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CERNE, Volume: 27, Publicado: 2021
  • Seasonally dry tropical forest temporal patterns are marked by floristic stability and structural changes Forest Ecology

    Souza, Cléber Rodrigo de; Santos, Alisson Borges Miranda; Maia, Vinícius Andrade; Paula, Gabriela Gomes Pires de; Fagundes, Nathalle Cristine Alencar; Coelho, Polyanne Aparecida; Santos, Paola Ferreira; Morel, Jean Daniel; Garcia, Paulo Oswaldo; Santos, Rubens Manoel dos

    Resumo em Inglês:

    ABSTRACT Background: Seasonally Dry Tropical Forests (SDTF) are recognized by their great biological diversity, but little is known about their temporal patterns, which may be crucial in a changing world. Here we aimed to characterize the SDTF dynamic patterns in floristic and structural changes, and also to evaluate shifts in dynamic rates and structural attributes such as richness, number of trees and biomass. Our hypothesis is that SDTF tree communities have their dynamic characterized by temporal fluctuations related to an instability pattern, in according to the already found for others tropical forests. For this we used a data of 42 400 m² plots in three fragments in the Brazilian Arboreal Caatinga, measured in 2005, 2010 and 2015. We evaluated temporal changes in richness, species composition, trees density, biomass and rates of tree mortality and recruitment; and also rates of biomass gain and loss. Results: We found a pattern of floristic composition stability, but with changes in structure and dynamics. There was a tree density decrease driven by constant mortality and by recruitment decrease, and biomass increase due to decrease in biomass loss and to increase in biomass gain. The biomass increase was main related to a small set of dominant species that are the most representative in the community dynamics. Conclusion: SDTF dynamics are related to stability in species composition, but with structural changes towards higher biomass stocks. The results are main related to community dynamics and to SDTF attributes such as climatic seasonality that drives the local ecological processes.
  • Canopy recovery four years after logging: a management study in a southern brazilian secondary forest secondary forest Forest Ecology

    Likoski, Janine Kervald; Vibrans, Alexander Christian; Silva, Daniel Augusto da; Fantini, Alfredo Celso

    Resumo em Inglês:

    ABSTRACT Background: Understanding forest dynamics after logging is essential to define forest management cycles and intensities. In secondary forest, especially in the Atlantic Forest Domain, these studies are still scarce. Monitoring of the canopy structure after tree harvesting can be performed by hemispherical photographs, where canopy opening is commonly analyzed. This study evaluated changes in canopy opening four years after tree harvesting in a secondary Atlantic Rainforest in southern Brazil. We used hemispherical photographs to determine the Canopy Openness (CO), Leaf Area Index (LAI), and Diffuse Fraction of Photosynthetically Active Absorbed Radiation (FAPARdif) in eleven permanent plots. Results: We found that harvesting resulted in a momentary increase in canopy opening and light availability in the understory. Four years after harvesting, CO, LAI and FAPARdif recovered or even exceeded the original values of the forest. We observed a significant correlation between CO and number of trees harvested with DBH > 30 cm. Weak correlations were found between these canopy related variables and the logging intensity. Conclusion: In conclusion, we recognized that changes of CO, LAI and FAPARdif after timber harvesting presented short duration. This indicates that the applied logging intensities, 21.8 to 51.1% of the total basal area, did not exceed the resilience of the forest canopy and it’s recovering four years later. However, additional studies should be carried out to observe vegetation dynamics, such as species composition, vertical structure, productivity and community stability, in order to improve management schemes of secondary stands in the Atlantic Forest.
  • Study on rare and endangered plants under climate: maxent modeling for identifying hot spots in northwest China Forest Ecology

    Zhang, Hua; Zhao, Haoxiang

    Resumo em Inglês:

    ABSTRACT Background: Climate warming has caused substantial changes in temporal and spatial environmental patterns. The study on hot spots of rare and endangered plants in Northwest China under predicted climate change can provide a scientific reference for the restoration and reconstruction of those degraded habitats, as well as the improvement of the protection system in Northwest China. Results: Based on MaxEnt algorithm, 813 effective distribution records and 11 environmental factor variables of rare and endangered plants in Northwest China, this study identified the changes of biodiversity hotspots of rare and endangered plants in Northwest China under predicted climate change. The results showed that: (1) the prediction accuracy of MaxEnt model is high, the area under the curve (AUC) is 0.876, and the total suitable area for potential geographical distribution of rare and endangered plants in Northwest China is 137.96×104km2, mainly including Western and Southwestern Xinjiang, Southern Gansu, parts of Eastern and Southern Qinghai Province, and Southern Shaanxi Province; (2) altitude, temperature and precipitation are the main environmental factors affecting the hot spots of rare and endangered plants in Northwest China; (3) under four climate change scenarios in the future, with the increase of emission scenarios from low to high forcing, Xinjiang would have the most obvious loss of hot spots of rare and endangered plants in Northwest China, and the most obvious increase of which would occur in Qinghai and Gansu provinces. Conclusion: Under the climate change scenario in the future, with the emission scenario increasing from low forcing to high forcing, the most obvious loss of the hot spots of rare and endangered plants in Northwest China happens in Xinjiang Province, and that of the most obvious increase occurs in Qinghai and Gansu provinces.
  • Potential distribution of two lynx species in europe under paleoclimatological scenarios and anthropogenic climate change scenarios Forest Ecology

    Kiraç, Akin

    Resumo em Inglês:

    ABSTRACT Background: Today’s European fauna was formed under the influence of Paleoclimatic change. The distribution of two wild cat species of Europe, Lynx pardinus and Lynx lynx, 22,000 and 6,000 years ago were determined by the MaxEnt method in relation to the Paleoclimatological scenarios (LGM and Mid-Holocene) and fossil records. Then, the current climate conditions and their distributions under the effect of anthropogenic climate change scenarios were analyzed with the current existence records. Results: It was determined that these two wild cats were distributed according to preys on which they specialized, rather than the climate change that lasted for thousands of years. It was observed that Lynx Pardinus, which specialized only on European rabbit hunting, could not expand its distribution from past to present. Lynx lynx, on the other hand, expanded its distribution throughout the Palearctic region and adapted to different ecosystem varieties by means of its specialization on many preys from mouse to moose. Based on the climate envelope model results created with the help of MaxEnt which considers anthropogenic climate change scenarios (RCP2.6, RCP4.5, RCP6.0 and RCP8.5 2070) and today’s data of two existing Lynx species, suitable habitats for L. pardinus will decrease and suitable habitats will emerge in Western France. L. lynx, on the other hand, will limit its wide distribution to the North, except for the Alps, the Carpathians and the Caucasus, which will serve as refugial areas. Conclusion: These results therefore require that measurements such as reducing climate change impacts over the next 50 years, protecting existing and potential habitats in advance, and reducing anthropogenic impact should be enforced.
  • Effects of land use and topographic variables on distribution of pine mistletoe (Viscum álbum subsp. austriacum (Wiesb.) Vollm.) in northeastern Turkey Forest Ecology

    Usta, Ayhan; Yılmaz, Murat

    Resumo em Inglês:

    ABSTRACT Background: This study evaluated the distribution of pine mistletoe in Scots pine ecosystems in relation to topographic variables and land uses. A total of 109 sample plots were selected from pure Scots pine forests in the Eastern Black Sea Region of Turkey. The 6-class dwarf mistletoe rating was used for infection severity. Pearson correlation analysis results showed significant relationships between mistletoe infection severity and topographic variables in 30 m buffer and land use in 500 m buffer. Results: Of the sample plots, 69 (63%) were mistletoe infected, and 40 (37%) were uninfected. The t-test results showed that there was a significant difference between mean topographic variables and land use in mistletoe infected and uninfected sample plots. The results of the binary logistic regression analysis showed that altitude, productive forest, slope, and road distance were the most significant predictors of the distribution of pine mistletoe as topographic variables and land uses. Conclusion: The common direction of mistletoe infected areas, in addition to Scots pine ecosystems, was low altitudes, sheltered valleys, more humid areas and different land use (agriculture, road and stream).
  • Distribution and importance of some endemic Astragalus L. species in semi-arid environmentally sensitive areas: a case study from northern Turkey Forest Ecology

    Gül, Ebru; Dölarslan, Melda

    Resumo em Inglês:

    ABSTRACT Background: The objective of this study was to determine the distribution of some endemic species of the genus Astragalus L. (Astragalus anthylloides Lam., Astragalus lycius Boiss. and Astragalus xylobasis var. angustus (Freyn & Sint.) Freyn & Bornm.) species, and the interaction between soil, climatic characteristics and desertification risk which affect the distribution of these species in the semi-arid environment of Çankırı, northwest Turkey. During the vegetation period in 2017, soil and plant samples were collected from 180 points. Desertification risk (DR) and environmentally sensitive area index (ESAI) were calculated for each sampling point using the desertification indicator system for Mediterranean Europe (DIS4ME). Results: According to the DIS4ME system in the forest areas, DR values for A. anthylloides and A. lycius were lowest with 0.49 (no desertification risk) and highest with 3.73 (moderate desertification risk), and with an average of 2.20 in the field (low desertification risk). For A. xylobasis var. angustus in grassland, the DR values ranged from a low of 5.01 to a high of 5.42. The ESAI values ranged from 1.34 to 1.50 in the forest areas where the species A. anthylloides and A. lycius were distributed, and they ranged between 1.33 and 1.47 for A. xylobasis var. angustus in the grassland areas. The results of the analysis between the DR values and Astragalus L. species changes according to the land use types and plant distribution. Conclusion: When the relationships between all three of these endemic species’ DR values are evaluated together, they emerged as the best plant species indicator for determining desertification status.
  • Restoration potential of eight tree species from a seasonally dry tropical forest in southeast Piauí, Brazil Forest Management

    Ribeiro, Andressa; Ferraz Filho, Antonio Carlos; Farias, Séfora Gil Gomes de; Dias, Bruna Anair Souto; Silva, Helionai Pereira da

    Resumo em Inglês:

    ABSTRACT Background: The conservation and restoration of forest landscapes is an important aspect of sustainable development. In semi-arid regions these practices are difficulted by the harsh climate of these environments, with low precipitation values and prolonged dry seasons. The objective of this study is to identify tree species from the south of the Brazilian state of Piauí that have potential to be used in forest restoration programs. Results: Data from forest inventory and tree characteristics were used to select eight tree species using target species definition, focusing on species with desirable wood properties, abundance in the study region, favorable dendrometric variables, seed availability, ease of seed germination and seedling growth in nursery and field conditions, among others. These species were then evaluated as candidates for restoration using a framework species approach focusing on the following attributes: (i) 70% or higher seedling survival in the field; (ii) seedling height of 45 cm or taller after the first growing season in the field and (iii) 70% or greater nursery seedling survival. Conclusion: The species Combretum glaucocarpum, Cenostigma macrophyllum, and Pityrocarpa moniliformis are suitable to be employed in forest restoration programs in the southern region of Piauí, Brazil. Further studies must be carried out to assess the behavior of these and other potential tree species in long term field conditions and under varying silvicultural regimes, a key aspect for forest restoration.
  • Dendrometric characterization of Cupressus lusitanica mill. planted under Pinus taeda L. shelter in southern Brazil Forest Management

    Topanotti, Larissa Regina; Vaz, Douglas Rufino; Dobner Jr., Mário; Nicoletti, Marcos Felipe

    Resumo em Inglês:

    ABSTRACT Background: We analyzed if C. lusitanica can be planted in a shelterwood system with P. taeda as the shelter stratum. The study was conducted in a 13-yr-old C. lusitanica stand under P. taeda canopy in Southern Brazil. Samples of these trees were measured in terms of diameter at breast height (DBH), total height, individual volume, and crown projection area. The species´ growing space efficiency (GSE) was also analyzed. A 10-meters distance criterion from P. taeda trees was applied to check their influence on C. lusitanica growth behavior through correlation. Results: The 36-yr-old P. taeda trees showed expressive means in the dendrometric variables, compatible with its age (mean DBH of 58 cm, total height 30 m, individual volume of 3.7 m³, and crown projection area of 128 m²). There was a statistically significant effect (p>0.05) of P. taeda cover on C. lusitanica diameter (mean of ~13 cm). Although not significant, an effect of P. taeda canopy was also observed on C. lusitanica height. The two species summed a basal area of 36.5 m² ha-1 and a crown projection area of 34,209.2 m² ha-1. A tendency of increasing GSE with increasing diameter was observed for both species. Conclusion: These results show that a shelterwood with C. lusitanica under P. taeda is possible, but further investigations with longer production cycles and with silvicultural treatments (i.e. thinnings and shelter removal) should be conducted for a better understanding of shelterwood systems with these species in southern Brazil in terms of growth performance and soil use sustainability.
  • Segmented taper models form for Manchurian fir and Korean spruce in northeastern China Forest Management

    HUSSAIN, AMNA; SHAHZAD, MUHAMMAD KHURRAM; JIANG, LICHUN; LI, FENGRI

    Resumo em Inglês:

    ABSTRACT Background: Manchurian fir (Abies nephrolepis Maxim) and Korean spruce (Picea koraiensis Nakai) are primary conifer species of economic and ecological importance in northeast China. Several taper studies have analyzed for fir and spruce species in the countries harboring the boreal forests. However, taper models do not exist for Manchurian fir and Korean spruce in China or abroad. This study aimed to develop stem taper models for these species. A dataset of 188 destructively sampled trees (Manchurian fir 123 and Korean spruce 65) was used to evaluate eight well-known taper models. These models were fitted with generalized non-linear least squares by using 3,570 diameter and height measurements. We incorporated a first-order continuous-time error structure to adjust the inherent autocorrelation. Results: The form-class segmented model of Clark et al. (1991) best predicted the diameter, merchantable volume, and stem volume of the species when the upper stem diameter at 5.3 m was available or predicted. Conclusion: When diameter measurements at 5.3 m were not available, the Kozak (2004) and Max and Burkhart (1976) models were superior to other models in estimating the diameter of both species and volume of Korean spruce. For Manchurian fir, the Fang et al. (2000) model was more accurate in volume estimates.
  • Use of the process-based models in forest research: a bibliometric review Forest Management

    Gonçalves, Anny Francielly Ataide; Santos, Juscelina Arcanjo dos; França, Luciano Cavalcante de Jesus; Campoe, Otávio Camargo; Altoé, Thiza Falqueto; Scolforo, José Roberto Soares

    Resumo em Inglês:

    ABSTRACT Background: Process-based modeling is made to simulate the interactions of the soil-plant-atmosphere system providing information and estimates for forest management and services. Through bibliometric evaluation we identify the quantitative state of the art on the use of Process-Based Models (PBMs) applied in forestry studies, contextualizing research fronts, and analyzing the main topics and emerging themes. Data from the Web of Science and Scopus were used for the bibliometric survey of 533 scientific records. Results: We verified that (i) the number of publications related to the PBMs was boosted in the year 2000, and is growing; (ii) Forest Ecology and Management (74 publications) is the journal that most publishes on the subject; (iii) Annikki Mäkelä is the most productive researcher (20 publications) and most cited (h-index: 12); (iv) The USA (131 records) is the country with the highest number of research; (v) there are eight collaborative networks between the authors, three workings together, and five producing in isolation; (vi) the keywords are grouped into five clusters: (a) the effect of climate change on forests; (b) carbon studies; (c) physiology of trees; (d) silvicultural practices and; (e) analysis of model uncertainties. The separation of themes showed that the new search hotspots are the PBMs using of remote detection tools. Conclusion: The results presented can be a fundamental theoretical tool for understanding the trends and development perspectives of this research line in future studies.
  • Study on Forest Fire spread Model of Multi-dimensional Cellular Automata based on Rothermel Speed Formula Forest Management

    Zhang, Shiyu; Liu, Jiuqing; Gao, Hewei; Chen, Xiandong; Li, Xingdong; Hua, Jun

    Resumo em Inglês:

    ABSTRACT Background: The spread of forest fire is a complex natural phenomenon. The cellular automata(CA) is a common model of forest fire spread, which fails to combine the unique combustion properties of forest fire spreading, resulting in inaccurate simulation results. In order to improve the accuracy of forest fire spread simulation, the Rothermel forest fire rate formula is simplified and combined with CA to form a multi-dimensional cellular automata(MD-CA) model of forest fire spread with different combustion properties in each cell. The formulas of the spread rate of forest fire in eight directions are obtained through the training datasets, and the testing datasets are used to compare the simulation results of CA model, MD-CA model and the actual fire spread. Results: It is concluded that the simulated areas and perimeters of the MD-CA are closer to the actual forest fire spread, the area error rate is 9.42% - 15.63%, and the perimeter error is 4.21% - 8.99%, The errors are less than CA model. Conclusion: The MD-CA model based on Rothermel has the strong ability to simulate the spread of fire in the laboratory, however, how to eliminate the errors over time is the task of the next stage.
  • Mini-cutting of Plathymenia reticulata benth. with ministumps conducted in suspended seedbed and tubes Silviculture

    Carvalho, Giovanna Campos Mamede Weiss de; Pessanha, David Siqueira; Silva, Renata de Deus da; Silva, Maria Kalyane Farias da; Barroso, Deborah Guerra

    Resumo em Inglês:

    ABSTRACT Background: Despite the importance of Plathymenia reticulata for forestry and ecological purposes, a protocol for the vegetative propagation of the species remains unclear mainly due to the low adventitious rooting of the propagules of the species. In this sense, this work aimed to evaluate the rooting of mini-cuttings of juvenile materials of P. reticulata and our hypothesis: (1) maintaining propagules under mist chamber for different periods affects the rooting process; (2) the mini-stump management system due to the restriction of the root system affects the production of mini-cuttings and the quality of clonal seedlings. Results: It was not necessary for more than 30 days in a mist chamber to induce rooting. The highest percentage of rooting was obtained 50 days after staking. Mini-gardens set up in suspended seed bed and tubes (280 cm3) had the average mini-cuttings productivity of 4.32 and 2.06, respectively, over 270 days of exploration (monthly collections). At 120 days after staking, there was no difference in the survival and in the final quality of clonal seedlings produced. However, clonal seedlings from mini-garden in tubes had higher height, leaf area, and number of first-order roots. Regardless of the mini-garden management, the clonal seedling production index was 50%. Conclusion: We can conclude that P. reticulata seedling production via mini-cutting technique is possible.
  • Leaflet phenotypic plasticity in three woody species in two strata of a gallery forest Silviculture

    Santos, Jamile dos; Marenco, Ricardo Antonio; Ferreira, Wendy Carniello; Dias, Daniela Pereira

    Resumo em Inglês:

    ABSTRACT Background: Along the vertical canopy profile, natural light availability is variable and may induce leaves morphophysiological changes due to phenotypic plasticity. Morphological changes in juvenile and adult leaflet of compound leaves of plant species is still poorly understood, including in woody species of gallery forests. The present study evaluated the leaflet morphophysiological characteristics and plasticity index of three woody species in canopy and understory leaves in a gallery forest. Results: All morphophysiological characteristics varied within species (Myracrodruon urundeuva Allemão, Copaifera langsdorffii Desf. and Tapirira guianensis Aubl.). The leaflets of canopy trees showed significantly higher values of petiole length (PL) and diameter (PD), leaflet thickness (fresh - FT and dry - DT), specific leaf mass (SLM), in relation to understory leaflets. On the other hand, relative water content (RWC) did not change between adult trees and saplings, except for T. guianensis. The plasticity index of leaflet characteristics varied significantly within species. Plasticity index of three morphophysiological characteristics (PL, PD and DT) varied between species. PL and PD had the highest plasticity index values across species, whereas RWC had the lowest plasticity.. Conclusion: Plasticity index of the tree species associates these leaflet morphophysiological traits (PL, PD and DT) with variations in the physical environment between strata of a gallery forest.
  • Ratios between aboveground net primary production, litterfall and carbon stocks in scots pine stands (Russia) Silviculture

    Osipov, Andrey F.; Kutjavin, Ivan N.; Bobkova, Kapitolina S.

    Resumo em Inglês:

    ABSTRACT Background: Forests are the main terrestrial regulators of greenhouse gas concentrations. However, estimates of carbon fluxes in them are characterized by large uncertainties. Therefore, the derivation of predictors for their assessment is an urgent task. The aim was to assess the carbon stocks in the biomass to characterize the intensity of aboveground net production and the amount of litterfall in Scots pine forests of different types on the North-East of the Europe. We estimated biomass and aboveground net primary production (ANPP) of stands using sample trees. For vegetation of ground cover biomass and primary production evaluating, we cut off all aboveground organs on an area of 625 cm2 and removed the first-year parts. Litterfall was collected over 3-6 years using litter traps. Results: Most of the carbon in the biomass of pine forests is concentrated in trees (Cstand) with dominating role of stem wood. However, in boggy forests, ground vegetation plays a significant role in carbon stocks, both in absolute and relative values. We estimated carbon fluxes in ANPP and stand litterfall. High contribution of needles was detected for these flows. The ratio between ANPP and Cstand varied from 0.018 to 0.056 but between Litterfal and Cstand ranged from 0.008 to 0.024. Conclusion: The biomass, ANPP and litterfall depended form forest type. Obtained ratios between them can be used for assessing carbon fluxes in large regions using remote data collection of forest biomass.
  • Detection of high potential areas of persian oak forests decline in Zagros, Iran, using topsis method Silviculture

    Moradi, Mohammad Javad; Kiadaliri, Hadi; Kafaky, Sasan Babaie; Bakhoda, Hossein

    Resumo em Inglês:

    ABSTRACT Background: During the past decade, the phenomenon of Oak decline has affected valuable Zagros Oak Forests in western Iran. Quercus brantii as the most important tree species of these forests has been damaged more than any other species. Many factors are involved in this phenomenon. The purpose of this study was to identify areas with high potential for decline and determine the most important factors affecting it. In this study, using multi-criteria evaluation methods based on the Geographic Information System (GIS) Technique for Order of Preference by Similarity to Ideal Solution (TOPSIS) method and fuzzy logic, the map of decline potential of two selected stands (Dalab and Cheghasabz) in Ilam Province was prepared to reveal the high-risk areas of decline. The analytical hierarchical process was used to determine the weight of the factors. Results: The results showed that both selected stands had decline potential. However, the Dalab stand at 25% and the Cheghasabz, at approximately 60% of the stand has an extreme potential for decline. Rainfall factors, pests, and diseases also have the greatest effect on Oak forest decline. Conclusion: Due to socio-economic problems such as land use change, fire, tourism, grazing, and pruning, the Cheghasabz is more prone to decline than the Dalab, which was a forest reserve. The multi-criteria evaluation model used in the study can be a guide in identifying high-risk areas in other parts of the Zagros forests. The large area of critical areas in these two regions reveals the need for planning to implement support operations to reconstruct damaged ecosystems.
  • Genetic control of productivity and genotypes by environments interaction for Eucalyptus dorrigoensis in southern Brazil Silviculture

    Munhoz, Leonardo Vannucchi; Santos, Osmarino Pires dos; Valente, Brigida Maria dos Reis Teixeira; Tambarussi, Evandro Vagner

    Resumo em Inglês:

    ABSTRACT Background: Eucalyptus dorrigoensis withstands cold weather and the occurrence of frost, making it a potential species for improvement programs in Southern Brazil where such conditions occur. However, the use of the species is still uncommon and its genetic variability remains poorly understood.d. Results: For site called Sertão Santana, the narrow sense heritability ranged from 0.46 (H) to 0.64 (MAI) and for Lavras do Sul it ranged from 0.38 (H) to 0.47 (MAI). The coefficient of genetic variation varied from 8.1% (H) to 26.1% (MAI). There is significant genetic correlation between DBH and MAI, reaching a value of 0.97. The GxE interaction was significant and mostly complex (78.7%). The best genetic materials for each environment, along with the most stable genetic materials, were identified. In addition, a thinning simulation was performed and the genetic gains for Sertão Santana and Lavras do Sul were 12.62 and 7.43%, respectively. Conclusion: The studied populations have genetic variability that can be used in breeding programs by selecting among progenies and individuals within progenies. The GxE interaction is complex, and as such, the best genetic material should be selected independently for each site. The results of this study have practical implications for the companies and offer advances in knowledge of the species for breeding programs.
  • biochemical attributes and establishment of tree seedlings in soil after urochloa decumbens cultivation in soil with deposition of iron mining residues Silviculture

    Ribeiro Junior, Alexandre Carvalho; Silva, Aline Oliveira; Batista, Éder Rodrigues; Naves, Filipe Sales; Pinto, Flávio Araújo; Santos, Jessé Valentim dos; Barbosa, Marisângela Viana; Alvarenga, Ingrid Fernanda Santana; Carneiro, Marco Aurélio Carbone

    Resumo em Inglês:

    abstract background: the recovery of areas impacted by mining activities is a major challenge and requires knowledge of how the biological and biochemical processes of the soil as well as the establishment of plant species are affected by mining residue. in this work, the influence of deposition of iron mining mud and tailings on soil biochemical attributes and the initial development of tree seedlings was studied in a simulated event in the greenhouse. pots (n = 27) with natural soil (2.0 kg) received deposition (280 ml) of iron mining mud or tailings and by three-month was cultivated with urochloa decumbens. at the end of this period, part of the pots was sampled and the soil biochemical activities were evaluated. then tree seedlings (schinus terebinthifolius and eremanthus incanus) were planted and cultivated for a year, when then shoot (sdw) and roots (rdw) dry weight were evaluated. results: deposition of iron mining mud and tailings did not affect microbial biomass carbon or basal soil respiration, however both conditions reduced (p < 0.05) β-glucosidase activities by up to 30%, and the easy extractable glomalin by about 19%. in addition, the mud deposition reduced (p < 0.05) the sdw and rdw of s. terebinthifolius by about 21% and 24%, respectively. nevertheless, uruchloa decumbens and eremanthus incanus had no variation in dry weight production between treatments, so they have good ability to grow settle in soil affected by mining residue. conclusion: this study shows that the sequential planting of u. decumbens and e. incanus can be an alternative for use in environments with deposition of iron mining tailings.
  • Evaluation of biomass, carbon storage capability, agroforestry interest of Pinus pinea L. and management practices to increase carbon stocks: a review Silviculture

    Mechergui, Kaouther; Naghmouchi, Souheila; Altamimi, Amal Saleh; Jaouadi, Wahbi

    Resumo em Inglês:

    ABSTRACT Background: Stone pine (Pinus pinea L.) is one of the characteristic species of the Mediterranean flora. This species has been used since ancient times because of its economic importance. This study was carried out because stone pine forests in the Mediterranean area, as carbon sinks, are one of the mitigation strategies considered to face climate change. Also, stone pine forests are of great socio-economic importance on an international scale due to the high demand for pine nuts and the important role of this emblematic species in agroforestry. The objectives of this study are, firstly, the evaluation of biomass and carbon storage capability and, secondly, the study of agroforestry interest of Pinus pinea L. and management practices to increase carbon stocks. Results: A review of research and knowledge was carried out on the subject based on a selection of publications that have been made in the Mediterranean area. The main conclusions are that stone pine forests have a very high biomass stock and a high storage potential in the future. However, these forests could be a potential carbon reservoir in the coming years and thus on climate change mitigation. In addition, the practice of agroforestry in the stone pine ecosystem can create jobs and many sources of income for the local population and improve their living standards. Conclusion: Finally, this review of research results can serve as an initial basis for refining management practices to improve the establishment of pine trees and tools to help forest managers in quantifying biomass, thereby contributing to the accurate estimation of carbon sequestration and stocks in stone pine stands and agroforestry practices..
  • Technical feasibility of Eremanthus erythropappus (dc.) macleish coppice: critical factor for sustainable management Silviculture

    Pavan, Adriano José; Botelho, Soraya Alvarenga; Melo, Lucas Amaral de; Pavan, Vanete Maria de Melo; Terra, Marcela de Castro Nunes Santos

    Resumo em Inglês:

    ABSTRACT Background: This study aims to evaluate the technical feasibility of simple coppice system, in a planted stand of the native arboreal species Eremanthus erythropappus (DC.) MacLeish (candeia), according to different moments of soil scarification. The experiment is located in Baependi - MG (Brazil), where the mean altitude is 1,165 m and it´s under mild mesothermal climate. The first cycle was harvested under a clear-cutting system at 8 years after planting, with manual soil scarification and exposure of roots around the harvested trees stumps, at 5, 6, 7, and 8 weeks after cutting, i.e., four treatments with four repetitions of 50m2 plots each. In the first months, adventitious buds sprouting from the roots have been observed inside and outside the perimeter around stumps. The area remained fenced, without thinning or application of fertilizers and, until the third year, the selective clearing was done to eliminate weed competition. Six years after the treatment, measurements of diameter at 1.30 m height (DBH), the height of the sprouts, and the circumference at soil height (CSH) of stumps were taken. Results: After six years, the regenerated site under simple coppice system presented a density of established plants 216% higher than the harvested site using a high forest system (first cycle), but with only 4.3% of the commercial volume. The correlation between the density of sprouts and the density of stumps indicated that initial plant density can influence the number of sprouts after harvest. Conclusion: It was verified the simple coppice system feasibility and that scarification technique can be applied up to eight weeks after tree cutting.
  • Clonal micro-garden formation of Bambusa vulgaris: effect of seasonality, culture environment, antibiotic and plant growth regulator on in vitro culture Silviculture

    Teixeira, Giovanna Carla; Gonçalves, Douglas Santos; Modesto, Ana Cláudia de Barros; Souza, Denys Matheus Santana Costa; Carvalho, Dulcinéia de; Magalhães, Thiago Alves; Oliveira, Leandro Silva de; Teixeira, Gustavo Leal; Brondani, Gilvano Ebling

    Resumo em Inglês:

    ABSTRACT Background: We have developed a micropropagation technique methodology to clonal micro-garden formation of Bambusa vulgaris selected adult plant. Collection site (i.e., stock plant cultivated in different environments) and seasonality of shoot collection (i.e., months of the year) effects on in vitro culture were evaluated. Explants that showed normal development were ex vitro rooted in mini-incubator system, and three culture media (WPM, MS and deionized water + agar) supplemented with plant growth regulators (IBA, NAA and BAP) and antibiotic (streptomycin sulphate and culture medium free - control) were evaluated. Micropropagated plants were acclimatized in a shadow house and transferred to a semi-hydroponic system for establishment of a clonal micro-garden. The efficacy of the cloning protocol was determined with genetic fidelity analysis by ISSR molecular markers. Results: Considering all inoculations, 21.9% of nodal segments were in vitro established in nine shoot collections. The rooting percentage was 36.6%, and no interactions were observed between the use of culture medium and antibiotic. Culture medium free antibiotic resulted in 80.0% of survival and 50.0% of adventitious rooting. Micropropagated plants presented adequate growth and adaptation to ex vitro conditions in the clonal micro-garden. Molecular analyses by ISSR markers indicated the absence of genetic variations, and histological analyses revealed normal adventitious root formation originating from meristematic cells. Conclusion: The formation of a clonal micro-garden was demonstrated, proving the feasibility of the tested technique. Our results contribute to the development of a clonal propagation protocol for B. vulgaris selected adult plants.
  • Impact of Depression Areas and Land-Use Change in the Soil Organic Carbon and Total Nitrogen contents in a Semi-Arid Karst Ecosystem Silviculture

    Dindaroglu, Turgay; Babur, Emre; Battaglia, Martin; Seleiman, Mahmoud; Uslu, Omer Suha; Roy, Rana

    Resumo em Inglês:

    ABSTRACT Background: Depression areas are essential structural components of Karst ecosystems. Their influence in the carbon and nitrogen dynamics under different land uses, which could be effectively used to define management strategies aiming to combat global warming, however, is not clear. This study investigated the changes in selected soil attributes across four land use types (forest, degraded forest, rangeland and cropland) both in depressed and non-depressed areas in a karst ecosystem in Kahramanmaras, Turkey. Soil attributes investigated in this study included soil pH, soil moisture (SM), soil organic carbon (SOC), total nitrogen content (TN), available water (AW), hydraulic conductivity (HC), root rate (RR) and C/N ratio. Results: Discriminant analyses showed that N, AW, SOC, pH and landuse were the most effective variables affecting the distinction between depression and none-depression areas in karstic ecosystems. According to the structural matrix, the most important single factor affecting the distinction between depression and none-depression areas was SOC, with a correlation coefficient of 0.62. Highest values for SOC, TN and other attributes were found in forest and rangeland land use types, while minimum values were found in cropland land use in most comparisons. Depression areas reduced the negative effects of land use in terms of C, TN, C/N, SM, and RR. Conclusion: As a result, while constructing restoration plans, the study area should be evaluated from a geo-ecological perspective. Ecological capabilities of depression areas should be considered especially in karst environments.
  • Interspecific variations in the habitats of Rhus tripartitum L. populations in Saudi Arabia leading to changes in morphological traits and allelopathic activity Silviculture

    Altamimi, Amal Saleh; Souheila, Naghmouchi

    Resumo em Inglês:

    ABSTRACT Background: The objectives of this study are to (i) determine the variations in the soil composition among six different habitats of six Rhus tripartita populations, (ii) identify and compare the variation in the fruit and seeds parameters of these populations, and (iii) evaluate the differences in Rhus tripartita allelopathic activities among populations on the Chenopodium album weed on it as biological control method. Results: The soils analysis of the six habitats of Rhus tripartita populations revealed a significant variation in the soil variables, while salinity, organic matter, and macro-elements (Cl-, HCO3-, Na+, K+, Ca+ and Mg2+) were the most controlling factor. Rhus tripartita fruits and seeds showed that there is an inter-site variability observed between populations. Morphological study indicating a large-scale diversity among the provenances. It is related to the phenotypic characteristics which may be due to the genetic effect. The Rhus tripartita extract concentration, especially population 4 (P4), showed potential allelopathic activity against Chenopodium album, where the germination was strongly inhibited at a concentration of 10 g l-1. Under same concnetration, seedling root length and shoot lenght were seriously affected. Conclusion: These extracts could be used as green source, eco-friendly bioherbicide and to be integrated into the weed control program of weeds. However, further study is needed for characterization of essential oil of Rhus tripartita and their potential allelopathic activities against the Chenopodium album weed or maybe other weeds, and evaluate its valuable economic use on a large scale.
  • Transpiration of Swartzia tomentifera in response to microclimatic variability in the central Amazon: the net effect of vapor pressure déficit Silviculture

    Antezana-Vera, Saul Alfredo; Marenco, Ricardo Antonio

    Resumo em Inglês:

    ABSTRACT Background: The distribution of precipitation in the Amazon region is changing in last decades, but it is uncertain if transpiration will decrease in response to changes in rainfall distribution. In this study we aimed to assess the effect of climatic variability on whole-tree transpiration (inferred from sap flow measurements). We collected climate data (precipitation, photosynthetically active radiation -PAR, relative humidity, vapor pressure deficit -VPD, and temperature) and measured sap flow rates (SFR) in trees of Swartzia tomentifera. The SFR was measured in the dry season and wet season using the heat ratio method. Results: Sap velocity was positively correlated with PAR and temperature, with partial correlation (rpart) of 0.33 to 0.57 (p < 0.001) during daytime, while at night rpart varied from 0.15 to 0.21 (p < 0.001). When the effects of PAR and temperature were controlled (i.e. after removing the effect of PAR and temperature on sap velocity and VPD), the net effect of VPD on sap velocity became slightly negative (rpart of -0.08 to -0.14, p < 0.01) during daytime. Maximum sap velocities were lower during the dry season (5.9 cm h-1) than in the wet season (9.8 cm h-1, p < 0.001). Conclusion: This study shows that tree transpiration can decrease in the dry season in the central Amazon, associated with an increase in temperature, PAR and vapor pressure deficit. A novelty of this study is to demonstrate that after adjusting for the effect of temperature and PAR, the effect of vapor pressure deficit on sap velocity can become negative. .
  • Pull-out strength of glued-in GFRP rods in timber connections by using of epoxy resin reinforced by nanoparticles Technology Of Forest Products

    Madhoushi, Mehrab

    Resumo em Inglês:

    ABSTRACT Background: In timber structures, connections are the most important and critical section which supply the strength of each structural element. The aim of this study was evaluation the behavior of epoxy resin reinforced by nanoclay (at three levels) on the pull-out strength of glued-in GFRP rods in glulam. For this purpose, two rods with three lengths (50, 150 and 250 mm) and diameters (6.4, 12.7 and 19.1 mm) were inserted at two opposite sides of glulam blocks (with dimension of 8.89 x 8.89 x 29.94 cm) which were glued by epoxy resin. Samples underwent tensile testing and their tensile strength and shear strength were measured. The obtained data were analyzed statistically and the effects of studied factors on bond strength were evaluated. Results: The results showed that the strength of bonding increased with the addition of a low amount of nanoclay, and the length of the rod had a greater effect than its diameter. Furthermore, the amount of nanoclay, rod length and diameter could not significantly affect simultaneously, the performance and strength of glued-in GFRP rods. Conclusion: Nanoclay particle can be considered as a reinforcement for epoxy resin in glued-in GFRP rods and its effect may cause a considerable increase in the mechanical strengths of joints.
  • Changes on structural characteristics of cellulose pulp fiber incubated for different times in anaerobic digestate Technology Of Forest Products

    Tonoli, Gustavo Henrique Denzin; holtman, Kevin; Silva, Luiz Eduardo; Wood, Delilah; Torres, Lennard; Williams, Tina; Oliveira, Juliano Elvis; Fonseca, Alessandra Souza; Klamczynski, Artur; Glenn, Gregory; Orts, William

    Resumo em Inglês:

    ABSTRACT Background: The objective of the present work was to investigate the influence of a pre-treatment of microbial-rich digestate (liquid mesophilic anaerobic digestate - AD-supernatant) on the morphology, crystallinity, and thermal stability of cellulose pulp fiber. Results: The six most abundant bacteria in the AD-supernatant were determined by 16S analysis. The bacteria population was comprised mostly of Bacteroides graminisolvens (66%) and Parabacteroides chartae (28%). Enzymatic activity from the bacteria partially removed the amorphous components and increased the crystallinity and crystallite size of the cellulose substrate. The fiber pulp was incubated in AD-supernatant for 5, 10, and 20 days. The X-ray diffraction data provided evidence that the amorphous portion of the cellulose was more readily and quickly hydrolyzed than the crystalline portion. The longest incubation times (20 days) resulted in substantial deconstruction of the cellulose fiber structure and decreased the thermal degradation temperature. Conclusion: The anaerobic digestate is inexpensive and could be used to effectively aid in the pre-treatment of cellulose on large scale transformation processes, e.g. for making biofuels, cellulose micro/nanofiber production or engineered fiber-based materials.
  • Structural health assessment of a historical building by using in situ stress wave NDT: a case study in Iran Technology Of Forest Products

    Madhoushi, Mehrab; Ebrahimi, Saeideh; Omidvar, Asghar

    Resumo em Inglês:

    ABSTRACT Background: Many historical buildings in Iran need to be protected. In many of these buildings, wood is used as a structural element in features such as beam, pile, roof and floor systems. For this purpose, the architectural features of a historical building located in Gorgan (Northern part of Iran) and characterisation of faults, in addition to identification of wood species were conducted. Stress wave non-destructive testing (NDT) was used and wave speed (WS) was measured in tested members to evaluate the decay situation of major wooden beams of building frames and roof truss. After obtaining data related to WS, time of wave transition (TWT) was calculated and compared with control time. Structural elements were characterized in comparison with control time and classified according to decay severity. Results: The results showed that local hardwood species were used for construction of this building. Furthermore, in some parts of the building, there were severely defected structures, thus highlighting the importance of safety. Moreover, WS strongly depended on the types of faults. Conclusion: Due to high relative humidity of climate, wood structures are exposed to faults in the northern region of Iran. However, their general appearance is adequate and acceptable. For better decision making, the TWT should be accompanied by more investigation into the types of defects.
  • Cellulose nanostructured films from pretreated açaí mesocarp fibers: physical, barrier, and tensile performance Technology Of Forest Products

    Braga, Dayse Gonzaga; Abreu, Juliana Livian Lima de; Silva, Marcela Gomes da; Souza, Tiago Marcolino de; Dias, Matheus Cordazzo; Tonoli, Gustavo Henrique Denzin; Oliveira Neto, Cândido Ferreira de; Claro, Pedro Ivo Cunha; Gomes, Laércio Gouvêa; Bufalino, Lina

    Resumo em Inglês:

    ABSTRACT Background: During de-pulping of açai (Euterpe oleracea) for juice production in the Amazonia, large amounts of fibrous waste are daily discarded, a promising substrate for production of high-value cellulose nanofibrils. Therefore, this study sought to evaluate the modifications of açai surface fibers submitted to chemical pretreatment steps and compare the quality of nanostructured films produced with different cycles of mechanical nanofibrillation. Results: A 2-hour pretreatment (at 5% of NaOH) followed by two NaOH/H2O2 bleaching steps resulted in fibers with increased length and reduced diameter compared to raw fibers while preserving fiber integrity and cellulose I structure. The increase of fibers’ grinding cycles from 3 (minimum to gel point) to 21 (maximum suspension thickness) resulted in nanofibril films with higher crystallinity properties, uniform thickness, compacted morphology, and smoother surface. Nanofibril films formed after different numbers of passages exhibited similar mechanical strength, but distinct barrier properties. Conclusion: Açaí waste films produced with fibers submitted to 3 grinding cycles can be recommended for packaging applications that demand easily dissolving, such as instantaneous food. Oppositely, açaí fibers subjected to 21 cycles in grinder provide films suitable for water-resistant packaging, ideal for secondary coatings of papers and paperboards.
  • An innovative approach on the renewable hybrid barrier: combined use of wood and sand Technology Of Forest Products

    Yumrutaş, Halil İbrahim; Birinci, Emre; Yörür, Hüseyin; Atahan, Ali Osman

    Resumo em Inglês:

    ABSTRACT Background: Wooden materials have been among the basic materials used in many different areas due to some advantages throughout the history. Roadside barriers, which are called passive safety structures, can be produced with different materials such as wood, steel, concrete, and plastic. In this study, Renewable Hybrid Barriers (RHB), a new type of barrier that is used wood in terms of aesthetics, renewability, high shock resistance, and used sand in terms of impact absorption capacity and low cost, produced by taking into account some of the disadvantages of other barrier types. These barriers are planned to be used especially in historical/touristic areas, scenic roads, and in urban areas as urban furniture. Real-time crash tests in accordance with EN 1317 (Road Restraint Systems) standard require high cost and long time. Therefore, the pendulum crash test mechanism frequently used in the literature was manufactured at which the experiments were carried out. Results: The results revealed that the RHBs which has 2 cm thick timber and sand used together, were sufficient and suitable in terms of both cost and necessary safety criteria. It was observed that impregnation and heat treatment applications did not have a considerable negative effect on the performance of RHBs which provide an opportunity to use RHBs for outdoor conditions.. Conclusion: In the light of the results of the study, the optimum wood timber thickness was determined as 2 cm regarding TB 31 test criteria. It is proposed that the crash tests for different wood species, timber thickness, and/or barrier dimensions should carry out in future studies. This study can serve as the basis for the next step, real-time real crash tests. Since the study includes an interdisciplinary subject, it is thought that it will inspire different studies.
  • Factors affecting some properties on surface of thermowood material applied with water-based varnishes modifed with nanoparticles Technology Of Forest Products

    Karamanoğlu, Mehmet; Kesik, Haci İsmail

    Resumo em Inglês:

    ABSTRACT Background: The aim of this study is to determine the surface roughness and adhesion strength of water-based varnishes modified with nanoparticles of zinc oxide (ZnO) and hollow ceramic spherical (HCS) against accelerated UV aging effect in some ThermoWood materials. For this purpose, American ash (Fraxinus americana) and scotch pine (Pinus sylvestris Lipsky) wood were heat treated at a temperature of 190 °C for 1.5 hours and 212 °C for 2 hours. The heat-treated samples were applied with two-component water-based varnishes, with D70 - D99 commercial codes, modified with 1%, 3% and 5% ZnO and HCS nanoparticles individually then these samples were subjected to accelerated aging for 240 hours according to ASTM G154. The surface roughness of varnish layers was determined by TS 6956 EN ISO 4287/A1 and surface adhesion strength by ASTM D4541 principles. Results: The results showed that the nanoparticles generally decreased the surface roughness and adhesion strength in water based varnishes. But surface roughness increased in additives of 5% HCS in D99 and 1% ZnO in D70. Also adhesion strength increased in additives of 5% ZnO and 1% and 5% HCS in D70. Conclusion: The layer properties of water-based varnishes can be improved with ZnO and HCS nanoparticles against aging effects.
  • Oleoresin prospection in Copaifera sp. trees by using impulse tomography Technology Of Forest Products

    Martins, Bianca Cerqueira; Santos, Glaycianne Christinne Vieira dos; Latorraca, João Vicente de Figueiredo

    Resumo em Inglês:

    ABSTRACT Background: Copaiba oil (Copaifera L.) is a raw material used by pharmaceutical, cosmetic, and energy industries. However, the difficulty in locating the oleoresin reservoirs, is an obstacle to its continued supply, affecting the sustainable commercialization of the product. So, the potential of impulse tomography for prospecting oleoresin reservoirs in the trunk of 18 Copaifera sp. trees was tested, in cross-sections at heights levels 0% (DBH), 25%, 50%, 75%, and 100% (1st fork). The impulse tomography prospections (ITP) were performed only at the 0%, in others 12 trees, because of the risk associated with climbing hollow trees. In total 30 trees were tested. Altogether 102 tomograms were analyzed obtaining: average mechanical wave propagation speed (aMPS), minimum mechanical wave propagation speed (minS) and maximum mechanical wave propagation speed (maxS), prospecting height (Hp%) and total tree height (Ht), diameter at the Hp% (Dhp), and low speed mechanical wave propagation percentage areas (LSa%). These variables were analyzed using multivariate analysis. Results: The reservoirs were located exclusively at DBH and confirmed by borer prospection increment in 26.7% of the trees. ITP resulted in 37.3% of correct answers and 62.7% of errors, considering the 99 tomograms. However, it was found that the ITP is efficient to indicate sections for which no significant reservoir or hollow presence is expected to be found. The analysis of the main components showed that, except for Ht, the components are good indicators for the location of the reservoirs. Conclusion: We were able to use tomography to search reservoirs with a significant amount of oleoresin, identify hollow trees, and indicate the exclusion of trees that do not have reservoirs or other alterations.
  • Blended paper: physical, optical, structural, and interfiber bonding analysis Technology Of Forest Products

    Pego, Matheus Felipe Freire; Bianchi, Maria Lúcia

    Resumo em Inglês:

    ABSTRACT Background: Blended paper can present suitable mechanical properties due to sirnergetic effect. However, regarded to physical properties, few studies are conducted. This study aimed to evaluate optical, structural, interfiber bonding, and other physical properties from blended paper and try to understand how these properties can affect applications. The eucalyptus, sisal, and pine pulp were used for handsheet forming. Pulps were disintegrated, refined, and blended two by two in 5/95%, 25/75%, and 45/55% ratios. Also, virgin pulps (100% of each pulp) were used for handsheet forming. Handsheets were formed and evaluated by bond strength, cobb test, air permeance, roughness, optical, Fourier transform infrared spectroscopy (FTIR), and scanning electron microscopy (SEM). Results: Treatments differed statistically in bond strength, cobb test, optical, air permeance, and roughness. Generally, treatments with eucalyptus presented higher bond strength, brightness, and air permeance. Treatments with sisal presented the highest opacity and roughness. Spectra of virgin handsheets presented differences in 2170-2000 and 2360 cm-¹ bands, probably related to residual lignin content. SEM images revealed structural differences between blended and virgin pulps. Conclusion: Treatment T15 (45S 55P) presented the best results, suggesting better physical-mechanical properties. Blended handsheets presented better properties than virgin handsheets on most properties, evidencing a synergetic effect.
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