scholarly journals FEATURES OF ULMUS PUMILA L. SEEDLING COPPICE ON ARABLE LANDS IN THE STEPPE ZONE OF KHAKASSIA

2018 ◽  
Vol 13 (4) ◽  
pp. 61-65 ◽  
Author(s):  
Марина Мартынова ◽  
Marina Martynova
Keyword(s):  
Arable Land ◽  
Steppe Zone ◽  
Dry Mass ◽  
Windward Side ◽  
Leeward Side ◽  
Optimal Size ◽  
Ulmus Pumila ◽  
Crown Density ◽  
Grass Stand ◽  
Shelter Belts

In the 90s of the last century, the volume of spontaneous conservation of arable land in Central Siberia amounted to 1.1 million hectares. Unproductive land with forest melioration facilities, which are used as pastures, underwent spontaneous conservation. Currently, there is an active overgrowing of fallow fields with elm trees and shrubs. In order to use forest forests effectively, it is necessary to remove excess tree-shrub vegetation. Studies of the characteristics of the seed renewal of Ulmus pumila L., growing on spontaneously conserved, highly degraded lands used as pastures, were carried out in 2013–2017. in the steppe zone in the territory of Khakassia. The term conservation of arable land is 17 years. Conditions for the growth of natural renewal Ulmus pumila adverse. 47% of the undergrowth of Ulmus pumila belonged to the category of sanitation - weakened. The main part, 73%, of the undergrowth was small and did not exceed 50 cm in height. On interband lanes, natural renewal was unevenly distributed. On the leeward side of the parental forest shelter belts at a distance of up to 20 m, 65% grew; on the windward side at the same distance - 18% of all existing Ulmus pumila. The optimal size of Ulmus pumila at the age of 10 years was from 1.0 to 2.5 thousand units per hectare, since with these indicators the maximum productivity of grass stand was obtained - 12.7 kg per hectare of air-dry mass. In order to increase the productivity of the grass stand at the forest pasture, it is necessary to carry out a radical improvement in the destruction of excessive shrub vegetation. Woody plants of less than 2.5 thousand units per hectare should be left on the fields, provided that they are evenly distributed over the territory so that Ulmus pumila, having reached its adult state, forms plantations with optimum crown density, which should not exceed the value of 0.2.

scholarly journals The current state of the pine shelter belt in the steppe zone of the Krasnoyarsk Territory

2021 ◽  
Vol 20 (1) ◽  
pp. 269-273
Author(s):  
A. I. Lobanov ◽  
V. V Mulyava ◽  
N. A. Konovalova
Keyword(s):  
Arable Land ◽  
Average Diameter ◽  
Steppe Zone ◽  
Forest Belt ◽  
Average Height ◽  
Current State ◽  
Pine Trees ◽  
Shelter Belts ◽  
Forest Belts ◽  
Forest Shelter Belts

xModern forest shelter belts do not fully protect arable land and most often have a different life state. In theseconditions, the preservation of forest belts, their performance of protective functions in the system of agroforestry andother complex measures remains an urgent task. The studies were carried out in a field-protective forest belt located in thevicinity of the Oktyabrsky village of the Krasnoturansky district of the Krasnoyarsk Territory, where a temporary test plotwas laid using generally accepted methods. The aim of the research was to study the current state of this forest belt by identifying the sanitary state and preservation of the stand and growth rates of Scots pine. Analysis of the current state of thestand showed that the average category of the state of trees is 1.3 points. The stand safety is 44.9%. Pine trees at the age of 28after planting have reached an average height of 11.6 m with an average diameter of 19.1 cm. The forest belt has an optimalopenwork-blown design and is capable of self-renewal naturally. To prevent further degradation of arable leached chernozems in treeless areas of the steppe zone of the Krasnoyarsk Territory, it is advisable to create pine forest shelter belts.

scholarly journals ASSESSMENT OF THE IMPACT OF A PROTECTIVE FOREST BELT ON SNOW DEPOSITION IN UNPAK LNAU " KOLOS»

2020 ◽  
Vol 10 (3) ◽  
pp. 43-53
Author(s):  
Olesya Gribacheva ◽  
Aleksey Chernodubov ◽  
Dmitriy Sotnikov
Keyword(s):  
Snow Cover ◽  
Snow Accumulation ◽  
Windward Side ◽  
Leeward Side ◽  
Forest Belt ◽  
Shelter Belts ◽  
Minimum Height ◽  
The Impact ◽  
The City ◽  
Forest Shelter Belts

The authors in this article reviewed and analyzed works that consider the features of the distribution of snow cover under the influence of field protection belts. The aim of the work is to study the influence of forest shelter belts on snow accumulation depending on the climatic conditions of the city of Lugansk. The research was carried out in the city of Lugansk, on the basis of the educational and production agricultural complex "Kolos" of the Lugansk national agrarian university (UNPAK LNAU "Kolos"). The object of research is forest shelter belts of openwork-blown structure. A VS-43 snow meter was used to measure the mass of the snow cover. The depth of the snow cover was measured with a portable snow gauge M-104. The density of the snow mass and the water reserve in the sample were calculated mathematically. The authors found that the average height of snow cover on the windward side of the shelter belt is from 6.00 to 10.25 cm and the sample weight is from 33.50 to 68.75 grams. The data obtained indicate that more snow accumulates on the leeward side of the field protection strip than on the windward side. The minimum height of the snow cover on the windward side is 3 cm, and the maximum is 9 cm. Whereas the minimum height of the snow cover on the leeward side is 10 cm, and the maximum is 17 cm. The authors emphasize that as a result falling out of common ash from the strip, there is a tendency of transformation of the strip from openwork-blown to blown, when the height of the snow cover rarely exceeds 1 m and snow is blown out from under the canopy of the forest belt.

Investigation on the drag effect of a rolling element confined in the cavity of a cylindrical roller bearing

2021 ◽  
pp. 135065012110260
Author(s):  
Wenjun Gao ◽  
Shuo Zhang ◽  
Xiaohang Li ◽  
Zhenxia Liu
Keyword(s):  
Open Space ◽  
Roller Bearing ◽  
Flow Characteristics ◽  
Experimental Tests ◽  
Windward Side ◽  
Leeward Side ◽  
Drag Effect ◽  
Rolling Element ◽  
Cylindrical Roller Bearing ◽  
Cylindrical Roller

In cylindrical roller bearings, the drag effect may be induced by the rolling element translating in a fluid environment of the bearing cavity. In this article, the computational fluid dynamics method and experimental tests are employed to analyse its flow characteristics and pressure distribution. The results indicate that the pressure difference between the windward side and the leeward side of the cylinder is raised in view of it blocking the flow field. Four whirl vortexes are formed in four outlets of two wedge-shaped areas between the front part of the cylindrical surface and adjacent walls for the cylinder of L/ D = 1.5 at Re = 4.5 × 103. Vortex shedding is found in the direction of cylinder axis at Re = 4.5 × 104. The relationship between drag coefficient and Reynolds number is illustrated, obviously higher than that of the two-dimensional cylinder in open space.

scholarly journals 2.5D Flexible Wind Sensor Using Differential Plate Capacitors

Sensors ◽  
2021 ◽  
Vol 21 (9) ◽  
pp. 3101
Author(s):  
Yu Wan ◽  
Zhenxiang Yi
Keyword(s):  
Wind Speed ◽  
Wind Direction ◽  
Parallel Plate ◽  
Electrode Array ◽  
Copper Electrode ◽  
Windward Side ◽  
Leeward Side ◽  
Electrode Layer ◽  
Young’S Moduli ◽  
Speed Up

In this paper, a novel 2.5-dimensional (2.5D) flexible wind sensor is proposed based on four differential plate capacitors. This design consists of a windward pillar, two electrode layers, and a support layer, which are all made of polydimethylsiloxane (PDMS) with different Young’s moduli. A 2 mm × 2 mm copper electrode array is located on each electrode layer, forming four parallel plate capacitors as the sensitive elements. The wind in the xy-plane tilts the windward pillar, decreasing two capacitances on the windward side and increasing two capacitances on the leeward side. The wind in the z-axis depresses the windward pillar, resulting in an increase of all four capacitances. Experiments demonstrate that this sensor can measure the wind speed up to 23.9 m/s and the wind direction over the full 360° range of the xy-plane. The sensitivities of wind speed are close to 4 fF·m−1·s and 3 fF·m−1·s in the xy-plane and z-axis, respectively.

Air movement and heat loss from sheep. II. Thermal insulation of fleece in wind

1980 ◽  
Vol 209 (1175) ◽  
pp. 209-217 ◽  
Keyword(s):  
Thermal Diffusivity ◽  
Heat Loss ◽  
Thermal Insulation ◽  
General Relation ◽  
Windward Side ◽  
Leeward Side ◽  
Sensible Heat ◽  
Bulk Resistance ◽  
Air Movement ◽  
Dimensionless Constant

Penetration of an animal’s coat by wind reduces its thermal insulation and increases heat loss to the environment. From studies of the sensible heat loss from a life-sized model sheep covered with fleece, the average fleece resistance r¯ f (s cm -1 ) was related to windspeed u (m s -1 ) by 1/ r¯ f ( u ) = l/ r¯ f (0) + cu , where c is a dimensionless constant. As c is expected to be inversely proportional to coat depth Î , the more general relation k¯ ( u ) = k¯ (0) + c'u was evaluated, where k¯ = Î / r¯ f is the thermal diffusivity (cm 2 s -1 ) of the fleece and c' = cÎ is another constant (cm). The orientation of the model to the wind had little effect on the bulk resistance of the fleece, but the resistance on the windward side was substantially lower than on the leeward side.

scholarly journals On the Issue of Research of Information Support of Sustainable Agricultural Landscapes Formation

2020 ◽  
Keyword(s):  
Agricultural Land ◽  
Ecological Impact ◽  
Arable Land ◽  
Agricultural Landscapes ◽  
Information Support ◽  
Erosion Processes ◽  
Shelter Belts ◽  
Forest Belts ◽  
Methodological Approaches ◽  
The Creation

Purpose. To characterize the methodological approaches that we develop in the formation of a system of information support for the creation and maintenance of the functioning of modern sustainable agricultural landscapes and to show the results of their implementation on the example of the territory of some agricultural enterprises of the Kharkiv region. Methods. Cartographic, geoinformation analysis, calculation, statistical and mathematical. Results. Some results of the work of the collective on the issues of information support for the creation and maintenance of the functioning of modern sustainable agricultural landscapes. Namely, verification of erosion models, studies of the functionality of shelter belts, the formation of an agroeconet (an extensive network of natural and quasi-natural landscapes) on agricultural land massifs, which ensures the maintenance of stable functioning of meso and macrolevel agrolandscapes, as well as the experience of using magnetic prospecting methods to verify the results of mathematical modeling of erosion processes. Conclusions. A number of methodological approaches to information support of the formation of sustainable agricultural landscapes in the natural and socio-economic conditions of Ukraine have been developed. They relate to the functioning of anti-erosion measures of permanent action, the processes of modern transformation of agro-landscapes, the ecological impact of erosion processes on the environment. The connection between the length of forest belts per unit of arable land and soil erosion is shown. A methodical approach has been developed to estimate the amount of soil washed away from arable land and to calculate the measures necessary to eliminate its harmful effects on the environment.

scholarly journals Dust-related impacts of mining operations on rangeland vegetation and soil: a case study in Yazd province, Iran

2021 ◽  
Author(s):  
Shahab IbrahimPour ◽  
Alireza KhavaninZadeh ◽  
Ruhollah Taghizadeh mehrjardi ◽  
Hans De Boeck ◽  
Alvina Gul
Keyword(s):  
Seed Germination ◽  
Vegetation Cover ◽  
Microbial Respiration ◽  
Germination Rate ◽  
Windward Side ◽  
Leeward Side ◽  
Mining Operations ◽  
Soil Microbial ◽  
Soil Microbial Respiration ◽  
The Impact

Abstract Destructive mining operations are affecting large areas of natural ecosystems, especially in arid lands. The present study aims at investigating the impact of iron mine exploitation on vegetation and soil in Nodoushan (Yazd province, central Iran). Based on the dominant wind, topography, slope, vegetation and soil of the area, soil and vegetation parameters close to ​the mine were recorded and analyzed according to the distance from the mine. In order to obtain the vegetation cover, a transect and plot on the windward and leeward side of the mine, with 100 m intervals and three replicates at each sampling location was used, yielding 96 soil samples. The amount of dust on the vegetation, the seed weight and seed germination rate of Artemisia sp. as the dominant species within the area, and the soil microbial respiration were measured. The relationship between vegetation cover and distance from the mine was not linear, which was due to an interplay between pollution from the mine and local grazing, while other factors did increase or decrease linearly. The results showed that, as the distance from the mine increased, the weight of 1000 seeds of Artemisia sp. was significantly increased from 271 to 494 mg and seed germination rate and soil microbial respiration were significantly increased from 11.7 to 48.4 % and from 4.5 to 5.9 mg CO2 g− 1 soil day− 1 respectively, while the amount of dust significantly decreased from 43.5 to 6 mg (g plant)−1 between the distance of 100 to 600 m from the mine in the leeward direction. A similar trend was observed in the windward side, though negative effects were lower compared to the same distance along the leeward sample locations. The direct and indirect effects on plant growth and health from mining impacts generally decreased linearly with increasing distance from the mine, up to at least 600 m. Our study serves as a showcase for the potential of bio-indicators as a cost-effective method for assessing impacts of mining activities on the surrounding environment.

scholarly journals Assessment of adaptive capacity of native and adventive species of trees and shrubs in Dnipro region

2021 ◽  
Vol 50 ◽  
pp. 12-21
Author(s):  
I. A. Ivanko ◽  
A. F. Kulik
Keyword(s):  
Invasive Species ◽  
Peroxidase Activity ◽  
Tree Species ◽  
Native Species ◽  
Steppe Zone ◽  
Morus Alba ◽  
Acer Platanoides ◽  
Ulmus Pumila ◽  
Acer Negundo ◽  
Ulmus Laevis

Nowadays, deterioration and loss of ecological functions of urban tree and shrub plantations take place in Europe and, in particular, in Ukraine; it was noted that their number is insufficient to counteract the negative impact of global climate change and protect the population against industrial pollution effects. The issue of resistance of native and adventitious tree species used in the plantations of industrial cities remains relevant; it necessitates the assessment of physiological and biochemical aspects of their adaptation to extreme environmental factors, such as moisture limit in the steppe zone, periodic dangerously low winter temperatures and anthropo-technogenic load (in large urban agglomerations). In order to optimize the assortment of tree species of large megalopolises of the steppe zone of Ukraine and determine their potential resistance to anthropogenic pressures the study was conducted in conditionally clean forest biogeocenoses of the Samara River levee zone and in artificial plantations on the territories located in the coastal zone of the Dnipro River within 1500 m from the Prydneprovskaya thermal electric station (PTES, Dnipro city). It well known that the TPP is the source of atmospheric air pollution by such heavy metals as lead and cadmium. A study of the activity of antioxidant protection enzymes in leaves of native and adventive tree species showed that in the zone of Prydneprovskaya TES impact there was an increase of guaiacol peroxidase activity in Acer platanoides, Ulmus minor, Morus alba; benzidine peroxidase in Acer negundo, Ulmus laevis, Acer platanoides; catalase in A. platanoides, A. negundo, U. laevis, Ulmus pumila and Robinia pseudoasasia. High peroxidase activity, which is complemented by higher catalase activity, indicates the relative resistance of these species to atropo-technogenic pressures supported by antioxidant defense mechanisms. Total chlorophyll content (Chla + Chlb) in leaves of native species Ulmus laevis, Acer platanoides and adventive Morus alba decreased in the zone of TPP impact in relation to conditionally clean areas. The ratio of chlorophyll a to chlorophyll b in contaminated areas significantly increased in leaves of native species Ulmus laevis, Ulmus minor, Acer platanoides compared with control. The invasive species Acer negundo, Morus alba, Ulmus pumila had no significant changes in this indicator. In invasive species such as Ulmus pumila, Acer negundo there was an increase in leaf mass, which may indicate adaptation of these species to anthropogenically altered growth conditions.

scholarly journals Topographical Influence on Precipitation Distribution in Different Ranges of Western Himalayas

1995 ◽  
Vol 26 (4-5) ◽  
pp. 259-284 ◽  
Author(s):  
Pratap Singh ◽  
K. S. Ramasastri ◽  
Naresh Kumar
Keyword(s):  
Precipitation Intensity ◽  
Windward Side ◽  
Leeward Side ◽  
Western Himalayas ◽  
Precipitation Distribution ◽  
Post Monsoon ◽  
Seasonal Characteristics ◽  
Annual Distribution

Seasonal and annual distribution of rainfall and snowfall with elevation has been studied for outer, middle and greater Himalayan ranges of Chenab basin in the western Himalayas. Rainfall and snowfall exhibited different trends with elevation on the windward and leeward slopes of the three ranges of Himalayas. Seasonal characteristics of rainfall have shown a spill over effect on leeward side during winter, pre-monsoon, and post-monsoon seasons in the outer Himalayas. The role of orography in the middle Himalayas was found to be more pronounced for both rainfall and snowfall in comparison to other ranges of Himalayas. Variation of snowfall with elevation was more prominent in comparison to variation of rainfall. In the greater Himalayan range it is found that rainfall descreases exponentially with elevation and snowfall increases linearly. Rainfall becomes negligible at elevations beyond 4,000 m on the windward side of the greater Himalayan range. Efforts have also been made to explain whether variation in precipitation is due to changes in precipitation intensity or number of precipitation days or a combination of both.

scholarly journals Numerical Assessment on Rotation Effect of the Stagnation Surface on Nanoparticle Deposition in Flame Synthesis

Materials ◽  
2019 ◽  
Vol 12 (9) ◽  
pp. 1361
Author(s):  
Lilin Hu ◽  
Zhu Miao ◽  
Yang Zhang ◽  
Hai Zhang ◽  
Hairui Yang
Keyword(s):  
High Speed ◽  
Deposition Time ◽  
Windward Side ◽  
Leeward Side ◽  
Rotation Effect ◽  
Nanoparticle Deposition ◽  
Numerical Assessment ◽  
O2 Concentration ◽  
Rotating Surface ◽  
Cfd Method

The effect of rotation of the stagnation surface on the nanoparticle deposition in the flame stabilizing on a rotating surface (FSRS) configuration was numerically assessed using CFD method. The deposition properties including particle trajectories, deposition time, temperature and surrounding O2 concentration between the flame and stagnation surface were examined. The results revealed that although flame position is insensitive to the surface rotation, the temperature and velocity fields are remarkably affected, and the deposition properties become asymmetric along the burner centerline when the surface rotates at a fast speed (rotational speed ω ≥ 300 rpm). Particles moving on the windward side have similar deposition properties when the surface rotates slowly, but the off-center particles on the leeward side have remarkable longer deposition time, lower deposition temperature, and lower surrounding O2 concentration, and they even never deposit on the surface when the surface rotates at a high speed. The rotation effect of the stagnation surface can be quantitatively described by an analogous Karlovitz number (Ka’), which is defined as the ratio of characteristic residence time of moving surface to the aerodynamics time induced by flame stretch. For high quality semiconducting metal oxide (SMO) films, it is suggested that Ka’ ≥ 1 should be kept.

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