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Plants respond to their environment through adaptations; for example, earthworms that create heterogeneity can lead to local adaptation of roots. This research identifies a mechanism to explain plant responses to earthworms and how these mechanisms are related. Our results show that tillage intensity has a negative effect on earthworms and root volume. The mean root volume and earthworm biomass under conventional tillage were lower than in reduced tillage and no-tillage. The root volume and the root diameter in the field with residues were higher than in the field without residues, while the root length density and earthworm biomass in the field with residues were lower than in the field without residues. This study demonstrates that the mean of the root length density and biomass of the earthworms were higher in sandy loam than in loam. Therefore, sand content had a positive effect on root length density (R2 = 0.72, p < 0.01) and earthworm biomass (R2 = 0.74, p < 0.01). Earthworm biomass had a positive effect on root volume (R2 = 0.54, p < 0.05) and length density (R2 = 0.88, p < 0.01). This confirms our hypothesis on the effect of earthworms on root systems. [ABSTRACT FROM AUTHOR]

Self-localization and pose registration are required for sound operation of next generation autonomous vehicles under uncertain environments. Thus, precise localization and mapping are crucial tasks in odometry, planning and other downstream processing. In order to reduce information loss in preprocessing, we propose leveraging LiDAR-based localization and mapping (LOAM) with point cloud-based deep learning instead of convolutional neural network (CNN) based methods that require cylindrical projection. The normal distribution transform (NDT) algorithm is then used to refine the former coarse pose estimation from the deep learning model. The results demonstrate that the proposed method is comparable in performance to recent benchmark studies. We also explore the possibility of using Product Quantization to improve NDT internal neighborhood searching by using high-level features as fingerprints. [ABSTRACT FROM AUTHOR]

Lamellae are a morphological feature of soils that can be observed visually, as horizontal layers or bands of varying quantity, thickness and depth in the soil profile. They are found frequently in soils from the central-west region of the province of Córdoba (Argentina). The objectives of this study are: 1) to identify the presence of lamellae in an area of the province of Córdoba, 2) to characterize their morphological aspects, and 3) to evaluate their effect on soil permeability. The existence of lamellae was confirmed in 195 profiles in the districts of Achiras, Río Cuarto, and Tegua (Córdoba, Argentina). In 54 profiles of Haplustolls, the quantity, thickness, shape, and depth of lamellae were registered. Samples were taken both from the pure lamella profile and from positions above and below it. Particle size distribution, organic matter, and saturated hydraulic conductivity were measured. The number of lamellae per profile ranges from one to four, and they are found at depths between 18 and 48 cm. They are mostly flat and continuous, and have an average thickness of 0.71 cm. In Haplustolls with loamy and sandy loam textures, an average 13% increase in lamellae clay content was observed, particularly in the fine colloid fraction (<0.001 mm). In contrast, an average 20% increase in organic matter content was observed in loamy soils. Saturated hydraulic conductivity was significantly reduced (30%-70%) where lamellae were present, altering soil permeability in sandy loam Haplustolls. This study confirms the presence of lamellae in Haplustolls in the central-west region of Córdoba and their effect on decreasing permeability in sandy loam soils. [ABSTRACT FROM AUTHOR]

Self-localization and pose registration are required for sound operation of next generation autonomous vehicles under uncertain environments. Thus, precise localization and mapping are crucial tasks in odometry, planning and other downstream processing. In order to reduce information loss in preprocessing, we propose leveraging LiDAR-based localization and mapping (LOAM) with point cloud-based deep learning instead of convolutional neural network (CNN) based methods that require cylindrical projection. The normal distribution transform (NDT) algorithm is then used to refine the former coarse pose estimation from the deep learning model. The results demonstrate that the proposed method is comparable in performance to recent benchmark studies. We also explore the possibility of using Product Quantization to improve NDT internal neighborhood searching by using high-level features as fingerprints.

Plants respond to their environment through adaptations; for example, earthworms that create heterogeneity can lead to local adaptation of roots. This research identifies a mechanism to explain plant responses to earthworms and how these mechanisms are related. Our results show that tillage intensity has a negative effect on earthworms and root volume. The mean root volume and earthworm biomass under conventional tillage were lower than in reduced tillage and no-tillage. The root volume and the root diameter in the field with residues were higher than in the field without residues, while the root length density and earthworm biomass in the field with residues were lower than in the field without residues. This study demonstrates that the mean of the root length density and biomass of the earthworms were higher in sandy loam than in loam. Therefore, sand content had a positive effect on root length density (R2 = 0.72, p < 0.01) and earthworm biomass (R2 = 0.74, p < 0.01). Earthworm biomass had a positive effect on root volume (R2 = 0.54, p < 0.05) and length density (R2 = 0.88, p < 0.01). This confirms our hypothesis on the effect of earthworms on root systems.

Organic agriculture plays a positive role in promoting genetic diversity, including living organisms, plants, and cultivated crops in the soil. However, few comparative studies reported whether different soil types were suitable for organic cultivation. In this study, loam and clay-loam soils under continuous organic cultivation were analyzed. The results showed that there were no significant differences between two soil types in soil pH, bulk density, total porosity, moisture content and three soil phases. The capillary porosity and organic matter content of loam were significantly higher than those of clay-loam. Compared with clay-loam soil, the contents of total nitrogen, phosphorus, potassium, calcium, zinc and silicon in loam soil were also significantly higher. The microbial diversity was higher in loam and the dominant microbes differed between the two soils. Glycosyl transferases and carbohydrate esterases were enriched in loam, whereas glycoside hydrolases and carbohydrate-binding modules were enriched in clay loam. The potato yield in loam was significantly higher than that in clay loam. Among the tuber quality indicators, the protein content of potatoes in loam was higher than that in clay-loam, but the reducing sugar content was lower for loam than for clay-loam. In conclusion, compared with clay loam, loam was more suitable for organic cultivation of potatoes on account of the high contents of nitrogen, phosphorus, and potassium and the rich microbial community, thus promoting a high yield of tubers. This study provided a theoretical reference for the selection of soil type suitable for organic cultivation. [ABSTRACT FROM AUTHOR]

The object of the study is a laboratory unit for inducing flow to the well using vibration wave draining in carbonate low-permeability reservoirs. Vibratory wave draining is a method used to stimulate flow draining to the well. The method is based on the fact that mechanical waves generated in the soil can cause the opening of microcracks and pores, which leads to an increase in the fluid flow. Vibratory wave scouring can be effectively used to increase fluid flow in low-permeability carbonate reservoirs. Carbonate reservoirs are a common type of reservoir in the oil and gas industry. They often have low permeability, which makes it difficult to extract fluid. With the help of the plunger device developed in the work, a fluid disturbance was created, thereby creating elastic waves in the conventional well (plastic pipe), which were measured using a manual contact vibrometer. This demonstrated the effectiveness of the vibratory method to increase the well productivity and helped to improve the permeability of the rocks, providing better access to challenge the influx of hydrocarbon products. It is shown that with a significant decrease in the permeability of the formation well zone (FWZ), the flow induction should be started only after the restoration works. Otherwise, the well will be significantly hydrodynamically imperfect due to the quality of the reservoir opening, and the flow of production into the well will occur only through a few separate areas of the reservoir with relatively high permeability, which will lead to uneven production of the reservoir and low return of hydrocarbons. Therefore, it is advisable to use the developed method of influencing the productive layer in low-permeability rocks, such as carbonates with layers of clay, siltstones, argillites, and others, with low formation pressures. The obtained results are based on the generation of vibrations that are transmitted to the wellbore. These vibrations can help break up contaminants and fines in carbonate rocks, facilitating the release of hydrocarbon products and improving permeability. [ABSTRACT FROM AUTHOR]

The purpose of this work was to investigate the effect of the burning environment on the properties and phase composition of clinker-based ceramic specimens made from loam with diatomite and bentonite clay in order to develop technological parameters for the manufacture of clinker products. The main raw material used for the experiments was local fusible loam from the Almaty deposit, which is the basis for the production of 75 and 100 grade ceramic bricks. Diatomite from Utesai deposit (Aktobe region) and highly plastic bentonite clay from Darbazin deposit (Turkestan region) were used as additives. Loam and bentonite clay were applied after grinding and sieving through a 1 mm sieve. Diatomite was applied after grinding and milling until it had completely passed through a 0.315 mm sieve. The raw materials are mixed after dosing, and then water is added in the amount required until a pliable mass is obtained. To investigate the properties of the products, standard cylinder samples were prepared with a diameter of 50 mm and a height of 50 mm. The cylinder samples were pressed on a hydraulic press at a pressure of 2–4 kN. The samples were dried in a desiccator at 95–100 °C for 2 h. After drying, the products were burning in a muffle kiln. The analysis of the properties of the burned products showed that the optimum ratio in the ceramic mixture of loam and diatomite to loam and bentonite clay is 85%:15%. After burning in a slightly oxidising environment at 1170 °C, the ceramic specimens correspond to Class 2 for the medium-density and compressive strength grades M 400 and M 500 (GOST 530-2012 (Government standard). X-ray diffractometric analysis showed that the products contain augite, quartz and anorthite as crystalline phases, with the former predominating. After burning in a reducing atmosphere, at 1170 °C, the properties of the samples have higher values compared to the samples burning in a weakly oxidising atmosphere. The resulting properties, according to the regulations, are characteristic of clinker bricks (DIN V 105-1 (technical requirements for clinker façade bricks). After burning in a reducing environment, the phase composition of the products changes qualitatively; in addition to augite and quartz, albite, diopside, orthoclase and haematite are present in the samples.

The relevance of the work is due to the need to expand the raw material base of the construction industry and develop an effective technology for the disposal of waste from water treatment plants. The purpose of the work was to establish the features of the phase composition and structure of loam ceramics and incinerated sewage sludge ash. The work used differential thermal and X-ray phase analysis, electron microscopy. It has been established that the enrichment of loam by the addition of ash from the incineration of domestic sewage sludge (DSS) ensures the connection of aggregates and individual particles into a single system reinforced with anorthite crystals. In this case, an increase in the amount of the anorthite phase and the mechanical strength of ceramics occurs with an increase in the proportion of ash from the incineration of DSS in the charge to more than 20 %. It is shown that the structure of ceramics made from loam with the addition of ash from the combustion of DSS is characterized by a spatial frame, which is a kind of a matrix that combines filler particles according to the "core-shell" type, and an increase in the number of reserve pores, which favorably affects the frost resistance of ceramics.

The purpose of this work was to investigate the effect of the burning environment on the properties and phase composition of clinker-based ceramic specimens made from loam with diatomite and bentonite clay in order to develop technological parameters for the manufacture of clinker products. The main raw material used for the experiments was local fusible loam from the Almaty deposit, which is the basis for the production of 75 and 100 grade ceramic bricks. Diatomite from Utesai deposit (Aktobe region) and highly plastic bentonite clay from Darbazin deposit (Turkestan region) were used as additives. Loam and bentonite clay were applied after grinding and sieving through a 1 mm sieve. Diatomite was applied after grinding and milling until it had completely passed through a 0.315 mm sieve. The raw materials are mixed after dosing, and then water is added in the amount required until a pliable mass is obtained. To investigate the properties of the products, standard cylinder samples were prepared with a diameter of 50 mm and a height of 50 mm. The cylinder samples were pressed on a hydraulic press at a pressure of 2–4 kN. The samples were dried in a desiccator at 95–100 °C for 2 h. After drying, the products were burning in a muffle kiln. The analysis of the properties of the burned products showed that the optimum ratio in the ceramic mixture of loam and diatomite to loam and bentonite clay is 85%:15%. After burning in a slightly oxidising environment at 1170 °C, the ceramic specimens correspond to Class 2 for the medium-density and compressive strength grades M 400 and M 500 (GOST 530-2012 (Government standard). X-ray diffractometric analysis showed that the products contain augite, quartz and anorthite as crystalline phases, with the former predominating. After burning in a reducing atmosphere, at 1170 °C, the properties of the samples have higher values compared to the samples burning in a weakly oxidising atmosphere. The resulting properties, according to the regulations, are characteristic of clinker bricks (DIN V 105-1 (technical requirements for clinker façade bricks). After burning in a reducing environment, the phase composition of the products changes qualitatively; in addition to augite and quartz, albite, diopside, orthoclase and haematite are present in the samples. [ABSTRACT FROM AUTHOR]

Agricultural environment mapping is the premise of the autonomous navigation of agricultural robots. Due to the undulating terrain and chaotic environment, it is challenging to accurately map the environmental maize field using existing LOAM (LiDAR odometry and mapping) methods. This paper proposes a LOAM method based on maize stalk semantic features for 6-DOF (degrees of freedom) pose estimation and field mapping with agricultural robots operating in a dynamic environment. The piecewise plane fitting method filters the ground points for the complex farmland terrain. To eliminate the unstable factors in the environment, we introduce the semantic information of maize plants into the feature extraction. The regional growth method segments the maize stalk instances, the instances are parameterized to a line model, and the optimization method calculates the pose transformation. Finally, the mapping method corrects the drift error of the odometry and outputs the maize field map. This paper compares our method with the GICP and LOAM methods. The trajectory relative errors of our method are 0.88%, 0.96%, and 2.12%, respectively, better than other methods. At the same time, the map drawn by our method has less ghosting and clearer plant edges. The results show that our method is more robust and accurate than other methods due to the introduction of semantic information in the environment. The mapping of corn fields can be further used in precision agriculture. [ABSTRACT FROM AUTHOR]

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This study aimed to identify the composition of ceramic mass for the manufacture of bricks with improved properties based on local loam using diatomite and bentonite clay. For the experiments, loam from the Almaty deposit (Kazakhstan) was applied as the primary product, and used for the production of ceramic bricks with grades of 75 and 100. Diatomite from the Zhalpak and Utesai deposits and highly plastic bentonite clay from the Darbazin deposit (Kazakhstan) were used as additives. An analysis of the properties of the burned products demonstrated that supplementation with diatomite and bentonite in the loam lowers the average density and increases the compressive strength of samples burned at 1000 and 1100 °C. Herewith, the optimal amount of diatomite and bentonite clay to add is 15%, with a fractional composition of 0.315–0.16 mm and less than 1 mm, respectively. It was established that the optimal additions of diatomite and bentonite clay to loam make it possible to obtain after burning at 1170 °C samples of ceramic products corresponding to the 2nd class in terms of the average density and compressive strength grades M 400 and M 500. [ABSTRACT FROM AUTHOR]

Current paper focuses on the laboratory experiments performed wit aim to test the deformation in the frozen loam soil specimens. Loam frozen soils are subject to the external effects, such as climate and environmental impacts including temperature changes. Soil heave is one of the key features restraining possible area development: construction of buildings, roads and railways. Necessarily, this requires the improvements of methods of the assessment of heave. This research evaluated the compressive strength and deformation in several specimens of the frozen soil. The approach included varying load and physical properties of soil specimens: porosity, pore filling, moisture, density of soil particles and dry soil density. Besides during the experiment, the external conditions were changed: decreased temperature and increased load pressure. The experiment is based on the UPG-MG4-01. The paper presented the laboratory tests of heave and compressive strength of the frozen soils using applied geotechnical methods. [ABSTRACT FROM AUTHOR]

Effects of Meloidogyne incognita, Pseudomonas syringae pv. pisi and Rhizobium leguminosarum were studied on growth and biochemical parameters of pea (Pisum sativum L.) in three soil types. Plants grown in 20% fly ash attained higher plant growth, chlorophyll and carotenoid followed by loam soil and 20% sand. Inoculation of R. leguminosarum resulted in increased plant growth, nodulation, chlorophyll and carotenoid over control. Root nodulation and proline contents were high in plants grown in 20% sand and least in 20% fly ash. Inoculation of M. incognita prior to P. syringae pv. pisi resulted in a greater reduction in plant growth, nodulation, chlorophyll and carotenoid content and least where P. syringae pv. pisi was inoculated prior to M. incognita. Inoculation of pathogens increased proline contents. Galling and population of M. incognita was high in 20% sand followed by loam soil and fly ash amended soil. P. syringae pv. pisi and R. leguminosarum had adverse effect on galling and nematode population. The principal component analysis identifies interaction of pathogens and showed segregation of various treatments in the plots. [ABSTRACT FROM AUTHOR]

Experimental research of weak bases reinforced by vertical soil-cement elements are discribed in this article. Tray research of weak clay bases and bases with percent of reinforcement from 2,1% to 7,1% under strip stamp were conduct. As a result of the experiment settlements for each of soil base models were obtained. Characteristic curves of the influence of the reinforcement percentage on the bearing capacity, deformability are given, character of settlements of the investigated soil mass in time at step-increasing loading are shown. It was found that depending on the percentage of reinforcement the critical pressures increased linearly and the values of settlement at critical pressures were determined increased with the base reinforcement percentage. Empirical dependencies were obtained to determine the critical pressures depending on the percentage of reinforcement for the investigated soil conditions. In conclusion, the effectiveness of reinforcing the base of the strip foundations by vertical soil-cement elements was proved.

Agricultural environment mapping is the premise of the autonomous navigation of agricultural robots. Due to the undulating terrain and chaotic environment, it is challenging to accurately map the environmental maize field using existing LOAM (LiDAR odometry and mapping) methods. This paper proposes a LOAM method based on maize stalk semantic features for 6-DOF (degrees of freedom) pose estimation and field mapping with agricultural robots operating in a dynamic environment. The piecewise plane fitting method filters the ground points for the complex farmland terrain. To eliminate the unstable factors in the environment, we introduce the semantic information of maize plants into the feature extraction. The regional growth method segments the maize stalk instances, the instances are parameterized to a line model, and the optimization method calculates the pose transformation. Finally, the mapping method corrects the drift error of the odometry and outputs the maize field map. This paper compares our method with the GICP and LOAM methods. The trajectory relative errors of our method are 0.88%, 0.96%, and 2.12%, respectively, better than other methods. At the same time, the map drawn by our method has less ghosting and clearer plant edges. The results show that our method is more robust and accurate than other methods due to the introduction of semantic information in the environment. The mapping of corn fields can be further used in precision agriculture.

Disease complex of carrot (Daucus carota L.) involving root knot nematode Meloidogyne incognita and two fungi Alternaria dauci and Rhizoctonia solani were studied in three soil types. More plant growth, chlorophyll, carotenoid and proline contents were found in carrot grown in fly ash mix soil than plants grown in sand mix soil and loamy soil. Inoculation of M. incognita, R. solani, and A. dauci reduced plant growth, chlorophyll and carotenoid but increased proline contents. Inoculation of M. incognita 20 days prior to a fungal pathogen caused a greater reduction in plant growth, chlorophyll and carotenoid than fungal pathogen was inoculated prior. Inoculation of A. dauci prior to R. solani or vice versa had a similar effect on plant growth, chlorophyll, and carotenoid. Nematode multiplication and galling was higher in plants grown in sand mix soil followed by loamy soil and fly ash mix soil. Both fungi had adverse effects on galling and nematode multiplication. Blight disease index caused by A. dauci was 3 and crown rot index by R. solani was also recorded 3. These disease indices were 5 when pathogens were inoculated in combinations.

A comparative agronomical experiment was conducted at research station/ Department of Horticulture and Landscape/ College of Agriculture/ Tikrit University, to study the effect of two different soil textures (loam and silt loam) on growth and yield of six varieties of okra. The two soil textures were analyzed for pH, nitrogen, organic matter, phosphorous, Ca, K, Mg etc. at the Central Laboratory of Soil Science and Water Resource Department, College of Agriculture, Tikrit University. Six okra varieties of okra were used in this experiment (i. e., Clamson, Hussainawia, Sultani, Btra, Clemson and Clemson spinless). The experiment was carried out with a Randomized Complete Block Design with Split plot arrangement with four replicates. Data were recorded for plant height, stem diameter, branches number on main stem, total number of branches, pod length, pod diameter, pod weight, pods number, yield per plant and percentage of dry matter in pod. Results indicated that plant height, branches number on main stem, pod weight, pod number and yield per plant produced in Loam soil were significantly higher (P ≤ 0.05) than those produced in Silt loam soil. Irrespective of soil texture, the stem diameter, branches number on main stem and total branches produced in Btra variety, whereas, pod diameter, pod weight, pod number and pod yield per plant produced in Hussainawia variety were significantly higher (P ≤ 0.05) than those produced in other varieties. But, pod length did not differ significantly (P ≤ 0.05) between six varieties. It can be concluded from the present findings that Btra and Hussainawia cultivars may be produced in different soil..

This study aimed to identify the composition of ceramic mass for the manufacture of bricks with improved properties based on local loam using diatomite and bentonite clay. For the experiments, loam from the Almaty deposit (Kazakhstan) was applied as the primary product, and used for the production of ceramic bricks with grades of 75 and 100. Diatomite from the Zhalpak and Utesai deposits and highly plastic bentonite clay from the Darbazin deposit (Kazakhstan) were used as additives. An analysis of the properties of the burned products demonstrated that supplementation with diatomite and bentonite in the loam lowers the average density and increases the compressive strength of samples burned at 1000 and 1100 °C. Herewith, the optimal amount of diatomite and bentonite clay to add is 15%, with a fractional composition of 0.315–0.16 mm and less than 1 mm, respectively. It was established that the optimal additions of diatomite and bentonite clay to loam make it possible to obtain after burning at 1170 °C samples of ceramic products corresponding to the 2nd class in terms of the average density and compressive strength grades M 400 and M 500.

Domestication of biennial Lepidium campestre L. offers possibilities for more varied crop rotations in cold regions, with increased crop cover during winter. In the first winter after sowing, L. campestre can reduce nitrogen (N) leaching before harvesting in the second year. In this system no soil tillage is needed during the first year, unlike in systems with annual crops. A three-year leaching study on loam soil in southern Sweden revealed significantly (p

Walls of wet loam, used in earthen houses, generally experience more shrinkage which results in cracks and less compressive strength. This paper presents a technique of producing loam masonry blocks that are compacted in drained state during casting process in order to minimize shrinkage. For this purpose, loam masonry blocks were cast and compacted at a pressure of 6 MPa and then dried in shade by covering them in plastic sheet. The results show that linear shrinkage of 2% occurred which is smaller when compared to un-compacted wet loam walls. This implies that the loam masonry blocks compacted in drained state is expected to perform better than un-compacted wet loam walls.

The problem of developing a new generalized strength (plasticity)condition is applied to soils of anisotropic, in particular a transversal - isotropic (trans - structural) structure. This condition is derived by generalizing the known Coulomb - Moore plasticity condition σc for two directions: along the layers parallel and crosswise to layers, that is, for the perpendicular directions to the layers, relative to the isotropy plane for the transtropic soil, systematized for the first time by A.K. Bugrov and A.I. Golubev. It is proposed to analyze the possibility of generalizing the conditions of plasticity (strength) in the principal stresses σ1 and σ2, as well as on the values of the critical principal stress σ1c and σ2c, proposed and developed in due time for soils of the isotropic structure N.A. Tsytovich and N.S. Bulychev. Following the approach of W. Witke, who proposed to apply such a criterion to rocks of an orthotropic structure, the formulated criterion is proposed, which allows to determine the moment of the onset of plastic destruction of anisotropic soil and the direction of its further spread from the initial point. The table contains critical values of anisotropic soil in two orthogonal directions of the coordinate axes, calculated with the help of the proposed new criterion, which allows us to solve a new class of problems of fracture mechanics.

The effect of nanosized additives on the strength properties of ceramics based on fusible brick loam of the Klyuchischenskoye deposit has been studied. In general, all nanosized additives selected for the study had a positive effect on the strength properties of ceramics. The greatest increase in strength, when using nanosized silica ash Laksil 30, was 70 %, in relation to the control sample. When using silica ash, an increase in the content of the amorphous phase in the shard after firing is noted against the background of a decrease in its porosity, which causes an increase in strength characteristics. The nature of the destruction of the samples also differed. The destruction of the control sample was accompanied by the formation and gradual opening of cracks. The destruction of the modified samples was more fragile in comparison with the control. Thus, the effectiveness of nanosized additives on the strength properties of ceramics is shown.