irrigation period
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2021 ◽  
Vol 20 (4) ◽  
pp. 134-140
Author(s):  
Sooyoung Kim ◽  
Eun-Jin Kwon ◽  
Hyunjin Jo ◽  
Seong-Hae Jeong

Objectives: During caloric irritation, the spinning/rotating sensation is predominant. However, there is no report on the temporal relationship between caloric nystagmus and perception.Methods: Consecutive 57 participants underwent bithermal caloric test in the dizziness clinic of Chungnam National University Hospital from February 2018 to September 2018. For vestibular perception, we asked the subject to report feelings of rotation and/or linear sensation during each warm and cold water irrigation period. Besides routine caloric parameters, the duration of nystagmus and vestibular sensation were analyzed.Results: In most participants, the caloric nystagmus preceded the vestibular sensation (79.6% in right warm, 83.3% in left warm, 88.5% in right cool, and 84.6% in left cool stimuli). The precedence of perception was observed in 5 normal persons and 15 patients with vestibular migraine (n=4), unilateral vestibulopathy (n=3), and Menière’s disease (n=2), multiple systemic atrophy (n=2), cerebellar ataxia (n=2), vertebrobasilar insufficiency (n=1), and post-earthquake dizziness (n=1). The mean latency between nystagmus and perception was 11.7 seconds. And the duration of nystagmus was longer than that of perception in all conditions. Non-spinning sensations during the caloric test were also observed in some participants (26.8% in right warm, 30.3% in left warm, 29.1% in right cool, and 24.1% in left cool stimuli).Conclusions: During the bithemal alternate caloric test, various vestibular perception and temporal relationship between perception and nystagmus suggest the bithermal caloric stimulation does not reflect only the signal originating from the horizontal canal pathway. A further validation study is needed.


2021 ◽  
Vol 939 (1) ◽  
pp. 012089
Author(s):  
A Rau ◽  
I Begmatov ◽  
G Rau

Abstract Studies on Akdala rice system found that rice plants sensitive to meteorological conditions. Climate change leads to changes in crop structure. The temperature of the rice field air and water has a special influence on the structure of the rice crop. It is established that the temperature of the water layer in rice paddies in the irrigation period does not exceeds 290 C, which is below the threshold of 350 C, when the flow and discharge of water from the paddies are recommended. The temperature of water in rice paddies, the surface layer was determined by an express thermometer, at the depth of the water layer 5, 10, 15 and 20 cm by Savin Thermometers, soil – thermometers TM-5.


2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Yuansheng Zhang ◽  
Zhiwei Cao ◽  
Wei Wang ◽  
Xin Jin

AbstractJoint operation of the Longyangxia and Liujiaxia reservoirs (Long-Liu operation) is of great significance for water and sediment regulation in the Yellow River. The water–sediment–electricity coupling system is a giant system with complex nonlinear relationships. A reliable Long-Liu operation scheme facilitates maximization of the benefits of the water–sediment–electricity system. Based on systems thinking, this paper quantitatively evaluated the reliability of different Long-Liu operation schemes and coordination of the water–sediment–electricity coupling system through the entropy weight method and dissipative structure model. The results indicated that the current operation scheme is more reliable than the adjusted scheme at the inter-annual scale and during the summer-autumn flood season and ice flood season within a year. However, the operation scheme should be improved during the spring irrigation period. The key factors influencing the quality of the water–sediment–electricity system include the outflow of the Liujiaxia reservoir, incoming sediment load into the Yellow River at Toudaoguai, sediment inflow-outflow difference in the Ningxia-Inner Mongolia Reach, water flow at Lanzhou and power generation upstream of Toudaoguai. The water–sediment–electricity system under the current Long-Liu operation scheme is more coordinated than that in the adjusted state, but the overall coordinated development of the system remains at a low activity level.


2021 ◽  
Author(s):  
Zihe Wang ◽  
Jing Jin ◽  
Wei Liu ◽  
Tenglin Deng ◽  
Yiping Zhao ◽  
...  

Abstract The Yellow River irrigation area in Tumochuan Plain is one of the primary grain production areas in the middle and upper reaches of the Yellow River Basin (YRB). The groundwater in the area is bitter and salty, which significantly influences drinking water safety of residents. To investigate its chemical characteristics and material sources, we collected 12 groundwater samplings, 3 irrigation water samplings, and 1 precipitation sample during the winter irrigation period (WIP) in November 2016 and the spring irrigation period (SIP) in April 2017, respectively. We then analysed the hydrogen and oxygen stable isotopes and hydrochemical characteristics of the shallow groundwater in the study area and investigated their affecting factors by using environmental isotopes, Gibbs diagrams, Schoeller diagrams, and ion proportionality coefficient analysis. Next, we qualitatively analysed the material sources. The results show the followings: (1) The concentrations of major ions in groundwater in the SIP are generally higher than in the WIP, which may be recharged by snow melting water in the spring. (2) The average values of δD and δ18O for the groundwater are -78.0‰ and -10.3‰, respectively, in the WIP and -77.4‰ and -10.3‰, respectively, in the SIP. However, the characteristics of hydrogen and oxygen isotopes in the groundwater are almost identical in the WIP and SIP. (3) The formation of groundwater chemical constituent are controlled by evaporation concentration and lixiviation, and dissolution of evaporite and mirabilite is the most important factor. Synchronously, the formation of groundwater chemical constituent is also influenced ion exchange and human activities. The study provides effective guidance for groundwater resource development in arid and semi-arid regions.


Water ◽  
2021 ◽  
Vol 13 (10) ◽  
pp. 1383
Author(s):  
Eunjeong Lee ◽  
Taegeun Kim

The water quality of the Dongjin River deteriorates during the irrigation period because the supply of river maintenance water to the main river is cut off by the mass intake of agricultural weirs located in the midstream regions. A physics-based model and a data-driven model were used to predict the water quality in the Dongjin River under various hydrological conditions. The Hydrological Simulation Program–Fortran (HSPF), which is a physics-based model, was constructed to simulate the biological oxygen demand (BOD) in the Dongjin River Basin. A Gamma Test was used to derive the optimal combinations of the observed variables, including external water inflow, water intake, rainfall, and flow rate, for irrigation and non-irrigation periods. A data-driven adaptive neuro-fuzzy inference system (ANFIS) model was then built using these results. The ANFIS model built in this study was capable of predicting the BOD from the observed hydrological data in the irrigation and non-irrigation periods, without running the physics-based model. The predicted results have high confidence levels when compared with the observed data. Thus, the proposed method can be used for the reliable and rapid prediction of water quality using only monitoring data as input.


2021 ◽  
Vol 16 (2) ◽  
pp. 185-189
Author(s):  
Ali Hassan Hommadi ◽  
Wisam Abdulabbas Abidalla ◽  
Ahmed Sami Naser

One use of technology in agriculture involves setting up a reserving sheet for subsurface moisture under the root zone of wheat crops, which is symbolized by SWRT, to conserve the water in the root zone. This reduces the field water losses by raising the efficiency of water use (WUE) and economical water productivity (EWP). For this study, an SWRT membrane sheet was put under the root zone of wheat crops throughout the growing season, from the winter of November 2019 to the end of the season in April 2020, in a free field. The study was conducted on a private farm located in the province of Babylon in Sadat Al-Hindya Town, which is approximately 70 km from the capital (Baghdad). Surface irrigation was utilized for the irrigation of the wheat crops. Two methods were used: method A1 utilized the SWRT sheet and method A2 was conducted without the SWRT sheet. The irrigation water supply, irrigation period, and soil water content before and after irrigation were computed and recorded every day for the A1 and A2 methods. The values of wheat crop production (yield), water use efficiency, and economical water productivity from the two plots were computed and compared. The results obtained for water use efficiency for the two methods, A1 and A2, were 0.51 and 0.47 kg/m3, respectively. The increment in yield of plot A1 compared with plot A2 was 6.45%. The increment in WUE of plot A1 compared with plot A2 was 8.55%. In addition, the WP of the wheat crop for plots A1 and A2 were 144.44 and 119.16 ID/m3, respectively, while the increment in WP of plot A1 compared with plot A2 was 21.21%. The findings show that the SWRT method prevents the environmental effects of pesticide and fertilizers that enter the groundwater and pollute it. This technology assists in saving water and plant nutrients, and prevents pollution of the groundwater from pesticides and excess fertiliser.


2021 ◽  
Author(s):  
Tinashe Mawodza ◽  
Manoj Menon ◽  
Masoud Babaei ◽  
Genoveva Burca ◽  
Oxana V. Magdysyuk

<p>Soil salinisation is one of the most potent forms of land degradation that affects soils of arid and semi-arid regions of the world. Management of soils with potential for salinisation is key to ensuring the sustainability of marginal soils in predominantly dry regions of the world. In this research, to assess the potential impact of irrigation with saline water on the physical properties of a marginal soil. We subjected a sandy loam soil to flood irrigation with water of variable salinity levels (namely 0, 2,  5 and 10 g/L NaCl) for up to 40 days. After every irrigation cycle, each of the soil samples was subjected hydraulic conductivity measurements for the duration of the experiment. At the end of the 40 day experimental irrigation period, soil cores were non-invasively scanned using X-Ray CT scanning to assess for changes in pore distribution as a result of the different irrigation quality water. Furthermore, measurement of other physio-chemical soil properties such as aggregate stability, EC and pH of each soil were also done to get a more complete idea of the changes that occurred during the experiment. </p>


2021 ◽  
Vol 264 ◽  
pp. 01015
Author(s):  
Zulfiya Mirkhasilova ◽  
Мurat Yakubov ◽  
Lyudmila Irmuhamedova

In recent years, there has been a shortage of water resources in the basins of the Amu Darya and Syrdarya rivers, which is the result of the development of new lands for irrigation and the inappropriate use of water and land resources. A side effect of irrigation and land reclamation is the increasing flow of collector-drainage waters every year, which leads to a deterioration in the land reclamation state and pollution of water resources, which can lead to the ecological disaster of land and water resources. Currently, in the Republic of Uzbekistan, from the total volume of water resources of the Amu Darya and Syrdarya rivers, up to 68% is used for irrigation. Of this volume on the Republic territory, about 12% of collector-drainage waters of deteriorated quality are formed. With a shortage of water resources, they are used for irrigation. But irrigation with saline waters can lead to a deterioration in the land reclamation state. In this regard, new irrigation technologies are proposed, which can save both irrigation water and it is advisable to use underground pumped water for irrigation. Field experiments were carried out in the farm "Khozhilkhon-hozhi" in the farm named after A. Niyazov, Kuva district, Fergana region. A feature of the soil conditions in this farm is the small thickness of the covered fine earth, underlain by highly permeable gravel, strong and increased water permeability, with a deep groundwater level (GWL> 3 m). Large water losses are observed during irrigation. The calculation task was to determine how many hectares of land can be irrigated from one vertical drainage well, taking into account the irrigation time, inter-irrigation period, etc. The water-salt balance of the reclaimed lands for 2017-2019 was compiled. The water-salt balance showed that water supply and filtration from canals and atmospheric precipitation play the main role in the inlet part. In the consumable part, the main place is occupied by evapotranspiration and drainage flow. In general, a negative balance is formed on the territory annually by the type of a small salt carryover within 2.85 t / ha. On the territory of the farm and the experimental plot, cotton of the S-6524 variety was sown, the flow rate of the well is 30 l / s, the furrow consumption is 0.5 l / s. The composition of hypothetical salts in the pumped-out waters is calculated After the first irrigation of our field, the pumped-out water is diverted to the neighboring fields, while the first inter-irrigation period is 20 days. In the interval of these 20 days until the second irrigation of the cotton of the original field, it is possible to irrigate the same fields 5 hectares 8 times, in total 40 hectares of land. The experiments showed that irrigation with pumped water from vertical drainage wells did not have a negative impact on the yield of cotton. And the use of the recommended irrigation technology will reduce the shortage of irrigation water and improve the ecological situation of water resources.


Author(s):  
T. I. Drovovozova ◽  
◽  
A. A. Kirilenko ◽  

Purpose: analysis of problematic issues associated with the hydrochemistry of natural waters and the processes occurring in the irrigation systems of Rostov region. Discussion. The specificity of growing crops associated with irrigated agriculture has led to the formation of significant volumes of drainage and waste water (58676.5 thousand cub. m at the level of 2019). The quality of drainage wastewaters is determined by the hydrochemistry of groundwater and water intakes and has a seasonal character. In drainage systems operation of the Central irrigated zone, an unregulated inflow of salt-forming ions into water inlets was noted, and their concentration in the places where drainage wastes are discharged into small water bodies of the Lower Don (for example, Kostylevsky pr., Kolodezki ur., Solenaya river, erik Besheny) differs little from the background geochemical concentrations and corresponds to the natural saline background of the studied objects. Since irrigation and drainage systems are the objects of negative impact on the environment, uncontrolled natural processes of salt-forming ions migration in adjacent environments in combination with desalinization processes during the irrigation period led to violations of ecological legislation by the land reclamation and agricultural water supply departments in terms of exceeding the standards of maximum permissible concentrations for water bodies for fishery purposes, approved by the Order of the Ministry of Agriculture of 13.12.2016 no. 552. Conclusions. Regularities in formation of salt-forming ions migration processes in adjacent media have been revealed. It has been determined that one of the sources and agents of “saline contamination” of drainage and natural waters is groundwater. Hydrochemical materials and analysis of regulatory legal acts in terms of water bodies protection and use indicate the need to establish standards admitted to chemical substances concentrations disposal, taking into account the regional natural (nominally natural) hydrochemical background and natural and climatic characteristics differentiated for each small water body.


Author(s):  
A. S. Shtanko ◽  
◽  
V. N. Shkura ◽  

Purpose: technical support for drip irrigation of the inter-row root-inhabited soil space in fruit garden plantations. Materials and methods. The object of the study was the irrigation network of perennial tree-fruit orchard plantations. During the research, analysis and variant comparison were carried out, highlighting the advantages and disadvantages of the structures under consideration. When improving the design of the drip irrigation facility, the methods of exploratory design were used. Results. During the research, the experience of operating the drip irrigation systems of perennial orchards was generalized and the basic requirements for the drip irrigation network in perennial orchards were formed. As an object for further research, partially satisfying these requirements, a constructive diagram of a drip irrigation facility for moistening the soil in the inter-row root-inhabited soil space of tree-fruit orchard plantations, given in RU Patent no. 2713136, was adopted. The disadvantage of this design of a drip irrigation facility is low reliability of the elastic coupling, which should be deformed when the position of the drip console changes, have the necessary rigidity to lift the drip console from the working position to the idle position, and be a sealed conduit connecting the drip console and the tee. As a result of the research, an improved design of the irrigation structure has been proposed, which does not include deformable elements. Conclusions. The proposed design scheme of a drip irrigation facility for perennial fruit plantations meets the requirements of manufacturability, has the ability to automatically operate in the irrigation mode and in the inter-irrigation period, and provides irrigation water supply to certain points of the location of the developed root system of perennial plants, including the inter-row root-inhabited soil space.


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