scholarly journals Ecological characteristics of edificators and assectators of the southern taiga forests of the Chelyabinsk Region

2017 ◽  
Vol 6 (4) ◽  
pp. 27-32
Author(s):  
Irina Anatolievna Getmanets ◽  
Irina Valerievna Moskvina ◽  
Boris Alexandrovich Artemenko
Keyword(s):  
Computer Software ◽  
Southern Taiga ◽  
Limiting Factors ◽  
Western Slope ◽  
Tall Grass ◽  
Siberian Spruce ◽  
Spruce Stands ◽  
Competitive Species ◽  
Chelyabinsk Region ◽  
Number Of Individuals

The following paper deals with the phytoindication of ecotopes of spruce forests on the western slope of Mount Lipovaya within the territory of the Kusinsky District. This phytoindication was made on the basis of D.N. Tsyganovs ecological scales and with the help of EcoScaleWin computer software. The cenotic properties of species are estimated by their abundance in typical communities; limiting factors, ecological valence and tolerance are determined; the degree of use of ecological potencies and the efficiency of development of ecological space are estimated and the aggregate parameters of habitats are described. The vertical structure and composition of spruce stands are estimated, it is shown that Picea obovata is noted in all tiers, where Betula pendula and Pinus sylvestris are also present, but their numbers range from 10-20% of the total number of individuals in the study area. The unevenness of the distribution of the stand is noted. The ratio of the species of eco-and-coenotic groups is analyzed and it is shown that in the communities the species of the boreal and boron groups are predominated, the nemoral and meadow (including tall grass) groups contribute significantly, a small percentage belongs to the non-forest group species (wetland and plurizonal). Biomorphological analysis revealed that the life form is stable, it is represented by a single-stem tree with different shape of the crown, which indicates the different ages of Siberian spruce. The investigated phytocenosis is attributed to the late succession communities, the late stage of restorative succession, because the dominant is a typically competitive species. The research materials can serve as a basis for plant communities and coenotic populations monitoring, for identifying of the potential species richness of phytocenoses.

scholarly journals Carbon balance of a Finnish bog: temporal variability and limiting factors

2021 ◽  
Author(s):  
Pavel Alekseychik ◽  
Aino Korrensalo ◽  
Ivan Mammarella ◽  
Samuli Launiainen ◽  
Eeva-Stiina Tuittila ◽  
...  
Keyword(s):  
Eddy Covariance ◽  
Wind Direction ◽  
Gross Primary Production ◽  
Net Ecosystem Exchange ◽  
Source Area ◽  
Growing Season ◽  
Co2 Exchange ◽  
Southern Taiga ◽  
Limiting Factors ◽  
Ch4 Emission

Abstract. Pristine boreal mires are known as substantial sinks of carbon dioxide (CO2) and net emitters of methane (CH4). Natural bogs constitute a major fraction of boreal mires. However, the bog CO2 and CH4 balances are poorly known, having been largely estimated based on discrete and short term measurements by manual chambers, and seldom using the eddy-covariance (EC) technique. Eddy-covariance (EC) measurements of CO2 and CH4 exchange were conducted in the Siikaneva mire complex in southern Finland in 2011–2016. The site is a patterned bog having a moss/sedge/shrub vegetation typical of Eurasian southern Taiga, with several ponds near the EC tower. The study presents a complete series of CO2 and CH4 EC flux measurements and identifies the environmental factors controlling the ecosystem-atmosphere CO2 and CH4 exchange. A 6-year average growing season (May–September) cumulative CO2 exchange of −60 g C m−2 was observed, which partitions into mean total respiration (Re) of 167 (146–197 annually) g C m−2 and mean gross primary production (GPP) of 228 (193–257 annually) g C m−2, while the corresponding CH4 emission amounts to 7.1 (6.4...8.4) g C m−2. The contribution of October–December CO2 and CH4 fluxes to the cumulative sums was not negligible based on the measurements during one winter. GPP, Re and CH4 fluxes increased with temperature, and did not show a strong decline even after a substantial water table drawdown in 2011. Instead, GPP, Re and FCH4 became suppressed in cool, cloudy and wet conditions of 2012. May–September cumulative net ecosystem exchange (NEE) of 2013–2016 remained at about −73 g C m−2, in contrast to the hot and dry year 2011 and the wet and cool year 2012, when suboptimal weather likely degraded the net sink by 20 and 40 g C m−2, correspondingly. The cumulative growing season sums of GPP and CH4 emission showed a strong positive relationship. The EC source area was found to be comprised of 8 distinct surface types. However, footprint analyses revealed that contributions of different surface types varied only within 10–20 % with respect to wind direction and stability conditions. Consequently, no clear link between CO2 and CH4 fluxes and footprint composition was found, despite the apparent variation of fluxes with wind direction.

Intraspecies and age polymorphism of Norway spruce (Picea Abies (L.) Karst.) in conditions of the Vologda region

10.12737/2177 ◽  
2014 ◽  
Vol 3 (4) ◽  
pp. 24-32
Author(s):  
Дружинин ◽  
Fedor Druzhinin ◽  
Макаров ◽  
Yuriy Makarov
Keyword(s):  
Southern Taiga ◽  
Growing Up ◽  
Mixed Stands ◽  
Breast Height ◽  
Vologda Region ◽  
European North ◽  
Tree Descriptions ◽  
Spruce Stands ◽  
Southern Taiga Subzone ◽  
Bark Structure

Objects of study are located in the southern taiga subzone of the European North and presented by spruce stands of wood sorrel types of site conditions with mixed stands. Lying of test areas was carried out in young stands, middle-aged, maturing and mature forests on the territory of Griazovets district of Vologda Region. Nature of bark structure at breast height, type of branching on twigs growing up in the middle of the crowns was determined. Processing of tree descriptions was performed on all study objects where 4 types of spruce were recorded by the nature of the structure of bark. By type of branches presence of three forms of spruce were defined.

scholarly journals Assessment of phenotypic plasticity of spruce species Picea abies (L.) Karst. and P. obovata (Ledeb.) on provenances tests in European North of Russia

2019 ◽  
Vol 65 (2) ◽  
pp. 121-128
Author(s):  
Elena Nakvasina ◽  
Nadezhda Demina ◽  
Nadezhda Prozherina ◽  
Natalia Demidova
Keyword(s):  
Phenotypic Plasticity ◽  
Picea Abies ◽  
Southern Taiga ◽  
Russian Plain ◽  
Distribution Area ◽  
High Plasticity ◽  
The North ◽  
European North ◽  
Northern Areas ◽  
Spruce Stands

Abstract Phenotypic plasticity of 22 spruce provenances in three test plots located in the European North of Russia was studied. Parent spruce stands are located within the Russian Plain and are represented by Picea abies (L.) Karst., P. obovata (Ledeb.) and two introgressive hybrids. In the test plots located in the middle and southern taiga subzones P. abies provenances are tested northward of its distribution area and P. obovata provenances are tested within the distribution area and nearby its boundaries. phenotypic plasticity of the spruce provenances was assessed. Straight-line regression coefficient based on survival, diameter, and height was calculated. All provenances are divided into two groups: plastic and non-plastic provenances. High plasticity is observed more often for P. abies and hybrids forms with properties of P. abies. Plastic provenances based on three parameters grow in the Leningrad, Pskov, Vologda, Kostroma and Karelia. Area of parent stands growing is quite small-size and lies between 56º30´ – 61º40´ N and 30º30´ – 42º30´ E. Adaptive provenances of P. obovata and its related hybrids forms grow in the North-Eastern part of the Russian Plain that could be consequence of its distribution in Holocene. Picea abies being the more adaptive species would be more responsive to climate changes in terms of survival and growth rate than P. obovata. Therefore, in case of sustainable climate warming in the Northern areas of the Russian Plain, the further propagation and major distribution of P. abies with further competitive replacement of P. obovata can be expected.

Replicability of an epibenthic sampler

1991 ◽  
Vol 71 (1) ◽  
pp. 153-166 ◽  
Author(s):  
T. Brattegard ◽  
J. H. Fosså
Keyword(s):  
Correspondence Analysis ◽  
Diversity Index ◽  
Similarity Index ◽  
Rank Correlation ◽  
Acceptable Level ◽  
Western Slope ◽  
Spearman Rank Correlation ◽  
Spearman Rank ◽  
Cost Efficient ◽  
Number Of Individuals

Hyperbenthos was sampled at six stations on the western slope of the Norwegian Trough. Four hauls, two day and two night replicates were taken at each station. The replicates were analyzed based on all sampled individuals of Mysidacea and Decapoda Natantia using Shannon diversity index, Spearman rank correlation, G-test, Bray-Curtis similarity index and Correspondence Analysis. The sampler provided samples of mysids and shrimps with an acceptable level of replicability based on number of individuals and diversity. In a cost-efficient context it is satisfactory to take only one sample at a station.

scholarly journals State of spruce stands in Southern Taiga forests in Udmurt Republic Taiga Zone

2021 ◽  
Vol 25 (4) ◽  
pp. 34-43
Author(s):  
I.L. Bukharina ◽  
◽  
A.S. Pashkova ◽  
D N. Udalov ◽  
M.N. Starkov ◽  
...  
Keyword(s):  
Forest Litter ◽  
Southern Taiga ◽  
Living Condition ◽  
Forest Area ◽  
Taiga Zone ◽  
Forest Stands ◽  
Siberian Spruce ◽  
Study Results ◽  
Udmurt Republic ◽  
Taiga Forests

The study results of coniferous stands and the description of stands in the southern taiga forests of the taiga zone within the Udmurt Republic (on the territory of the Yakshur-Bodya, Igrinsky and Kez forest districts) are presented. The climatic indicators of the study year are presented in comparison with the average long-term data for the studied areas. The taxational characteristics of forest stands are given, the indicators of the morphological profile, humidity, and cellulose-decomposing activity of forest litter are presented. Studies have shown that the cellulose-decomposing activity of forest litter depends on its moisture content, which is associated with the values of the basal area per hectar of stands in the studied sample areas. No differences in the indicator of cellulose-decomposing activity were found in the sample areas in the Igrinsky forestry. The highest values of this indicator were determined in the sample area No. 1 in the Kez forestry. The lowest values of the cellulose-decomposing activity of forest litter were observed in the sample areas No. 1 and No. 3 in the Yakshur-Bodya forest area. The physiological and biochemical parameters of Siberian spruce (Pícea obováta Ledeb.) were analyzed and compared in trees of good and satisfactory living conditions, which did not show statistically significant differences in the content of chlorophylls and carotenoids in the needles. A significantly high content of photosynthetic pigments and tannins in Siberian spruce conifers was found in the sample areas in the Igrinsky forest area. Similar results were obtained for individuals of a satisfactory living condition, with the exception of the content of tannins in conifers. It was found that the high content of chlorophyll a in Siberian spruce needles is usually accompanied by an increased content of tannins and a low concentration of ascorbic acid. It is shown that in general, the potential of Siberian spruce individuals associated with the biochemical level of the formation of adaptive reactions is highest in plants in the northern regions of the republic, i.e. in areas with more extreme growing conditions. Materials were obtained on the basis of which it is possible to develop a program for monitoring plantings and restoring forest stands.

Software pattern recognition applied to nanodiffraction patterns from a STEM instrument

1986 ◽  
Vol 44 ◽  
pp. 694-695
Author(s):  
G.Y. Fan ◽  
J.M. Cowley
Keyword(s):  
Image Processing ◽  
Pattern Recognition ◽  
Computer Software ◽  
Processing System ◽  
Light Level ◽  
Host Computer ◽  
Low Light ◽  
Image Processing System ◽  
Recent Developments ◽  
On Line

In recent developments, the ASU HB5 has been modified so that the timing, positioning, and scanning of the finely focused electron probe can be entirely controlled by a host computer. This made the asynchronized handshake possible between the HB5 STEM and the image processing system which consists of host computer (PDP 11/34), DeAnza image processor (IP 5000) which is interfaced with a low-light level TV camera, array processor (AP 400) and various peripheral devices. This greatly facilitates the pattern recognition technique initiated by Monosmith and Cowley. Software called NANHB5 is under development which, instead of employing a set of photo-diodes to detect strong spots on a TV screen, uses various software techniques including on-line fast Fourier transform (FFT) to recognize patterns of greater complexity, taking advantage of the sophistication of our image processing system and the flexibility of computer software.

Effects of sterilization modes on the mechanical strengths of plaster of paris implants

1989 ◽  
Vol 47 ◽  
pp. 890-891
Author(s):  
K. Cowden ◽  
B. Giammara ◽  
T. Devine ◽  
J. Hanker
Keyword(s):  
Gamma Radiation ◽  
Calcium Sulfate ◽  
Significant Loss ◽  
Potassium Sulfate ◽  
Limiting Factors ◽  
Radiation Sterilization ◽  
Plaster Of Paris ◽  
Hardness Tester ◽  
Dry Heat ◽  
Calcium Sulfate Hemihydrate

Plaster of Paris (calcium sulfate hemihydrate, CaSO4. ½ H2O) has been used as a biomedical implant material since 1892. One of the primary limiting factors of these implants is their mechanical properties. These materials have low compressive and tensile strengths when compared to normal bone. These are important limiting factors where large biomechanical forces exist. Previous work has suggested that sterilization techniques could affect the implant’s strength. A study of plaster of Paris implant mechanical and physical properties to find optimum sterilization techniques therefore, could lead to a significant increase in their application and promise for future use as hard tissue prosthetic materials.USG Medical Grade Calcium Sulfate Hemihydrate Types A, A-1 and B, were sterilized by dry heat and by gamma radiation. Types A and B were additionally sterilized with and without the setting agent potassium sulfate (K2SO4). The plaster mixtures were then moistened with a minimum amount of water and formed into disks (.339 in. diameter x .053 in. deep) in polyethylene molds with a microspatula. After drying, the disks were fractured with a Stokes Hardness Tester. The compressive strengths of the disks were obtained directly from the hardness tester. Values for the maximum tensile strengths σo were then calculated: where (P = applied compression, D = disk diameter, and t = disk thickness). Plaster disks (types A and B) that contained no setting agent showed a significant loss in strength with either dry heat or gamma radiation sterilization. Those that contained potassium sulfate (K2SO4) did not show a significant loss in strength with either sterilization technique. In all comparisons (with and without K2SO4 and with either dry heat or gamma radiation sterilization) the type B plaster had higher compressive and tensile strengths than that of the type A plaster. The type A-1 plaster however, which is specially modified for accelerated setting, was comparable to that of type B with K2SO4 in both compressive and tensile strength (Table 1).

Mosaic Mapping: A Means of Tiling Images to Shorten Acquisition Speed for Lower - Magnification SEM Images and Wavelength Dispersive Spectrometers (WDS) X-Ray Maps

1996 ◽  
Vol 54 ◽  
pp. 438-439
Author(s):  
J.D. Geller ◽  
C.R. Herrington
Keyword(s):  
Limiting Factors ◽  
X Rays ◽  
Angular Range ◽  
Acceptance Angle ◽  
Sem Images ◽  
Worst Case ◽  
X Ray ◽  
Focusing Distance ◽  
Layered Crystals ◽  
Working Distance

The minimum magnification for which an image can be acquired is determined by the design and implementation of the electron optical column and the scanning and display electronics. It is also a function of the working distance and, possibly, the accelerating voltage. For secondary and backscattered electron images there are usually no other limiting factors. However, for x-ray maps there are further considerations. The energy-dispersive x-ray spectrometers (EDS) have a much larger solid angle of detection that for WDS. They also do not suffer from Bragg’s Law focusing effects which limit the angular range and focusing distance from the diffracting crystal. In practical terms EDS maps can be acquired at the lowest magnification of the SEM, assuming the collimator does not cutoff the x-ray signal. For WDS the focusing properties of the crystal limits the angular range of acceptance of the incident x-radiation. The range is dependent upon the 2d spacing of the crystal, with the acceptance angle increasing with 2d spacing. The natural line width of the x-ray also plays a role. For the metal layered crystals used to diffract soft x-rays, such as Be - O, the minimum magnification is approximately 100X. In the worst case, for the LEF crystal which diffracts Ti - Zn, ˜1000X is the minimum.

Computer-Assisted High-Re Solution TEM

1990 ◽  
Vol 48 (1) ◽  
pp. 162-163
Author(s):  
F.A. Ponce ◽  
H. Hikashi
Keyword(s):  
Signal To Noise Ratio ◽  
Accurate Determination ◽  
Computer Software ◽  
Video Camera ◽  
Image Contrast ◽  
Objective Lens ◽  
Computer Assisted ◽  
Optical Parameters ◽  
Astigmatism Correction

The determination of the atomic positions from HRTEM micrographs is only possible if the optical parameters are known to a certain accuracy, and reliable through-focus series are available to match the experimental images with calculated images of possible atomic models. The main limitation in interpreting images at the atomic level is the knowledge of the optical parameters such as beam alignment, astigmatism correction and defocus value. Under ordinary conditions, the uncertainty in these values is sufficiently large to prevent the accurate determination of the atomic positions. Therefore, in order to achieve the resolution power of the microscope (under 0.2nm) it is necessary to take extraordinary measures. The use of on line computers has been proposed [e.g.: 2-5] and used with certain amount of success.We have built a system that can perform operations in the range of one frame stored and analyzed per second. A schematic diagram of the system is shown in figure 1. A JEOL 4000EX microscope equipped with an external computer interface is directly linked to a SUN-3 computer. All electrical parameters in the microscope can be changed via this interface by the use of a set of commands. The image is received from a video camera. A commercial image processor improves the signal-to-noise ratio by recursively averaging with a time constant, usually set at 0.25 sec. The computer software is based on a multi-window system and is entirely mouse-driven. All operations can be performed by clicking the mouse on the appropiate windows and buttons. This capability leads to extreme friendliness, ease of operation, and high operator speeds. Image analysis can be done in various ways. Here, we have measured the image contrast and used it to optimize certain parameters. The system is designed to have instant access to: (a) x- and y- alignment coils, (b) x- and y- astigmatism correction coils, and (c) objective lens current. The algorithm is shown in figure 2. Figure 3 shows an example taken from a thin CdTe crystal. The image contrast is displayed for changing objective lens current (defocus value). The display is calibrated in angstroms. Images are stored on the disk and are accessible by clicking the data points in the graph. Some of the frame-store images are displayed in Fig. 4.

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