RESEARCH RESULTS OF THE MODIFIED WORKING TOOL OF THE COMBINED ROTARY MOWER

Currently, there are practically no mechanization tools on the market that combine grass removal (mowing) and the levelling loosening of the upper soil layer, while cutting the root systems contained in the soil in one pass. The purpose of the study was to provide a theoretical rationale of the modifi ed design of the working tool of the combined rotary mower, as well as to conduct its laboratory and fi eld studies. Complex theoretical, laboratory and fi eld studies were carried out using the equipment of the Department of Technological and Transport Machines and Complexes, the Department of Technology of Processing and Storage of Agricultural Products of Tver State Agricultural Academy and recognized methods of experimental research. In the course of theoretical studies, the main parameters of the new working tool were determined, which enabled two technological processes to be carried out in one pass: grass mowing and cutting with loosening of the top soil layer (0…10 cm). On the basis of the obtained data, a workable model of the working tool was designed. When tested in laboratory conditions, regardless of the operating modes and the initial state of the cultivated soil, improved agrophysical properties were observed in terms of absolute humidity and saturation with root residues. It was found that the most optimal level of absolute humidity for the impact of the working tool on soils of light-loamy granulometric composition was 20%, while the best structural and density indicators were observed at all values of soil saturation with root residues; thgey averaged 2.24 units and 1.26 g/cm3. It has been established that at low operating speeds, it is advisable to use a higher rotation speed of the working tool (at 150 rpm), at the same time, with an increase in speed, the speed of rotation should be reduced (to 110 rpm). As a result of fi eld experiments, convincing data were obtained on the feasibility of using a new working tool that provides eff ective mowing of grassland vegetation (the purity of the stem cut is 95.6%) and loosening of the surface layer of the soil (0…10 cm), increasing the structural coeffi cient by 26.8% while optimizing the density and grinding of root systems. The next stages of the study include developing and manufacturing a workable design of a combined rotary mower prototype that ensures the optimal energy intensity of performance and the required quality of technological processes.

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The Impact of Error Accounting in a Bayesian Approach to Calibrating Modeled Turbulent Fluxes in an Open-Canopy Forest

Journal of Hydrometeorology ◽

10.1175/jhm-d-17-0030.1 ◽

2017 ◽

Vol 18 (7) ◽

pp. 2029-2042

Author(s):

Tony E. Wong ◽

William Kleiber ◽

David C. Noone

Keyword(s):

Markov Chain ◽

Land Surface ◽

Hydrological Modeling ◽

Soil Layer ◽

Turbulent Fluxes ◽

Surface Model ◽

Model Parameters ◽

Top Soil ◽

The Impact ◽

Calibration Approach

Abstract Land surface models are notorious for containing many parameters that control the exchange of heat and moisture between land and atmosphere. Properly modeling the partitioning of total evapotranspiration (ET) between transpiration and evaporation is critical for accurate hydrological modeling, but depends heavily on the treatment of turbulence within and above canopies. Previous work has constrained estimates of evapotranspiration and its partitioning using statistical approaches that calibrate land surface model parameters by assimilating in situ measurements. These studies, however, are silent on the impacts of the accounting of uncertainty within the statistical calibration framework. The present study calibrates the aerodynamic, leaf boundary layer, and stomatal resistance parameters, which partially control canopy turbulent exchange and thus the evapotranspiration flux partitioning. Using an adaptive Metropolis–Hastings algorithm to construct a Markov chain of draws from the joint posterior distribution of these resistance parameters, an ensemble of model realizations is generated, in which latent and sensible heat fluxes and top soil layer temperature are optimized. A set of five calibration experiments demonstrate that model performance is sensitive to the accounting of various sources of uncertainty in the field observations and model output and that it is critical to account for model structural uncertainty. After calibration, the modeled fluxes and top soil layer temperature are largely free from bias, and this calibration approach successfully informs and characterizes uncertainty in these parameters, which is essential for model improvement and development. The key points of this paper are 1) a Markov chain Monte Carlo calibration approach successfully improves modeled turbulent fluxes; 2) ET partitioning estimates hinge on the representation of uncertainties in the model and data; and 3) despite these inherent uncertainties, constrained posterior estimates of ET partitioning emerge.

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The impact of morphometric characteristics of plants self-pollinated sunflower lines on its lodging

Oil Crops Scientific and technical bulletin of All-Russian Research Insitute of Oil Crops by the name of Pustovoit V S ◽

10.25230/2412-608x-2020-4-184-3-11 ◽

2020 ◽

Vol 4 (184) ◽

pp. 3-11

Author(s):

B.N. Bochkaryov ◽

◽

N.V. Medvedeva ◽

E.N. Ryzhenko ◽

◽

...

Keyword(s):

Root System ◽

Lateral Roots ◽

Root Systems ◽

Morphometric Characteristics ◽

Main Root ◽

Lodging Resistance ◽

Oil Crops ◽

Russian Research Institute ◽

Top Soil ◽

The Impact

We carried out the research in 2018-2019 at the experimental station of V.S. Pustovoit All-Russian Research Institute of Oil Crops. The aim of the research is to study the effect of certain morphometric characteristics of the overground part of plants and the architectonics of the root system on the sunflower lodging. We found significant differences in the architectonics of root systems in 17 maternal lines of sunflower: we identified three morphotypes, differing in the number and thickness of lateral roots of the first and subsequent orders, located in the top soil. We identified the sunflower lines that have a root system with a well-developed main root and many lateral roots of various orders (type A), lines with a normally developed main root and a small number of lateral roots (type B), and lines with a poorly developed main root and few lateral roots in top soil (type C). We identified the presence of both low and high lodging in sunflower lines with different types of root systems. At the same time, there is a tendency towards higher lodging in lines with root system types B and C. The line SL12 3660 showed the maximum lodging resistance during two years of observations. It may be of interest for further work as a possible source of a lodging resistance trait.

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Investigating the Influence of Biochar Particle Size and Depth of Placement on Nitrous Oxide (N2O) Emissions from Simulated Urine Patches

Agriculture ◽

10.3390/agriculture8110175 ◽

2018 ◽

Vol 8 (11) ◽

pp. 175

Author(s):

Ainul Mahmud ◽

Marta Camps-Arbestain ◽

Mike Hedley

Keyword(s):

Particle Size ◽

Nitrous Oxide ◽

Soil Column ◽

Soil Layer ◽

Nitrous Oxide Emissions ◽

N2o Emissions ◽

Top Soil ◽

The Impact ◽

Soil Inversion

The use of biochar reduces nitrous oxide (N2O) emissions from soils under specific conditions yet the mechanisms through which interactions occur are not fully understood. The objectives of this glasshouse study were to investigate the effect of (i) biochar particle size, and (ii) the impact of soil inversion—through simulated mouldboard ploughing—on N2O emissions from soils to which cattle urine was applied. Pine biochar (550 °C) with two different particle sizes (<2 mm and >4 mm) was mixed either into the top soil layer at the original 0–10 cm depth in the soil column or at 10–20 cm depth by inverting the top soil to simulate ploughing. Nitrous oxide emissions were monitored for every two to three days, up to seven weeks during the summer trial and measurements were repeated during the autumn trial. We found that the use of large particle size biochar in the inverted soil had significant impact on increasing the cumulative N2O emissions in autumn trial, possibly through changes in the water hydraulic conductivity of the soil column and increased water retention at the boundary between soil layers. This study thus highlights the importance of the role of biochar particle size and the method of biochar placement on soil physical properties and the implications of these on N2O emissions.

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THE INFLUENCE OF PLANT LIFTER OPERATING MODES ON THE DIGGING QUALITY OF PLANTING MATERIAL

Forestry Engineering Journal ◽

10.34220/issn.2222-7962/2020.1/16 ◽

2020 ◽

Vol 10 (1) ◽

pp. 203-208

Author(s):

Igor' Kazakov

Keyword(s):

Root System ◽

Soil Layer ◽

Root Systems ◽

Operating Speed ◽

Considerable Effort ◽

Operating Modes ◽

Planting Material ◽

Forest Nurseries ◽

Working Bodies

One of the important indicators of the quality of planting material grown in forest nurseries is preservation of roots and the amount of soil remaining on the root system of plants when they are excavated. Machines used in forest nurseries for digging planting material do not fully meet these requirements, since soil layer is not sufficiently loosened and soil is not separated from the root systems of plants. In addition, considerable effort is required to extract plants from the soil, and part of the roots is cut off. Modern plant lifters with active working bodies enable to separate the soil from the root systems of plants and ensure safety of the required amount on them, reducing the effort to extract plants from the soil. The article presents the results of studies of the influence of plant lifter operating modes on the quality of planting material harvesting, on the basis of which the rational oscillation frequency of the levers and beats within 675 counts/min is substantiated when applying one oscillation of 5.4 cm/count and operating speed 2.2 km/h. These operation modes of plant lifter ensure the preservation of soil on the root system of enlarged spruce seedlings in the amount of 136.2 g and allowable effort to remove them from the soil within 36.4 N.

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Comparative study of the impact of two mechanical perforation densities on the behavior of a sandy soil

Progress in Agricultural Engineering Sciences ◽

10.1556/progress.8.2012.2 ◽

2012 ◽

Vol 8 (1) ◽

pp. 37-48

Author(s):

S. Chehaibi ◽

K. Abrougui ◽

F. Haouala

Keyword(s):

Soil Water ◽

Sandy Soil ◽

Water Infiltration ◽

Cone Penetration ◽

Initial State ◽

Soil Water Infiltration ◽

Good Improvement ◽

The Impact ◽

Positive Effect ◽

Resistance To Penetration

The effects of mechanical perforation densities by extracting soil cores through an aerator Vertidrain with a working width of 1.6 m and equipped with hollow tines spaced of 65 mm, were studied on a sandy soil of a grassy sward in the Golf Course El Kantaoui in Sousse (Tunisia). The mechanical aeration was performed at two densities: 250 and 350 holes/m2. The cone penetration resistance and soil water infiltration were measured. These parameters were performed at initial state before aeration (E0) and then on the 10th, 20th and 30th day after aeration. These results showed that perforation density of 350 holes/m2 had a positive effect on the soil by reducing its cone resistance to penetration compared to the initial state (Rp = 14.8 daN/cm2). At 5 cm depth the decrease in resistance to penetration was 34% and 43% on the 10th and 20th day after aeration, respectively. However, on the 30th day after aeration the soil resistance to penetration tended to grow and its value compared to the initial state decreased only by 21 and 26%, respectively, at 5 and 15 cm of depth only by 10% and 9% with 250 holes/m2 density. The soil water infiltration made a good improvement after aeration compared to the initial state. This parameter increased from 4.8 cm/h to 8.3, 10.9 and 13.1 cm/h with 250 holes/m2 density and to 10, 12.9 and 14.8 cm/h with 350 holes/m2 density on the 10th, 20th and 30th day following the aeration.

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Prospects of spring wheat cultivation in the conditions of arid Volga region

The Agrarian Scientific Journal ◽

10.28983/asj.y2020i5pp28-33 ◽

2020 ◽

pp. 28-33

Author(s):

Valery Genadievich Popov ◽

Andrey Vladimirovich Panfilov ◽

Yuriy Vyacheslavovich Bondarenko ◽

Konstantin Mikhailovich Doronin ◽

Evgeny Nikolaevih Martynov ◽

...

Keyword(s):

Spring Wheat ◽

Soil Layer ◽

Weather Conditions ◽

Volga Region ◽

Mineral Fertilizers ◽

Climate Conditions ◽

Wheat Cultivation ◽

Forest Belts ◽

Clear Differentiation ◽

The Impact

The article analyzes the experience of the impact of the system of forest belts and mineral fertilizers on the yield of spring wheat, including on irrigated lands. Vegetation irrigation is designed to maintain the humidity of the active soil layer from germination to maturation at the lower level of the optimum-70-75%, and in the phases of tubulation-earing - flowering - 75-80% NV. However, due to the large differences in zones and microzones of soil and climate conditions and due to the weather conditions of individual years, wheat irrigation regimes require a clear differentiation. In the Volga region in the dry autumn rainfalls give the norm of 800-1000 m3/ha, and in saline soils – 1000-1300 and 3-4 vegetation irrigation at tillering, phases of booting, earing and grain formation the norm 600-650 m3/ha. the impact of the system of forest belts, mineral fertilizers on the yield of spring wheat is closely tied to the formation of microclimate at different distances from forest edges.

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Organic mulching promotes soil organic carbon accumulation to deep soil layer in an urban plantation forest

Forest Ecosystems ◽

10.1186/s40663-020-00278-5 ◽

2021 ◽

Vol 8 (1) ◽

Author(s):

Xiaodan Sun ◽

Gang Wang ◽

Qingxu Ma ◽

Jiahui Liao ◽

Dong Wang ◽

...

Keyword(s):

Organic Carbon ◽

Soil Organic Carbon ◽

Carbon Content ◽

Fine Roots ◽

Soil Layer ◽

Carbon Accumulation ◽

Bulk Soil ◽

Organic Mulch ◽

The Impact ◽

Soc Fractions

Abstract Background Soil organic carbon (SOC) is important for soil quality and fertility in forest ecosystems. Labile SOC fractions are sensitive to environmental changes, which reflect the impact of short-term internal and external management measures on the soil carbon pool. Organic mulching (OM) alters the soil environment and promotes plant growth. However, little is known about the responses of SOC fractions in rhizosphere or bulk soil to OM in urban forests and its correlation with carbon composition in plants. Methods A one-year field experiment with four treatments (OM at 0, 5, 10, and 20 cm thicknesses) was conducted in a 15-year-old Ligustrum lucidum plantation. Changes in the SOC fractions in the rhizosphere and bulk soil; the carbon content in the plant fine roots, leaves, and organic mulch; and several soil physicochemical properties were measured. The relationships between SOC fractions and the measured variables were analysed. Results The OM treatments had no significant effect on the SOC fractions, except for the dissolved organic carbon (DOC). OM promoted the movement of SOC to deeper soil because of the increased carbon content in fine roots of subsoil. There were significant correlations between DOC and microbial biomass carbon and SOC and easily oxidised organic carbon. The OM had a greater effect on organic carbon fractions in the bulk soil than in the rhizosphere. The thinnest (5 cm) mulching layers showed the most rapid carbon decomposition over time. The time after OM had the greatest effect on the SOC fractions, followed by soil layer. Conclusions The frequent addition of small amounts of organic mulch increased SOC accumulation in the present study. OM is a potential management model to enhance soil organic matter storage for maintaining urban forest productivity.

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Cumulative Effects of Particulate Matter Pollution and Meteorological Variables on the Risk of Influenza-Like Illness

Viruses ◽

10.3390/v13040556 ◽

2021 ◽

Vol 13 (4) ◽

pp. 556

Author(s):

Kacper Toczylowski ◽

Magdalena Wietlicka-Piszcz ◽

Magdalena Grabowska ◽

Artur Sulik

Keyword(s):

Particulate Matter ◽

Respiratory Infections ◽

Nonlinear Models ◽

Absolute Humidity ◽

Influenza Viruses ◽

Meteorological Variables ◽

Exponential Relationship ◽

Influenza Like Illness ◽

Air Temperatures ◽

The Impact

The cold season is usually accompanied by an increased incidence of respiratory infections and increased air pollution from combustion sources. As we are facing growing numbers of COVID-19 cases caused by the novel SARS-CoV-2 coronavirus, an understanding of the impact of air pollutants and meteorological variables on the incidence of respiratory infections is crucial. The incidence of influenza-like illness (ILI) can be used as a close proxy for the circulation of influenza viruses. Recently, SARS-CoV-2 has also been detected in patients with ILI. Using distributed lag nonlinear models, we analyzed the association between ILI, meteorological variables and particulate matter concentration in Bialystok, Poland, from 2013–2019. We found an exponential relationship between cumulative PM2.5 pollution and the incidence of ILI, which remained significant after adjusting for air temperatures and a long-term trend. Pollution had the greatest effect during the same week, but the risk of ILI was increased for the four following weeks. The risk of ILI was also increased by low air temperatures, low absolute humidity, and high wind speed. Altogether, our results show that all measures implemented to decrease PM2.5 concentrations would be beneficial to reduce the transmission of SARS-CoV-2 and other respiratory infections.

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Earthworm Abundance Changes Depending on Soil Management Practices in Slovenian Vineyards

Agronomy ◽

10.3390/agronomy11061241 ◽

2021 ◽

Vol 11 (6) ◽

pp. 1241

Author(s):

Stanko Vršič ◽

Marko Breznik ◽

Borut Pulko ◽

Jesús Rodrigo-Comino

Keyword(s):

Management Practices ◽

Human Impacts ◽

Soil Layer ◽

Soil Management ◽

Weather Conditions ◽

Soil Tillage ◽

Soil Biodiversity ◽

Straw Mulch ◽

Green Cover ◽

The Impact

Earthworms are key indicators of soil quality and health in vineyards, but research that considers different soil management systems, especially in Slovenian viticultural areas is scarce. In this investigation, the impact of different soil management practices such as permanent green cover, the use of herbicides in row and inter-row areas, use of straw mulch, and shallow soil tillage compared to meadow control for earthworm abundance, were assessed. The biomass and abundance of earthworms (m2) and distribution in various soil layers were quantified for three years. Monitoring and a survey covering 22 May 2014 to 5 October 2016 in seven different sampling dates, along with a soil profile at the depth from 0 to 60 cm, were carried out. Our results showed that the lowest mean abundance and biomass of earthworms in all sampling periods were registered along the herbicide strip (within the rows). The highest abundance was found in the straw mulch and permanent green cover treatments (higher than in the control). On the plots where the herbicide was applied to the complete inter-row area, the abundance of the earthworm community decreased from the beginning to the end of the monitoring period. In contrast, shallow tillage showed a similar trend of declining earthworm abundance, which could indicate a deterioration of soil biodiversity conditions. We concluded that different soil management practices greatly affect the soil’s environmental conditions (temperature and humidity), especially in the upper soil layer (up to 15 cm deep), which affects the abundance of the earthworm community. Our results demonstrated that these practices need to be adapted to the climate and weather conditions, and also to human impacts.

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Influence of Slope Direction on the Soil Seed Bank and Seedling Regeneration of Castanopsis hystrix Seed Rain

Forests ◽

10.3390/f12040500 ◽

2021 ◽

Vol 12 (4) ◽

pp. 500

Author(s):

Zong Zhao ◽

Yong Liu ◽

Hongyan Jia ◽

Wensheng Sun ◽

Angang Ming ◽

...

Keyword(s):

Seed Bank ◽

Temporal Dynamics ◽

Soil Seed Bank ◽

Soil Layer ◽

Seed Rain ◽

Seed Vigor ◽

Study Results ◽

The Impact ◽

Mature Seeds

Objective: To investigate the impact of different slope directions on the quantity and quality of the soil seed bank and seedling germination process of Castanopsis hystrix plantations. Method: Fixed sample plots in forest stands of Castanopsis hystrix were established on different slope directions (sunny slope, semi-sunny slope, semi-shady slope, and shady slope). The characteristics of the forest stand were investigated, and per-wood scaling was carried out. The temporal dynamics of the seed rain and seed bank were quantified using seed rain collectors and by collecting soil samples from different depths. The quantity and quality of the seeds were determined, and the vigor of mature seeds was measured throughout the study. Results: (1) The diffusion of Castanopsis hystrix seed rain started in mid-September, reached its peak from late October to early November, and ended in mid-December. (2) The dissemination process, occurrence time, and composition of the seed rain varied between the different slope directions. The seed rain intensity on the semi-sunny slope was the highest (572.75 ± 9.50 grains∙m−2), followed by the sunny slope (515.60 ± 10.28 grains∙m−2), the semi-shady slope (382.13 ± 12.11 grains∙m−2), and finally the shady slope (208.00 ± 11.35 grains∙m−2). The seed rain on the sunny slope diffused earliest and lasted the longest, while the seed rain on the shady slope diffused latest and lasted the shortest time. Seed vigor and the proportion of mature seeds within the seed rain were greatest on the semi-sunny slope, followed by the sunny slope, semi-shady slope, and the shady slope. (3) From the end of the seed rain to August of the following year, the amount of total reserves of the soil seed banks was highest on the semi-sunny slope, followed by the sunny slope then the semi-shady slope, and it was the lowest on the shady slope. The amount of mature, immature, gnawed seeds and seed vigor of the soil seed bank in various slope directions showed a decreasing trend with time. The seeds of the seed bank in all slope directions were mainly distributed in the litter layer, followed by the 0–2 cm humus layer, and only a few seeds were present in the 2–5 cm soil layer. (4) The seedling density of Castanopsis hystrix differed significantly on the different slope directions. The semi-sunny slope had the most seedlings, followed by the sunny slope, semi-shady slope, and the shady slope. Conclusions: The environmental conditions of the semi-sunny slope were found to be most suitable for the seed germination and seedling growth of Castanopsis hystrix, and more conducive to the regeneration and restoration of its population.

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