Experimental study on the correlation between the partial and total salt content in saline gravel using ion chromatography

2021 ◽  
Vol 26 ◽  
pp. 100424
Author(s):  
Liyang Wang ◽  
Jiankun Liu ◽  
Xinbao Yu ◽  
Xu Li ◽  
Anand J. Puppala ◽  
...  
1981 ◽  
Vol 46 (2) ◽  
pp. 368-376 ◽  
Author(s):  
Josef Veselý

Titration of sulphates with lead perchlorate employing lead ion selective electrode indication was studied using additions of various organic solvents at different pH' and ionic strength values. As the optimum emerged systems with 60-70% 1,4-dioxane, pH' 5.3-5.6. After dehydration with sodium hydroxide, dioxane must be freed from the electrode surface-oxidizing impurities by their reduction with sodium metal and subsequent distillation. The method was applied to determination of sulphates in mountain spring waters. Units of ppm can be determined; the limit of determination, however, depends considerably on the content of dioxane, total salt content in the sample, and speed of the semi-automatic titration. Lead can be determined with EDTA in concentrations down to c(Pb2+) = 5 . 10-6 mol l-1.


Agronomy ◽  
2021 ◽  
Vol 11 (8) ◽  
pp. 1535
Author(s):  
Tonggang Fu ◽  
Hui Gao ◽  
Jintong Liu

Numerous methods have been used in the spatial prediction of soil salinity. However, the most suitable method is still unknown in arid irrigation regions. In this paper, 78 locations were sampled in salt-affected land caused by irrigation in an arid area in northern China. The geostatistical characteristics of the soil pH, Sodium Adsorption Ratio (SAR), Total Salt Content (TSC), and Soil Organic Matter (SOM) of the surface (0–20 cm) and subsurface (20–40 cm) layers were analyzed. The abilities of the Inverse Distance Weighting (IDW), Ordinary Kriging (OK), and CoKriging (CK) interpolation methods were compared, and the Root Mean Square Error (RMSE) was used to justify the results of the methods. The results showed that the spatial distributions of the soil properties obtained using the different interpolation methods were similar. However, the surface layer exhibits more spatial heterogeneity than the subsurface layer. Based on the RSME, the nugget/sill value and range significantly affected which method was the most suitable. Lower nugget/sill values and lower ranges can be fitted using the IDW method, but higher nugget/sill values and higher ranges can be fitted using the OK method. These results provide a valuable reference for the prediction of soil salinity.


2011 ◽  
Vol 91 (5) ◽  
pp. 889-902 ◽  
Author(s):  
J. J. Miller ◽  
J. A. Brierley

Miller, J. J. and Brierley, J. A. 2011. Solonetzic soils of Canada: Genesis, distribution, and classification. Can. J. Soil Sci. 91: 889–902. Soils of the Solonetzic order are defined as having a Solonetzic B horizon designated as a Bn or Bnt horizon. The Solonetzic Order includes four great groups: Solonetz, Solodized Solonetz, Solod, and Vertic Solonetz. Solonetzic soils are thought to develop via the stepwise pedogenic processes of salinization, solonization (desalinzation and alkalization), and solodization. Soluble salts are brought into the soil pedon of Solonetzic soils by capillary movement and evaporation from spring to fall, and upward water flow from the water table to the freezing zone in the winter deposits salts upon freezing. Solonization proceeds when desalinization lowers the total salt content and alkalization is initiated by high exchangeable Na. Solodization occurs when anisotropic flow conditions or a change in vertical hydraulic gradients prevent capillary rise and replenishment of soluble Na in the Bn horizon. Two common Solonetzic catenas are found in the prairies. In the first sequence, Gleyed Solonetz or Solonetz occur in the depressional areas of the landscape, and soils then grade through Solodized Solonetz, Solods, and in some cases, Chernozems or normal zonal soils at higher elevations. In the second sequence, Solods are found in the lowest topographic position, while Solodized Solonetz, Solonetz and Chernozems are found at progressively higher slope positions. Solonetzic soils have unique properties that adversely affect their use for agriculture and other land uses (e.g., construction, septic systems). Further interdisciplinary research is required to better understand the genesis of these soils at the “meter scale” or local landscape level because of the extreme spatial variability of these soils.


2020 ◽  
Vol 5 (4(73)) ◽  
pp. 12-18
Author(s):  
G.T. Bekmirzaev ◽  
I.A. Begmatov ◽  
D.B. Yulchiev

The purpose of the experimental study was the selection of salt tolerant crops and the search for useful horticultural species for growing them on saline lands. The experimental study was conducted at the University of Algarve, Portugal, in a greenhouse. The following vegetable crops were selected for research: lettuce (Lactuca sativaL), New Zealand spinach (Tetragonia tetragonioides) and garden purslane (Portulaca oleracea). Experimental results showed that New Zealand spinach and garden purslane have high potential as species resistant to high salt content and are therefore recommended for cultivation in order to reduce soil salinity. The above crops, mainly New Zealandspinach, are good types of garden crops with high useful qualities and productivity. Therefore, it has been shown that this method is a clean and environmentally friendly tool to prevent salinization and maintain the sustainability of agricultural systems


2019 ◽  
Vol 27 (6) ◽  
pp. 638-657 ◽  
Author(s):  
V. Yu. Chevychelov

The results of experimental studies of the behavior of volatile components (Cl, F, CO2 and H2O) in fluid-magmatic systems are presented. The maximum chlorine content in magmatic melts mainly depends on the composition of the melt and, to a lesser extent, on pressure (10300 MPa) and temperature (8001000C). The Cl content in the melt increases from 0.20.3 to 35 wt.% with increasing in the Ca content during the transition from polymerized granitoid to depolymerized basaltic melts. The pressure dependence of solubility has a maximum at a pressure of about 100200 MPa. A tendency of increasing in the Cl content and decreasing in the F content in the melt during the transition from acidic and alkaline to basaltic melts has been established. The maximum Cl content in the melt significantly increases from rhyolitic (up to 0.25 wt.%) to phonolitic (up to 0.85 wt.%) and dacitic (up to 1.2 wt.%) at temperatures of 10001200C and pressure of 200 MPa. The addition of CO2 to the system causes an increase in the Cl content in the melt by 2025 relative %, which is apparently associated with an increase in the Cl activity in the fluid. In this case, the H2O content in the melt decreases by ~ 0.51.0 wt.%. A strong effect of hydrolysis was shown in the interaction of an alumina-rich granitic melt with ~ 0.51N chloride fluid. This effect shows that at hypabyssal magmatic conditions (P = 100 MPa, T = 750C), the fluid is acidic (the pH after the experiment is ~ 11.5) and it is characterized by high dissolving power. It was established experimentally that as a result of the interaction of aqueous Na-K-Ca-chloride fluid of variable composition with granodioritic and granitic melts in the pressure range of ~ 100200 MPa and temperatures of 8201000C and with increasing in the total salt content, the Na and K replace Ca in the silicate melt, displacing the latter into the fluid, that is enriched in CaCl2 and is depleted in NaCl. Experimental results on the joint partitioning of Cl and F provide a quantitative basis for understanding the degassing processes in the course of the evolution of alkaline and basaltic magmas. They are important for assessing the extent of the removal of Cl and F into the earths atmosphere during volcanic activity and the effects of this removal on climate change.


1994 ◽  
Vol 287 (1-2) ◽  
pp. 65-73 ◽  
Author(s):  
Shouzhuo Yao ◽  
Kang Chen ◽  
Fangnan Zhu ◽  
Dazhong Shen ◽  
Lihua Nie

1941 ◽  
Vol 60 (1) ◽  
pp. 107-139 ◽  
Author(s):  
Alec Milne

In the seaward direction in an estuary there are usually the following main gradients:—(a) Increase in osmotic pressure (total salt content, especially chlorides).(b) Increase in calcium and magnesium content.(c) Increase in alkalinity.(d) Increase in winter and decrease in summer temperature.(e) Increase in light penetration.There are other gradients of less importance. The first three are dependent on salinity. Thus, from the ecological standpoint, the three important physical observations relative to the study of estuarine life are the salinity, temperature, and light (silt content) gradients.Ecological studies are directed towards the elucidation of two types of problems:(i) Characteristics of the physical environment relevant to the distribution of specific forms of life.(ii) The growth of mixed populations and their interrelations in a homogeneous environment or in a physical gradient.The present study concerns itself especially with the former, and to a less extent with the latter.


1952 ◽  
Vol 30 (6) ◽  
pp. 410-450 ◽  
Author(s):  
J. E. Moore

Forty-nine species of Entomostraca were found in 48 lakes situated in the southern half of Saskatchewan. These lakes form a series ranging from fresh to extremely saline waters. The salinity in most cases was less than 10,000 p.p.m. The occurrence of Entomostraca is correlated with the degree of salinity. Total concentration is considered to be of prime importance in determining presence or absence of species. There were pronounced differences in the total salt content of waters inhabited by the various species. Cladocera were more markedly restricted by high salinity than were Copepoda. Littoral species were apparently more susceptible to increasing concentration than were those of limnetic habits. Typical entomostracan communities in these lakes are discussed. The communities in highly saline waters are quite comparable to those reported in similar habitats in other parts of the world. Marked alterations in the fauna of two lakes have resulted from salinity changes over a period of 20 years. Tentative upper limits of salinity tolerance for many of the species have been proposed. Salt concentrations of between 4000 and 16,000 p.p.m. appear to be upper limits for most freshwater types. The majority of species are considered to possess no special osmoregulatory mechanisms. Except for Artemia salina and Moina hutchinsoni the Entomostraca present in these lakes are typically freshwater species which in general have a wide geographic distribution. The fauna has undoubtedly been derived from many sources and in only a few instances are there indications of definite points of origin.


Water ◽  
2019 ◽  
Vol 11 (12) ◽  
pp. 2456 ◽  
Author(s):  
Kaiming Li ◽  
Hongguang Liu ◽  
Xinlin He ◽  
Xinxin Li

With the popularization and development of drip irrigation under film, the problem of secondary soil salinization in Xinjiang is becoming more and more serious. To explore water and salt transport in drip irrigation under mulch and drainpipe drainage, drainage tests of drainage ditches in saline-alkali soil in the Xinjiang 112 group were used to monitor soil salinity changes by controlling field irrigation. Then, a HYDRUS (PC-Progress, Prague, Czech Republic) numerical model was used to simulate and analyze the changes in salinity during cotton growth and the autumn salt return stage in saline-alkali soil under drainage conditions. The agreement between the simulated and measured values was high, and the model parameters were reliable. During the growth period of cotton, the salinity continued to decrease, and the salt began to return after the harvest. Compared with before planting, in the 0–80 cm soil layer, the average desalinization rate reached 43.52% under the mulching films, and the average desalinization rate reached 13.83% under and between the mulching films. After the cotton was harvested, salt returned to the upper layer of soil. However, it still showed a decrease compared with the level before sowing. The average salt content of 0–80 cm soil decreased by 5.14%, and the average salt content of 0–200 cm decreased by 2.60%. This shows that the total salt content in soil will continue to decrease after long-term use of drip irrigation and underground pipe drainage.


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