) of 3.08 nats, and an average diameter of 11.5 m (s = 9.1), area of 526.4 m2 (s = 1 081.7), and height of 2.9 m (s = 1.1). Davilla flexuosa, followed by Smilax rufescens, presented the highest IVI (Importance Value Index). A total of 1 839 seedlings from 32 species and 19 families were identified in the seed bank. Enydra sessilis (Asteraceae) had the highest seed density (544), while the family with highest species richness was Cyperaceae. A low similarity between the vegetation surveyed and the seed bank composition was found (only 5 species in common, SSi = 0.10). Conclusions: The results indicate that a post-disturbance early community, established from the seed bank, would have a substantially different species composition, but with other potential species to restore vegetation over the long-term succession.