Utility Value Criteria in Selection of Species for Sustainable Reclamation of Silica Mining Area

Silica sand mining in Shankargarh, Prayagraj, India area has led to extensive ecological destruction, environmental degradation and erosion of traditional values in the society. Therefore, an integrated organic and socioeconomic approach is urgently required to bioreclaim degraded mine sites.The most common problems linked with degraded land rehabilitation failures are frequently associated with improper selection of plantation species. Subsistence utility preferences of local people are major acclaimed and convincing reasons in the selection of valuable tree species for Bioreclamation. Socioeconomic Survey were carried out in the nearby villages of Silica mining area to study the existing resources of the area, social structure of the community, dependence on forest and species preferred by the local people. Consequently, a Utility Value Index (UVI) framework was conceptualized, designed and subsequently developed to identify species preferred by the local people and highly valued for supporting their livelihood.

Survey, Identification, and Pathogenicity of Ceratocystis fimbriata Complex Associated with Wilt Disease on Acacia mangium in Malaysia

Ceratocystis wilt disease surveys were conducted in three selected Malaysian Acacia mangium plantations. These completed surveys revealed the occurrence of the wilt disease, with the incidence of infection ranging from 7.5% to 13.6%. Signs of wood-boring insects, bark peeling due to squirrel activity, and pruning wounds were often associated with this disease. The fungus most frequently isolated from the diseased trees was the Ceratocystis fungus. The analysis on the morphological characteristics has identified the fungus as Ceratocystis fimbriata complex. Phylogenetic analysis based on the sequences of the ITS, and concatenated sequences of EF1α-βT regions grouped the isolates within the C. fimbriata sensu stricto, in comparison to other C. fimbriata isolates. Pathogenicity tests were conducted on six to nine-month-old healthy A. mangium seedlings by inoculating these seedlings with eight out of the 16 isolates. The results demonstrated that all the isolates were pathogenic, with mortality beginning as early as two weeks after inoculation. However, an ANOVA test indicated a significant difference between the pathogenicity levels among the fungal isolates. The results also showed that pathogen aggressiveness was not correlated with geographical origin. A host range test was also conducted by using C. fimbriata SSB3 and FRIM1162 isolates against several forest plantation species. The findings suggested that only A. mangium was susceptible to C. fimbriata. The other species remained healthy with no symptoms of infection even after seven weeks of treatment, as compared to the A. mangium species, where between 38 to 60% of the inoculated plants had died. This study provides new information on the status of Ceratocystis wilt disease, especially on the occurrence and effects on A. mangium plantation, by giving insights on how to control and manage this ferocious plant pathogen in the future.

Reducing ecological risk from the impacts of introduced exotic species in forestry industry: Limiting the invasiveness through a management and biological practices in Acacias plantation in Indonesia

Balance benefit of ecological, economic, and social is a part of sustainable forest management. Industrial forest plantation is one of the ecological practices through increasing land cover to provide a good impact for economic and social. Introducing suitable species for industry from out of regions is commonly practiced in the plantation. In Indonesia, some Acacias species have been recognized as major plantation species to meet industrial requirements that are economically feasible, suited to major end-product, high productivity, and fast growth. However, some studies have classified the Acacias as exotic species which potentially show an invasive. Taking into account such invasiveness and anticipating ecological risk, this paper presents some considerations on plantation management and biological practices of the Acacias. Compromises among the reproductive system, growth, and rotation in the plantation management could limit the invasiveness. Besides high stand productivity, results from genetic and breeding could also provide a positive impact to diminish the reproductive process of trees that consequently reduce seeds in the Acacias plantation and limit its invasiveness. It concludes that some considerations and a good understanding of biological factors in plantation management practices could reduce ecological risk from the invasiveness of Acacias, and even it could be used for increasing plantation productivity.

Chromosome-specific polymorphic SSR markers in tropical eucalypt species using low coverage whole genome sequences: systematic characterization and validation

Eucalyptus is one of the major plantation species with wide variety of industrial uses. Polymorphic and informative simple sequence repeats (SSRs) have broad range of applications in genetic analysis. In this study, two individuals of Eucalyptus tereticornis (ET217 and ET86), one individual each from E. camaldulensis (EC17) and E. grandis (EG9) were subjected to whole genome resequencing. Low coverage (10×) genome sequencing was used to find polymorphic SSRs between the individuals. Average number of SSR loci identified was 95,513 and the density of SSRs per Mb was from 157.39 in EG9 to 155.08 in EC17. Among all the SSRs detected, the most abundant repeat motifs were di-nucleotide (59.6%–62.5%), followed by tri- (23.7%–27.2%), tetra- (5.2%–5.6%), penta- (5.0%–5.3%) and hexa-nucleotide (2.7%–2.9%). The predominant SSR motif units were AG/CT and AAG/TTC. Computational genome analysis predicted the SSR length variations between the individuals and identified the gene functions of SSR containing sequences. Selected subset of polymorphic markers was validated in a full-sib family of eucalypts. Additionally, genome-wide characterization of single nucleotide polymorphisms, InDels and transcriptional regulators were carried out. These variations will find their utility in genome-wide association studies as well as understanding of molecular mechanisms involved in key economic traits. The genomic resources generated in this study would provide an impetus to integrate genomics in marker-trait associations and breeding of tropical eucalypts.

Thinning Influences Wood Properties of Plantation-Grown Eucalyptus nitens at Three Sites in Tasmania

Thinning of forestry plantations is a common silviculture practice to increase growth rates and to produce larger dimension logs. The wood properties, basic density and stiffness, are key indicators of the suitability of timber for particular purposes and ultimately determine timber value. The impact of thinning operations on wood properties is, therefore, of considerable interest to forest growers and timber producers. To date, studies examining the impact of thinning on wood properties have produced variable results and understanding of the consistency of the effects of thinning treatments across various sites for important plantation species is limited. Two non-destructive assessment techniques, drilling resistance and acoustic wave velocity, were used to examine the impact of thinning on basic density and stiffness in 19–21-year-old plantation grown Eucalyptus nitens across three sites. Commercial thinning to 300 trees ha−1 decreased the stiffness of standing trees and this effect was consistent across the sites. Reduction in stiffness due to thinning ranged from 3.5% to 11.5%. There was no difference in wood properties between commercially and non-commercially thinned trees to 300 trees ha−1 and no difference in wood properties when thinned to 500 trees ha−1. Basic density was not affected by thinning. The site had significant effects on both basic density and stiffness, which were lowest at the highest precipitation and highest elevation site. The results indicate that wood properties are influenced both by silviculture and site environmental differences. This knowledge can be used for the better management of E. nitens resources for solid wood production.

A Deep Fusion uNet for Mapping Forests at Tree Species Levels with Multi-Temporal High Spatial Resolution Satellite Imagery

It is critical to acquire the information of forest type at the tree species level due to its strong links with various quantitative and qualitative indicators in forest inventories. The efficiency of deep-learning classification models for high spatial resolution (HSR) remote sensing image has been demonstrated with the ongoing development of artificial intelligence technology. However, due to limited statistical separability and complicated circumstances, completely automatic and highly accurate forest type mapping at the tree species level remains a challenge. To deal with the problem, a novel deep fusion uNet model was developed to improve the performance of forest classification refined at the dominant tree species level by combining the beneficial phenological characteristics of the multi-temporal imagery and the powerful features of the deep uNet model. The proposed model was built on a two-branch deep fusion architecture with the deep Res-uNet model functioning as its backbone. Quantitative assessments of China’s Gaofen-2 (GF-2) HSR satellite data revealed that the suggested model delivered a competitive performance in the Wangyedian forest farm, with an overall classification accuracy (OA) of 93.30% and a Kappa coefficient of 0.9229. The studies also yielded good results in the mapping of plantation species such as the Chinese pine and the Larix principis.

REVIEW OF CHARACTERISTICS OF ALNUS GLUTINOSA STANDS QUALITY ACCORDING TO FOREST TYPES AND AGES

Due to the interest in Alnus glutinosa as the plantation species has increasesed in Latvia during last years, a structural unit “LVM Sēklas un stādi” of State Stock Company “Latvijas Valsts Meži” (Latvia’s State Forests) offers to the local market Alnus glutinosa bare root seedlings with an advanced root system obtained from Alnus glutinosa seeds growed in planting such selected seedlings in cutovers and for land reforestation theorectically will allow the land owner to increase the value of forest and the profit from its management. Practically, this prospects should be evaluated from the perspective of forest health.Therefore, the purpose of this study were to: (1) estimate the incidence of heart colouring and stem decay in Alnus glutinosa stands in different forest types and ages, (2) identify and measure heart colouring area /heartwood hard rot stage area diameter and soft rot stage area diameter/ cavity diameter of the stumps, (3) evaluate the relationships between stand species composition (forest types) and Alnus glutinosa stands age on heart colouring/heartwood hard rot stage and soft rot stage/cavity incidence, (4) by analysing the results to work out the recommendations to improve the forest managment in forest stands where Alnus glutinosa stands from plantations are growing.

Mikania micrantha (bitter vine).

M. micrantha is a fast growing vine, native to Central and South America. It was intentionally introduced into a number of countries and has since become a major weed in Southeast Asia and the Pacific and is still extending its range. However, it has not yet been recorded in Africa. Once established, M. micrantha can quickly smother other vegetation, including native trees, plantation species and agricultural crops, killing plants and/or decreasing yield and biodiversity. In Nepal, the vulnerable greater one-horned rhinoceros is under threat as M. micrantha outcompetes plant species on which it browses. Control of this species is difficult as it produces are large number of seed, can readily shoot from runners and suckers and can regenerate from stem fragments. This species has been the target of a biological programme in many countries.

Eucalyptus robusta (swamp mahogany).

E. robusta is a medium to large tree and is capable of rapid early growth in suitable environments. This species has a broad environmental amplitude, and is planted widely outside of Australia in equatorial to cool temperate regions. E. robusta is best known as a plantation species in the Madagascar highlands, but also in the USA (Hawaii, Florida, California) and Central America (Puerto Rico). E. robusta may tolerate adverse conditions and is especially useful on sites subject to prolonged flooding. It is moderately salt-tolerant. This species is often used as a shade tree, an ornamental, in shelter belts and in water catchment rehabilitation. The wood of E. robusta is a good fuel and is commonly used for charcoal production. It is durable and is used in the round for posts and poles. Sawn timber can be used for general construction but requires kiln-seasoning to avoid degradation during drying. It is possible to use E. robusta as a source of pulpwood for paper making but other eucalypts are usually preferred.