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.

scholarly journals INFLUENCE OF FOREST SHELTER BELTS ON THE WATER CONSUMPTION INDICATOR OF SPRING BARLEY

2020 ◽  
Vol 10 (1) ◽  
pp. 69-75
Author(s):  
Ol'ga Ruleva ◽  
Elena Seminchenko
Keyword(s):  
Water Consumption ◽  
Spring Barley ◽  
Grain Filling ◽  
Forest Belt ◽  
Factors Affecting ◽  
Functional Relationships ◽  
Shelter Belts ◽  
Forest Belts ◽  
The Impact ◽  
Forest Shelter Belts

The article presents research materials on the impact of shelterbelts on the growth and development of spring barley. It has been established that the reserves of productive moisture on the inter-strip cell are distributed unevenly and vary depending on the distance from the forest belt. The greatest spring moisture reserve (in the conditions of agroforestry) accumulates in the zone from 5H to 15N from forest shelter belts. The yield of spring barley in the inter-strip space is formed depending on the distance to the forest belt. The distance from the forest belt and its influence on the phases of plant development has been critically evaluated based on mathematical modeling and empirical data. Data on the average daily moisture consumption of barley plants by development phases have been processed to clarify the factors affecting the formation of the crop. Functional relationships have been obtained using STATICTIKA computer program. High correlation between the distance from the forest belt and the phases of barley has been found: tube forming (R = -0.94), booting stage (R = -0.93), blooming period (R = -0.93). The forecast for barley development in the phases of grain filling and ripening is slightly lower and amounted to R = -0.89. The relationship between the coefficient of water consumption and the distance from the forest belt has not been identified. The analysis has showed the influence of the barley water consumption coefficient depending on the distance to the forest belts on the vegetation phases of this crop. The results of the study indicate the important role of forest belts

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.

Impact of coastal East Antarctic ice rises on surface mass balance: insights from observations and modelling

2020 ◽  
Author(s):  
Thore Kausch ◽  
Stef Lhermitte ◽  
Jan T.M. Lenaerts ◽  
Nander Wever ◽  
Mana Inoue ◽  
...  
Keyword(s):  
Mass Balance ◽  
Wind Erosion ◽  
Ice Core ◽  
Ice Cores ◽  
Snow Accumulation ◽  
Windward Side ◽  
Leeward Side ◽  
Surface Mass Balance ◽  
Surface Mass ◽  
Local Erosion

<p>About 20% of all snow accumulation in Antarctica occurs on the ice shelfs and ice rises, locations within the ice shelf where the ice is locally grounded on topography. These ice rises largely control the spatial surface mass balance (SMB) distribution by inducing snowfall variability due to orographic uplift and by inducing wind erosion due altering the wind conditions. Moreover these ice rises buttress the ice flow and represent an ideal drilling locations for ice cores.</p><p>In this study we assess the connection between snowfall variability and wind erosion to provide a better understanding of how ice rises impact SMB variability, how well this is captured in the regional atmospheric climate model RACMO, and the implications of this SMB variability for ice rises as an ice core drilling side. By combining ground penetrating radar profiles from two ice rises in Dronning Maud Land with ice core dating we reconstruct spatial and temporal SMB variations across both ice rises from 1982 to 2017. Subsequently, the observed SMB is compared with output from RACMO, SnowModel to quantify the contribution of the different processes that control the spatial SMB variability across the ice rises. Finally, the observed SMB is compared with Sentinel-1 backscatter data to extrapolate spatial SMB trends over larger areas.</p><p>Our results show snowfall-driven differences of up to ~ 0.24 m w.e./yr between the windward and the leeward side of both ice rises as well as a local erosion driven minimum at the peak of the ice rises. RACMO captures the snowfall-driven differences, but overestimates their magnitude, whereas the erosion on the peak can be reproduced by SnowModel with RACMO forcing. Observed temporal variability of the average SMBs calculated for 4 time intervals in the 1982-2017 range are low at the peak of the easternmost ice rise (~ 0.03 m w.e./yr), while being three times higher (~ 0.1 m w.e./yr) on the windward side of the ice rise. This implicates that at the peak of the ice rise, higher snowfall, driven by regional processes, such as orographic uplift, is balanced out by local erosion.  Comparison of the observed SMB gradients with Sentinel-1 data finally shows the potential of SAR satellite observations to represent spatial variability in SMB across ice shelves and ice rises.</p>

Role of Advection on the Evolution of Near-Surface Temperature and Wind in Urban-Aware Simulations

2020 ◽  
Author(s):  
Pallav Ray ◽  
Haochen Tan ◽  
Mukul Tewari ◽  
James Brownlee ◽  
R. S. Ajayamohan ◽  
...  
Keyword(s):  
Surface Temperature ◽  
Urban Areas ◽  
Single Layer ◽  
Windward Side ◽  
Leeward Side ◽  
Land Use Patterns ◽  
Near Surface ◽  
Horizontal Advection ◽  
The City

AbstractThe role of advection of heat and momentum on the evolution of near-surface temperature and wind is evaluated in urban-aware simulations over Houston under dry conditions on a light-wind day. Two sets of experiments, each consisting of four simulations using different planetary boundary layer (PBL) schemes, were conducted over 48 hours using the default urban scheme (BULK) and the single-layer urban canopy model (SLUCM) available within the Weather Research and Forecasting (WRF) model. We focus on understanding and quantifying the role played by temperature and momentum advection, particularly on the windward and leeward sides of the city. Previous studies have largely ignored any quantitative analysis of impacts from the advection of momentum over an urban area.The horizontal advection of temperature was found to be more important in the BULK because of the larger surface temperature gradient caused by warmer surface temperatures over urban areas than in the SLUCM. An analysis of the momentum budget shows that horizontal advection of zonal and meridional momentum plays a prominent role during the period of peak near-surface winds, and this effect is more pronounced in the windward side of the city. The local tendency in peak winds in the leeward side lags that in the windward side by about 1-2 hours, similar to the lag found in horizontal momentum advection. The sensitivity of the results to different urban and PBL schemes was explored. The results imply that representation and influence of land-use patterns via sophisticated urban parameterizations generates locally driven winds that best resemble observations.

The impact of insolation, greenhouse gas forcing and ocean circulation changes on glacial inception

The Holocene ◽  
2011 ◽  
Vol 21 (5) ◽  
pp. 803-817 ◽  
Author(s):  
G. Vettoretti ◽  
W.R. Peltier
Keyword(s):  
Snow Cover ◽  
Greenhouse Gas ◽  
Ocean Circulation ◽  
High Latitude ◽  
Goodness Of Fit ◽  
Decadal Variability ◽  
Snow Accumulation ◽  
High Northern Latitude ◽  
The Future ◽  
The Impact

In this study we employ the NCAR CCSM3 coupled model to investigate the onset of high northern latitude perennial snow cover. Two periods of Earth’s insolation history, that of the pre-industrial period and that of 116 ka before present (BP), are used as benchmarks in an investigation of the influences of interglacial greenhouse gas (GHG) concentration and insolation upon the occurrence of permanent summer snow cover. An additional two experiments at 10 ka and 51 ka into the future (AP) using a typical interglacial GHG level are used to investigate the length of the current interglacial. Results from this set of multicentury sensitivity experiments demonstrate the relative importance of forcings due to insolation and atmospheric greenhouse gases at the millennial scale, and of Atlantic ocean overturning strength (AMOC) at the century scale. We find that while areas of perennial snow cover are sensitive to GHG concentrations, they are much more sensitive to the contemporaneous insolation regime. The goodness of fit of the climatology of the control model to the modern observed climatology is found to influence the modeling results. While there is a strong correlation between AMOC decadal variability and high latitude surface temperature in our control climates, we find little change in AMOC strength during our simulations of 116 ka BP climate nor do we find significant correlation between high latitude snow accumulation and the AMOC. Both the 10 ka AP and 51 ka AP future simulations produce inception events which are much stronger than that of the equivalent pre-industrial simulation. The simulation of inception at 10 ka into the future suggests a maximum duration of the current interglacial of approximately 20 ka in the absence of modern anthropogenic forcing.

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 Importance of Near-Surface Winter Precipitation Processes in Complex Alpine Terrain

2019 ◽  
Vol 20 (2) ◽  
pp. 177-196 ◽  
Author(s):  
Franziska Gerber ◽  
Rebecca Mott ◽  
Michael Lehning
Keyword(s):  
Winter Precipitation ◽  
Snow Accumulation ◽  
Windward Side ◽  
Leeward Side ◽  
Small Scale ◽  
Orographic Precipitation ◽  
Near Surface ◽  
Simulated Precipitation ◽  
Snow Precipitation ◽  
Precipitation Enhancement

Abstract In this study, near-surface snow and graupel dynamics from formation to deposition are analyzed using WRF in a large-eddy configuration. The results reveal that a horizontal grid spacing of ≤50 m is required to resolve local orographic precipitation enhancement, leeside flow separation, and thereby preferential deposition. At this resolution, precipitation patterns across mountain ridges show a high temporal and spatial variability. Simulated and observed event-mean snow precipitation across three mountain ridges in the upper Dischma valley (Davos, Switzerland) for two precipitation events show distinct patterns, which are in agreement with theoretical concepts, such as small-scale orographic precipitation enhancement or preferential deposition. We found for our case study that overall terrain–flow–precipitation interactions increase snow accumulation on the leeward side of mountain ridges by approximately 26%–28% with respect to snow accumulation on the windward side of the ridge. Cloud dynamics and mean advection may locally increase precipitation on the leeward side of the ridge by up to about 20% with respect to event-mean precipitation across a mountain ridge. Analogously, near-surface particle–flow interactions, that is, preferential deposition, may locally enhance leeward snow precipitation on the order of 10%. We further found that overall effect and relative importance of terrain–flow–precipitation interactions are strongly dependent on atmospheric humidity and stability. Weak dynamic stability is important for graupel production, which is an essential component of solid winter precipitation. A comparison to smoothed measurements of snow depth change reveals a certain agreement with simulated precipitation across mountain ridges.

scholarly journals Impact of Surface Albedo Assimilation on Snow Estimation

2020 ◽  
Vol 12 (4) ◽  
pp. 645 ◽  
Author(s):  
Sujay Kumar ◽  
David Mocko ◽  
Carrie Vuyovich ◽  
Christa Peters-Lidard
Keyword(s):  
Snow Cover ◽  
Land Surface ◽  
Snow Depth ◽  
Surface Albedo ◽  
Land Surface Model ◽  
Snow Accumulation ◽  
High Plains ◽  
Surface Model ◽  
Fractional Snow Cover ◽  
The Impact

Surface albedo has a significant impact in determining the amount of available net radiation at the surface and the evolution of surface water and energy budget components. The snow accumulation and timing of melt, in particular, are directly impacted by the changes in land surface albedo. This study presents an evaluation of the impact of assimilating Moderate Resolution Imaging Spectroradiometer (MODIS)-based surface albedo estimates in the Noah multi-parameterization (Noah-MP) land surface model, over the continental US during the time period from 2000 to 2017. The evaluation of simulated snow depth and snow cover fields show that significant improvements from data assimilation (DA) are obtained over the High Plains and parts of the Rocky Mountains. Earlier snowmelt and reduced agreements with reference snow depth measurements, primarily over the Northeast US, are also observed due to albedo DA. Most improvements from assimilation are observed over locations with moderate vegetation and lower elevation. The aggregate impact on evapotranspiration and runoff from assimilation is found to be marginal. This study also evaluates the relative and joint utility of assimilating fractional snow cover and surface albedo measurements. Relative to surface albedo assimilation, fractional snow cover assimilation is found to provide smaller improvements in the simulated snow depth fields. The configuration that jointly assimilates surface albedo and fractional snow cover measurements is found to provide the most beneficial improvements compared to the univariate DA configurations for surface albedo or fractional snow cover. Overall, the study also points to the need for improving the albedo formulations in land surface models and the incorporation of observational uncertainties within albedo DA configurations.

Snow accumulation and ablation in disturbed mountain spruce forest in West Tatra Mts

Biologia ◽  
2014 ◽  
Vol 69 (11) ◽  
Author(s):  
Martin Bartík ◽  
Roman Sitko ◽  
Marek Oreňák ◽  
Juraj Slovik ◽  
Jaroslav Škvarenina
Keyword(s):  
Snow Cover ◽  
Open Space ◽  
Snow Water Equivalent ◽  
Reference Value ◽  
Research Area ◽  
Snow Accumulation ◽  
Snow Density ◽  
Tatra Mts ◽  
Snow Water ◽  
The Impact

AbstractIn the presented paper we deal with the impact of the mature spruce stand on the accumulation and melting of snow cover at Červenec research area located in the Western Tatras at an elevation of 1420 m a.s.l. The work analyses the data obtained from the monitoring of snow cover during the period 2009–2014 (6 seasons). Since the season 2012/2013 the measurements have been also performed in a dead part of the stand and in a meadow. The results proved significant impact of the spruce stand on hydro-physical characteristics of snow cover — snow water equivalent, snow density, as well as on their change due to the dieback of the stand. The data measured at individual locations (open space in the forest, open meadow area, living and dead forest) were tested with the paired t-test for the significance of average differences. Average snow water equivalent in the living forest, dead forest and meadow was 42%, 47% and 83% of the reference value measured at the open space in the forest, respectively. The process of snow accumulation and melting was fastest at the open space, followed by the dead forest. In the living forest, the processes were the slowest.

The Numerical Simulation of the Impact on the Hangzhou Bay Bridge Offshore Platform and the Sightseeing Tower

2012 ◽  
Vol 532-533 ◽  
pp. 352-356
Author(s):  
Hua Bai ◽  
Fang Liang Wang ◽  
Yu Li
Keyword(s):  
Numerical Simulation ◽  
Wind Tunnel ◽  
Surface Pressure ◽  
Wind Tunnel Test ◽  
Offshore Platform ◽  
Wind Pressure ◽  
Windward Side ◽  
Hangzhou Bay ◽  
Leeward Side ◽  
The Impact

In this paper, the distribution of surface wind pressure and wind speed of Hangzhou bay bridge, offshore platform and sightseeing tower is numerically simulated based on Fluent. Two turbulence models, standard k ε model and Realizable k ε model, are used. The influence of the wind pressure distribution of the offshore platform and sightseeing tower by Hangzhou bay bridge is also analyzed. And the detailed comparison between numerical simulation and wind tunnel test is given. Results show that the impact of Hangzhou bay bridge on platform and sightseeing tower occurs mainly with the angle of the wind less than 450. When the angle of the wind is more than 450, the impact is little. The upper of the sightseeing tower does not almost suffer the effect of other buildings. The surface pressure of the platform changes from 5% to 15% between under bridge and under non-bridge condition. The surface pressure of sightseeing tower changes from 0.05% to 3%. The influence on the platform by the bridge is significant but not significant on the sightseeing tower. The simulation results of the tower and mast structure given by both standard k ε model and Realizable k ε model find that the windward side is ideal; the crosswind side is the best; the leeward side is less than ideal. By contrast, the Realizable k ε model is a closer correlation with wind tunnel test than standard k ε model.

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