This study evaluates the multifactorial spatial modelling used to assess vulnerability of the Düzlerçamı (Antalya) forest ecosystem to climate change. This was done to produce data, to develop tools to support decision-making and the management of vulnerable Mediterranean forest ecosystems affected by climate change, and to increase the ability of these forest ecosystems to adapt to global change. Based on regionally averaged future climate assessments and projected climate indicators, both the study site and the western Mediterranean sub-region of Turkey will probably become associated with a drier, hotter, more continental and more water-deficient climate. This analysis holds true for all future scenarios, with the exception of RCP4.5 for the period from 2015 to 2030. However, the present dry-sub humid climate dominating this sub-region and the study area shows a potential for change towards more dry climatology and for it to become semiarid between 2031 and 2050 according to the RCP8.5 high emission scenario. All the observed and estimated results and assessments summarized in this study show clearly that the densest forest ecosystem in the southern part of the study site, characterized by mainly Mediterranean coniferous and some mixed forest and maquis vegetation, will very likely be influenced by medium and high degrees of vulnerability to future environmental degradation, climate change and variability.

Carbon sinks constitute an important element within the complex phenomenon of global climate change, and forest ecosystems are important global carbon sinks. The Natural Forest Protection Program (NFPP) is an ecological program in China that was established after catastrophic flooding in the country in 1998. The goals of the NFPP are to curb the deterioration of the ecological environment, strengthen the protection and restoration of habitat to increase biodiversity, and rehabilitate natural forests to support sustainable development in forest regions. This study looked at changes in carbon sequestration in a forested area of northeast China after the inception of the NFPP. The program divides China’s natural forests into three classes—commercial and two types of noneconomic forests—that are subject to management regimes prescribing varying levels of timber harvest, afforestation, and reforestation. During the 18-year period from 1998 to 2015, the total amount of carbon sequestration increased at an average annual rate of 0.04 MT C. This trend reflects a transformation of forest management practices after implementation of the NFPP that resulted in prohibited and/or restricted logging and tighter regulation of allowable harvest levels for specific areas. In documenting this trend, guidelines for more effective implementation of forestry programs such as the NFPP in other countries in the future are also suggested.

Height–diameter relationships are essential elements of forest assessment and modeling efforts. In this work, two linear and eighteen nonlinear height–diameter equations were evaluated to find a local model for Oriental beech (Fagus orientalis Lipsky) in the Hyrcanian Forest in Iran. The predictive performance of these models was first assessed by different evaluation criteria: adjusted R² (R_adj ²), root mean square error (RMSE), relative RMSE (%RMSE), bias, and relative bias (%bias) criteria. The best model was selected for use as the base mixed-effects model. Random parameters for test plots were estimated with different tree selection options. Results show that the Chapman–Richards model had better predictive ability in terms of adj R² (0.81), RMSE (3.7 m), %RMSE (12.9), bias (0.8), %Bias (2.79) than the other models. Furthermore, the calibration response, based on a selection of four trees from the sample plots, resulted in a reduction percentage for bias and RMSE of about 1.6–2.7%. Our results indicate that the calibrated model produced the most accurate results.

The aim of this study was to estimate a basal area growth model for individual trees in uneven-aged Caspian forests. A survey was conducted in order to find a natural forest without any harvesting activities, a so called ‘untouched forest’ and an area was selected from the Iranian Caspian forest. Three sample plots in the same aspect and of the same forest type were selected. In each plot, total tree height, diameter at breast height, distance of neighbor trees and azimuth were measured. Thirty trees were selected and drilled with increment borer to determine the increment model. Regression analysis was used to estimate the growth model. Results show that, for individual trees, there is a significant nonlinear relationship between the annual basal area increment, as the dependent variable, and the basal area. The results also show that the basal area of competing trees has a positive influence on growth. That the increment is higher with more competing neighboring trees is possibly because plots with higher volume per hectare and more competition, most likely also have higher site index or better soil or better site productivity than the plot with lower volume per hectare.

Understanding forest ecosystem evapotranspiration (ET) is crucial for water-limited environments, particularly those that lack adequate quantified data such as the lower Heihe River basin of northwest China which is primarily dominated by Tamarix ramosissima Ledeb. and Populus euphratica Oliv. forests. Accordingly, we selected the growing season for 2 years (2012 and 2014) of two such forests under similar meteorological conditions to compare ET using the eddy covariance (EC) technique. During the growing seasons, daily ET of T. ramosissima ranged from 0.3 to 8.0 mm day⁻¹ with a mean of 3.6 mm day⁻¹, and daily ET of P. euphratica ranged from 0.9 to 7.9 mm day⁻¹ with a mean of 4.6 mm day⁻¹ for a total of 548 and 707 mm, respectively. The significantly higher ET of the P. euphratica stand was directly linked to high soil evaporation rates under sufficient water availability from irrigation. When the soil evaporation was disregarded, water use was comparable to two contrasting riparian forests, a P. euphratica forest with a total transpiration of 465 mm and a T. ramosissima forest with 473 mm. Regression analysis demonstrated that climate factors accounted for at least 80% of ET variation in both forest types. In conclusion, water use of the riparian forests was low and comparable in this arid region, that suggest the long-term plant adaptation to the local climate and conditions of water availability.

Morphological variation based on eight measured and four derived traits was studied to establish whether there was significant variation between populations and to identify the influence of the altitude on morphological differentiation among 44 natural stands of common oak (Quercus robur L.) in Bosnia and Herzegovina, ranging from 82 to 860 m. The results point to significant intra- and inter-population differences. Elevation-related variation is less pronounced and determined largely by microclimatic factors. The results could provide management strategies for species reintroduction in the study area. There are no differences in leaf morphology between the different branches of individual trees. However, there are important variations between the altitudinal groups and closely linked to environmental factors in all traits. An important recommendation is to use seeds from oak with attention to their altitudinal origin.

Fasiakhali Wildlife Sanctuary is a protected area composed of tropical remnant rainforest that harbor substantial number of large, old Garjan (Dipterocarpus spp.) trees. The present study assessed composition, structure and diversity of the species in this protected area. A total of 32 trees species were recorded with DBH ≥ 11 cm belonging to 24 genera and 19 families. The forest is low in plant diversity as represented by Shannon–Wiener diversity and Simpson Dominance indices. Dipterocarpus turbinatus was the most dominant species with maximum relative density, frequency, dominance, and importance value index. Syzygium firmum and Tectona grandis followed in terms of dominance. The structural composition indicated higher number of individuals in the medium growth classes (41 to < 511 cm DBH and 16–20 m height ranges), whereas D. turbinatus was the only species that dominated most of the growth classes. Poor stem density in lower growth classes indicated meager recruitment of regeneration which may be due to lower annual precipitation, increased grazing and encroachments. This study will help to understand the patterns of tree species composition and diversity in the remnant dipterocarp forests of Bangladesh. It will also contribute to identifying threatened plants to undertake D. turbinatus based conservation and sustainable management of the Fasiakhali Wildlife Sanctuary.

Estimating individual tree biomass is critical to forest carbon accounting and ecosystem service modeling. In this study, we developed one- (tree diameter only) and two-variable (tree diameter and height) biomass equations, biomass conversion factor (BCF) models, and an integrated simultaneous equation system (ISES) to estimate the aboveground biomass for five conifer species in China, i.e., Cunninghamia lanceolata (Lamb.) Hook., Pinus massoniana Lamb., P. yunnanensis Faranch, P. tabulaeformis Carr. and P. elliottii Engelm., based on the field measurement data of aboveground biomass and stem volumes from 1055 destructive sample trees across the country. We found that all three methods, including the one- and two-variable equations, could adequately estimate aboveground biomass with a mean prediction error less than 5%, except for Pinus yunnanensis which yielded an error of about 6%. The BCF method was slightly poorer than the biomass equation and the ISES methods. The average coefficients of determination (R ²) were 0.944, 0.938 and 0.943 and the mean prediction errors were 4.26, 4.49 and 4.29% for the biomass equation method, the BCF method and the ISES method, respectively. The ISES method was the best approach for estimating aboveground biomass, which not only had high accuracy but also could estimate stocking volumes simultaneously that was compatible with aboveground biomass. In addition, we found that it is possible to develop a species-invariant one-variable allometric model for estimating aboveground biomass of all the five coniferous species. The model had an exponent parameter of 7/3 and the intercept parameter a ₀ could be estimated indirectly from stem basic density (a ₀ = 0.294 ρ).

We quantified deviations in regional forest biomass from simple extrapolation of plot data by the biomass expansion factor method (BEF) versus estimates obtained from a local biomass model, based on large-scale empirical field inventory sampling data. The sources and relative contributions of deviations between the two models were analyzed by the boosted regression trees method. Relative to the local model, BEF overestimated accumulative biomass by 22.12%. The predominant sources of the total deviation (70.94%) were stand-structure variables. Stand age and diameter at breast height are the major factors. Compared with biotic variables, abiotic variables had a smaller overall contribution (29.06%), with elevation and soil depth being the most important among the examined abiotic factors. Large deviations in regional forest biomass and carbon stock estimates are likely to be obtained with BEF relative to estimates based on local data. To minimize deviations, stand age and elevation should be included in regional forest-biomass estimation.

Pre-sowing treatments are expected to increase seed germination. This evaluates response to pre-sowing treatments and the growth performance of two native and rare tree species, Garuga pinnata Roxb. and Vitex glabrata R. Br. The hard seed coats were treated by rubbing with sand paper, nail clipping, and immersion in water and acid (H₂SO₄). Results indicate that G. pinnata showed a 90% germination rate and 30% germination energy when seed coats were nicked with a nail clipper. Rubbing with sand paper was the best pre-sowing treatment for V. glabrata, resulting a 80% germination rate and 30% germination energy. G. pinnata and V. glabrata seedlings from seeds soaked 24 h in water resulted in maximum heights and collar diameters. These were significantly higher (at p < 0.05) than those of other treatments. The results indicate that scarification or nicking of seeds may have some negative impacts on seedling growth. Therefore, it is difficult to recommend a pre-sowing treatment of seeds for achieving both maximum germination and good early seedling growth.

Semecarpus kurzii Engl. is an important ethnomedicinal plant used for curing tumours, inflammation, fever and pain, and is also a source of iso ricinoleic acid. During the present investigation, effect of chemical pre-treatments on germination and seedling growth revealed significant differences. Different pre-treatments could improve germination and treatment with KNO₃ (9.9 mM) was significantly superior (94%) to the untreated control (76%). Mean daily germination varied among the treatments (0.90–4.14 seeds per day), when compared with 2.27 seeds per day in control. Mean germination time was significantly reduced from 22.14 days (control) to 16.40 days (19.8 mM KNO₃) and 17.16 days (1.45 mM GA₃). Treatment with KNO₃ (19.8 mM) and GA₃ (1.45 and 2.90 mM) significantly reduced the time for 50% germination. Treatment with higher concentrations of GA₃ and KNO₃ exhibited significantly faster germination initiation (11.0 and 12.0 days, respectively) over the control (17.0 days). Seedling vigour index was not improved by pre-treatments. Chemical treatments did not improve shoot growth, collar thickness, or number of seedling leaves; however, root growth was significantly improved over control. Treatment with GA₃ (2.90 mM) promoted leaf elongation but reduced leaf width significantly. Treatment with KNO₃ and GA₃ could be recommended to obtain healthy seedlings for establishing new plantations of this important medicinal plant species.

Afforestation has been implemented to reduce soil erosion and improve the environment of the Loess Plateau, China. Although it increased soil organic carbon (SOC), the stability of the increase is unknown. Additionally, the variations of soil inorganic carbon (SIC) following afforestation needs to be reconfirmed. After planting Robinia pseudoacacia, Pinus tabuliformis, and Hippophae rhamnoides on bare land on the Loess Plateau, total soil carbon (TSC) was measured and its two components, SIC and SOC, as well as the light and heavy fractions within SOC under bare lands and woodlands at the soil surface (0–20 cm). The results show that TSC on bare land was 24.5 Mg ha⁻¹ and significantly increased to 51.6 Mg ha⁻¹ for R. pseudoacacia, 47.0 Mg ha⁻¹ for P. tabuliformis and 39.9 Mg ha⁻¹ for H. rhamnoides. The accumulated total soil carbon under R. pseudoacacia, P. tabuliformis, and H. rhamnoides, the heavy fraction (HF-SOC) accounted for 65.2, 31.7 and 76.2%, respectively; the light fraction (LF-SOC) accounted for 18.0, 52.0 and 4.0%, respectively; SIC occupied 15.6, 15.3 and 19.7%, respectively. The accumulation rates of TSC under R. pseudoacacia, P. tabuliformis, and H. rhamnoides reached 159.5, 112.4 and 102.5 g m⁻² a⁻¹, respectively. The results demonstrate that afforestation on bare land has high potential for soil carbon accumulation on the Loess Plateau. Among the newly sequestrated total soil carbon, the heavy fraction (HF-SOC) with a slow turnover rate accounted for a considerably high percentage, suggesting that significant sequestrated carbon can be stored in soils following afforestation. Furthermore, afforestation induces SIC sequestration. Although its contribution to TSC accumulation was less than SOC, overlooking it may substantially underestimate the capacity of carbon sequestration after afforestation on the Loess Plateau.

The ecological effects of eucalypt plantations (EPs) have garnered increasing attention. To understand their effect on soil quality at a landscape scale, and to determine whether soil quality parameters differ due to different stand types, we evaluated soil characteristics in twenty-one groups of EPs, Pinus massoniana Lamb. plantations (PMPs) and natural broadleaved forests (NBFs) across Guangdong Province, China. Both the physical characteristics of soil hydrology and the properties of soil nutrients in A and B horizons were determined. Results showed that, compared to NBFs, EPs and PMPs produced a shallower litter layer, reduced canopy density, higher soil bulk density, significantly lower total porosity, non-capillary porosity, total water volume, and hygroscopic water in the A horizon (P < 0.05). Moreover, total N, available K, and soil organic carbon (SOC) in EPs and PMPs were significantly lower than in NBFs. EPs and PMPs did not differ significantly in N, P or K content, but PMPs had significantly lower SOC and boron in the A horizon than EPs. Low pH and poor capacity to buffer acidification generally occurred in all cover types. Both EPs and PMPs showed a decline in soil properties relative to NBFs, but EPs and PMPs exhibited no significant difference. These results indicate that actions are needed to ameliorate the potential negative effects on soil quality in forestry plantations.

Studies on litterfall and decomposition provide estimations of decomposition rates of different ecosystems. This is key information to understanding ecosystem dynamics and changes in a scenario of global warming. The objective of this research was to assess litterfall production, the potential deposition of macro and micronutrients through leaf and twig fall as well as macronutrient—use efficiency in three forest ecosystems at different altitudes: a pine forest mixed with deciduous species (S1); a Quercus spp. forest (S2); and, a Tamaulipan thornscrub forest (S3). Total annual litterfall deposition was 594,742 and 533 g m⁻² for S1, S2 and S3. Leaf litter was higher (68%) than twigs (18%), reproductive structures (8%) or miscellaneous material (6%). Micronutrient leaf deposition was higher for Fe followed by Mn, Zn and Cu. Macronutrient leaf deposition was higher for Ca followed by K, Mg and P. Even though P deposition in leaves and twigs was lower than other macronutrients, its nutrient use efficiency was higher than Ca, Mg or K. Altitude and species composition determine litter and nutrient deposition, with higher values at mid-altitudes (550 m). Altitude is an important factor to consider when analyzing litter production as well as nutrient deposition as shown in this study. Litter production and nutrient deposition are expected to change in a scenario of global warming.

Biochemical changes associated with flowering in Bambusa arundinacea Linn and Bambusa nutans Wall. ex Munro were analyzed. Gregarious flowering was initiated in natural areas and plantations of B. arundinacea in late 2014 and reached full bloom in early 2015, whereas sporadic flowering recorded during 2014–2015 in vegetatively propagated plants of B. nutans. Leaf and nodal shoot samples from flowering culms/shoots and nonflowering culms/shoots were collected in February 2015 at the initiation of fruit filling, then analyzed and compared for soluble sugars, phenols and peroxidase activity. In both species sugars were higher in leaves of flowering culms/shoots and lower in nodal shoots of flowering culms/shoots compared to the nonflowering. Phenols were lower in leaves and nodal shoots of flowering B. arundinacea, but higher in leaves and decreases in nodal shoots of B. nutans. Peroxidase activity increases in leaves and nodal shoots of B. arundinacea after flowering but increases in nodal shoots and decreases in leaves of B. nutans.

Fine roots are important in root absorption of nutrient and water, and in root turnover. Accurate definition of fine roots is a prerequisite to improved estimation of the physiological and ecological functions of forest ecosystems. Root development and physiological functions are reflections of root anatomical structure. In this study, the anatomical structures of different root orders were analyzed by examining paraffin sections of one-year old Fraxinus mandshurica seedlings. One-year-old F. mandshurica seedlings had over five root orders. The root anatomical structures of all orders showed more differences. First and second order roots consisted of four sections: the epidermis, cortex, pericycle, and vascular bundles. Fourth and fifth order roots were mainly composed of the skin and peripheral vascular bundles (including the xylem and phloem). Third order roots had root epidermal and cortical structures, but the quantity and integrity of the cortical cells were inferior to those of the first and second order roots, and superior to those of the fourth and fifth order roots. All the first and second order roots and some third order roots with discontinuous cork layer (< 0.4 mm in diameter), but not the fourth and fifth order roots, were the fine roots of one-year old F. mandshurica seedlings. Although they had similar diameters, different portions of root systems had different anatomical structures and therefore, vary in capacity to absorb water and nutrients. Fine roots were accurately defined by root diameter, branch orders, and anatomical structural features of one-year old F. mandshurica seedlings.

The chemical compositions of the dichloromethane extracts of inner and outer barks from six Pinus species (P. elliotii, P. oocarpa, P. caribeae, P. merkusii, P. montezumae, and P. insularis) grown in Indonesia were investigated by GC and GC–MS. Generally, the amounts of extractive contents were higher in the inner bark than in the outer bark except for P. merksuii. Fatty acids, monoterpenes, sesquiterpenes, resin acids, triterpenoids, and steroids were detected and quantified. Inner and outer barks differed not only in content of these compounds but also in their composition. Fatty acids and alcohols were the major classes of lipophilic compounds in the outer bark of P. caribeae, P. insularis, and P. montezumae. Steroids and triterpenoids were the dominant compounds identified in the inner bark of P. elliotii, P. insularis, and P. merkusii. Resin acids were the most abundant group in the inner bark of P. oocarpa whereas monoterpenes and sesquiterpenes were recorded in minor quantities in both bark layers of all species.

Microbial functional diversity and enzymatic activities are critical to maintaining material circulation during litter decomposition in forests. Thinning, an important and widely used silvicultural treatment, changes the microclimate and promotes forest renewal. However, how thinning affects microbial functional diversity and enzymatic activities during litter decomposition remains poorly understood. We conducted thinning treatments in a Chinese fir plantation in a subtropical region of China with four levels of tree stem removal (0, 30, 50, and 70%), each with three replicates, and the effects of thinning on microbial functional diversity and enzymatic activities were studied 7 years after treatment by collecting litter samples four times over a 1-year period. Microbial functional diversity and enzymatic activities were analyzed using Biolog Ecoplates (Biolog Inc., Hayward, CA, USA) based on the utilization of 31 carbon substrates. Total microbial abundance during litter decomposition was lower after the thinning treatments than without thinning. Microbial functional diversity did not differ significantly during litter decomposition, but the types of microbial carbon-source utilization did differ significantly with the thinning treatments. Microbial cellulase and invertase activities during litter decomposition were significantly higher under the thinning treatments due to changes in the litter carbon concentration and the ratios of carbon and lignin to nitrogen. The present study demonstrated the important influence of thinning on microbial activities during litter decomposition. Moderate-intensity thinning may maximize vegetation diversity and, in turn, increase the available substrate sources for microbial organisms in litter and promote nutrient cycling in forest ecosystems.

Arthropod communities and epiphytic plants associated with tree canopies have been widely studied and have revealed a great diversity of organisms; however, the community hosted by parasitic plants, such as dwarf mistletoes, remains poorly known. In the coniferous forests of North America, dwarf mistletoe infection (Arceuthobium spp.) significantly damages the health of the forest, causing large financial losses for the forest industry, but it also positively affects diversity, especially of mammals and birds. This study examined the attributes of the arthropod communities associated with two species of dwarf mistletoe [Arceuthobium globosum Hawksw. & Wiens and A. vaginatum (Humb. & Bonpl. ex Willd.) J. Presl] and their host Pinus hartwegii Lindl. In 2010, in five sites located in Zoquiapan (Central Mexico), we collected plant tissue from the three species bimonthly. Arthropods were separated from the plant tissue and identified to the finest level possible. We collected 32,059 individuals, for which 51 morphospecies were identified, belonging to 15 taxonomic orders; the most abundant orders for the three plants were Prostigmata, Thysanoptera and Homoptera. The community associated with P. hartwegii had the highest value of diversity (H′ = 1.47; A. globosum, H′ = 0.64; A. vaginatum, H′ = 0.68) and species richness (S = 40; A. globosum, S = 30; A. vaginatum, S = 35); while abundance was significantly higher for the mistletoes (A. globosum, n = 407 individuals/sample; A. vaginatum, n = 536 individuals/sample; P. hartwegii, n = 134 individuals/sample). Species richness, abundance and diversity were significantly different for the three studied plants, as well for sampling month and the interaction of these two factors (except for diversity). The results suggest that the canopy of P. hartwegii is an important element in the ecosystem, providing a mosaic of resources and conditions to the associated fauna. We also propose that mistletoes are key species within the forest canopy, as they greatly influence the establishment of diverse organisms, particularly arthropods.

Saproxylic insect assemblages are essential functional components of forest ecosystems that can be affected by forest management. We used a split-plot ANOVA design to analyze differences in selected saproxylic insects (all arthropod orders and dipteran and parasitic hymenopteran families) emerging from dead wood of sites with different logging histories (horse-logged, mechanically-logged and unlogged), tree species (Populus and Picea), stage of decay (early- and late-decay stages) and posture (standing and downed logs) in the boreal forest of central Canada. No clear effects of logging history were seen for the studied taxa; however, interaction between logging history and other dead wood features was apparent. Cecidomyiidae consistently emerged more from Populus than from Picea dead wood. Most of the studied saproxylic families were more abundant in late-decay than in early-decay wood. Dipterans of the Cecidomyiidae, Ceratopogonidae, Empididae, Mycetophilidae and Sciaridae families, and hymenopterans of the Diapriidae and Ichneumonidae families were significantly more abundant in downed than in standing dead wood. In contrast, Mymaridae was most abundant in standing dead wood. Our study provides evidence that some insects at high taxonomic levels respond differently to dead wood quality, and this could inform future management strategies in the boreal forest for the conservation of saproxylic fauna and their ecological functions.

Bamboo is nature’s wonderful gift historically associated with the rural population of the Bodoland Territorial Area Districts. However, indiscriminate use of the resource and the ambiguity in the identification of bamboos in the absence of flowering characters pose a potential risk to the bamboo germplasm. Therefore, we considered revising the taxonomic positions and phylogenetic relationships among 15 tropical bamboo species using 35 key morphological descriptors (MD) to assess the reliability of vegetative characters in identifying species. The phylogenetic tree constructed from the similarity matrix, derived from an unweighted pair group method of analysis (UPGMA) of the 35 MDs, marginally deviated from the conventional taxonomic positions of the bamboo species. While the two varieties, one forma of Bambusa vulgaris (var. Vittata, var. Vulgaris, fo. Waminii) and two species of the genus Dendrocalamus (D. giganteus and D. hamiltonii) clustered together in a single clade, and D. strictus was distantly placed from their congeners. This discrepancy with the conventional classification might have ensued since only vegetative characters such as culm anatomy, culm sheath, leaf, and leaf sheath were considered in the present study. While the phylogenetic relationship among the 15 tropical bamboos (computed from exhaustive MDs) grossly corroborate the conventional taxonomic grouping, a molecular-marker-based multidisciplinary approach should resolve the remaining conflicts in bamboo identification.

Fifty-three larch interspecific hybrid clones (Larix kaempferi × L. gmelini) and their parent clones were used for growth curve analysis of height variations. The growth curves of the 55 clones were ‘S’-shaped and 36 exhibited similar curves as the male parent. The coefficients of the logistic models were higher than 0.943, indicating that our results were effective in the simulation of the growth curves. ANOVA analysis showed significant differences in height of different clones (P < 0.01). Average date of maximum height growth was Day 173, and average duration of rapid growth lasted for 50 days. Annual average increase in height was 9.7 cm d⁻¹ and daily average increase was 0.2 cm. The ratio of GR to the total annual increase in height ranged from 51.2 to 68.8%, with the average being 59.8%. There was a positive correlation between k values and plant heights which benefited from the evaluation of early plant height. There was also a positive correlation between GR (growth stage), GD (plant height) and annual increase in height. These results are informative to the evaluation of the elite clone selection and provide a theoretical basis for breeding and management.

Mapping forests is an important process in managing natural resources. At present, due to spectral resolution limitations, multispectral images do not give a complete separation between different forest species. In contrast, advances in remote sensing technologies have provided hyperspectral tools and images as a solution for the determination of species. In this study, spectral signatures for stone pine (Pinus pinea L.) forests were collected using an advanced spectroradiometer “ASD FieldSpec 4 Hi-Res” with an accuracy of 1 nm. These spectral signatures are used to compare between different multispectral and hyperspectral satellite images. The comparison is based on processing satellite images: hyperspectral Hyperion, hyperspectral CHRIS-Proba, Advanced Land Imager (ALI), and Landsat 8. Enhancement and classification methods for hyperspectral and multispectral images are investigated and analyzed. In addition, a well-known hyperspectral image classification algorithm, spectral angle mapper (SAM), has been improved to perform the classification process efficiently based on collected spectral signatures. The results show that the modified SAM is 9% more accurate than the conventional SAM. In addition, experiments indicate that the CHRIS-Proba image is more accurate than Landsat 8 (overall accuracy 82%, precision 93%, and Kappa coefficient 0.43 compared to 60, 67%, and 0.035, respectively). Similarly, Hyperion is better than ALI in mapping stone pine (overall accuracy 92%, precision 97%, and Kappa coefficient 0.74 compared to 52, 56%, and − 0.032, respectively).

We developed a forest type classification technology for the Daxing′an Mountains of northeast China using multisource remote sensing data. A SPOT-5 image and two temporal images of RADARSAT-2 full-polarization SAR were used to identify forest types in the Pangu Forest Farm of the Daxing′an Mountains. Forest types were identified using random forest (RF) classification with the following data combination types: SPOT-5 alone, SPOT-5 and SAR images in August or November, and SPOT-5 and two temporal SAR images. We identified many forest types using a combination of multitemporal SAR and SPOT-5 images, including Betula platyphylla, Larix gmelinii, Pinus sylvestris and Picea koraiensis forests. The accuracy of classification exceeded 88% and improved by 12% when compared to the classification results obtained using SPOT data alone. RF classification using a combination of multisource remote sensing data improved classification accuracy compared to that achieved using single-source remote sensing data.

Electrical pollution is a worldwide concern, because it is potentially harmful to human health. Trees not only play a significant role in moderating the climate, but also can be used as shields against electrical pollution. Shielding effects on the electric field strength under transmission lines by two tree species, Populus alba and Larix gmelinii, were examined in this study. The electrical resistivity at different heights of trees was measured using a PiCUS sonic tomograph, which can image the electrical impedance for trees. The electric field strength around the trees was measured with an elf field strength measurement system, HI-3604, and combined with tree resistivity to develop a model for calculating the electric field intensity around trees using the finite element method. In addition, the feasibility of the finite element method was confirmed by comparing the calculated results and experimental data. The results showed that the trees did reduce the electric field strength. The electric field intensity was reduced by 95.6%, and P. alba was better than L. gmelinii at shielding.

In this study, 2⁵ (five factors at two-level factorial design) design of experiment was applied to investigate a set of optimal machining parameters to achieve a minimum surface roughness value for Abies nordmanniana. Wood specimens were prepared using different values of spindle speed, feed rate, depth of cut, tool radius, and cutting directions. Average surface roughness $ \left( {R_{z} } \right) $ values were applied using a stylus. The objectives were to: (1) obtain the effective variables of wood surface roughness; (2) analyze which of these factors had an impact on variability in the CNC machining process; (3) evaluate the optimal cutting values within the range of different cutting levels of machining parameters. The results indicate that the design of experiment (DOE) based on the desirability function approach determined the optimal machining parameters successfully, leading to minimum R _a compared to the observed value. Minimum surface roughness values of tangential and radial cutting directions were 3.58 and 3.21 µm, respectively.

Plantation-grown progenies of Melia composita Willd. were studied for variability in several physical properties: density, radial and tangential shrinkage, longitudinal permeability of heartwood and sapwood. Furthermore, flat-sawn planks from each of the progeny were subjected to a quick-drying test for determination of kiln-drying schedule. The mean density of the species was 0.39 g cm⁻³ and the wood may be categorized as light wood. Mean radial shrinkage (%) for the species was 2.8% with progeny-wise variation in radial shrinkage from 1.56 to 4.11%. Mean tangential shrinkage (%) for the species was 5.54% with progeny-wise variation in tangential shrinkage from 3.69 to 7.71%. The resultant tangential-radial shrinkage ratio was 1.98 (less than two), which suggests that the wood is relatively stable with respect to drying behavior. Mean sapwood and heartwood longitudinal permeability of the species were 3.38 and 2.02 Darcy, respectively. Higher longitudinal permeability of sapwood and heartwood indicate better drying and preservative properties of the species. Terazawa quick-drying test method suggests that the species is less susceptible to drying defects. During the test, only moderate checks and cracks were observed. A tentative kiln-drying schedule was recommended based on these results.

As one of the main structural units in a building, a solid wood floor has significant strategic research value for low-carbon energy saving. Taking the production line of a solid larch wood floor as a case study, we assessed the environmental load during production based upon a life cycle assessment. Using GaBi 6.0 software, we analyzed the associated carbon sequestration during floor production, with the initial planting density serving as the disturbance factor in a modular analysis. The results indicated that the cutting and finishing steps have relatively intense, negative influences on the environment, whereas transportation, ripping, and trimming do not. Additionally, recycling biomass waste has the potential to reduce greenhouse gas emissions. When the initial planting density was 3.0 × 3.0 m, carbon sequestration was relatively high. Although the emissions of freshwater pollutants, volatile organic compounds, and fine particulate matter (matter with a 2.5-μm diameter) were comparatively high, the reduction of greenhouse gas emissions was still excellent at this planting density.