Wounding and exogenous auxin are needed to induce adventitious roots in Chestnut microshoots. However, the specific inductive role of wounding has not been characterized in this species. In the present work two main goals were established: First, we prompted to optimize exogenous auxin treatments to improve overall health status of the shoots at the end of the rooting cycle. Second, we developed a time-series transcriptomic analysis to compare gene expression in response to wounding alone and wounding plus auxin, focusing in the early events within the first days after treatments. Results suggest that the expression of many genes involved in the rooting process is under direct or indirect control of both stimuli. However, specific levels of expression of relevant genes are only attained when both treatments are applied simultaneously, leading to the successful development of roots. In this sense, we have identified four transcription factors upregulated by auxin (CsLBD16, CsERF113, Cs22D, CsIAA6), with some of them being also induced by wounding. The highest expression levels of these genes occurred when wounding and auxin treatments were applied simultaneously, correlating with the rooting response of the shoots. Results in this work clarify the genetic nature of the wounding response in chestnut, its relation to adventitious rooting and might be helpful in the development of more specific protocols for the vegetative propagation of this species.

Jujube (Ziziphus jujuba Mill.) stands as a pivotal fruit tree with significant economic, ecological, and social value. Recent years have witnessed remarkable strides in multi-omics-based biological re-search on jujube. This review began by summarizing advancements in jujube genomics. Subse-quently, we provided a comprehensive overview of the integrated application of genomics, tran-scriptomics, and metabolomics to explore pivotal genes governing jujube domestication traits, quality attributes (including sugar synthesis, terpenoids, and flavonoids), and responses to abiotic stress, and discussed the transcriptional regulatory mechanisms underlying these traits. Further-more, challenges in multi-omics research on jujube biological traits were outlined, and we pro-posed the integration of resources such as pan-genomics and sRNAome to unearth key molecules and regulatory networks influencing diverse biological traits. Incorporating these molecules into practical breeding strategies, including gene editing, transgenic approaches, and progressive breeding, holds the potential for achieving molecular-design breeding and efficient genetic en-hancement of jujube.

The study sheds light on the impact of urbanization on fragile ecosystems such as the western Himalayas. We use Haldwani in Uttarakhand as an example of human encroachment and loss of ecosystem services. Several environmental parameters such as Nighttime light (NTL), Land Surface Temperatures (LSTs), Aerosol Optical Depth (AOD) and forest cover are used based on satellite imagery to allow a bidecadal comparison (between 2000 and 2020) of the status of these parameters for the city based on these parameters shows a decline in ecosystem services. Significant statistical differences for LSTs and AOD (p < 0.001) can be found in the bidecadal comparison. Furthermore, a strong negative correlation was found between LST-NDVI (r = -0.69) and between NTL-NDVI (r = -0.58) in earlier and last decade intervals. In addition, long-term multi-spectral satellite imagery also shows a decline in tree cover in the reserved forest. Therefore, focusing on ecosystem services related to tree cover in reserved forest areas, particularly in the Indian Himalayan Region (IHR) must be part of a broader action plan to address these issues to further protect fragile Himalayan ecosystems.

The European white birch, scientifically known as Betula pendula, and its variant, B. pendula 'Dalecarlica' are characterized by a serrated leaf margin that enhances their aesthetic appeal. However, the lobed leaf trait can undergo random and spontaneous reversion to the typical ovoid or cordate shape during asexual reproduction. Investigating and elucidating the molecular mechanisms underlying this unpredictable reversion mutation is essential for comprehending the birch leaf development process. In this research, we employed a non-lobed-leaf mutant derived from a lobed-leaf birch clone during plant tissue culture. We adopted a multi-omics approach, including whole-genome resequencing, transcriptome sequencing, and methylation profiling, to analyze and compare genomic variations and gene expression modifications. The study revealed that the 24 variant genes affected by 1464 SNP/InDel sites in the genome of the non-lobed-leaf mutant are not associated with leaf development. While the overall methylation level in the mutant's genome closely resembles that of the serrated-leaf birch, ten genes exhibit differential methylation accompanied by differential expression. Transcriptome sequencing demonstrated that the differentially downregulated genes in the mutant are significantly enriched in the GO:0009733 (response to auxin) and GO:0009734 (auxin-activated signaling) pathways. Validation through McrBC-PCR and qRT-PCR confirmed differential methylation and expression of BpIAA9 in the reversion mutant. The elevated methylation level in the BpIAA9 promoter leads to reduced expression, resulting in changes in the expression of auxin-responsive genes. This, in turn, leads to a transcriptional downregulation enrichment effect in auxin-related pathways in the reversion mutant, ultimately inhibiting the regulation of leaf veins by auxin during their development.

Shrubland and forestland covers are highly prone to fire. The Normalized Difference Vegetation Index (NDVI) has been widely used for biomass quantitative assessment. This study aims were the following: (1) to compute the NDVI annual curve for two types of land cover eucalypts and shrubland areas; (2) to collect field data in these two types of land cover to estimate aboveground biomass (AGB); and (3) to produce AGB maps for eucalypts and shrubland areas by modelling AGB with NDVI and validate them with other data sources. A study area in the central inland Portugal was considered. The Sentinel-2 MSI imagery for the year of 2022 and 2023 were used to compute the NDVI. The NDVI annual curve for 2022 showed a minimum observed between July and August, in accordance with the climatological data, and allowed differentiating eucalypts from shrubland areas. Spectral signatures also confirmed this differentiation. The fitted linear models for AGB prediction using the NDVI imagery showed good fitting performances (R2 of 0.76 and 0.69). The AGB maps provide a relevant decision support tool for forest management and for fire hazard and fire severity mitigation. Further research is needed using more robust data sets for models’ independent validation.

Nitrogen (N) is an important mineral nutrient for plant growth, as well as a limiting factor for crop yield, and how to improve the utilization efficiency of N fertilizer by plants is currently a research hotspot. This article uses bioinformatics methods to identify and analyze members of the glutamine synthetase (GS) and glutamate synthase (GOGAT) gene families in pecan. A total of 6 GS genes and 4 GOGAT genes were identified, and their physicochemical properties, gene structures, and homologous evolutionary relationships were analyzed. Analysis of tissue-specific expression of GS and GOGAT genes based on transcriptome data from pecan. The enzyme activities of GS and GOGAT and the gene expression were quantitatively analyzed under different N form ratios in pecan. According to the results, the promoter cis-acting elements of GS and GOGAT genes can be roughly divided into three types: light-responsive elements, hormone-responsive elements, and stress-responsive elements. The results of homologous evolution showed that there was no tandem duplication event for the two gene families, and GS and GOGAT have undergone purification during the evolutionary process. CiGS2s and CiFd-GOGATs were expressed mainly in leaves, and CiNADH-GOGATs were expressed mainly in fruits. The qPCR analysis results showed that T4 treatment significantly increased the expression levels of CiGS and CiGOGAT genes in the leaves. The enzyme activities of GS and GOGAT in pecan were significantly increased under T3, T4, and T5 treatments. In summary, a higher proportion of ammonium nitrogen (NH4+) in the nutrient solution was profit to pecan NH4+ assimilation. This study determined the appropriate nitrogen ratio for pecan, promoting a theoretical basis for reducing environmental pollution caused by nitrogen fertilizer and improving the nitrogen utilization efficiency of pecan. In summary, both CiGSs and CiGOGATs exhibit tissue specificity, and an ammonium-nitrate mixture with a higher proportion of NH4+ is more favorable for NH4+ assimilation in pecan. This study provides a reference basis for further understanding the functions of CiGSs and CiGOGATs in pecan, and offers a theoretical foundation for improving N use efficiency in pecan.

The functioning of forest ecosystems depends on the taxonomic and ecological diversity of soil fungi. Urbanization is increasing worldwide and is regarded a major driver of environmental change altering local species assemblages in urban forest. We investigated whether the degree of urbanization and local forest characteristics affect the soil fungal community in 20 beech forests located along a rural–urban gradient in the city of Basel and its suburbs (Switzerland). We analyzed their soil fungal communities by DNA metabarcoding of the rDNA ITS2 region and related these data to local forest vegetation characteristics and soil properties. The number of fungal OTUs in the 20 forests examined ranged from 170 to 303. Richness, diversity and evenness of fungal OTUs were all significantly affected by the degree of urbanization, but in different ways. OTU richness was highest in forests in areas with a low degree of urbanization and lowest in forests in rural areas. In contrast, the diversity of OTUs increased with increasing degree of urbanization. Different fungal phyla and fungal guilds showed distinct patterns in their relative abundance along the rural-urban gradient. The degree of urbanization reduced the relative abundance of symbiotrophic fungi, but increased that of saprotrophic and pathotrophic fungi. Our results show that urbanization alters soil fungal community, which in turn can lead to changes in forest ecosystems.

Transcription of glycine-rich RNA-binding protein 2 (PeGRP2) transiently increased in root and shoot of Populus euphratica (salt-resistant poplar) upon initial salt exposure and tended to decrease after long-term NaCl stress (100 mM, 12 days). PeGRP2 overexpression in the hybrid Populus tremula × P. alba ‘717-1B4’ (P. × canescens) increased salt sensitivity, which was reflected in plant growth and photosynthesis. PeGRP2 contains a conserved RNA recognition motif domain at the N-terminus, and RNA affinity purification (RAP) sequencing was developed to enrich target mRNAs that physically interact with PeGRP2 in P. × canescens. RAP sequencing combined with RT-qPCR revealed that NaCl decreased the transcripts of PeGRP2-interacting mRNAs encoding photosynthetic proteins, antioxidative enzymes, ATPases, and Na+/H+ antiporters in transgenic poplar. Particularly, PeGRP2 negatively affected the stability of target mRNAs encoding photosynthetic proteins (PETC and RBCMT), antioxidant enzymes (SOD[Mn], CDSP32 and CYB1-2), ATPases (AHA11, ACA8 and ACA9), and Na+/H+ antiporter (NHA1). This resulted in (i) a greater reduction in Fv/Fm, YII, ETR and Pn, (ii) a less pronounced salt activation of antioxidative enzymes, and (iii) a reduced ability to maintain Na+ homeostasis in transgenic poplars during long-term salt stress, leading to a lowered ability to tolerate salinity stress.

Parkland contributes economic, social, and ecological benefits worldwide. However, parklands degradation is an encounter to biodiversity loss needs generating information on woody species. This study was aimed to investigate woody species composition, diversity, structure, and management of parklands along Agroecology, and farmers’ wealth status. Multistage sampling technique was employed. Highland Bede Kebele, and midland Durgi Kebele were randomly selected. A total of 60 quadrats with size of 100m x 50m were used for inventory. A total of 276 respondents were used. Species richness, Shannon, Simpson, and evenness diversity indices were subjected to one-way ANOVA, and independent t-test for comparison STATA V. 17.0. Of 31 woody species, (16 families in 26 genera) observed, 26 woody species belonging to 13 families in 22 genera from midland while 18 woody species belonging to 12 families in 16 genera from highland parklands were observed. Species richness 6.8, 3.7; Shannon 1.82, 1.68; Simpson 0.85, 0.73; evenness 0.83, 0.7 were observed in midland, and highland parklands, respectively. Poorly regenerated stands were observed along Agroecology. Pruning, pollarding, coppicing, lopping, cutting, fertilizing, watering were common management practices. In conclusion, woody species diversity, and structure were affected by Agroecology, and socioeconomic factors needing intervention to enhancing woody species conservation.

The globose scale (GS) (Sphaerolecanium prunastri Boyer de Fonscolombe) is a sucking insect that feeds on saps of wild apricot tree (Prunus armeniaca L.) in the Xinjiang Uygur Autonomous Region of northwestern China. It feeds on branches of wild apricot leading to poor growth, leaf yellowing and leaf drop, and sometimes mortality. Since the initial infestation in 2018, all the main valleys of wild apricot trees have been affected, but there is little research on the host’s physiological response to GS infestation. We measured the differences in growth between infested and non-infested wild apricots. The results showed that the diameter of shoot branches, the fresh weight, dry weight, length, width, area, and chlorophyll content of leaves, and the longitudinal diameter of fruit, were all significantly less for infested wild apricot trees than for un-infested wild apricot. The branch length of shoots, cross diameter, and weight of fruit also decreased, although the differences were not significant. Overall, GS infestation significantly reduced the growth of wild apricot trees, and may accelerate the damage by GS to wild apricot over time.

The impact of drought stress on plant growth in arid regions is a critical concern, necessitating the exploration of strategies to enhance plant drought resistance, particularly during the early stages of drought stress. This study focuses on the ectomycorrhizal fungus Cenococcum geophilum, renowned for its extensive genetic diversity and broad host compatibility, making it a crucial ally for host plants facing external stresses. We utilized approximately 5-month-old Pinus massoniana seedlings inoculated with different ecotypic strains of C. geophilum for 7 days of drought stress. The results showed that the inoculation of most strains of C. geophilum enhanced the drought resistance of P. massoniana seedlings under the early stages of drought stress, by influencing the water content, photosynthesis, accumulation of osmotic adjustment substances, and antioxidant enzyme activities in both shoots and roots of seedlings. These responses were further validated through transcriptome analysis. Notably, the level of drought resistance observed in mycorrhizal seedlings was irrespective of the level of drought tolerance of C. geophilum strains. This study contributes essential data for understanding the drought response mechanisms of mycorrhizal P. massoniana seedlings inoculated by distinct C. geophilum ecotypes, and guidance on selecting candidate species of ectomycorrhizal fungi for mycorrhizal afforestation in drought areas.

In regenerated oak forests, weeds are present throughout the year, the ones appearing in early spring representing a major problem. Hence, the aim of this study was to examine herbicides for early spring broadleaved weed control in the regenerated oak forests while the seedlings are in a dormant stage. During 2019 and 2020 two experiments were set up in regenerated pedunculate oak forests with 2-yar and 3-year-old seedlings and two herbicides were applied in two doses: fluroxypyr at dose 360 g a.i. ha-1 and 540 g a.i. ha-1 and clopyralid at dose 100 g a.i. ha-1 and 120 g a.i. ha-1. The results from the two-year investigations showed that fluroxypyr and clopyralid significantly reduced early spring broadleaved weeds in the regenerated pedunculate oak forests but both doses of fluroxypyr provided greater control of presented weeds than the applied doses of clopyralid. The manual weeding reduced broadleaved weeds in experiments, but that method did not have a long-term effect on the reduction of weeds. Applied doses of herbicides fluroxypyr and clopyralid did not cause phytotoxicity symptoms in dormant oak seedlings. All investigated treatments significantly reduced fresh broadleaved weed biomass compared to the control. Generally, it can be concluded that fluroxypyr and clopyralid can be successfully used for control of many early spring broadleaved weeds in the regenerated pedunculate oak forests, but oak seedlings must be in the dormant stage.

The forest regeneration phase in Sweden commonly involves mechanical soil preparation followed by planting of Scots pine or Norway spruce seedlings. The prepared soil offers planting positions with different properties, including decreased damage by pine weevil (Hylobius abietis L.). Nitrogen fertilization can be applied at the time of planting to aid establishment of the seedlings. In this study we compared the effect of organic nitrogen-fertilization for different planting positions, and seedling sizes on early survival and growth of Scots pine and Norway spruce seedlings. The main planting positions were capped mound, hinge, and mineral soil. Seedlings planted close to organic material were categorized as “low quality positions”, since proximity to organic material increase pine weevil attraction. Higher mortality rates related to pine weevil damage were recorded for seedlings planted in the low-quality positions, regardless of seedling size or N-fertilization. Pine weevil attack rates increased with increasing seedling size. Growth was in general lowest in mineral soil positions. The effect of organic N-fertilization on growth was positive for spruce regardless of planting positions and seedling size, while depending on planting position and seedling size for pine, indicating that effects of organic N-fertilization depend on seedling species, -size and planting position.

During the production of furniture, large amounts of waste of these materials are generated, which are most often stored in warehouses without a specific purpose for their subsequent use. In highly developed countries, as many as 25 million tons of textile waste are produced annually, of which approximately 40% is non-clothing waste, such as carpets, furniture and car upholstery. The aim of the research was to produce and evaluate the dry-formed high-density fiberboards (HDF) with various shares of recycled particles of natural leather used in upholstery furniture production at different contents (1, 5 and 10% by weight). Mechanical properties (modulus of rupture, modulus of elasticity and screw withdrawal resistance) and physical properties (density profile, thickness swelling after water immersion, water absorption, surface absorption) were tested. The density profile and contact angle of natural leather have been also characterized. The results show that increasing the content of leather particles in HDF mostly has a positive effect on mechanical properties, especially screw withdrawal resistance and water absorption. It can be concluded, that, depending on the further use of HDF, it is possible to use recovered upholstery leather particles as a reasonable addition to wood fibers in HDF technology.

Leaf mass per area (LMA) is a key structural parameter that reflects the functional traits of leaves and plays a vital role in simulating the material and energy cycle of plant ecosystems. In this study, vertical whorl-by-whorl sampling of LMA was conducted in a young Larix principis-rupprechtii plantation during the growing season at the Saihanba Forest Farm. The vertical and seasonal variations in LMA were analysed. Subsequently, a predictive model of LMA was constructed. The results revealed that the LMA varied significantly between different crown whorls and growing periods. In the vertical direction of the crown, the LMA decreased with increasing crown depth, but the range of LMA values from the tree top to the bottom was, on average, 30.4 g/m2, which was approximately 2.5 times greater in the fully expanded phase than in the early leaf-expanding phase. The LMA exhibited an allometric growth trend that increased during the leaf-expanding phase and then tended to stabilize. However, the range of LMA values throughout the growing period was, on average, 40.4 g/m2. Among the univariate models, the leaf dry matter content (LDMC) performed well (Ra2=0.45, RMSE=13.48 g/m2) in estimating the LMA. The correlation between LMA and LDMC significantly differed at different growth stages and at different vertical crown whorls. The dynamic predictive model of LMA constructed with the RDINC and DOY as independent variables was reliable in both the assessments (Ra2=0.68, RMSE=10.25 g/m2) and the validation (MAE=8.05 g/m2, FI=0.682). Dynamic simulations of crown LMA provide a basis for elucidating the mechanism of crown development and laying the foundation for the construction of an ecological process model..

(1) Background: Brassinosteroids (BRs) are an important hormone that participates in almost all stages of plant growth and development, and sterol dehydrogenase is a key enzyme that is involved in the biosynthesis of BRs. However, the steroid dehydrogenase gene family in Populus yunnanensis Dode (P. yunnanensis) has not been studied; (2) Methods: The PyDET2 gene family was identified and bioinformatics analyzed. Three genes were screened based on the RNA-seq of stem tip, the PyDET2e was further investigated by RT-qPCR (real-time quantitative polymerase chain reaction) and subcellular localization; (3) Results: We identified 14 DET2 family genes in P. yunnanensis that were classified into 4 groups according to sequence similarity and phylogenetic relationship, and 10 conserved protein motifs had been identified. The gene structure, chromosome distribution, collinearity, and codon preference of all PyDET2 genes identified in the genome of P. yunnanensis were analyzed. The codon of this family is biased to the end of A/U, and natural selection has a great influence on it. The expression level of PyDET2e in September was higher than in July, and it was significantly expressed in stems, stem tips, and leaves. The PyDET2e protein was localized in chloroplasts; (4) Conclusions: The PyDET2e is involved in the development of P. yunnanensis in the rapid growth stage. The systematic analysis provided a basis for the genome-wide identification of genes related to brassinolide biosynthesis processes in P. yunnanensis, and laid a foundation for the study on the mechanism of rapid growth of P. yunnanensis.

To understand how the thinning strategies impacts on wood quality and quantity for different purposes is of interest, considering that the management of plantations is carried out with parameters that have yet to be validated for different growth conditions. This work evaluated contrasting thinning regimes applied early at two moments of the crop cycle. With an initial population of 840 trees.ha-1, two thinning with populations ranging from 700 to 400, and from 400 to 100 trees.ha-1 were applied at 1.5 and 7.3 years, respectively. Growth analyses were carried out from the ages of 1.5 to 20.8 years considering: total height, diameter at breast height, individual volume, total and commercial volume per hectare, mean annual increase and current annual increase. At final age, contrasting populations of 100, 250 and 400 trees.ha-1 were sampled to assess wood density, and mechanical properties (bending and compression on small scale clear samples). The values of individual growth and wood properties are related to a Stand Density Index to understand the effect of competition on those values. The results allow us to identify the thinning schemes that record the most significant individual and per-hectare growth (both in thinning and clear felling) and the optimal harvest time under specific growth conditions. We assessed the proportions of commercial logs for sawmill and pulp uses, providing valuable inputs for a subsequent economic analysis of thinning regimes seeking for the most convenient combination of wood products. Wood's physical and mechanical properties assessed were barely affected by contrasting levels of competition between trees, therefore the decision of the silvicultural system to implement will depend on production and economic criteria.

The European Union's current pressure on Member States to adopt the Green Deal and the Fit for 55 package is leading to an accelerated drive to put in place measures to meet the 2030 climate targets. At the same time, many discussions at international bilateral meetings of EU country representatives raise the question of the realism of setting climate targets and therefore the ability to meet these commitments. The results elaborated in this analytical study offer a realistic picture of the possibilities of meeting strategic climate targets using the example of the use of forest dendromass for the ability to achieve a 22% share of renewable energy sources (RES) in gross final energy consumption by 2030 in the Czech Republic. The study points out that at present the use of forest dendromass from primary pro-duction is at its maximum and meeting the climate targets for increasing the share of RES in the energy mix represents a major problem in the long term. The findings published in this study also point to the objective threat of increased use of dendrmass in the energy sector to the maintenance of sustainable forest management and the preservation of forest quality.

The issue of optimising the initial stand density (ISD) of tree plantations has high practical importance. The objective of this study was to nondestructively evaluate the influence of the initial stand density of Scots pine plantations located in the European part of the Russian Federation on wood basic density (BD), moisture content (MC), ultrasound velocity (UV), latewood content, and drilling resistance (DR). 45-year-old trees with stand densities of 500, 1000, 3000, 5000, and 10000 trees/ha were tested by a 5-cm-long core sample for gravimetric MCGM and BD, by PULSAR-2.2 for UV along the height (UVH) and through the tree trunk diameter (UVD), by the IML-RESI PD-400 tool for DR, and by GANN HT 85T for MC based on the electrical resistance method (MCERM). A significant influence of ISD was found on DBH, UVD, MCGM, and MCERM. ISD had no significant impact on BD, UVH, and DR. The wood BD ranged from 356 to 578 kg/m-3, with a mean value of 434±3.3 kg/m-3, and was restricted by the soil and environmental factors. DBH and 70% MCERM were good indicators of tree vitality. Linear correlations between DBH and MCERM (R2=0.67), DBH and MCGM (R2=0.74), DR and BD (R2=0.71), and the two-factor model MCGM=f(DBH, BD), (R2=0.76) were found.

The southeast of Spain is one of the most arid and desertification-prone areas in continental Europe, with climate change contributing to this situation. Climatic conditions affect the availability of water in the plant structures of wild species, facilitating the onset and/or spread of forest fires and increasing aridity. The Region of Murcia, in southeastern Spain, has small forest stands of gall oak (Quercus faginea) with relict value. It is of interest to investigate the situation of these stands, allowing us to know about their distribution and their evolution in the face of climate change. For this purpose, previous dasometric, available from a specific stand, studies are considered to be contrasted with current data, individual trees were geolocated, and distribution maps of contrasting environmental conditions were created. In general, gall oak has been observed to be distributed up to 1200 m altitude, especially in shady areas and embedded valleys and north-northeast orientations. Importantly, there was a positive evolution of the vegetative development, with increments in the number of trees during the study period, despite some negative affections in specific areas due to climate change.

Reducing GHG emissions is a crucial challenge in urban areas, characterized by high energy consumption and reduced exposure to nature. In this context, the urban green system could play a pivotal role. In the literature, scholars analyzed both the ability of species-specific and layout-specific green infrastructures to increase carbon sequestration and the best location sites of new green infrastructures, to increase the provision of overall ecosystem services. There is a lack of studies helping green urban planners and designers choose where and which green infrastructure to implement, based on vegetation species-specific performance and local carbon emissions of city components. This paper uses tree inventory data from a medium-sized city in central Italy (Perugia) to develop a spatial analysis of the urban parks' performance in carbon sequestration. Then, the method evaluates the carbon emission of a public city building to generate a spatialized balance between buildings’ demand and trees’ supply, to support local decisions about the best locations for new green infrastructures and the choice between species. The paper contributes to GIS-based tools that vary the recommended location sites and species for new green infrastructures based on the demanded ecosystem service.

Evapotranspiration (ET) is a major component of water budget in Bottomland Hardwood Forests (BHF) and is driven by a complex intertwined suite of meteorological variables. The understanding of these interdependencies leading to seasonal variations in ET is crucial in better informing water resource management in the region. We used a structural equation modeling approach to analyze the drivers of ET using Eddy covariance water and heat flux data collected from a BHF, located in the Russel Sage Wildlife Management Area (RSWMA). It consists of mature closed-canopy deciduous hardwood trees with an average canopy height of 27 m. Factor analysis was used to characterize the shared variance among drivers and path analysis was used to quantify independent contributions of individual drivers. In our results, ET and net radiation (Rn) showed similar variability patterns with Vapor Pressure Deficit (VPD) and temperature in Spring, Summer, and Autumn seasons while they differ in Winter season. The path analysis shows that Rn has the strongest influence on ET variations via direct and indirect pathways. In the deciduous forests like BHFs, our results suggest ET is more energy-dependent during growing season (Spring and Summer) and early non-growing season (Autumn) while more temperature-dependent during winter season.

A dataset collected from Central-South Finland is used to investigate the mortality of boreal trees. The mortality rate is found to be the order of three times that predicted by earlier Nordic mortality models, being in the upper range of international literature observations. Small subpopulations of any tree species tend to die out. Mortality of downy birch increases with stand basal area, as well as with stand age. Mortality of Norway spruce and silver birch increases after 100 years, while that of Scots pine is invariant to age. As the relative loss rate of basal area is insensitive to stand basal area, the mortality of trees does not strongly regulate thinning practices.