Sacred groves preserve a rich religious and socio-cultural heritage of Indian biodiversity from primeval times, due to their values. They act as a bridge between man and nature. Groves help to improve soil quality, replenish water resources and are pivotal for biodiversity conservation of plants and animals including rare, endemic, threatened, vulnerable species and ethnobotanical species. Most of India’s sacred groves are associated with a deity or a spiritual being, who protects the grove and local people. Vegetation cover of these groves has traditional ethnobotanical value, especially in the field of ethnomedicine, which accounts for the conservation of groves over the years. Numerous plant species from sacred groves are used according to tradition and culture to prevent or cure various health problems. However, modernisation, industrialisation, increased encroachment and misuse of forest resources increasingly threaten sacred groves. These treasures of nature must be conserved by formulating and applying new laws and policies while creating awareness among people about the value of sacred groves. Toward this aim, we review the distribution, ecological and socio-cultural significance of sacred groves of India and strategies to conserve them.

Osmotic stress promotes somatic embryogenesis of Fraxinus mandshurica, which leads to accumulation of reactive oxygen species (ROS). The single pieces of cotyledons of F. mandshurica were used as explants to induce somatic embryogenesis in osmotic-stress medium. Furthermore, the hydrogen peroxide (H₂O₂) content of explanted cells was varied by adding exogenous H₂O₂ or catalase solution to assess the effects of the exogenous H₂O₂ on somatic embryogenesis, intracellular H₂O₂ accumulation, and the relationship between signaling mediated by ROS or reactive nitrogen species. The results revealed that exogenous H₂O₂ (100‒300 μmol L^–1) increased the number of somatic embryos. On 60th day of exogenous H₂O₂ (200 μmol L^–1) treatment, the number of somatic embryos of explants treated, which was 136.54%, was higher than the control. Moreover, exogenous H₂O₂ (100 μmol L^–1) significantly increased the intracellular H₂O₂ content and enhanced the activities of superoxidase dismutase and peroxidase. Finally, exogenous H₂O₂ (100 μmol L^–1) activated the intracellular non-enzymatic pathway for nitric oxide (NO) synthesis. The somatic embryogenesis in broadleaf trees increases with the change of endogenic ROS content, and depends on the upregulation of antioxidant enzymes. Both H₂O₂ and NO, as signaling molecules, were found to be involved in the process of somatic embryogenesis in broadleaf trees. In the process of exogenous H₂O₂ promoting somatic embryogenesis, NO synthesis depended on non-enzymatic reactions. These results provide a scientific basis for resolving the mechanism by which ROS levels are regulated during somatic embryogenesis of broadleaf trees and establish a reasonable and efficient technology system for regulating somatic embryogenesis of trees.

Stomata control carbon and water vapor exchange between the leaves and the atmosphere, thus influencing photosynthesis and transpiration. Combinations of forest patches with different stand ages are common in nature, however, information of which stomatal traits vary among these stands and how, remains limited. Here, seven different aged forest stands (6, 14, 25, 36, 45, 55, and 100 years) were selected in typical temperate, mixed broadleaf-conifer forests of northeast China. Stomatal density, size and relative area of 624 species, including the same species in stands of different ages were selected. Stomatal density, size and relative area were distributed log-normally, differing across all species and plant functional groups. Stomatal density ranged from 4.2 to 1276.7 stomata mm^–2, stomatal size ranged from 66.6 to 8315.7 μm², and stomatal relative area 0.1–93.3%. There was a significant negative relationship between density and size at the species and functional group levels, while the relative stomatal area was positively correlated with density and size. Stomatal traits of dominant species were relatively stable across different stand ages but were significantly different for herbs. The results suggest that stomatal traits remain relatively stable for dominant species in natural forests and therefore, spatial variation in stomatal traits across forest patches does not need to be incorporated in future ecological models.

Betula platyphylla is a native tree species in northern China that has high economic and medicinal value. We developed an efficient protocol for the induction of somatic embryogenesis in B. platyphalla from immature zygotic embryos and assessed the effects of explant type, genotype, and plant growth regulators (PGRs) on embryogenic callus induction. Among the various explants evaluated, embryogenic callus was only produced from mature and immature zygotic embryos on medium with added 2,4-dichlorophenoxyacetic acid (2,4-D). Supplementation of 2,4-D-containing medium with cytokinins increased the frequency of embryogenic callus induction. On the 20 days after pollination, immature zygotic embryos that had been collected in mid-May yielded embryogenic tissue at the highest frequency (16.8%) when cultured on half-strength MS medium supplemented with 2.0 mg L⁻¹ 2,4-D and 0.2 mg L⁻¹ 6-benzylaminopurine (6-BA). The process of proliferation of embryogenic callus, somatic embryo formation, and subsequent plantlet conversion occurred under optimal culture conditions. When regenerated plants were transplanted to soil, 95% of them developed normally and grew vigorously. This somatic embryogenesis system required 3–4 months for the regeneration of B. platyphalla plantlets from immature zygotic embryos.

Mulberry (Morus alba L.) seedlings were used to test hydrogen peroxide (H₂O₂) as a potential systemic messenger in photosynthetic induction. The upper leaf of mulberry was dark-adapted for 45 min and then illuminated with photosynthetically active radiation (PAR) of 1000 μmol m⁻² s⁻¹. Photosynthetic induction and H₂O₂ content in the lower leaf was measured. The results show that pre-illumination of the upper leaf promoted photosynthetic induction and increased endogenous H₂O₂ in the lower leaf. Without pre-illuminating upper leaf, exogenous H₂O₂ treatment on the lower leaf promoted photosynthetic induction. The application of diphenyleneiodonium and trichloroacetic acid on petioles of the upper leaf inhibited H₂O₂ increase in the lower leaf, indicating that H₂O₂ transport was from upper leaves to lower leaves through the phloem. The results show that H₂O₂ might serve as a signal messenger to promote rapid induction of photosynthesis of leaves in lower parts of the canopy and enable plants to use light energy more efficiently.

Considering the expansion of forest plantations over the Brazilian territory and the imminent increase in air temperatures due to global warming, the search for technologies that ensure high levels of productivity and high quality plants in clonal nurseries is essential. Applying kaolin-based particle films (KBPF) has been used as a physical barrier to reduce the negative effects of excessive solar radiation and adverse temperatures. The effects of KBPF on production and physiological quality of eucalyptus mini-cuttings were evaluated during two different seasons. A randomized block design was used, consisting of five treatments and four replications. Five concentrations (0, 3%, 5%, 7%, and 10%) were tested here and six weekly replicates of each concentration was applied. The different kaolin concentrations and seasonal variations resulted in a quadratic response of the leaf SPAD reading during both daily evaluation periods. KBPF applications resulted in a quadratic response of photochemical efficiency in the morning period, and an increasing specific leaf weight linear response, and during the dry season, the different kaolin concentrations resulted in a bud length quadratic response. The results indicated that the kaolin application maintained the production and yield index statistically equal between weekly KBPF applications, improving photochemical efficiency, leaf thickness, SPAD reading, and bud length. The use of KBPF could reduce the intervals between collections of mini-cuttings and increase nursery yields in environments that present high temperatures.

We used the cotyledons and cotyledonary nodes of Toona ciliata (Chinese mahogany) as explants to examine callus and adventitious shoot induction when exposed to different ratios of hormones. We also investigated the effects of seedling age, inoculation method, and genotype on the efficient regeneration of T. ciliata. The results showed that different genotypes exhibited significantly different callus induction efficiency. The cotyledons and cotyledonary nodes of 20-day seedlings inoculated onto MS medium with 0.5 mg/L 6-benzylaminopurine (6-BA), 0.5 mg/L kinetin (KT) and 0.05 mg/L 1-naphthylacetic acid (NAA) achieved a greater regeneration rate than did other concentrations of cytokinin and auxin. The numbers of shoots per cotyledon and cotyledonary node explant were 7.33 and 6.67. The optimal inoculation method for cotyledons was that the distal end of the explants was placed in contact with the medium. The optimal adventitious shoot differentiation medium for cotyledon explants was MS medium containing 0.3 mg/L 6-BA and 0.2 mg/L NAA, producing a 3.4 cm height of shoot on average. This study established an efficient regeneration system for T. ciliata with cotyledons and cotyledonary nodes as explants.

Microtubules and their regulatory proteins are involved in the regulation of plant cell morphology. SPIRAL1 (SPR1), a plant-specific microtubule-binding protein, is critical in regulating the anisotropic growth of plant cells. Our previous study showed that overexpressed Salix SmSPR1 genes in Arabidopsis thaliana caused right-handed spiral elongation in etiolated seedlings, but there were no morphological differences between wild-type and transgenic seedlings under varied light conditions. We then studied the transcriptional regulation patterns in transgenic plants engineered with the SmSPR1 gene. Transcriptomic results showed that a large number of differentially expressed genes were involved in plant light signal reception, chlorophyll synthesis and photosystem structure. Eleven gene families with 42 photosynthesis-related genes and 6 light-responsive genes were involved in regulation of cell morphology. Our results showed that these genes in the SmSPR1-ox line were particularly down-regulated under dark conditions. In addition, 33 TFs showed differences between SmSPR1-ox and wild-type lines. Taken together, the transcriptome analysis provides new insight into investigating the molecular mechanisms of light-induced cell morphological changes mediated by the microtubule binding protein SPR1.

WRKY transcription factors are widely distributed in higher plants and play important roles in many biological processes, including stress resistance. The recently published genome sequence of yellowhorn, an oil tree with robust resistance to cold, drought, heat, salt and alkali, provides an excellent opportunity to identify and characterize the entire yellowhorn WRKY protein family and a basis for the study of abiotic stress resistance of WRKY gene family in forest species. In the present comprehensive analysis of WRKY transcription factors in yellowhorn, 65 WRKY genes were identified and defined based on their location on the chromosome. According to their structure and phylogenetic relationships, XsWRKY genes clustered into WRKY groups I–III. Segmental duplication events played a significant role in the expansion of WRKY gene family. Furthermore, transcriptomic data and real-time quantitative PCR analysis showed that expression of XsWRKY genes responding to salt and drought stresses and a hormone treatment. We also determined structures of the encoded proteins, cis-elements of the promoter region, and expression patterns. These results provide a foundation for the study of the biological function of WRKY transcription factors in yellowhorn.

To evaluate and select elite Pinus koraiensis parent combinations and offspring families, 34 full-sib families were evaluated. Variance analysis of tree height, diameter at breast height and volume showed no significant differences among each block, the interaction of block, male and female. The family heritability of all traits were high (> 0.9). Phenotypic and genotypic coefficients of variance of height, diameter at breast height, and volume showed that the phenotypic coefficient of variation of volume in the same combination was higher than height and diameter at breast height, indicating that volume was the main factor determining excellent single plant selection. The female and male trees with the best general combining ability indicated that the optimal parental hybridization was not necessarily the optimal combination. In addition, the least parents of hybrid offspring performance were always relatively poor and should not be selected as hybrid parents. Additionally, we found there was no significant difference among the effects of female and male parents by random modelling, but there were significant differences by fixed modelling. The most significant effect of female- and male interaction, and the selection of better female or male parents in the test parent group should be efficient as well as the results of significant variation among them by fixed modelling. For the evaluated breeding population of P. koraiensis, the backward selection of excellent parent combinations or forward selection of excellent individuals as progeny should be the major breeding strategies.

Understanding the mechanisms and barriers to the restoration of degraded land, especially post agriculture, will help provide protocols on effective ways of restoration into functional ecosystems. One of the barriers in early stages of forest restoration is the arrival and availability of propagules. Seed rain and factors affecting it (i.e., distance to the forest edge, species diversity and surrounding vegetation) were measured in a reforested post-agricultural field and in an adjacent secondary forest. Multivariate glm analysis was used on the seed rain community data and univariate lm analysis on the most abundant seed captured (i.e., Schima wallichii (DC.) Korth.). After 8 months of seed rain collection, there was a total of 3596 seeds from eight tree species. Seeds were more abundant and more diverse in the secondary forest (74.9%, 8 species) compared to the reforested field (24.1%, 2 species). There was a limitation on seed dispersal in reforested field from the adjacent forest. The abundance of S. wallichii seeds determined by the dominance of adult trees (136 trees/ha in the forest and 115 trees/ha in the reforested field). Our study suggests, that after 7 years of planting, the reforested field has received limited seed rain and has not yet recovered.

Evidence-based selective cutting at prescribed intervals as part of good forest management can enhance the carbon sequestration capacity of the forest. The effect of forest management on carbon sequestration has, however, not been quantified. Thus, carbon content of various organs was measured for 323 tree species, 247 shrub species, and 233 herb species in seven temperate coniferous and broad-leaved mixed forests that were subjected to selective cutting with restoration durations of 100, 55, 45, 36, 25, 14, and 6 years to explore dynamic changes in carbon storage. The results showed that biomass carbon allocation in different organs followed a pattern: trunk > root > branch > leaf for all forests. With longer restoration durations, more carbon accumulated in different organs and in soils. Interestingly, when the restoration duration exceeded 50 years, carbon storage in ecosystem was larger than that in primary forests with 100-year cutting intervals, suggesting that a reasonable selective cutting interval can increase forest carbon sequestration. Mean diameter at breast height (DBH) and forest carbon storage were significantly positively correlated, and carbon storage of selectively cut forests exceeded that of primary forests when the stand mean DBH exceeded 15.66 cm. Therefore, mean DBH of forests can be an indicator for combining sustainable forest management and forest carbon sequestration. Additionally, the classic coefficients of 0.45 and 0.50 used to estimate carbon sequestration underestimated values by 2.65% and overestimated by 8.16%, respectively, in comparison with the measured carbon content from different plant organs.

Teak (Tectona grandis L.f.) plantations are increasingly being established in tropical regions to meet a rising demand for its highly valued timber. Teak plantations have been established in the Atlantic Coastal Plain region of Colombia, a region climatically suitable for teak growth by having a monsoon climate with a unimodal precipitation pattern. Tree diameter at breast height (DBH, 1.3 m above ground) and mean top height, periodically measured over a 17-year period in 44 permanent sampling plots of size 0.06 and 0.10 ha, were used in this study. A stochastic differential equation (SDE), along with a Bertalanffy–Richards-type height growth model, was used to model and estimate top height growth of teak plantations in Colombia. Environmental noise and height measurement errors were explicitly considered as the main uncertainty sources of mean top height growth. The best model for estimating mean top height, based on statistical performance and biological rationale, had the asymptote defined as a local parameter and the growth rate and shape specified as global parameters. This model outperformed its counterpart that had the growth rate specified as a local parameter and asymptote and shape as global parameters. The selected model also outperformed alternative approaches such as the mixed-effects model, generalized algebraic difference approach, and the dummy variable method. Estimated trajectories for the mean top height of teak in Colombia are biologically sound based on the measured height series and previous studies in Latin America. Results suggest that most of the uncertainty associated with the mean top height growth of teak plantations in Colombia was largely explained by environmental noise. The best estimated model using the SDE approach can be useful for predicting height growth and evaluating site productivity of teak plantations in Colombia and in neighbouring countries with biophysical characteristics similar to those where teak has been planted in Colombia.

Secondary Miombo woodlands and forest plantations occupy increasing areas in Mozambique, the former due to anthropogenic activities. Plantations, mainly species of Eucalyptus and Pinus, are being established on sites previously covered by secondary Miombo woodlands. This affects the evolution, cycle and spatiotemporal patterns of carbon (C) storage and stocks in forest ecosystems. The estimation of C storage, which is indispensable for formulating climate change policies on sequestrating CO₂, requires tools such as biomass models and biomass conversion and expansion factors (BCEF). In Mozambique, these tools are needed for both indigenous forests and plantations. The objective of this study is to fit species-specific allometric biomass models and BCEF for exotic and indigenous tree species. To incorporate efficient inter-species variability, biomass equations were fitted using nonlinear mixed-effects models. All tree component biomass models had good predictability; however, better predictive accuracy and ability was observed for the 2-predictors biomass model with tree height as a second predictor. The majority of the variability in BCEF was explained by the variation in tree species. Miombo species had larger crown biomass per unit of stem diameter and stored larger amounts of biomass per stem volume. However, due to relatively rapid growth, larger stem diameters, heights, and stand density, the plantations stored more biomass per tree and per unit area.

Caatinga is a typical biome of Brazil’s semiarid regions and subject to climate changes. Research is needed on the relation of its features to climate events. This study analyzed the influence of rainfall and its irregularities in open and dense woody Caatinga vegetation. Phenological curves were generated by means of Normalized Difference Vegetation Index (NDVI) time profiles in the Grota do Angico Conservation Unit study area in Sergipe State. Rainfall data from 2000 to 2018 were collected and phenological curves generated using various estimate methods that produced the following variables: [start of season, end of season, peak of season position, length of season, mean growing season and maximum seasonal]. Rainfall showed a standard intra-annual behavior, with inter-annual variations related to irregularities influencing Caatinga response. Dense Caatinga vegetation had higher values of NDVI in all periods, even in anomalous years compared to open Caatinga, in addition to having longer leaf coverage over the year, with an anticipated start and a more extended seasonal end. The analysis of the rainfall regime made it possible to assess its influence on the Caatinga and phenological profiles proved to be fundamental to understand periods of physiological change of open and dense Caatinga. These results indicate that dense Caatinga maintains physiological activity longer, which may be associated with greater moisture maintenance in a semiarid region. In addition, because it has a greater leaf cover for longer periods, the soil may be preserved and maintain its characteristics longer, reducing the effects of desertification. The results may be associated with the type of forest management and conservation in this region. The total or partial suppression of individual remnants of Caatinga should be avoided, since the most open areas have lower photosynthetic capacity, affected to a considerable extent from the effects of adverse climatic conditions. Additionally, open Caatinga has a reduced capacity for regenerating naturally and its use by communities in this semiarid region should be limited.

This study aimed to understand bark thickness variations of Araucaria angustifolia (Bertol.) Kuntze trees growing in natural forest remnants in southern Brazil, and their relationship with quantitative and qualitative attributes. Bark thickness must be accurately estimated in order to determine timber volume stocks. This is an important variable for the sustainable management and conservation of araucaria forests. In spite of its importance and visibility, bark thickness variations have not been evaluated for this key species in southern Brazil. A total of 104 trees were selected, and their qualitative and quantitative attributes such as diameter at breast height (D_BH), height (H), crown base height (C_BH), crown length (C_L), social position (S_P), stoniness (S_T), position on the relief (P_R), vitality (V_T) and branch arrangement (B_A) were measured. The trees were categorized into two groups: red bark or gray bark. Regression analysis and artificial neural networks (ANN) were used for modelling bark thickness. The results indicate that: (1) bark thickness showed good correlation to D_BH, with 0.76 as coefficient of determination (R ²), 0.540 as Mean Absolute Error (M_AE) and 22.4 root-mean-square error in percentage (R_MSE%); (2) the trend changed according to bark colour, with significant differences for the intersection (

– Pr > F: p = 0.0124) and slope (

{\beta }_1

\documentclass[12pt]{minimal}\usepackage{amsmath}\usepackage{wasysym}\usepackage{amsfonts}\usepackage{amssymb}\usepackage{amsbsy}\usepackage{mathrsfs}\usepackage{upgreek}\setlength{\oddsidemargin}{-69pt}\begin{document}$$ \beta_{1} $$\end{document}

– Pr > F: p = 0.0126) of bark thickness curves between groups; (3) the highest correlation of bark thickness was found with: D_BH (ρ = 0.88), H (ρ = 0.58), C_BH (ρ = 0.46), S_P (ρ = − 0.52), and B_A (ρ = − 0.32); (4) modelling with ANN confirmed high adjustment (R ² = 0.99) and accuracy (R_MSE% = 3.0) of the estimates. ANN is an efficient and robust technique for the modelling of various qualitative and quantitative attributes commonly used in forest mensuration. The effective use of ANN to estimate araucaria bark in natural forests reinforces its potential, besides the possibility of application for other forest species.

Numerous amphibian species occupy microhabitats with buffered thermal and moisture conditions, typically under forest canopies. Here, we assessed whether the insular endemic Salamandra corsica also uses this type of habitat, which could have important implications for its conservation. We used data loggers to record the air temperature and air humidity at 4 h intervals over a period of 2 years, at 13 stations with a confirmed presence of S. corsica. These data were compared with those recorded at Corsican weather stations and those generated by a climate model (WorldClim 2). The weather station data showed significant deviations from the probe data, by an average of − 1.26 °C (minimum temperature), + 2.61 °C (maximum temperature), and − 0.04% (relative humidity). Similarly, the WorldClim 2 data showed significant deviations from the probe data, by an average of − 2.49 °C (minimum temperature) and + 1.69 °C (maximum temperature). These discrepancies reflect the use of densely vegetated and topographically complex habitats by S. corsica, which reduce temperature fluctuations. Overall, our results highlight the importance of natural vegetal cover in the conservation of populations of this endemic salamander.

Wild plants represent relatively unexplored resource of high economic potential, especially as an alternative to developing new crops and, even more relevant, for improving existing crops and contributing to nutrition and health. The wild species Malpighia mexicana (manzanita) has a wide tradition of food, medicinal and ornamental use in Mexico. It is part of the American-origin group of tropical shrubs that produce edible red fruits, such as Acerola, which is considered the most important natural source of vitamin C in the world. Given the role played by M. mexicana in Mexico, and particularly in Barranca del Río Santiago (Santiago River Canyon), we modelled its potential distribution in both geographical areas. We used species’ records from databases, local herbaria and records collected by the authors as well as climatic variables representing long term average, variability and extreme conditions of temperature and precipitation. To fit the models we used the modelling algorithm Maxent and selected an adequate configuration by testing a range of model complexity settings. The results indicate a clear species preference for warm-dry tropical forest, most extensively in the Balsas river depression and the central valleys of Oaxaca. The probability of the species presence in the western region was also high, although the probability was also high for smaller surface areas, such as the region of Santiago river canyons, which are covered by warm-dry tropical forests.

Stocking and structural composition of a deciduous broad-leaved forest were determined to predict coarse woody debris quantity by quantifying the empirical relationships between these two attributes. The most ecologically significant families by stem density were Salicaceae, Betulaceae, Fagaceae, and Aceraceae. Populus davidiana was the most dominant species followed by Betula dahurica, Quercus mongolica, and Acer mono. The four species accounted for 69.5% of total stems. Numerous small-diameter species characterized the coarse woody debris showing a reversed J-shaped distribution. The coarse debris of P. davidiana, B. dahurica, and Q. mongolica mainly comprised the 10–20 cm size class, whereas A. mono debris was mainly in the 5–10 cm size class. The spatial patterns of different size classes of coarse woody debris were analyzed using the g-function to determine the size of the tree at its death. The results indicate that the spatial patterns at the 0–50 m scale shifted gradually from an aggregated to a random pattern. For some species, the larger coarse debris might change from an aggregated to a random distribution more easily. Given the importance of coarse woody debris in forest ecosystems, its composition and patterns can improve understanding of community structure and dynamics. The aggregation pattern might be due to density dependence and self-thinning effects, as well as by succession and mortality. The four dominant species across the different size classes showed distinct aggregated distribution features at different spatial scales. This suggests a correlation between the dominant species population, size class, and aggregated distribution of coarse woody debris.

The Araliaceae family consists of numerous species of medical plants of significant value as non-wood forest products. To conserve and culture these plants in natural forest stands is an important undertaking which should be implemented according to the relationship between forest structure and understory population. In this study, thirty-five plots were established in natural Aralia elata stands. Taller individual and denser populations were found in the northern and in the eastern regions, respectively. Both population densities and individual leaf weight increased along longitude. In contrast, their relationship with elevation and DBH were negative. Along with the altitude gradient, both height and root-collar diameter increased but population density declined. Root-collar diameter and population density decreased with latitude and DBH, respectively. Overall, dominant trees unlikely enforced strong disturbance to the development of understory A. elata populations unless concerning some specific topographic factors.

Tropical forest cover change along with increasing fragmentation has detrimental effects on the global biodiversity. In the current study change in both forest cover and fragmentation of Koraput district have been assessed in the past three decades (1987 − 2017) and future decade (2017 − 2027), which has been modelled using logistic regression showing a gradual decrease in the forest cover and increase in fragmentation. The long term deforestation rates from 1987 to 2017 (current period) and from 1987 to 2027 (predicted period) were found to be -0.018 and -0.012, respectively. Out of the total geographical area, 2027 number of grids (1 km²) out of 8856 grids were found to have shown extinction of forest in the study period. The conversion of forested lands into other land uses has been one of the major causes of deforestation in Koraput, especially because of the increasing mining activities and establishment of three major industries namely National Aluminium Company (NALCO), Damanjodi, Hindustan Aeronautics Limited (HAL), Sunabeda and Ballarpur Industries Limited (BILT). The forest fragmentation reveals a negative trend, recording highest conversion from large core fragments to edge (191.33 km²) and the predicted period has also shown the same trend of negative change, which poses serious danger to the structure of the forests. Out of all the landscape matrices calculated, number of patches will increase to 214 in 2027 from 93 in 1987. In the test between geographically weighted regression (GWR) and ordinary least square regression (OLS), GWR was the better fit model for drawing a spatial relationship between forest cover and fragmentation changes. The study confirmed that the forest cover change has impacted the forest fragmentation in the study area. The programmes like REDD + should be implemented along with the experiences of Community Forest Management and the joint forest management should be intensified at community level in order to develop better management practices to conserve habitats in biodiversity rich areas.

Temperatures of sandy podzols of middle taiga pine forests with moss and lichen ground cover were analyzed which had been exposed to ground fires of low to medium intensity. In general, temperatures in lichen and moss plots of the pine forests under study, are close to each similar, but in the first year after a fire a noticeable contrast was observed. The reasons are an increase in the amplitude of daily temperatures on the soil surface and stronger heating of upper mineral layers. Temperatures in the mineral layer with depths up to 30 cm depend on the thickness of the forest floor. Analysis of the results show that the duration of post-fire effects in pine forests with sandy podzols is determined by a number of factors: the intensity of the fire, the degree of erosion of the ground cover and litter, and the recovery rate of these components.

Fuel moisture content is one of the important factors that determine ignition probability and fire behaviour in forest ecosystems. In this study, ignition and fire spread moisture content thresholds of 40 dead fuel were performed in laboratory experiments, with a focus on the source of ignition and wind speed. Variability in fuel moisture content at time of ignition and during fire spread was observed for different fuels. Matches were more efficient to result in ignition and spread fire with high values of fuel moisture content compared to the use of cigarette butts. Some fuels did not ignite at 15% moisture content, whereas others ignited at 40% moisture content and fire spread at 38% moisture content in the case of matches, or ignited at 27% moisture content and spread fire at 25% moisture content using cigarette butts. A two-way ANOVA showed that both the source of ignition and the wind speed affected ignition and fire spread threshold significantly, but there was no interaction between these factors. The relationship between ignition and fire spread was strong, with R² = 98% for cigarette butts, and 92% for matches. Further information is needed, especially on the density of fuels, fuel proportion (case of mixed fuels), fuel age, and fuel combustibility.

Several indices and simple empirical models and ratios of single band from pre- and post-fire Landsat images have been developed to estimate and/or map burn severity. However, these models and indices are usually site-, time- and vegetation-dependent and their applications are limited. The Daxing’an Mountains range has the largest forested area in China and is prone to wildfires. Whether or not the existing models can effectively characterize the burn severity over a large region is unclear. In this study, we used the orthogonal signal correction method based on partial least squares regression (PLSR) to select those variables that better interpret the variance of burn severity. A new index and other commonly used indices were used to construct a new, multivariate PLSR model which was compared with the popular single variable models, according to three assessment indices: relative root mean square error (RMSE%), relative bias (RE%) and Nash–Sutcliffe efficiency (NSE%). The results indicate that the multivariate PLSR model performed better than the other single variable models with higher NSE% (68.2% vs. 67.8%) and less RE% (3.7% vs. − 8.7%), while achieving almost the same RMSE%. We also discuss the spectral characteristics of the four selected variables for constructing the multivariate PLSR model and their correlation with the field burn severity data. The new model developed from this study should help to better understand the patterns of forest burn severity and assist in vegetation restoration efforts in the region.

To better manage wildfires and plantations in Kurdistan, native tree species commonly used in planting and reviving forests such as Quercus brantii Lindl., Q. infectoria Olivier, Q. libani Olivier, Pistachio atlantica Desf., Fraxinus rotundifolia Vahl, and Robinia pseudoacacia L. were evaluated and compared in terms of fire sensitivity and fire resistance. To determine fire sensitivity, indices such as the flammability index, ignition time, flame durability, moisture content, carbonized surface, mass reduction, bulk density, as well as dry weight of wood, bark, and leaves were used. The data were subjected to ANOVA. The means obtained, after examining homogeneity or heterogeneity of the variances, were compared using parametric and nonparametric comparison tests. There was a significant difference at the level of 5%. Based on the analysis of these indices, the species could be divided into three groups: species sensitive to fire such as Robinia pseudoacacia, species moderately sensitive to fire such as F. rotundifolia, and species relatively resistant to fire, including Q. brantii, Q. libani, Q. infectoria, and P. atlantica.

Studying diurnal variation in the moisture content of fine forest fuel (FFMC) is key to understanding forest fire prevention. This study established models for predicting the diurnal mean, maximum, and minimum FFMC in a boreal forest in China using the relationship between FFMC and meteorological variables. A spline interpolation function is proposed for describing diurnal variations in FFMC. After 1 day with a 1 h field measurement data testing, the results indicate that the accuracy of the sunny slope model was 100% and 84% when the absolute error was < 3% and < 10%, respectively, whereas the accuracy of the shady slope model was 72% and 76% when the absolute error was < 3% and < 10%, respectively. The results show that sunny slope and shady slope models can predict and describe diurnal variations in fine fuel moisture content, and provide a basis for forest fire danger prediction in boreal forest ecosystems in China.

We investigated the arbuscular mycorrhizal fungi (AMF) status of ten nurseries suitable for restoration of dry evergreen Afromontane forests in Ethiopia. We quantified AMF root colonization (RC) and spore abundance (SA) in seedlings of nine native tree species namely Acacia abyssinica Hochst. ex Benth., Cordia africana Lam., Dovyalis abyssinica (A. Rich.) Warb., Hagenia abyssinica J.F. Gmel., Juniperus procera Hochst. ex Endl., Millettia ferruginea (Hochst.) Baker, Olea europaea L. subsp. cuspidata (Wall. ex G. Don) Cif., Podocarpus falcatus (Thunb.) R. Br. ex Mirb. and Prunus africana (Hook. f.) Kalkman. We used the ink and vinegar method to stain AMF in roots. RC levels ranged from 8.00 to  99.67% and were generally higher than the RC levels reported from other similar nurseries in Ethiopia. SA levels ranged from 1 to  25 spores g⁻¹ and were comparable with some reports from the field in Ethiopia but they were lower than levels reported by another similar study. RC was more affected by host species than nursery location, while the reverse was true for SA. The results also showed that nursery management could improve AMF status among seedlings. When all nursery tree species were considered, RC and SA levels were unrelated. No strong correlation existed between the nursery management variables considered and RC or SA. However, considering C. africana, J. procera and P. falcatus separately, RC-age (r _s = 0.829, P = 0.042) correlation for O. europaea and RC-pot diameter (r _s = 0.820, P = 0.046), RC-pot volume (r _s = 0.928, P = 0.008) and SA-age (r _s = 0.943, P = 0.005) correlations for C. africana, were significant, strong and positive. Generally, most of the tree species and particularly, early-mid successional tree species had sufficient AMF inoculum. Hence, only the mid-late successional tree species; J. procera, P. falcatus, and P. africana may require AMF inoculation, preferably, during filed planting. Based on our results, age and pot volume were identified to be important variables potentially affecting RC and SA. To better understand the effects of these and other nursery management variables, additional study is required. We demonstrated for the first time that black Hero ink is suitable for staining root AMF and can be used in future AMF research.

The aim of this work was to evaluate arbuscular mycorrhizal (AM) fungi as soil indicators and the mycorrhization of native and exotic tree species planted in the Acaraú basin, a transition area from the coast to the Brazilian semiarid region. Plots with 6-year-old trees of four native and three non-native species as well as one non-forested area were evaluated in terms of the diversity of AM fungi in the mycorrhizosphere and the root colonization by AM and ectomycorrhizal (EcM) fungi. Twenty-four AM fungi were identified; Claroideoglomus etunicatum, Glomus sinuosum, Paraglomus albidum, Acaulospora laevis, and Acaulospora brasiliensis were abundant in the forest soil. Diversity, dominance, evenness and richness indices of AM fungi were higher in plots with native trees. All root samples were colonized by AM fungi and only Anadenanthera colubrina, Acacia mangium, Casuarina equisetifolia and Eucalyptus urophylla formed associations with EcM fungi. Acaulospora morphotypes served as soil indicators for coverings with the native species Astronium fraxinifolium and Colubrina glandulosa. Exotic species may favor the proliferation of rarer AM fungi. These fungi–plant relationships may be important in the management of forest systems, and the evidence with mycorrhizal associations allows the inclusion of Brazilian species in tropical reforestation.

The decay rate of standing Korean pine (Pinus koraiensis) in natural forests can be as high as 50% and is likely influenced by the soil properties and nutrient and water status of the site. To clarify the relationship between the severity of tree decay and soil properties in order to prevent decay in a natural mixed forest in the Xiaoxing’an Mountains, wood strength of standing trees was nondestructively assessed, and the severity of decay of extracted wood cores was quantified based on differences in mass between two decayed increment cores extracted at breast height and an intact increment core near the decayed ones. Soil samples from the critical root zone (non-rhizosphere) of each tree were analyzed for chemical properties and microbial composition. The abundance of chemical elements (especially total N and K) and the species richness of soil microbes increased as decay severity increased. Fungal number (FN) and actinomycetes number (AN) were related to decay severity (R ² = 0.504). Bacterial number (BN) was higher than FN or AN, but had a minor effect on tree decay. Path analysis showed BN might indirectly inhibit decay by affecting FN. Decay severity was not significantly correlated with either soil fungal or bacterial diversity. These results suggest that forest managers need to monitor levels of fungi and total N and total K levels to reduce the decay of Korean pine.

To examine changes in surface soil quality over time in Populus ×  xiaohei shelterbelts, we collected soil samples from five shelterbelts of different ages and also from former cropland left fallow for 25 years. Twenty-one surface soil (0–20 cm) properties were measured, and variation in soil quality was assessed using one-way ANOVAs and multiple comparison tests. Based on this analysis, 16 soil indexes were used in a model evaluating soil quality, with each index given weight as determined by the correlation coefficient. Compared with the control, the post-mature forest had greater soil moisture content but lower bulk density (P < 0.05). The mature forest also had higher soil pH, total organic carbon, alkali-hydrolyzed nitrogen, available phosphorus, and biomass nitrogen content, but reduced nitrate-nitrogen and total phosphorus content than the control (P < 0.05). Total porosity was highly positively correlated with aeration, nitrate-nitrogen, alkali-hydrolyzed nitrogen, available phosphorus, microbial biomass carbon and microbial biomass nitrogen. Soil total organic carbon, ammonium nitrogen, nitrate-nitrogen, alkali-hydrolyzed nitrogen, total nitrogen, available phosphorus, microbial biomass carbon and microbial biomass nitrogen were all strongly correlated. In the soil quality evaluation model, total organic carbon was assigned the highest weight and total potassium content the lowest. The soil quality index was lowest in the near-mature forest and greatest in the post-mature forest. Generally, soil quality in Populus ×  xiaohei shelterbelts varied with age and was higher in the 10–20 cm versus 0–10 cm soil layer. After a single forest generation, surface soil quality was significantly improved.

A new species of Zanclognatha Lederer, 1857 of the family Erebidae, Z. querciella sp.n., one species of Family Erebidea, Asota egens (Walker, 1854) and two species of Family Noctuidae: Meganephria retinea Gyulai and Ronkay, 1999 and Amphipyra subrigua Bremer and Grey, 1853, are reported for the first time from Korea. In addition, larval feeding habits with their host plants for three species are newly recognized from Korea. Illustration of adults, larvae for Zanclognatha querciella and Meganephria retinea, and the genitalia of male or female for all species are provided.

To study the effect of manganese exposure on the herbivorous insect Lymantria dispar asiatica, fourth-instar larvae were fed a MnCl₂-amended diet (LdMn) for 84 h (0.40 mmol MnCl₂/g diet). Larvae were weighed before and after the diet administration to assess larval gain in mass under manganese exposure. The whole bodies of half of the survivors were ground in liquid nitrogen for measuring enzyme activities and total antioxidant capacity (T-AOC). The intestinal tracts of the remaining survivors were collected and immediately frozen in liquid nitrogen for 16S rDNA sequencing of gut microbiota. Larvae under manganese stress lost significant mass (p < 0.05). The activities of digestive and antioxidant enzymes and T-AOC, but not trehalase and polyphenol oxidase, were significantly higher after Mn exposure, (p < 0.05). A Venn diagram illustrated that the gut microbial OTU composition in the larvae also changed. Community pies and correlation heatmaps also showed different relative abundances of gut microbes. In other words, species quantity and relative abundance of gut microbes agreed with PCoA visualization and indicated that the gut microbial community in L. dispar asiatica larvae differed significantly between control and LdMn. Functional classification also suggested that exposure to manganese stress significantly decreased gut microbial coenzyme transport and metabolism in L. dispar asiatica larvae. These results further our understanding about stress response of L. dispar asiatica larvae.

Odontotermes formosanus (Shiraki), a black-winged subterranean termite, is a common forest pest. A red pigment-producing bacterial strain isolated from the termite was identified as Serratia marcescens and named SM1. A bioassay of SM1 on O. formosanus show that the LD₅₀ ranged from 1.77 × 10⁴ to 10.82 × 10⁴ cells/termite over 21–39 h. Three biological control agents, Beauveria bassiana (2 × 10¹⁰ cells/mL), Metarhizium anisopliae (1 × 10¹⁰ cells/mL) and Bacillus thuringiensis (1.6 × 10⁸ IU/mL), were used for an O. formosanus bioassay. The results show that the insecticidal effect of B. bassiana was stronger than that of M. anisopliae. In addition, two mixtures were obtained by combining B. bassiana (2 × 10¹⁰ cells/mL) with SM1 (1.5 × 10¹⁰ cells/mL), and M. anisopliae (1 × 10¹⁰ cells/mL) with S. marcescens (SM1) (1.5 × 10¹⁰ cells/mL) in equal volumes. The results show that B. bassiana and SM1 was less effective than SM1 alone. However, the insecticidal effect of M. anisopliae and SM1 was better than that of M. anisopliae or SM1 individually. These studies provide an important contribution for termite biocontrol.

This study investigates the potential of native biocontrol agents (BCAs) as controls against Ganoderma lucidum causing root rot mortality in Indian mesquite. The disease is prevalent in sandy soils where trees grow under rainfed conditions. In addition, a beetle namely Acanthophorus serraticornis damages the roots, resulting in increasing vulnerability of the host thereby allowing easy of the pathogen. In dual culture tests, Ganoderma infected cowpea root bit experiment and compatibility with insecticides revealed that the three BCAs (Trichoderma longibrachiatum, T. harzianum, and Aspergillus nidulans) significantly inhibited G. lucidum mycelial growth. The highest mycelial growth inhibition (47.6%) was recorded after 96 h followed by 39.8% and 29.3% at 72 and 48 h, respectively, by T. longibrachium. Cell free filtrates of T. longibrachiatum, T. harzianum, and A. nidulans were superior in inhibiting mycelium growth. A low concentration (3 ml) of T. longibrachiatum was more effective in inhibiting mycelium growth compared to other BCAs. Both Prosopis juliflora compost and onion residue compost amendments as food substrates favored the growth of these BCAs, which ultimately reduced the viability of Ganoderma-colonized root bits of cowpea. Studies on compatibility between insecticides and BCAs suggests that T. longibrachiatum, harzianum and A. nidulans can be combined with phorate or chloropyriphos (both organophosphates) at variable concentrations if amended together for partially infected trees, or as a prophylactic measure in healthy trees. These studies demonstrate that there is considerable opportunity for using native BCAs against G. lucidum in managing root rot disease.

Pine wood nematode (Bursaphelenchus xylophilus), one of the most destructive invasive species, has caused extremely serious economic, ecological and social losses in many countries throughout the world. Since the high reproductive rate of B. xylophilus PWN is the main cause of rapid death of its pine hosts (Pinus spp.), understanding the reproductive and population biology and the ecology of this nmatode are of great importance. This study mainly focused on analyzing the mating process and population structure under different combinations of sex ratios for mating. Reproductive efficiency of B. xylophilus peaked when the sex ratio (female to male) was 3.4:1. Phases of the mating process for the different sex-ratio combinations indicated that B. xylophilus had evolved alternative reproductive strategies to cope with complex copulating conditions to obtain a suitable population structure for further propagation. This research provides fundamental information on the mechanism that is responsible for the rapid population growth of B. xylophilus.

African mahogany, Khaya grandifoliola C. DC., is the most planted mahogany species in Brazil, and became the choice species when plantations of Brazilian mahogany, Swietenia macrophyla King became unsustainable due to their susceptibility to the shoot borer Hypsipyla grandella Zeller. This study evaluated plantation growth and the occurrence of cankers associated with Ectomyelois muriscis Dyar larvae. Surveys recorded plantation volume, survival, and canker incidence of a plantation established in 2010 at 6 m × 5.5 m spacing. Larvae were collected and reared on canker bark fragments until final adult stage. Cankers were frequently associated with Ectomyelois muriscis larvae. The average incidence of the moth (2.9%) was not a significant concern, however, an extreme incidence of 45% would indicate that management strategies should be developed. This is the first report of Ectomyelois muriscis attacking the bark of Khaya grandifoliola in the Cerrado biome.

Pine wilt disease, caused by Bursaphelenchus xylophilus and Bursaphelenchus mucnatus, is a serious quarantined disease. Arboreal nematode-trapping fungi of Pinus spp. are effective predators on nematodes and have strong host adaptability. The development of these fungal resources may be an effective way to control pine wood nematodes. We collected 515 samples of pine wilt disease from the areas of Ninghai City (Zhejiang province), Shuangbai County (Yunnan province), and Daxing’anling (Heilongjiang province), China. Through isolation, culture and identification, 6 species of nematode-trapping fungi (Arthrobotrys cladodesr, A. oligospora, A. musiformis, A. dendroides, Dactylellina ellipsospora, Monacrosporium thaumasium) were identified for predation against B. xylophilus, and 9 species (Arthrobotrys dactyloides, A. cladodesr A. oligospora A. dendroides, Dactylellina ellipsospora, Dactylella asthenopaga, D. leptospora, Arthrobotrys superba, Monacrosporium drechseri) were identified for predation against B. mucnatus. This study provides information in the classification of arboreal predator nematodes and provides an important basis for future biological control of pine wood nematodes.

Using the advantages of web crawlers in data collection and distributed storage technologies, we accessed to a wealth of forestry-related data. Combined with the mature big data technology at its present stage, Hadoop’s distributed system was selected to solve the storage problem of massive forestry big data and the memory-based Spark computing framework to realize real-time and fast processing of data. The forestry data contains a wealth of information, and mining this information is of great significance for guiding the development of forestry. We conducts co-word and cluster analyses on the keywords of forestry data, extracts the rules hidden in the data, analyzes the research hotspots more accurately, grasps the evolution trend of subject topics, and plays an important role in promoting the research and development of subject areas. The co-word analysis and clustering algorithm have important practical significance for the topic structure, research hotspot or development trend in the field of forestry research. Distributed storage framework and parallel computing have greatly improved the performance of data mining algorithms. Therefore, the forestry big data mining system by big data technology has important practical significance for promoting the development of intelligent forestry.

Based on the analysis of complex terrains and current forest transportation equipment, a forest tracked vehicle prototype LY1352JP was developed. The road model and the virtual prototype of the chassis were constructed using dynamic simulation software RecurDyn. The optimal tension of the vehicle as well as its capabilities for crossing trenches, climbing vertical walls, uphill and downhill slopes were simulated. The simulation results showed that the optimum tension force of the chassis of the vehicle was 63 kN (kilonewton), accounting for 45% of the total vehicle weight. The maximum trench crossing width and vertical obstacle climbing height were 1.35 m and 0.45 m, respectively. The maximum uphill and downhill angles were 50° and 45°, respectively. Tests on the prototype capacity for crossing trenches, and uphill and downhill driving were carried out. The test results were in agreement with the simulation results. A cross-country performance of a fire truck based on the tracked vehicle chassis was conducted in an old-growth forest. Tests verified that the vehicle has a strong forest trafficability performance and can meet the needs for forest transportation.