Isabel Homczinski

The main concern of forestry companies is to accurately estimate the productivity of their stands, as well as to characterize their areas of greatest productivity. With the advancement of technology, GIS (Geographic Information System) tools have gained space in forestry planning. In this research, the objective was to simulate the growth and productivity in a Pinus taeda L. plantation, evaluate its productive capacity through site curves and perform site interpolation through GIS tools. The study area of ​​this research was a P. taeda plantation composed of three ages (six, eight and nine years). A forest inventory was carried out in which 33 circular sampling units of 400 m² each were installed, randomly distributed throughout the area. For the analysis of growth and productivity, 32 trees of mean quadratic diameter (dg) were felled and for the analysis of the site index, 33 dominant trees (Hdom) were felled and the trunk analysis was performed. Growth and productivity predictions were adjusted to the Chapman-Richards model. The site index was obtained by adjusting the Schumacher model, while spatial interpolation of site classes was generated using Kriging. Growth and productivity predictions allowed determining the correct age for silvicultural interventions and the technical age of cutting, as well as the productive capacity of the area. Seven site curves were identified in the study area. The use of GIS tools allowed defining which areas are the most productive.

The objective of this study was to analyze three strategies for fitting hypsometric models for Pinus taeda stands with different spacings. Data from a forest inventory containing 100 trees (5 stands x 4 plots x 5 trees) were used. Four hypsometric models were tested at the plot-level. The selected model was used in the individual adjustment, verifying the significance of the inclusion of the variables of sociological position, uniformity index and number of trees per hectare (strategy 2). In the model selected in strategy 2, the inclusion of a random effect parameter at the plot level was verified. The validation of the recommended model was carried out using the bootstrap method. All adjustments resulted in accurate estimates of total height, with RMSE and MAE values lower than 1.20 m and 0.98 m, respectively, considering an average total height of 20.1 m. In strategy 1, model (1) was selected. In strategy 2, the inclusion of sociological location and number of trees per hectare was significant and improved the estimates. In strategy 3, the inclusion of the random effect at the plot level further improved the model of strategy 2. The generalized mixed effects model was validated by the bootstrap method, and accurate estimates were presented in a short range. It is concluded that generalized mixed modeling is recommended and provides a unique fit for the five planting distances considered.

The aim of this study was to analyze volume yield, number of logs per assortment and economic feasibility of Eucalyptus dunnii stands under different management regimes. The stands are located in Fernandes Pinheiro, Paraná State, Brazil and cover a total area of 2.26 hectares, fragmented into three strata (treatments): A (8 years after coppicing regime), B (9-year old stand after two thinnings), and C (7-year old stand after one thinning). Diameters at breast height (d) of all trees and heights of 110 trees were obtained. The total height of the other trees was estimated by a hypsometric relationship. Tree volume was obtained through a taper function. For the economic analysis comparing the three strata, the periodic equivalent value (PEV) and the internal return rate (IRR) were evaluated considering an interest rate of 8%. The commercial volumetric estimates ranged from 156.61 to 375.53 m³ ha⁻¹. The stratum A yielded more logs, mostly for energy; stratum B yielded larger logs, and stratum C yielded similar number and volume of logs from all assortment classes. For economic analysis, PEV ranged from R$ 196.16 to R$ 1,255.79 ha year⁻¹, and IRR ranged from 12.73% per year (stratum A) to 21.35% per year (stratum C), based on a interest rate of 8%. It was concluded that the management condition of stratum C resulted in higher economic returns, with its product primarily destined for Sawmill 1.

Urban and peri-urban fragments are vital for biodiversity conservation, requiring genetic assessment of tree species in fragmented forests. The aim of this study was to analyze the genetic variability and diversity for adult individuals of J. micrantha along an urban-rural gradient in the Araucaria Forest. Fifteen individuals were sampled, with five from each remaining forest type. Initially, 10 ISRR primers were tested. Five mother trees were chosen from each site (urban, peri-urban, and rural) with a minimum distance of 100 m. The experimental design was a RCBD with 15 progenies, three provenances, three blocks, and 20 plants per plot, totaling 900 seedlings.

O lodo de esgoto é um subproduto do tratamento de esgoto, e seu destino é a incineração ou armazenamento em aterros sanitários, mas pode ser usado na agricultura como fertilizante. Esta pesquisa objetivou avaliar a importância do uso do lodo de esgoto como fertilizante do solo em plantios florestais de espécies madeireiras. A metodologia que se mostrou mais adequada para o desenvolvimento deste estudo foi a pesquisa bibliográfica sistemática, realizada em artigos científicos publicados entre os anos de 2013 a 2023. O uso do lodo de esgoto em plantios florestais acelera e aumenta a produção de madeira e biomassa, além de trazer benefícios nutricionais. A sua utilização como fertilizante também traz benefícios ao meio ambiente, pois evita sua deposição em aterros sanitários ou a sua incineração e fornece retorno financeiro para a empresa que trata os efluentes e para empresa florestal, já que minimiza os gastos com fertilizantes convencionais. Palavras-chave: madeira; biossólido; fertilização.

Prunus campanulata is a species largely adopted for landscape composition in Brazil with limited seedling production by seed dormancy, lacking studies about in vitro propagation. This study aims to evaluate different P. campanulata seed pretreatments on germination, and the effect of GA3 on dormancy break and seedlings biometry. Seeds were processed in three treatments: complete seeds, seeds without endocarp, and isolated zygotic embryos incubated in a WPM medium containing different GA3 concentrations (0.0, 2.0, and 4.0 mg L-1). After 30 days of in vitro incubation were evaluated the germination percentage, mean germination time, percentage of normal seedlings, percentage of seedlings with leaves, and survival percentage were. Seedlings greater than 3.0 cm were selected for ex vitro adaptation, evaluating after 32 days the biometric variables: total length, aerial part length, root length, and the number of leaves. Complete seeds do not germinate, suggesting dormancy associated with the endocarp, whereas seeds without endocarp and isolated zygotic embryos showed the same germination rate, with no effect on GA3. The GA3 promoted greater seedling growth at concentrations between 1.89 mg L-1 for the total length of the isolated zygotic embryo and 2.24 mg L-1 for the length of the aerial part of seeds without endocarp. In conclusion, seed processing, i.e., removing the endocarp or isolating the zygotic embryo can overcome dormancy, improving germination and seedling production of P. campanulata in vitro.

Understanding how a particular species grows and factors that affect its growth are relevant in ecological studies, especially when one intends to manage a particular species. Thus, this research aimed to evaluate the spatial distribution, phytosociology dynamics and competition of E. involucrata, to characterize floristic composition and phytosociology of the associated community and to observe relationship between species growth and competition in order to propose and validate diameter growth models for the species. This research was developed at Irati National Forest, Parana state in 25ha permanent plots, with inventory data from 2002 to 2017. To characterize the specie, the spatial distribution, phytosociology, and dynamics (increment, mortality and ingress) data were evaluated. Characterization of associated community was carried out in 111 plots of 100m², evaluating floristic composition, phytosociology, and competition, and later, growth models were proposed at individual trees level. The species showed aggregate spatial distribution, slow growth diameter, and an ingress rate greater than the mortality rate. The species most associated with E. involucrata were Araucaria angustifolia, Ilex paraguariensis and Ocotea odorifera. E. involucrata trees in smaller DBH classes (10 to 20cm), suffered more competition from associated community. Variables initial DBH and initial cross-sectional area were most correlated with final diameter, and these were variables that had best fit for diameter growth models for individual trees. This research provides relevant information about ecology of this species and its associated communities very useful for future research for the species.