THE SPATIAL DIFFERENTIATION OF SOIL SALINITY AT THE YOUNG SALINE COASTAL PLAIN OF THE CASPIAN REGION

The study is focused on the pattern of soil salinity at the young loamy coastal plains of the Caspian Sea in Russia and Iran which were released from water less than 300 years ago. At two key sites of 45×30 m (Russia) and 25×20 m (Iran), the soil sampling with 1 to 5 m grid was performed to the depth of 1 m. The electrical conductivity (1 : 2.5) was measured in soil samples and soil sa-linity maps were compiled. Soils are represented by solonchaks with 2–3% of salts in the top layer or highly saline soils partly leached in the upper 5–10 cm. The ground water table is shallow (2–2.5 m). The studied sites are different in terms of climate, microtopography, and vegetation cover but spatial differentiation of soil salinity is quite similar what is evidenced from the similar distributions (mean values and variance) of electrical conductivity in almost all studied depths. The redistribution of salts is mainly observed in the upper 50 cm with the maximal manifestation in the upper 5 cm.

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METODOLOGIA PARA AVALIAÇÃO DA SALINIDADE DO SOLO EM AMBIENTE PROTEGIDO

Irriga ◽

10.15809/irriga.2009v14n3p383-397 ◽

2009 ◽

Vol 14 (3) ◽

pp. 383-397 ◽

Cited By ~ 6

Author(s):

Sergio Oliveira Pinto de Queiroz ◽

Roberto Testezlaf ◽

Edson Eiji Matsura

Keyword(s):

Electrical Conductivity ◽

Electric Conductivity ◽

Soil Salinity ◽

Vacuum Solution ◽

Irrigation Management ◽

Saline Soils ◽

Soil Electrical Conductivity ◽

Saturation Extract ◽

Productive Process ◽

Salinity Levels

METODOLOGIA PARA AVALIAÇÃO DA SALINIDADE DO SOLO EM AMBIENTE PROTEGIDO Sérgio Oliveira Pinto de Queiroz1; Roberto Testezlaf2; Edson Eiji Matsura21Departamento de Tecnologia e Ciências Sociais, Universidade do Estado da Bahia, Juazeiro, BA, [email protected]. 2Faculdade de Engenharia Agrícola, Universidade Estadual de Campinas, Campinas, SP 1 RESUMO Em condições de ambiente protegido a irrigação é essencial e a fertirrigação um agente facilitador do manejo da água e fertilização do solo; todavia, o uso contínuo e nem sempre adequado pode elevar a salinidade do solo, comprometendo o processo produtivo. Este trabalho objetivou avaliar uma metodologia para caracterizar a ocorrência de salinização em cultivos protegidos, usando diferentes métodos para determinação da condutividade elétrica do solo. Em laboratório foram avaliados os equipamentos Sensor Sigma Probe EC1, da Delta-T e extratores de solução do solo à vácuo. Os equipamentos foram utilizados em três solos com diferentes texturas e sob cinco níveis de salinidade: 0, 2, 4, 8 e 12 dS. m-1 a 25° C. Os resultados obtidos pelos métodos avaliados foram comparados ao método do extrato de saturação. O equipamento Sigma Probe EC1, por apresentar melhor correlação com o método de referência na fase laboratorial, foi utilizado nas visitas as propriedades, sob produção em ambiente protegido, na macrorregião de Campinas, revelou ser mais eficiente. A aplicação do questionário associada às leituras de condutividade elétrica do solo com o sensor Sigma Probe permitiu diagnosticar a deficiência no manejo da água e condutividade elétrica nas propriedades avaliadas. Os valores obtidos de condutividade elétrica no extrato de saturação do solo para as propriedades visitadas, não caracterizam solos salinos, mas podem afetar a produção de flores e outras plantas sensíveis à salinidade. UNITERMOS: manejo da irrigação; fertirrigação. QUEIROZ, S. O. P. de.; TESTEZLAF, R.; MATSURA, E. E. METHODOLOGY FOR SOIL SALINITY EVALUATION IN GREENHOUSE 2 ABSTRACT Under controlled environmental conditions, irrigation is essential and the use of fertigation becomes a facilitator agent for water and fertilization management. However, the intensive use of fertigation in this type of productive process can increase soil salinity, and affect productive process. This work objective was to evaluate a methodology in order to characterize the salinization process occurrence of in greenhouse farms using different methods to determine soil electric conductivity l. Sigma Probe EC1, manufactured by Delta-T and vacuum solution manufactured extractors were evaluated under laboratory conditions. The equipment was used in three different soil textures, under five salinity levels: 0, 2, 4, 8 and 12 dS. m-1 at 25° C. The obtained results of electric conductivity were compared to the saturation extract method. The Sigma Probe EC1 equipment was used in farm visits, with controlled environmental production inCampinas macro region. Among the used equipment in the laboratorial part, the sigma Probe EC1 presented the best results for soil electrical conductivity determination, when compared to saturation extract, in saline and non saline soils. Using the questionnaire for electric conductivity determinations using Sigma Probe sensor it was possible to verify the deficiency in the soil moisture and electrical conductivity management. The obtained results for electric conductivity using the saturation extract methods do not characterize saline soils on the visited farms, but they showed that the salinity levels in the soil could affect flower production and other crops sensitive to salinity. KEYWORDS: irrigation management, fertigation.

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Growth and Mineral Nutrition in Salt Stressed Guava ( Psidium guajava L.) cv . Allahabad Safeda

Journal of AgriSearch ◽

10.21921/jas.v3i1.11403 ◽

2016 ◽

Vol 3 (1) ◽

Author(s):

ANSHUMAN SINGH ◽

ASHWANI KUMAR ◽

R.K. YADAV ◽

ASHIM DUTTA ◽

D.K. SHARMA

Keyword(s):

Electrical Conductivity ◽

Chemical Composition ◽

Plant Height ◽

Salinity Tolerance ◽

Soil Ph ◽

High Salinity ◽

Psidium Guajava ◽

Sodium Adsorption Ratio ◽

Saline Soils ◽

Experimental Soil

Guav a cv . Allahabad Safeda w as grown in saline soils and irrigated with the best av ailable w ater -1 -1 + -1 (EC 2.8 dS m ). Based on chemical composition (pH- 7.1, EC - 2.8 dS m , Na - 20.04 meq l and IW IW sodium adsorption ratio- 4.86), irrigation w ater w as categorized as marginally saline. The soil pH 2 -1 w as mostly below 8.5 but mean electrical conductivity (EC ) v alues ranged from 0.5-2 dS m 2 indicating moderate to high salinity in the experimental soil. After one-y ear of experimentation, fiv e plants randomly selected from each treatment and the data w ere recorded. Plant height -1 -1 significantly increased (LSD 5%) with increase in salinity from 0.5 dS m to 1.4 dS m . A similar -1 trend w as noted with respect to stem girth. The av erage plant height at 0.5, 0.9 and 1.4 dS m salinity lev els w as 98.3 cm, 108.3 cm and 123 cm, respectiv ely whereas the corresponding stem girth v alues -1 w ere 2.24 cm, 2.28 cm and 2.46 cm. At 2 dS m salinity ,how ev er , both av erage plant height (94.6 cm) and stem girth (2.24 cm) significantly decreased and w ere found to be comparable to control (0.5 dS -1 + -1 m ) v alues. Plants show ed negligible Na accumulation in leav es up to 1.4 dS m salinity , but -1 + exposure to elev ated salinity (2 dS m ) significantly increased leaf Na (0.16% DW). These data -1 indicated a salinity tolerance (EC )threshold of about 1.5 dS m inguav a cultiv ar Allahabad Safeda.

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Estimation of bulk permittivity of the Moon’s surface using Lunar Radar Sounder on-board Selenological and Engineering Explorer

Earth Planets and Space ◽

10.1186/s40623-020-01259-2 ◽

2020 ◽

Vol 72 (1) ◽

Author(s):

Keigo Hongo ◽

Hiroaki Toh ◽

Atsushi Kumamoto

Keyword(s):

Electrical Conductivity ◽

Physical Properties ◽

Titanium Content ◽

Spectroscopic Observation ◽

Lunar Rock ◽

Almost All ◽

Mare Serenitatis ◽

Radar Sounder ◽

Lunar Maria ◽

Regolith Layer

Abstract Site-dependent bulk permittivities of the lunar uppermost media with thicknesses of tens to hundreds meters were estimated based on the data from Lunar Radar Sounder onboard the Selenological and Engineering Explorer (SELENE). It succeeded in sounding almost all over the Moon’s surface in a frequency range around 5 MHz to detect subsurface reflectors beneath several lunar maria. However, it is necessary to estimate the permittivity of the surface regolith of the Moon in order to determine the actual depths to those reflectors instead of apparent depths assuming a speed of light in the vacuum. In this study, we determined site-dependent bulk permittivities by two-layer models consisting of a surface regolith layer over a half-space with uniform, but different physical properties from the layer above. Those models consider the electrical conductivity as well as the permittivity, whose trade-off was resolved by utilizing the correlation between iron–titanium content and measured physical properties of lunar rock samples. Distribution of the iron–titanium content on the Moon’s surface had already been derived by spectroscopic observation from SELENE as well. Four lunar maria, Mare Serenitatis, Oceanus Procellarum, Mare Imbrium, and Mare Crisium, were selected as regions of evident reflectors, where we estimated the following four physical properties of each layer, i.e., bulk permittivity, porosity, loss tangent and electrical conductivity to conclude the actual depths of the reflectors are approximately 200 m on average. The bulk permittivity ranges from 2.96 at Mare Imbrium to 6.37 at Oceanus Procellarum, whereas the porosity takes the values between 1.8 and 41.1% in the respective maria. It was found that although the bulk permittivity of the four lunar maria differs from a mare to a mare, it shows a good correlation with their composition, viz., their iron–titanium content.

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Assessment of soil salinity indexes using electrical conductivity sensors

Scientia Horticulturae ◽

10.1016/j.scienta.2021.110171 ◽

2021 ◽

Vol 285 ◽

pp. 110171

Author(s):

Sebastián Bañón ◽

Sara Álvarez ◽

Daniel Bañón ◽

María Fernanda Ortuño ◽

María Jesús Sánchez-Blanco

Keyword(s):

Electrical Conductivity ◽

Soil Salinity

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Spatial and Temporal Variability of Soil Salinity in the Yangtze River Estuary Using Electromagnetic Induction

Remote Sensing ◽

10.3390/rs13101875 ◽

2021 ◽

Vol 13 (10) ◽

pp. 1875

Author(s):

Wenping Xie ◽

Jingsong Yang ◽

Rongjiang Yao ◽

Xiangping Wang

Keyword(s):

Electrical Conductivity ◽

Spatial Distribution ◽

Soil Salinity ◽

Yangtze River ◽

Laboratory Data ◽

River Estuary ◽

Yangtze River Estuary ◽

Soil Electrical Conductivity ◽

The Yangtze River ◽

The Yangtze River Estuary

Soil salt-water dynamics in the Yangtze River Estuary (YRE) is complex and soil salinity is an obstacle to regional agricultural production and the ecological environment in the YRE. Runoff into the sea is reduced during the impoundment period as the result of the water-storing process of the Three Gorges Reservoir (TGR) in the upper reaches of the Yangtze River, which causes serious seawater intrusion. Soil salinity is a problem due to shallow and saline groundwater under serious seawater intrusion in the YRE. In this research, we focused on the temporal variation and spatial distribution characteristics of soil salinity in the YRE using geostatistics combined with proximally sensed information obtained by an electromagnetic induction (EM) survey method in typical years under the impoundment of the TGR. The EM survey with proximal sensing method was applied to perform soil salinity survey in field in the Yangtze River Estuary, allowing quick determination and quantitative assessment of spatial and temporal variation of soil salinity from 2006 to 2017. We developed regional soil salinity survey and mapping by coupling limited laboratory data with proximal sensed data obtained from EM. We interpreted the soil electrical conductivity by constructing a linear model between the apparent electrical conductivity data measured by an EM 38 device and the soil electrical conductivity (EC) of soil samples measured in laboratory. Then, soil electrical conductivity was converted to soil salt content (soil salinity g kg−1) through established linear regression model based on the laboratory data of soil salinity and soil EC. Semivariograms of regional soil salinity in the survey years were fitted and ordinary kriging interpolation was applied in interpolation and mapping of regional soil salinity. The cross-validation results showed that the prediction results were acceptable. The soil salinity distribution under different survey years was presented and the area of salt affected soil was calculated using geostatistics method. The results of spatial distribution of soil salinity showed that soil salinity near the riverbanks and coastlines was higher than that of inland. The spatial distribution of groundwater depth and salinity revealed that shallow groundwater and high groundwater salinity influenced the spatial distribution characteristics of soil salinity. Under long-term impoundment of the Three Gorges Reservoir, the variation of soil salinity in different hydrological years was analyzed. Results showed that the area affected by soil salinity gradually increased in different hydrological year types under the impoundment of the TGR.

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Survey of Phenolic Acids, Flavonoids and In Vitro Antioxidant Potency Between Fig Peels and Pulps: Chemical and Chemometric Approach

Molecules ◽

10.3390/molecules26092574 ◽

2021 ◽

Vol 26 (9) ◽

pp. 2574

Author(s):

Lahcen Hssaini ◽

Francisca Hernandez ◽

Manuel Viuda-Martos ◽

Jamal Charafi ◽

Rachid Razouk ◽

...

Keyword(s):

Phenolic Acids ◽

Radical Scavenging ◽

Fruit Peel ◽

Mean Values ◽

Local Cultivar ◽

Ic50 Values ◽

The Mean ◽

Lipid Peroxidation Inhibition ◽

Almost All

In the present study, chromatic coordinates, phenolic acids, flavonoids and antioxidant capacity assessed by 1,1-diphenyl-2-picrylhydrazyl (DPPH), 2,2′-azino-bis (3-ethylbenzothiazoline-6-sulfonate (ABTS) and lipid peroxidation inhibition capacity (LPIC) essays and their relative IC50 were investigated in 25 fig cultivars growing in Morocco. The aims of this study were to determine (i) the variation in these compounds among light and dark-colored cultivars, (ii) their partitioning between fruit peel and pulp and (iii) to display network connections among these variables. Twelve phenolic compounds (PCs) were isolated in peel extract versus eight in pulp samples. Anthocyanins, mainly cyanidin-3,5-diglucoside and cyanidin-3-O-rutinoside, were the predominant compounds in peels, where the mean concentrations were 75.90 ± 18.76 and 77.97 ± 18.95 µg/g dw, respectively. On the other hand, (−)-epicatechin and cyanidin-3-O-rutinoside were the major compounds in the pulp extracts, where the mean values were 5.23 ± 4.03 and 9.01 ± 5.67 µg/g dw, respectively. A two-dimensional hierarchically clustered heatmap was applied to the dataset to explore correlations in the dataset and similarities between cultivars, without dimensionality reduction. Results showed that anthocyanins, particularly pelargonidin-3-O-rutinoside, cyanidin-3,5-diglucoside and cyanidin-3-O-rutinoside, were the main contributors to the peels’ free radical scavenging capacity. This capacity was particularly higher in the peel of dark-colored figs compared to the fruit pulp. The local cultivar “INRA 1301” showed the most promising phenolic profile due to its very high levels of almost all detected PCs, especially (−)-epicatechin, quercetin-3-O-rutinoside, quercetin-3-O-glucoside, cyanidine-3,5-diglucoside, cyanidine-3-O-rutinoside and pelargonidin-3-O-rutinoside (54.66, 141.08, 35.48, 494.08, 478.66, 12.56 µg/g dw, respectively). Having the darkest figs in the collection (L* = 25.72, c* = 22.09 and h° = 20.99), this cultivar has also combined promising IC50 values, which were of 19.85, 40.58 and 124.78 µg/mL for DPPH, ABTS and LPIC essays, respectively.

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Studies on Polyaniline: Polyethyleneterephthalate Films

Solid State Phenomena ◽

10.4028/www.scientific.net/ssp.111.99 ◽

2006 ◽

Vol 111 ◽

pp. 99-102 ◽

Cited By ~ 2

Author(s):

A.A. Ahmed ◽

Faiz Mohammad

Keyword(s):

Electrical Conductivity ◽

Electrical Properties ◽

Arrhenius Equation ◽

Great Increase ◽

Thermooxidative Stability ◽

Ambient Conditions ◽

Dc Electrical Conductivity ◽

The Stability ◽

Almost All ◽

Conductivity Retention

The films of polyaniline:polyethyleneterephthalate films were prepared by polymerizing aniline soaked in polyethyleneterephthalate films of different thicknesses. The films were characterized by FTIR as well as for their electrical properties. The electrical properties of the films were observed to be of good quality as almost all the films showed a great increase in their electrical conductivity from insulator to semiconductor region after doping with hydrochloric acid. All the films in their doped state follow the Arrhenius equation for the temperature dependence of electrical conductivity from 35 to 115oC. The thermooxidative stability was studied by thermogravimetry and differential thermal analysis. The stability in terms of dc electrical conductivity retention was also studied under ambient conditions by two slightly different techniques viz. isothermal and cyclic techniques. The dc electrical conductivity of the films was found to be stable below 90oC for all the films under ambient conditions.

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The Soviet-Iranian Treaty of 1921: History and Modernity (to the Centenary of Conclusion)

Восток Афро-Азиатские общества история и современность ◽

10.31857/s086919080017726-5 ◽

2021 ◽

pp. 191

Author(s):

Zaven A. Arabadzhyan

Keyword(s):

Caspian Sea ◽

Legal Status ◽

The Caspian Sea ◽

National Interests ◽

Economic Relations ◽

Bilateral Relations ◽

Property Transfer ◽

Soviet Russia ◽

Set Up ◽

Almost All

After a century since the Soviet-Iranian Treaty was signed in 1921 authors of the article consider its significance from a new viewpoint – as the backing of the sovereignty of Iran and Russia that supported development of their relations. Authors examine the way it complied with the interests of Russia and Iran, and its impact on the bilateral relations in the 20th century. The signing of the Treaty secured the sovereignty of Iran, served as the base for the development of equal relations between the two neighboring states and opened up Iran for relations with foreign states. For the Russia, this document was a step towards breaking its diplomatic isolation. The authors emphasize that Russia had granted almost all its property to Iran which contributed to the improvement of the financial situation in Iran and served as a base for the development of mutually beneficial economic relations between the two countries. The authors mention that the property transfer clause was connected with the security of the Soviet Russia. This fact was reflected in the Article 6 of the Treaty. The Treaty set up the basement for the legal status of the Caspian Sea as a closed sea in the states' joint usage. The Convention on the Legal Status of the Caspian Sea, signed in 2018, to some extent retained the special regime of the sea and reflected the spirit of the Treaty of 1921. Although in IRI there are different views about the Treaty some experts consider that it generally complied with Iran's national interests.

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Analysis of the Dielectric Constant of Saline-Alkali Soils and the Effect on Radar Backscattering Coefficient: A Case Study of Soda Alkaline Saline Soils in Western Jilin Province Using RADARSAT-2 Data

The Scientific World JOURNAL ◽

10.1155/2014/563015 ◽

2014 ◽

Vol 2014 ◽

pp. 1-14 ◽

Cited By ~ 10

Author(s):

Yang-yang Li ◽

Kai Zhao ◽

Jian-hua Ren ◽

Yan-ling Ding ◽

Li-li Wu

Keyword(s):

Dielectric Constant ◽

Soil Salinity ◽

Frequency Effect ◽

Complex Dielectric Constant ◽

Saline Soils ◽

Suitable Model ◽

Backscattering Coefficient ◽

Mixed Pixel ◽

Western Jilin Province

Soil salinity is a global problem, especially in developing countries, which affects the environment and productivity of agriculture areas. Salt has a significant effect on the complex dielectric constant of wet soil. However, there is no suitable model to describe the variation in the backscattering coefficient due to changes in soil salinity content. The purpose of this paper is to use backscattering models to understand behaviors of the backscattering coefficient in saline soils based on the analysis of its dielectric constant. The effects of moisture and salinity on the dielectric constant by combined Dobson mixing model and seawater dielectric constant model are analyzed, and the backscattering coefficient is then simulated using the AIEM. Simultaneously, laboratory measurements were performed on ground samples. The frequency effect of the laboratory results was not the same as the simulated results. The frequency dependence of the ionic conductivity of an electrolyte solution is influenced by the ion’s components. Finally, the simulated backscattering coefficients measured from the dielectric constant with the AIEM were analyzed using the extracted backscattering coefficient from the RADARSAT-2 image. The results show that RADARSAT-2 is potentially able to measure soil salinity; however, the mixed pixel problem needs to be more thoroughly considered.

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X. Growing Tension and the Threat of War in the Southern Caspian Sea: The Unsettled Division Dispute and Regional Rivalry

Perspectives on Global Development and Technology ◽

10.1163/156915003322986406 ◽

2003 ◽

Vol 2 (3) ◽

pp. 575-591

Author(s):

Hooman Peimani

Keyword(s):

Caspian Sea ◽

The United States ◽

Caspian Region ◽

Legal Regime ◽

The Caspian Sea ◽

Military Conflict ◽

American Military ◽

Military Presence ◽

Military Conflicts ◽

Southern Caspian Sea

AbstractThe absence of an acceptable legal regime for the division of the Caspian Sea among its five littoral states has created grounds for conflicts, crises, and wars in the Caspian region, a situation worsened since 2001 when Iran, Azerbaijan, and Turkmenistan found each other on a collision course over the ownership of certain offshore oilfields. The region has since been heading towards militarization, while the persistence of conflicts over the Caspian Sea's division has prepared the ground for military conflicts. Fear of lagging behind in an arms and the manipulation of conflicts by the United States and Turkey have further encouraged militarization. Against this background, certain factors, including Turkey's efforts to deny Iran political and economic gains in the Caspian region, the growing American military presence in Eurasia, and the expanding American-Azeri military ties since 11 September 2001 will likely contribute to the creation of a suitable ground for a military conflict in the Caspian region.

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