scholarly journals Tree Change in Nemoral Spruce Forests of the Central Forest Reserve

Author(s):  
M. Yu. Pukinskaya

The paper discusses changes in forest-forming species in the nemoral spruce forests of the Central Forest Reserve (Tver Region, the Russian Federation). A comparison is made of the characterization of vegetation in the reserve spruce forests, carried out during the first survey of the reserve by Ya. Ya. Alekseev in 1931 (Alekseev, 1935) with the descriptions of vegetation made by the author from 2011 to 2019. It is shown that the coverage of nemoral herbs in the spruce forests of the reserve has increased over the past 90 years. In addition, three types of broadleaf trees (Tilia cordata Mill., Acer platanoides L. and Ulmus scabra Mill.) have greatly increased their abundance in the stand, most notably the linden. In recent decades, the decay of nemoral spruce forests has been taking place in the Central Forest Reserve. The birch-aspenspruce stand is not replenished with spruce renewal but is replaced by linden-maple forests. The vitality of spruce undergrowth is deteriorating. After the decay of a spruce forest, a change of the tree dominants occurs on 74% of the trial plots and the stand continues with a spruce forest on 26%. The largest part of the reserve's nemoral spruce forests arose after major disturbances 100–150 years ago (on the site of burned-out areas, hurricane windblows and cuttings). Old nemoral spruce forests were formed during the period when severe frosts prevented linden and maple from entering the stand. Currently, the coincidence of climate warming with the aging of the spruce stand and the removal of anthropogenic influence contributed to the release of maple and linden from the undergrowth into the stand and change to a spruce-deciduous forest. Under the prevailing climatic conditions, a return to the spruce forest is possible in the event of a burning out or when the climate becomes cold. The nemoral spruce forest is an ecotone type and, depending on conditions, becomes a spruce or broad-leaved forest.

2013 ◽  
Vol 62 (1-6) ◽  
pp. 124-126 ◽  
Author(s):  
Hong-Yu Niu ◽  
Wan-Hui Ye ◽  
Zheng-Feng Wang ◽  
Ying Chen ◽  
Hong-Lin Cao ◽  
...  

Abstract Schima superba is a common dominant tree species in evergreen broad-leaved forest in subtropical China. Despite its multiple usages in wood industry, reforestation and traditional Chinese medicine, its genetic diversity is poorly studied. To help studying its genetic diversity and structure in the future, after microsatellite enrichment and screening, we identified 16 microsatellites in S. superba. These markers showed polymorphism in three populations. The number of alleles per locus ranged from 3 to 32 with a mean of 14. Within populations, the observed and unbiased expected heterozygosities ranged from 0.048 to 0.926 and from 0.048 to 0.949, respectively. The newly developed 16 microsatellites will be useful for investigating the genetic diversity and structure from large scale patterns to fine-scale structures in this species.


2017 ◽  
Vol 7 (3) ◽  
pp. 66-74
Author(s):  
Людмила Иванчина ◽  
Lyudmila Ivanchina ◽  
Сергей Залесов ◽  
Sergey Zalesov ◽  
Евгения Залесова ◽  
...  

Plantions of pleurocarpous moss spruce forest type are dominant in the area of coniferous-deciduous (mixed) forests of the European part of the Russian Federation in Perm region. The problem of drying of spruce forests has aggravated dramatically in recent years. However, among scientists there is no consensus on the causes of the drying of spruce forests, which hinders the development of recommendations on improvement of forest management in spruce forests. In this regard spruce plantations in Perm region are not exceptions. On the basis of acts of forest pathology survey, drying of pleurocarpous moss spruce forest with different composition of forest stands is analyzed. The drying area for the period from 2010 to 2016 at Ocherskoe forestry in Perm region (forest area of coniferous-deciduous (mixed) forests of the European part of the Russian Federation) is mapped to a planted area of pleurocarpous moss spruce forest of different species composition. It was found that there was no drying out spots for the analyzed period in plantings of pleurocarpous moss spruce forest with a mixture of softwood species. As well as stands with admixture of fir and birch are characterized by high resistance. Among the identified drying out spots of spruce the most represented are plantations which contain of spruce, fir and pine (28.1 % of the total area of drying out spots), as well as spruce, fir, pine and birch (22.56 % of the total area of drying out spots). Data on the influence of the composition of the forest on mortality of spruce in the conditions of pleurocarpous moss spruce forest can be used in forming thinnings, as well as creation of forest crops.


2018 ◽  
Vol 37 (11) ◽  
pp. 731-737 ◽  
Author(s):  
P Ramesh ◽  
B Durga Prasad ◽  
KL Narayana

Nowadays, fiber-reinforced composites have gained attention due to their improved potential for replacing the conventional materials in various applications. Kenaf fiber has been widely used as reinforcement in composites over the past few years which is a most attractive alternative due to its rapid growth at different climatic conditions and ensuring low cost; kenaf fiber has gained some attention to replacing the glass fiber composite and making it purely an eco-friendly composite. However, for enhancing its properties in different applications, an appropriate characterization is very important. Hence, many researches have been conducted in recent years, for the characterization of kenaf fiber and its composites. In this paper, a state-of-the-art review of these characterizations is presented.


Forests ◽  
2020 ◽  
Vol 11 (7) ◽  
pp. 778 ◽  
Author(s):  
Tatiana Chernenkova ◽  
Ivan Kotlov ◽  
Nadezhda Belyaeva ◽  
Elena Suslova ◽  
Olga Morozova ◽  
...  

East European forests dominated by Norway spruce (Picea abies (L.) H. Karst.) in the broad-leaved–coniferous zone should be considered as secondary communities formed under the influence of centuries-long activities (logging, fires and planting) and extended outside their natural range. The study raises an issue—how stable is the current state of Norway spruce forests in the center of the Russian plain and what is the effect of silviculture on the forest cover of the large urban agglomeration—the Moscow Region? Current study is based on multidisciplinary research and consequently concerns the age dynamics of spruce plantation forests, the species and typological diversity of mature spruce forests and spatial pattern of spruce forests along the south edge of their range. The composition and structure of Norway spruce plantations have been studied for various age classes and compared with mature natural spruce forests and pine plantations on the basis of field data. Remote sensing data and modeling approach were applied to estimate the spatial structure of spruce forests. It is found that mature plantations (over 80 years) become similar to natural forests in terms of structure and composition. The relationship between the distribution of spruce formations and the climatic and geomorphological conditions are confirmed. The proportion of spruce and spruce–aspen/birch communities follows the pattern of zones—the transition from the coniferous and broad-leaved forest zone to the broad-leaved forest zone. Despite the significant anthropogenic impact and the high proportion of plantations in the composition of Norway spruce forests (about 60–80%), their floristic and typological diversities correspond to such properties of zonal broad-leaved–coniferous communities. Over-matured plantations can provide valuable habitats for the re-establishment of native typological diversity. This makes it possible to use silviculture stands as an accelerated alternative to the natural recovery of disturbed habitats.


2014 ◽  
Vol 11 (9) ◽  
pp. 13433-13453 ◽  
Author(s):  
Y. F. Yao ◽  
X. Y. Song ◽  
A. H. Wortley ◽  
S. Blackmore ◽  
C. S. Li

Abstract. The Hengduan Mountains, with their strong altitudinal vegetation zonation, form a biodiversity hotspot which offers the potential for comparison between sites in order to understand how this zonation arose and how it has responded to climate change and human impacts through time. This paper is one of the studies covering a range of altitudes within this hotspot, and presents a 22 570 yr pollen record of vegetational and climatic change based on a core 320 cm in depth collected from Wenhai Lake on the Jade Dragon Snow Mountain, one of the highest peaks in the Hengduan Mountains region of Yunnan, Southwest China. From 22 570 to 21 140 cal. yr BP, the vegetation was dominated by broad-leaved forest (comprising mainly Quercus, Betula and Castanopsis), accompanied by coniferous Pinus and Abies and the drought-tolerant herb Artemisia, indicating a cool and dry climate. In the period between 21 140 and 19 350 cal. yr BP, the vegetation was still dominated by broad-leaved forest but with a notable increase in pollen of aquatic plants, implying a relatively warm and moderately humid climate. The period 19 350 to 17 930 cal. yr BP was a transition stage from broad-leaved forest to needle-leaved forest, reflecting a warm-humid climate at the beginning and a cold-dry one at the end. Between 17 930 and 9250 cal. yr BP, needle-leaved forest and broad-leaved forest alternated in dominance in the early stages, with the former taking the predominant position by the end of the period, suggesting a climate fluctuating between warm-humid and cold-dry. From 9250 cal. yr BP to present, the vegetation has been dominated by needle-leaved forest (comprising mainly Pinus and Abies), coupled with broad-leaved forest (mainly Quercus and Betula), reflecting a transition in climatic conditions from warm-humid to cold-humid. During this period, human activity increased in this region, with impacts on the vegetation which may be evidenced by the distinct decrease in Pinus and Quercus pollen and an increase in Polygonaceae pollen in the upper 30 cm of the core. The marked decline in Quercus pollen, in particular, in the Wenhai core can be correlated with that observed in the Haligu core (situated about 2 km away) between 2400 cal. yr BP and the present.


Author(s):  
R. E. Herfert

Studies of the nature of a surface, either metallic or nonmetallic, in the past, have been limited to the instrumentation available for these measurements. In the past, optical microscopy, replica transmission electron microscopy, electron or X-ray diffraction and optical or X-ray spectroscopy have provided the means of surface characterization. Actually, some of these techniques are not purely surface; the depth of penetration may be a few thousands of an inch. Within the last five years, instrumentation has been made available which now makes it practical for use to study the outer few 100A of layers and characterize it completely from a chemical, physical, and crystallographic standpoint. The scanning electron microscope (SEM) provides a means of viewing the surface of a material in situ to magnifications as high as 250,000X.


2019 ◽  
Vol 19 (1) ◽  
pp. 307-322
Author(s):  
Václav Pravda

Summary This article elaborates on the issue of recognition and enforcement of foreign arbitral awards in the Russian Federation. It is common knowledge that foreign companies seeking R&E in Russia suffered damage because of the broad interpretation of Russian public policy in the past decades. However, it is uncertain how the present judicial development appears like and where it will lead in the future. The article specifically considers two basic ideas on the issue at hand: one is slightly critical (Karabelnikov) while the second is rather optimistic in regard with the recent development (Zykov). The main goal is to introduce the issue to the respective readers and to try to inflame a discussion.


Author(s):  
I. V. Bukhtiyarov

The article presents the results of the analysis of health, working conditions and prevalence of adverse production factors, the structure of the detected occupational pathology in the working population of the Russian Federation. The article presents Statistical data on the dynamics of the share of workplaces of industrial enterprises that do not meet hygienic standards, occupational morbidity in 2015-2018 for the main groups of adverse factors of the production environment and the labor process. The indicators of occupational morbidity over the past 6 years in the context of the main types of economic activity, individual subjects of the Russian Federation, classes of working conditions, levels of specialized occupational health care. The role of the research Institute of occupational pathology and occupational pathology centers in solving organizational, methodological and practical tasks for the detection, treatment, rehabilitation and prevention of occupational diseases is shown. The basic directions of activity in the field of preservation and strengthening of health of workers, and also safety at a workplace are defined.


1996 ◽  
pp. 64-67 ◽  
Author(s):  
Nguen Nghia Thin ◽  
Nguen Ba Thu ◽  
Tran Van Thuy

The tropical seasonal rainy evergreen broad-leaved forest vegetation of the Cucphoung National Park has been classified and the distribution of plant communities has been shown on the map using the relations of vegetation to geology, geomorphology and pedology. The method of vegetation mapping includes: 1) the identifying of vegetation types in the remote-sensed materials (aerial photographs and satellite images); 2) field work to compile the interpretation keys and to characterize all the communities of a study area; 3) compilation of the final vegetation map using the combined information. In the classification presented a number of different level vegetation units have been identified: formation classes (3), formation sub-classes (3), formation groups (3), formations (4), subformations (10) and communities (19). Communities have been taken as mapping units. So in the vegetation map of the National Park 19 vegetation categories has been shown altogether, among them 13 are natural primary communities, and 6 are the secondary, anthropogenic ones. The secondary succession goes through 3 main stages: grassland herbaceous xerophytic vegetation, xerophytic scrub, dense forest.


Sign in / Sign up

Export Citation Format

Share Document