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  • Open access
  • 96 Reads
Provenances and progenies trial of Mexican spruces (Picea mexicana, Picea martinezii and Picea chihuahuana) in nursery: species susceptible to climatic variation

In Mexico there are three endemic species of Picea, living in relict populations and they are listed as “Endangered” on the Red List of the IUCN. P. mexicana has only three locations, above of 3,000 m of altitude. P. martinezii has four populations between 1,800 and 2,500 m and P. chihuahuana has been found in 40 locations between 2,311 and 2,730 m; The Mexican spruces distribution is fragmented in isolated populations, which could lead to phenological, morphological and genetic differentiation partially caused by local adaptation to different soil types and climate changes. Therefore, it is important to identify the main factors accounting for such adaptation, which would be helpful in assisted migration programs as an option to ex situ conservation. In that sense, in this study we examined the effect that the edaphology and climatic variables of different populations have on the growth and survival of each Picea species seedlings in equal nursery condition, assuming that such response on growth could be taken as a proxy of the adaptation or the genetic differentiation among populations.

Methods. Considering 22 climatic and 27 edaphology variables from each location we established a provenances trial, in a nursery located at El Salto, Durango; México, where we measured the growth in diameter and height of 5,641 seedlings, during 12 months and the survival. Applying a cluster analysis and a Calculate Pairwise Multiple Comparisons of Mean Rank Sums to calculated differences among locations. The individual heritability (h2i) and the means of family (h2f) were also evaluated. We used the Spearman´s correlation test to analyze the relationships between growth traits and the climatic an edaphology variables from each location.

Results. The cluster analysis revealed three populations groups. The Calculate Pairwise Multiple Comparisons of Mean Rank Sums showed significant differences in the genetic quantitative traits between locations within each species. The genetic control on the growth traits was high and correlations between genetic quantitative values and climatic factors were detected.

  • Open access
  • 42 Reads
Forest Carbon in Climate Change Supermarket: Is India Prepared to Sail?

Market-based mechanisms have evolved to internalize the negative externalities of excessive greenhouse gas emissions. Several market-based instruments have been developed to facilitate effective mitigation of climate change through voluntary and regulatory measures. A number of such instruments are expected to hit the carbon markets with the take-off of the new global deal on climate change- The Paris Agreement, along with other planned and potential regional, national and sub-national regimes to address the problem of climate change. With the possibility of inter-linking the carbon market segments in times to come, we see a complex picture of the existing carbon markets turning into a future supermarket. India is a leading country in terms of registered clean development mechanism (CDM) projects in afforestation and reforestation (AR) sector, however, the basket of projects developed so far is not versatile in terms of coverage of carbon pools, greenhouse gases and intervention types. We explore the potential of India becoming a leading party in forest-based carbon supermarkets in the backdrop of: (i) existing capacities, such as robust monitoring set-up, (ii) commitments of forest restoration, such as forest-related goal in nationally determined contributions, (iii) actions taken, such as Green India Mission, and (iv) the enabling conditions, such as CAMPA and Forest Rights Act. We discuss the extent to which the institutional set-up in the country is prepared for taking up the new and emerging market-based mechanisms in carbon forestry. We triangulated existing literature, on-ground observations from two registered AR CDM projects being implemented in Kashi and Mahoba forest divisions in the Indian state of Uttar Pradesh, and the expert interviews. We list out the constraints and gaps in India’s readiness to identify and embrace the opportunity of being a top player in the upcoming climate change supermarket in the context of forest restoration.

  • Open access
  • 98 Reads
Using Thermal Neutron Imaging in Forest Products Research

Neutron imaging is a non-destructive evaluation technique with enhanced hydrogen sensitivity that allows researchers to monitor water content and transport in materials. In lignocellulosic research, this technique has typically been used to measure changes in moisture content, water transport and even local changes in the density of wood. Yet, studies looking into the combined effects of moisture-uptake, chemical modifications and thermal degradation are still lacking. This is perhaps due to the inherent limited availability of these instruments and their lesser spatial resolution compared to x-ray imaging. While recent advances in detector technology and neutron production have led to continued improvements in both instrument availability and spatial resolution, the technique remains underutilized in forests products research. In this talk, we will provide an overview of the basics of neutron imaging of wood and examples of imaging using thermal neutrons produced via a compact neutron source instead of a research nuclear reactor. We will highlight studies taking advantage of the technique’s sensitivity to hydrogen content to study the effects of thermal degradation and/or chemical modifications on wood and wood-polymer composites.

  • Open access
  • 66 Reads
Could fire severity promotes the biosynthesis of bioactive compounds as a strategy to enhance the plant survival?

Fire causes effects on diverse aspects of plant functioning and development, many of them linked to survival. However, the response of native vegetation to this disturbance possibly reveals a plant strategy to tolerate fire linked to the biosynthesis of compounds like chlorophylls and secondary metabolites. The aim of this study was to evaluate whether fire severity could promote the biochemical tolerance to fire by influencing the biosynthesis of chemical compounds. To test this, we exposed six woody species from the Chaco region to an experimental burn of medium severity at fire season ending in the study area. In this burn, we established individual plots for each plant. Fire severity was estimated visually as the burnt biomass of each plant, which was considered as the percentage of the loss of aboveground biomass. Then, the biochemical plant response to fire was studied, through the changes in the concentration of photosynthetic pigments (chlorophyll and carotenoids), and secondary metabolites (phenolic compounds and tannins). The metabolites quantification was carried out by using spectrophotometric methods. As results, a strong correlation was found between the biosynthesis of metabolites in response to fire and the amount of burnt biomass during the experimental burns. This correlation could be considered as an indicator of the burnt plant response to stress. In our results, shrubby species showed both the higher amount of burnt biomass and the enhanced biosynthesis of compounds in the resprouts post-fire, which could be related to the capacity of these species to stablish in disturbed environments. Our study provides an insight into the understanding of the plant strategies to fire tolerance and resilience in natural environments.

  • Open access
  • 82 Reads
Correlation between the spectrometric parameters of coniferous seeds and the molecular indicators of seedlings: is it possible to apply it in practice?

Coniferous seeds as an integral part of Forest Reproductive Material (FRM) are a fairly valuable product that is transported by trade operations over long distances. Seed quality determines the rate of reforestation. Improving quality indicators and increasing the competitiveness of forest seeds is one of the promising directions of the many country’s forestry development strategy and an opportunity to integrate into global reforestation initiatives. Based on the direct interaction of biophysical studies of seed spectrometric parameters, implementation of their genotype in different environmental conditions, biometric studies of seedling growth and development and genetic conditioning of these components, it is possible to develop and test a comprehensive concept for obtaining FRM with high quality indicators. What practical application can be expected? First, it is possible to study genetic variability among the seeds of the studied species using molecular DNA markers to obtain a comprehensive and categorical classification of samples that illustrates the genetic similarity and relationship structure relative to the desired characteristics of seedlings and seeds with high viability rates. Genetic and spectrometric data can be further combined to build a consensus tree of genetic similarity. Second, algorithms can be developed for integrating these parameters in the FRM-Library database to synchronize the quality indicators of forest reproduction material with information processing devices of optoelectronic graders and phenoseeders. Third, methods and algorithms can be developed for optimal selection of technology for coniferous seeds grading of different breeding values will be developed based on data extracted from the FRM-Library database for the production of forest reproductive material, considering various goals and frontiers methods of contemporary forest landscape restoration.

  • Open access
  • 60 Reads
Comparative analysis of microbial communities in adult trees and seedlings of Douglas fir

The composition and complex interaction of microorganisms in forest trees is still not very well understood. However, current studies on cultivated plants indicate that the microbiome can have a significant influence on plant development, vitality and susceptibility to pathogens.

In the project “TreeLAMP”, the composition of the microbial community of ten adult trees and nine seedlings of Douglas fir was characterised in an exploratory study using sequence-based methods. Approximately 9.5 million fungal sequences (ITS1) and approx. 4.3 million bacterial sequences (16S rRNA gene) were generated over all samples by Illumina MiSeq sequencing. In a first step the quality of the sequence data was checked and sequences with low quality were filtered with dada2. The taxonomic classification was carried out with the program kaiju (database NCBI nr+euk).

For the characterisation of the fungal community, between 13,817 and 410,464 sequences per tree sample were analysed. In total 83 fungal species were identified. However, on average 0.5 % of the sequences could not be classified and 48.1 % could not be determined up to species level. The DNA of the bacterial community shows with 899 to 11,807 significantly less sequences per sample. But in comparison 79.4 % of the sequences could be determined up to species level, 15.2 % of the sequences were assigned to at most a genus, and 5.3 % could not be classified. In total 142 bacterial species were identified. In summary, the composition of the fungal and bacterial species community differs, as expected, between adult trees and seedlings. Differences in species composition were also observed within adult trees and seedlings, whereby the bacterial community was generally more heterogeneous than the fungal community.

  • Open access
  • 52 Reads
New data on host range and geographical distribution of Dothistroma needle blight in Ukraine

Serious pine needle disease, Dothistroma needle blight (DNB), caused by Dothistroma septosporum and D. pini was detected in Ukraine in 2004-2005, although D. septosporum was first reported in Ukraine in 1914. The aim of this study was to identify the Dothistroma species present on new hosts in Ukraine using different molecular techniques to increase our understanding of the local distribution of these pathogens. The current situation of Dothistroma needle blight in Ukraine was studied in native, planted pine forests and arboretums. The occurrence and distribution of DNB were studied in 2012–2018 and 480 needle samples were collected from 16 different regions in 96 localities, and the presence of DNB was confirmed in 62 of them. The host range of DNB consisted of 8 pine species including 3 subspecies and 2 spruce species, among them Pinus nigra J.F. Arnold subsp. pallasiana (Lamb.) Holmboe and P.sylvestris L. were the most frequent hosts. Results showed that both D. septosporum and D. pini were present on P. nigra subsp. pallasiana on the same trees and even in the same needles Moreover, D. septosporum was found first in Ukraine on Pinus ponderosa Douglas, Pinus banksiana Lamb and Pinus contorta Douglas in the arboretum as well as Picea pungens Engelm and Picea abies (L.) H. Karst. The suitability for the disease in the different forest types and intensity of the disease are discussed. To sum up, DNB was found in many parts of the country although the disease intensity is low, probably due to the unfavourable climate conditions for DNB development.

  • Open access
  • 141 Reads
Structural diversity of tree stems of Elephant camp natural forest in Omo Forest Reserve

Statement of problem: Tree size diversity is an indicator for biodiversity values of a forest. Microsite conditions of forest determine the survival and growth of tree. However, the contribution of variable habitats to tree size hierarchy and segregation is poorly understood. Variation in size of trees in a population is cause by different mechanisms. Therefore, size distribution and spatial pattern of trees can identify process govern growing resources utilization in the forest. The objective of the study is to determine the structural diversity of tree stems of Elephant Camp natural forest in Omo Forest Reserve.

Methodology: Three and four 0.09ha sample plots were established in Riparian (RF) and Old-growth forests (OF) of Elephant camp, respectively. The tree stems (Dbh≥5cm) were identified to species level and enumerated within each plot and stem density was computed. The diameter-at-breast height (Dbh) was measured with diameter tape. Species diversity was assessed using Shannon-Weiner (H´) and Simpson indices (1-D´) while size inequality was assessed using Gini coefficient (GC), Coefficient of Variation (CV), H´ and I-D´. The performance of single two- and three-parameter Weibull models were evaluated; Kolmogorov-Smirnov (K-S) Chi-Square (χ2), Root Mean Square Error (RMSE), Bias and Coefficient of determination (R2). Data were analysed using descriptive statistics at α0.05.

Results and Conclusion: A total of 27 and 24 tree species were identified in RF and OF, respectively. Stem density of RF was significantly higher than OF. The value of species diversity (H´, 1-D) and Evenness (E´) were higher in OF than RF while richness (Margalef and number of species) was higher in RF than OF. The Dbh were 38.30±21.4 and 42.87±19.2cm in Riparian and Old-growth forests, respectively. Diameter distribution of Riparian and Old-growth forest were positively skewed and expressed exponential pattern. The Elephant Camp is rich in tree species and moderate in tree size inequality. It had good regeneration status with high density of small size and mid-size tree stems.

  • Open access
  • 55 Reads
Influence of Ponsse Gazzelle forwarder passes on the soil environment and soil deformation.

During the harvesting and skidding process, machine runs have a strong influence on the soil environment. The study analyzed the influence of 20 runs of the Ponsse Gazzelle forwarder on the change of soil compactness, moisture and deformation. The research were carried out in Gidle Forest District, located in southern Poland. Analyzed areas was differing in soil type and hydrological conditions. On the investigated forest areas control sections were established for measurements.
The data of changes in soil compactness were gained by using a handheld penetrometer at a depth of 10 and 20 cm. The soil compactnes were measured after each forwarder pass. Soil moisture was also assessed at a depth of 10 and 20 cm before the start of the forwareder operation, and after 20 passes. To obtain data for determining soil deformation UAV were used. Terrain models were created using Agisoft Metashape software. From the generated 3D terrain models, changes in the cross-sections of operational routes were determined.
The data were subjected to statistical analysis to determine the relationship between the rate of changes in soil and terain conditions. The increase of soil compactness was linear on all the examined plots. Statistically significant differences were found in the soil compaction rate.
The average decrease in humidity after 20 forwarder runs on the tested sections was 39%.
Correlation analysis showed a moderate relationship with the extent of soil deformation and the type of soil and the type of forest habitat.

  • Open access
  • 64 Reads
Concept of forest development phases: identification and classification issues

The decision making in forestry and choosing the appropriate silvicultural practices are based on the knowledge about forest development. Usually, forest development is described as a cycle or sequence of phases similar to the development cycles of organisms. The information about the development cycle of unmanaged forest ecosystems is applied and adapted to managed stands to refine the managerial approaches and decision making. Besides, natural forests are more stable and resist pests and diseases better. Thus knowing the mechanisms that lie behind this self-sustainability could help in forest stand management. Assigning a patch of a stand a specific development phase makes it possible to arrive at conclusions about its productivity and making decisions about necessary silvicultural operations. Yet there is no single opinion among the scientists about how many phases the forest’s life cycle has, not to mention that different classifications offer different and sometimes even contradictional criteria to define the current forest development phase for a given subplot. The confusion in terminology for stand structures and stand development phases is also an issue to be considered. Several, the most popular approaches to assigning forest development phases are compared. A short overview of the algorithms used to define the forest development phases is given. There is a lack of a complex approach in the offered algorithms of assigning a subplot to a certain development phase. In particular, soil properties, as well as belowground biomass, are entirely ignored. It is necessary to develop a more comprehensive and detailed approach to defining forest development phases and arranging the diagnostic criteria in a clear and easy-to-use system that could be applied for decision making forestry. Only several studies are currently focused on soil properties and belowground biomass in temperate deciduous forests under different development phases. Although there is still little information on this issue, the data is insufficient and controversial. Our study offers several possible directions to make the forest development phases classifications more elaborate by considering the soil and belowground parameters. They include but are not limited to, quantity, density, humidity, and acidity of forest floor, soil respiration, and content of water-extractable organic matter in the soil.

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