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Morpho-physiological characteristics in Eucalyptus species can determine N (NUE) and P (PUE) use efficiency and, consequently, the plant's responses to fertilization. The study aimed to evaluate whether morphological and physiological characteristics of seedlings from Eucalyptus species affect the N and P use efficiency. For this, in a greenhouse, Eucalyptus grandis (GPC 23) and Eucalyptus saligna (32864) clones were grown in Hoagland nutrient solution for 21 days, followed by N and P restriction in CaSO4 solution 0.1 mol L−1 during 15 days. Morphological parameters from shoot and root system, dry mass of organs, photosynthetic pigments concentration, and chlorophyll a fluorescence of Eucalyptus species were evaluated, and NUE and PUE were calculated. Eucalyptus grandis presented the highest NUE and PUE values. The highest surface area, volume, and roots length values contributed to these results, justifying the highest dry mass production from leaves, stem, roots, and plant. Eucalyptus saligna presented the lowest NUE and PUE values, which negatively influenced photosynthesis (higher F0 values and lower concentrations of photosynthetic pigments). Root morphological parameters had a strong relationship with NUE and PUE and can be used to select Eucalyptus species, and breeding programs, as they can predict the ability of development of Eucalyptus species under low N and P availability.

Ecological and hydrological impacts are expected when watersheds are under commercial eucalyptus. In this study we evaluated event-based hydrology and sedimentation in paired watersheds under commercial eucalyptus and grasslands cover. Flow, suspended sediment concentration, and sediment production were measured and simulated with the Limburg Soil Erosion Model (LISEM) in paired hydrographic watersheds located in southern Brazil; one occupied with 7-years old Eucalyptus saligna plantation (forest watershed-FW; 0.83 km2) and another Pampa biome with native and exotic grasses used for beef cattle production (grassland watershed-GW; 1.10 km2). The effect of rainfall on hydrological and sedimentological variables was more evident in GW compared with FW. The shape of the hydrograph was steepest in GW, with rapid, marked increase and decrease in flow during rainfall. The parameters changed for model calibration in FW and GW were soil saturated hydraulic conductivity, initial soil moisture, and Manning roughness coefficient, whereby the statistical performance was classified as good (NSE> 0.75). Fourteen events different from those used in the calibration process were validated for FW and GW, with NSE index classified as “good” and “very good” for hydrology. Our study shows limitations of LISEM in calibrating and validating the sediment yield for individual events due to the spatial variability of factors controlling soil erosion. The validated modeling results of this study may be applied in simulating soil and crop scenarios in watersheds cultivated with commercial forest and grassland for grazing.

Considering the increasing need for renewable products, the present work aims to evaluate the physical-chemical properties of the eucalyptus harvest residues and its constituent fractions individually (barks, leaves, and branches), through proximate, ultimate, energetic and thermal analyzes. The biomass studied was Eucalyptus saligna species, cultivated mainly for the production of pulp and paper. The proximate analysis of the residue resulted in the moisture content of 10.1%, ash content of 3.9%, volatile materials about 81.1%, and fixed carbon of 15.0%, showing similar values to the constituent fractions. The ultimate analysis of the residue resulted in 46.5% of carbon content, 5.8% of hydrogen, and 43.2% of oxygen. The high heating value (HHV) for the residue is 17.93 MJ/kg, comparable to other biomasses of importance, including eucalyptus wood, the noblest part of the forest cultivation. The thermogravimetric (TGA) and differential thermal analysis (DTA) were carried out and the resulting thermograms show three main ranges of biomass degradation. The first range, from 30 to 150 °C, corresponds to the drying of the material; in the range from 200 to 325 °C hemicelluloses degrade, with partial degradation of lignin and cellulose, and in the range from 325 to 380 °C, the majority of cellulose degradation takes place. The physical-chemical data demonstrate that the eucalyptus residue is an excellent source of biomass for thermal conversion processes. Obtaining products with higher added value from this residue contributes to the implementation of new technological practices that link economic development to environmental responsibility. Considerando a crescente necessidade de produtos renováveis, o presente trabalho tem como objetivo avaliar as propriedades físico-químicas dos resíduos da colheita do eucalipto e suas frações constituintes individualmente (cascas, folhas e galhos), por meio de análises imediata, elementar, energética e térmica. A biomassa estudada foi a espécie Eucalyptus saligna, cultivada principalmente para a produção de celulose e papel. A análise imediata do resíduo resultou em teor de umidade de 10,1%, teor de cinzas de 3,9%, materiais voláteis em torno de 81,1% e carbono fixo de 15,0%, apresentando valores semelhantes entre as frações constituintes. A análise elementar do resíduo resultou em 46,5% de teor de carbono, 5,8% de hidrogênio e 43,2% de oxigênio. O poder calorífico superior do resíduo foi determinado em 17,93 MJ/kg, comparável a outras biomassas importantes, incluindo a madeira de eucalipto, a parte mais nobre do cultivo florestal. A análise termogravimétrica (TGA) e térmica diferencial (DTA) foram realizadas e os termogramas resultantes mostram três faixas principais de degradação da biomassa. A primeira faixa, de 30 a 150 °C, corresponde à secagem do material; na faixa de 200 a 325 °C as hemiceluloses degradam, com degradação parcial da lignina e celulose, e na faixa de 325 a 380 °C, ocorre a maior parte da degradação da celulose. Os dados físico-químicos demonstram que o resíduo do eucalipto é uma excelente fonte de biomassa para processos de conversão térmica. A obtenção de produtos de maior valor agregado a partir desse resíduo contribui para a implantação de novas práticas tecnológicas que vinculam o desenvolvimento econômico à responsabilidade ambiental.

The carbon market has been attracting attention as an additional source of revenue associated with growing planted forests. In addition to the economic importance, planted forests play an essential role in mitigating climate change due to their high potential to sequester carbon from the atmosphere and store it in soil, biomass or litter. Therefore, forest cultivation and the carbon market present win-win opportunities for both the economic and ecological systems. One question that arises for those who intend to invest in planted forests projects for carbon credits trading is: which species within Pinus or Eucalyptus, performs better in Carbon Sequestration and Storage (CSS)? Based on a systematic review of the scientific literature, we ranked the cultivated species of the genus Eucalyptus and Pinus based on their CSS performance. The findings suggest that Eucalyptus performs slightly better than Pinus, given that this supremacy was reported in 60% of the studies analyzed. However, paired analysis between species show that Pinus patula , P. halepensis, and P. radiata presented better performance than Eucalyptus saligna, E. occidentalis, and E. globulus, respectively. At the same time, Eucalyptus spp., E. cloenziana, E. grandis, and E. tereticornis performed better than Pinus spp., P. armandii, P. massoniana, P. taeda, P. caribaea, and P. roxburghii, respectively. However, species' effective performance in sequestering and storing carbon depends on other issues such as technical factors, management practices, and biophysical conditions. We identified that biophysical conditions, such as the site index, soil type, soil density, stand elevation, water deficit, soil clay, aluminum content, edaphoclimatic conditions and land use change were the most important. Thus, besides the species to be cultivated, the potential for generating carbon credits by planted forests also depends on local biophysical conditions and management practices adopted.

Eucalyptus clones are selected according to productivity, wood quality, rooting capacity, and resistance to drought, frost and diseases. However, kinetic and morphological parameters that determine the absorption efficiency of nutrients such as nitrate (NO3−) and ammonium (NH4+) are often not considered in breeding programs. The objective of this study was to evaluate the morphological, physiological and kinetic parameters of nitrogen uptake by clones of Eucalyptus saligna (32,864) and Eucalyptus grandis (GPC 23). Morphological parameters in shoot and root systems, biomass and N concentrations in different organs, photosynthetic pigment concentrations, parameters of chlorophyll a fluorescence and photosynthetic rates were evaluated. Kinetic parameters, maximum absorption velocity (Vmax), Michaelis–Menten constant (Km), minimum concentration (Cmin) and influx (I) were calculated for NO3− and NH4+ in the two clones. E. grandis clone was more efficient in the uptake of NO3− and NH4+, and showed lower Km and Cmin values, allowing for the absorption of nitrogen at low concentrations due to the high affinity of the absorption sites of clone roots to NO3− and NH4+. Higher root lengths, area and volume helped the E. grandis clone in absorption efficiency and consequently, resulted in higher root and shoot biomass. The E. saligna clone had higher Km and Cmin for NO3− and NH4+, indicating adaptation to environments with higher N availability. The results of NO3− and NH4+ kinetic parameters indicate that they can be used in Eucalyptus clone selection and breeding programs as they can predict the ability of clones to absorb NO3− and NH4+ at different concentrations.

13 páginas.- 7 figuras.- 92 referencias, The mechanisms by which woody plants recover xylem hydraulic capacity after drought stress are not well understood, particularly with regard to the role of embolism refilling. We evaluated the recovery of xylem hydraulic capacity in young Eucalyptus saligna plants exposed to cycles of drought stress and rewatering. Plants were exposed to moderate and severe drought stress treatments, with recovery monitored at time intervals from 24 h to 6 months after rewatering. The percentage loss of xylem vessels due to embolism (PLV) was quantified at each time point using microcomputed tomography with stem water potential (Ψx) and canopy transpiration (Ec) measured before scans. Plants exposed to severe drought stress suffered high levels of embolism (47.38% ± 10.97% PLV) and almost complete canopy loss. No evidence of embolism refilling was observed at 24 h, 1 week, or 3 weeks after rewatering despite rapid recovery in Ψx. Recovery of hydraulic capacity was achieved over a 6-month period by growth of new xylem tissue, with canopy leaf area and Ec recovering over the same period. These findings indicate that E. saligna recovers slowly from severe drought stress, with potential for embolism to persist in the xylem for many months after rainfall events. © 2022 John Wiley & Sons Ltd., This study was supported by an ARC Discovery Project (DP170100761) to BC and TJB and an ARC Future Fellowship (FT130101115) to BC. BM acknowledges support from the ARC Laureate Fellowship FL190100003. CMR‐D was supported by an Individual Fellowship from the European Union's Horizon 2020 research and innovation program under the Marie Skłodowska‐Curie grant agreement no. 751918‐AgroPHYS. JMRP was supported by the ORNL, managed by UT‐Battelle, LLC, for the DOE under contract DE‐AC05‐1008 00OR22725.

Novel species of fungi described in this study include those from various countries as follows: Australia, Chaetomella pseudocircinoseta and Coniella pseudodiospyri on Eucalyptus microcorys leaves, Cladophialophora eucalypti, Teratosphaeria dunnii and Vermiculariopsiella dunnii on Eucalyptus dunnii leaves, Cylindrium grande and Hypsotheca eucalyptorum on Eucalyptus grandis leaves, Elsinoe salignae on Eucalyptus saligna leaves, Marasmius lebeliae on litter of regenerating subtropical rainforest, Phialoseptomonium eucalypti (incl. Phialoseptomonium gen. nov.) on Eucalyptus grandis × camaldulensis leaves, Phlogicylindrium pawpawense on Eucalyptus tereticornis leaves, Phyllosticta longicauda as an endophyte from healthy Eustrephus latifolius leaves, Pseudosydowia eucalyptorum on Eucalyptus sp. leaves, Saitozyma wallum on Banksia aemula leaves, Teratosphaeria henryi on Corymbia henryi leaves. Brazil, Aspergillus bezerrae, Backusella azygospora, Mariannaea terricola and Talaromyces pernambucoensis from soil, Calonectria matogrossensis on Eucalyptus urophylla leaves, Calvatia brasiliensis on soil, Carcinomyces nordestinensis on Bromelia antiacantha leaves, Dendryphiella stromaticola on small branches of an unidentified plant, Nigrospora brasiliensis on Nopalea cochenillifera leaves, Penicillium alagoense as a leaf endophyte on a Miconia sp., Podosordaria nigrobrunnea on dung, Spegazzinia bromeliacearum as a leaf endophyte on Tilandsia catimbauensis, Xylobolus brasiliensis on decaying wood. Bulgaria, Kazachstania molopis from the gut of the beetle Molops piceus. Croatia, Mollisia endocrystallina from a fallen decorticated Picea abies tree trunk. Ecuador, Hygrocybe rodomaculata on soil. Hungary, Alfoldia vorosii (incl.Alfoldia gen. nov.) from Juniperus communis roots, Kiskunsagia ubrizsyi (incl. Kiskunsagia gen. nov.) from Fumana procumbens roots. India, Aureobasidium tremulum as laboratory contaminant, Leucosporidium himalayensis and Naganishia indica from windblown dust on glaciers. Italy, Neodevriesia cycadicola on Cycas sp. leaves, Pseudocercospora pseudomyrticola on Myrtus communis leaves, Ramularia pistaciae on Pistacia lentiscus leaves, Neognomoniopsis quercina (incl. Neognomoniopsis gen. nov.) on Quercus ilex leaves. Japan, Diaporthe fructicola on Passiflora edulis × P. edulis f. flavicarpa fruit, Entoloma nipponicum on leaf litter in a mixed Cryptomeria japonica and Acer spp. forest. Macedonia, Astraeus macedonicus on soil. Malaysia, Fusicladium eucalyptigenum on Eucalyptus sp. twigs, Neoacrodontiella eucalypti (incl. Neoacrodontiella gen. nov.) on Eucalyptus urophylla leaves. Mozambique, Meliola gorongosensis on dead Philenoptera violacea leaflets. Nepal, Coniochaeta dendrobiicola from Dendriobium lognicornu roots. New Zealand, Neodevriesia sexualis and Thozetella neonivea on Archontophoenix cunninghamiana leaves. Norway, Calophoma sandfjordenica from a piece of board on a rocky shoreline, Clavaria parvispora on soil, Didymella finnmarkica from a piece of Pinus sylvestris driftwood. Poland, Sugiyamaella trypani from soil. Portugal, Colletotrichum feijoicola from Acca sellowiana. Russia, Crepidotus tobolensis on Populus tremula debris, Entoloma ekaterinae, Entoloma erhardii and Suillus gastroflavus on soil, Nakazawaea ambrosiae from the galleries of Ips typographus under the bark of Picea abies. Slovenia, Pluteus ludwigii on twigs of broadleaved trees. South Africa, Anungitiomyces stellenboschiensis (incl. Anungitiomyces gen. nov.) and Niesslia stellenboschiana on Eucalyptus sp. leaves, Beltraniella pseudoportoricensis on Podocarpus falcatus leaf litter, Corynespora encephalarti on Encephalartos sp. leaves, Cytospora pavettae on Pavetta revoluta leaves, Helminthosporium erythrinicola on Erythrina humeana leaves, Helminthosporium syzygii on a Syzygium sp. barkcanker, Libertasomyces aloeticus on Aloe sp. leaves, Penicillium lunae from Musa sp. fruit, Phyllosticta lauridiae on Lauridia tetragona leaves, Pseudotruncatella bolusanthi (incl. Pseudotruncatellaceae fam. nov.) and Dactylella bolusanthi on Bolusanthus speciosus leaves. Spain, Apenidiella foetida on submerged plant debris, Inocybe grammatoides on Quercus ilex subsp. ilex forest humus, Ossicaulis salomii on soil, Phialemonium guarroi from soil. Thailand, Pantospora chromolaenae on Chromolaena odorata leaves. Ukraine, Cadophora helianthi from Helianthus annuus stems. USA, Boletus pseudopinophilus on soil under slash pine, Botryotrichum foricae, Penicillium americanum and Penicillium minnesotense from air. Vietnam, Lycoperdon vietnamense on soil. Morphological and culture characteristics are supported by DNA barcodes.

Wood is one of the main materials used in the constructing of covering structures (roofs) because of its versatility. Under this situation, due to solar radiation incidence, the temperature can exceed 60 °C and, such as other environmental conditions, influence the mechanical properties of the wood in use. The aim of this research was to study the influence of exposure time of the wood of four different hardwood species at a temperature of 60 °C on the shear strength parallel to fibers. The wood of the following species was used: Cupiúba (Goupia glabra), Eucalyptus (Eucalyptus saligna), Garapeira (Apuleia leiocarpa), and Jatobá Tamarindo (Hymenaea sp.). In order to investigate the effect of exposure time (0, 168, 456, 720, and 2160 hours) of the wood species in an oven (60 °C) on the values of shear strength in the direction parallel to fibers, an analysis of variance (ANOVA) was carried out at 5% significance level. According to the results, the time the wood was exposed to the operating temperature significantly influenced the shear strength in the direction parallel to fibers. In addition, all species showed a decrease in shear strength after 456 hours of exposure at a constant temperature of 60 °C.

Reforestation wood is interesting for construction, due to its potential as material source for manufacturing. For this purpose, the Eucalyptus genus has resulted in a better characterization of the material properties. During the production process, wood is machined at some stage, which influences the wood gluing quality. This study considered the performance of Eucalyptus saligna wood joints bonded with four commercial polyvinyl-acetate-based resins with different physical characteristics and chemical compositions. The surfaces of samples were prepared and machined by an up-milling process, using a planer, with wood feed rates of 6 m/min, 11 m/min, 16 m/min, and 21 m/min, which had advances per tooth of 0.25 mm, 0.45 mm, 0.66 mm, and 0.87 mm, respectively. The samples were prepared for shear strength testing of the glue line. During the preparation, all pieces were randomly bonded with regards to the formation plans of wood growth rings. Shear strength values were statistically compared to analysis of variance and Tukey test. Only C4 adhesive reached good results at all feed rates as well as having the best shear strength compared to other resins. Commercial adhesives had distinct interactions on the adhesive-wood interface, which resulted in different adhesion strengths.

Eucalyptus, the most widely planted tree genus worldwide, is frequently cultivated in soils with low water and nutrient availability. Sodium (Na) can substitute some physiological functions of potassium (K), directly influencing plants’ water status. However, the extent to which K can be replaced by Na in drought conditions remains poorly understood. A greenhouse experiment was conducted with three Eucalyptus genotypes under two water conditions (well-watered and water-stressed) and five combination rates of K and Na, representing substitutions of 0/100, 25/75, 50/50, 75/25, and 100/0 (percentage of Na/percentage of K), to investigate growth and photosynthesis-related parameters. This study focused on the positive effects of Na supply since, depending on the levels applied, the Na supply may induce plants to salinity stress (>100 mM of NaCl). Plants supplied with low to intermediate K replacement by Na reduced the critical level of K without showing symptoms of K deficiency and provided higher total dry matter (TDM) than those Eucalyptus seedlings supplied only with K in both water conditions. Those plants supplied with low to intermediate K replacement by Na had improved CO2 assimilation (A), stomatal density (Std), K use efficiency (UEK), and water use efficiency (WUE), in addition to reduced leaf water potential (Ψw) and maintenance of leaf turgidity, with the stomata partially closed, indicated by the higher values of leaf carbon isotope composition (δ13C‰). Meanwhile, combination rates higher than 50% of K replacement by Na led to K-deficient plants, characterized by the lower values of TDM, δ13C‰, WUE, and leaf K concentration and higher leaf Na concentration. There was positive evidence of partial replacement of K by Na in Eucalyptus seedlings; meanwhile, the ideal percentage of substitution increased according to the drought tolerance of the species (Eucalyptus saligna < Eucalyptus urophylla < Eucalyptus camaldulensis).

O objetivo deste trabalho foi avaliar o potencial das madeiras de Eucalyptus benthamii, Eucalyptus dunnii, Eucalyptus grandis, Eucalyptus saligna e Eucalyptus urophylla, para produção de painéis colados lateralmente (EGP) e madeira laminada colada (MLC). As propriedades físicas e químicas das madeiras foram determinadas com base nas normas COPANT 461/459:1972 e TAPPI 204/252:2002. Foram confeccionadas juntas coladas com adesivo acetato de polivinila (PVA), com gramaturas de 150 g m-2 e 200 g m-2, e resorcina-formaldeído (RF), com 200 g m-2 e 300 g m-2. A qualidade de colagem foi avaliada por meio de ensaios de cisalhamento, com base na norma EN 13354:2008. Todas as espécies apresentaram densidade básica de média a baixa e anisotropia de contração de média a alta. O teor de extrativos totais e pH estão dentro da faixa referenciada na literatura. As avaliações dos resultados com base nos requisitos da norma EN 15353:2008 para 5º percentil inferior indicaram que as espécies E. benthamii, E. dunnii, E. grandis e E. saligna, apresentam potencial para produção de painéis EGP com adesivo PVA, para o uso interno, e externo com cobertura. Para a colagem com adesivo RF, o E. dunni apresentou melhores resultados, sendo indicativo do seu bom potencial para a produção de madeira laminada colada, visando aplicações estruturais em ambientes interno úmido e externo. Para os dois tipos de adesivos o aumento na gramatura não afetou os resultados de cisalhamento das juntas coladas.

This evaluated the natural resistance of wood from seven Eucalyptus trees in field decay and soil bed tests. Two 12-year-old trees were randomly sampled per species, with 2,2 m logs being obtained from the basal section of each tree. The samples were taken in two positions in the radial direction of the stem (middle heartwood and transition zone; containing heartwood and sapwood). The field decay tests were installed in three municipalities in the southern state of Espírito Santo, and the soil utilized soil from the three field decay test areas. The field decay tests were evaluated after six, 12 and 18 months after installation and the soil bed tests after six months. The Scott-Knott test (p ≤ 0,05) was used in the analysis and evaluation of the tests. The sapwood-heartwood (transition region) exhibited the greatest mass losses for the field decay and soil bed tests. On average, for the soil bed test the lowest mass losses were observed for the soil of Vargem Alta (5,00 %), with greater mass losses observed for São José do Calçado (7,05 %) and Jerônimo Monteiro (9,90 %). In the field decay test the organisms present in the soil of São José do Calçado and related to the organic matter content Eucalyptus grandis and Eucalyptus saligna more intensely.

The objective of this study was to evaluate the production costs of processing logs from Eucalyptus grandis Hill ex Maiden and Eucalyptus saligna Sm, using two sawing pattern in a medium-sized sawmill. Alternating tangential sawing pattern was used for logs with a mean diameter of 33.0 cm and the radial sawing pattern for logs with a mean diameter of 47.0 cm. Based on the data obtained in the different sawing pattern, the fixed, variable and total costs were calculated and, subsequently, the average value for each of these costs. For the alternating tangential sawing pattern, the fixed cost represented 19.32% and the variable cost 80.68%. For the radial sawing pattern, the fixed cost represented 18.92% and the variable cost 81.08%. The radial sawing pattern presented lower average production costs, with a difference of 22.89 R$/m³, however there is no significant difference between the sawing pattern.

Copper damages plants when present in high concentrations in the soil. This study assessed the growth and tolerance of Eucalyptus grandis, E. saligna, E. dunnii, and Corymbia citriodora seedlings in soil contaminated by copper. The experimental design was completely randomized in a factorial scheme (4 × 6), with four eucalyptus species and six copper doses (0, 80, 160, 240, 320, 400 mg kg-1) with eight replications. The experiment was performed in a greenhouse for 120 days. The height, stem diameter, root dry mass and shoot dry mass, root specific surface area, Dickson quality index, and tolerance index were assessed. The results showed that the morphological parameters of the studied eucalyptus species were reduced by the copper doses added in the soil. However, the Corymbia citriodora and the Eucalyptus saligna species had a higher tolerance index to the metal.

We aimed to evaluate the bioherbicide potential of Eucalyptus saligna leaf litter essential oil, its fractions and major compounds. Six essential oil fractions were obtained by preparative thin-layer chromatography and analyzed by gas chromatography/mass spectrometry. Effects of the oil, its fractions and major compounds (1,8-cineole and/or α-pinene) diluted in aqueous solution were assessed on germination and seedling growth. Recipient species were Lactuca sativa (model), Amaranthus viridis (weed), Eragrostis plana (weed), and Paspalum notatum (forage). The essential oil was more phytotoxic on A. viridis and L. sativa, followed by E. plana, and caused no effects on P. notatum. Amaranthus viridis was inhibited by all treatments, mainly the essential oil, α-pinene and fraction 6, whereas E. plana was more affected by the oil fractions. Results revealed the species-specific phytotoxic effects of E. saligna essential oil, indicating its potential use for controlling A. viridis and E. plana. Phytotoxic effects of essential oils or their components should not be generalized, as effects may change according to recipient species.

BackgroundSpecies of the generaEucalyptus,Cupressus, andPinusare the most widely planted tree species in the country in general and in Chilimo dry Afromontane forest in particular. Eucalyptus covers 90% of the total planted forest area in the country. However, only limited information exists in the country regarding aboveground biomass (AGB), belowground biomass (BGB), growth, and yield. This study was conducted to assess the variables on 25 and 30 years of age for three planted species:Cupressus lusitanica,Eucalyptus saligna, andPinus patulain Chilimo plantation forest, in the Central Highlands of Ethiopia. A two-times inventory was conducted in 2012 and 2017. A total of nine square sampled plots of 400 m2each, three plots underCupressus lusitanica, 3Eucalyptus saligna, and 3Pinus patulawere used for data collection. Data on height, diameter, soil, and tree stumps were collected. Percent C, % N, and bulk density was performed following chemical procedure.ResultsThe aboveground biomass ranged from 125.76 to 228.67 t C ha−1and the basal area and number of stems from 3.76 to 25.50 m2 ha−1and 483 to 1175 N ha−1, respectively. The mean annual basal area and volume increment were between 0.97 and 1.20 m2 ha−1 year−1and 10.79 and 16.22 m3 ha−1 year−1. Both carbon and nitrogen stock of the planted forest was non-significant among the tree species.ConclusionThe aboveground biomass, growth, and yield significantly varied among the species.Cupressus lusitanicahad the highest aboveground biomass, volume, and basal area, whileEucalyptus salignahad the lowest value .To a depth of 1 m, total carbon stored ranged from 130.13 to 234.26 t C ha−1. The total annual carbon sequestration potential was 12,575.18 t CO2eq.Eucalyptus has the highest carbon stock density and growth rate than other species.

The management of eucalyptus harvest residues can affect the initial growth and nutrient content of new eucalyptus plantations. We investigated the initial growth and nutritional status of Eucalyptus saligna plantation according to five alternative strategies for management of harvest residues on sandy soil, in the municipality of Barra do Ribeiro, RS. The total height, diameter at breast height (DBH), individual volume and nutrient content in the leaves were evaluated after twelve months. We observed that the maintenance of harvest residues increased growth in height, DBH and individual volume. The levels of calcium in leaves of eucalyptus were higher in the treatments in which harvest residues were removed, whereas the opposite was confirmed for sulfur. The differences found in our study point that the maintenance of harvest residues increase the eucalyptus growth, especially in sandy soils.

Climate change is currently part of the agenda in scientific debates and of interest in forest sciences, but studies of vulnerability of cultivated forest species to climate change are rare. The objective of this study was to simulate the duration of the seedling phase in two eucalyptus species ( Eucalyptus saligna and Eucalyptus grandis) in elevated temperature scenarios at Santa Maria, RS, Brazil, considering several emergences dates. The seedling phase was considered from the emergence of the seedlings until the appearance of the 25 th leaf on the main stem. Leaf appearance rate (LAR) was estimated using a multiplicative model with a non-linear response function of LAR to daily mean air temperature, with coefficients for the species Eucalyptus saligna and Eucalyptus grandis. Twelve emergence dates (day 15 of each month of the year) and six climate scenarios (current, +1°C, +2°C, +3°C, +4°C, and +5°C) were considered. The Climate scenarios are made up of synthetic series with one hundred years of daily minimum and maximum air temperature synthetic series. The LAR model was run in each year of the climate scenarios for each emergence date and species, and the number of days from emergence to the appearance of the 25 th leaf was counted (seedling phase duration). Statistical analysis consisted of analysis of variance for the variable duration of the seedling phase, assuming a three-factor experiment (Factor A= six climates scenarios, Factor B= twelve emergence dates, Factor C= two species) in a completely randomized design, with each year of simulation as a replication. The results indicated a reduction of the seedling phase duration in the warm climate scenarios for emergences from March to September, and a increase in the duration for emergences from October to February and on an annual basis, the increase in temperature leads to a decrease in time of seedling in a nursery and thus increases the annual seedling production of Eucaliptus. However, low seedling vigor and disease related problems may increase, mainly during summer. Benefits and disadvantages of these results should be considered in policies for mitigating the effects of global warming in silviculture.

A associação ectomicorrízica beneficia as plantas ao proporcionar aumento na área de absorção radicular obtendo mais nutrientes e água, podendo possibilitar o crescimento do hospedeiro em solos submetido a condições adversas. O objetivo deste trabalho foi avaliar o efeito de diferentes isolados ectomicorrízicos no crescimento das mudas de Eucalyptus grandis W. Hill ex Maid., Corymbia citriodora (Hook.) K.D. Hill & L.A.S. Johnson, Eucalyptus saligna Sm. e Eucalyptus dunnii Maiden. O delineamento foi inteiramente casualizado em arranjo fatorial 4 x 4, sendo quatro espécies de eucalipto (Eucalyptus grandis, Corymbia citriodora, Eucalyptus saligna e Eucalyptus dunnii) e quatro isolados de inóculos ectomicorrízicos (UFSC-Pt116 (Pisolithus microcarpus (Cooke & Massee) Cunn), UFSC-132 (Pisolithus tinctorius (Pers.) Coker & Couch), UFSC-121, e sem inoculação), com 12 repetições. Após três meses de condução do experimento foram avaliados: percentual de colonização ectomicorrízica, altura de planta; diâmetro do colo; número de folhas; massa seca da parte aérea e radicular. Também foram calculadas as relações: massa seca aérea/massa seca radicular, altura/diâmetro do colo e o índice de qualidade de Dickson. A altura de planta, número de folhas e a massa seca aérea apresentaram médias superiores nas espécies Eucalyptus dunnii e Corymbia citriodora, quando na inoculação com UFSC-132. A inoculação com UFSC-Pt116 resultou em 63,3% de raízes colonizadas em Corymbia citriodora, enquanto Eucalyptus dunnii inoculado com UFSC-121 teve 67,7% de suas raízes colonizadas. O isolado ectomicorrízico UFSC-132 proporciona maior crescimento de mudas de Eucalyptus dunnii e Corymbia citriodora em relação à testemunha sem inoculação.

Background: In Southern Brazil, large areas of grassland have been replaced by Eucalyptus plantations. Vegetation is scarce under plantations which may be associated with Eucalyptus releasing of al...

We studied the interaction between Eucalyptus saligna woodlots and maize crop in southern Rwanda. Three sites were selected and in each, a eucalypt woodlot with mature trees and a suitable adjoining crop field of 12.75 m × 30 m was selected. This was split into two plots of 6 m × 12 m and further subdivided into nine sub-plots running parallel to the tree-crop interface. Maize was grown in both 6 m × 12 m plots and one of these received fertiliser. Soil moisture, nutrients and solar radiation were significantly reduced near the woodlots, diminishing grain yield by 80% in the 10.5 m crop-field strip next to the woodlot. This reduction however affects only 10.5% of the maize crop field, leaving 89.5% unaffected. Spreading the loss to a hectare crop field, leads to an actual yield loss of 0.21 t ha−1, equivalent to 8.4%. Expressing yield loss in tree-crop systems usually presented as a percentage of yield recorded near the trees to that obtained in open areas may be misleading. Actual yields should be reported with corresponding crop field areas affected. Variation in grain yield coincided with those for soil moisture, soil N and K; all increasing from the woodlot-maize interface up to 10.5 m and remaining similar to the values in open areas thereafter. Solar radiation continued to increase with distance up to 18 m from the woodlot-maize interface. Harvest index in unfertilised maize exceeded that in the fertilised treatment reflecting the crop’s strategy to allocate resources to grain production under unfavourable conditions. Fertilisation increased maize yield from 1.3–2.6 t ha−1 but the trend in the woodlot effects on maize remained unaltered.

Eucalyptus is the second major wood species used for Tunisian reforestation since 1957, and they are found around the country in several arboretums. Eucalyptus may be an interesting raw material to the Tunisian wood industry. The main obstacle to its industrial exploitation is its natural propensity to incur internal checking, collapse and a high transverse shrinkage during industrial drying process. This study focused on the physical and mechanical properties of reforested Eucalytus saligna and Eucalyptus camaldulensis from the north west of Tunisia. Moisture content, densities, shrinkages and mechanical properties were determined. Then, the impact of pre-steaming on the physical properties of modified wood was investigated. The results showed that both Eucalyptus possess low dimensional stability and mechanical properties compared to other Eucalyptusspecies from Tunisia, Morocco, Australia and Brazil. These wood characteristics were mainly due to their low density and sensitivity to collapse reactions, occurred during drying. Pre-steaming process reduced Eucalyptswood moisture content, changing the wood permeability and resulting in a residual collapse recovery and a decrease in wood shrinkage. Pre-steaming treated E. camaldulensis and E. saligna wood could be valuable as furniture and/or structural material without being submitted to moisture content variation.

Background and Objectives. Water stress is a major constraining factor of Eucalyptus plantations&rsquo, growth. Within a genetic improvement program, the selection of genotypes that improve drought resistance would help to improve productivity and to expand plantations. Leaf characteristics, among others, are important factors to consider when evaluating drought resistance evaluation, as well as the clone&rsquo, s ability to modify leaf properties (e.g., stomatal density (d) and size, relative water content at the time of stomatal closure (RWCc), cuticular transpiration (Ec), specific leaf area (SLA)) according to growing conditions. Therefore, this study aimed at analyzing these properties in nursery plants of nine high-productivity Eucalyptus clones. Material and Methods: Five Eucalyptus globulus Labill. clones and four hybrids clones (Eucalyptus urophylla S.T. Blake Eucalyptus grandis W. Hill ex Maiden, 12&euro, Eucalyptus urograndis &times, E. globulus, HE, Eucalyptus dunnii Maiden&ndash, E. grandis E. globulus, HG, Eucalyptus saligna Sm. &times, Eucalyptus maidenii F. Muell., HI) were studied. Several parameters relating to the aforementioned leaf traits were evaluated for 2.5 years. Results: Significant differences in stomatal d and size, RWCc, Ec, and SLA among clones (p &lt, 0.001) and according to the dates (p &lt, 0.001) were obtained. Each clone varied seasonally the characteristics of its new developing leaves to acclimatize to the growth conditions. The pore opening surface potential (i.e., the stomatal d &times, size) did not affect transpiration rates with full open stomata, so the water transpired under these conditions might depend on other leaf factors. The clones HE, HG, and 12&euro, were the ones that differed the most from the drought resistant E. globulus control clone (C14). Those three clones showed lower leaf epidermis impermeability (HE, HG, 12&euro, ), higher SLA (12&euro, HG), and lower stomatal control under moderate water stress (HE, HG) not being, therefore, good candidates to be selected for drought resistance, at least for these measured traits. Conclusions: These parameters can be incorporated into genetic selection and breeding programs, especially Ec, SLA, RWCc, and stomatal control under moderate water stress.

This study assessed the moulding, drilling, turning, sanding, and routing properties of seven plantation-grown hardwood species from southeast Australia to evaluate their potential as a resource for the manufacture of high quality furniture and furnishings. Eucalyptus grandis, Eucalyptus saligna, Corymbia maculata, Eucalyptus camaldulensis, Eucalyptus sideroxylon, Eucalyptus cladocalyx, and Eucalyptus globulus were machined using different tools, and the surface quality obtained was visually graded. A sanding sequence of 100-150 grit produced satisfactory surfaces for furniture manufacturing for most studied species. Usually, a feeding direction against the rotational direction of the tool showed best results and reduced incidence of corner breakout when routing. Overall, high-density plantation-grown Australian hardwood species performed well during machining trials with the use of appropriate parameters and cutting tools allowing overcoming some typical processing difficulties for some species. The data obtained within this study will allow optimising the machining process of plantation-grown wood in Australia and increase value from the current plantation resource.