scholarly journals PHYSIO-CHEMICAL PROPERTIES OF TIDAL FLATS SEDIMENTS IN IRAQI COASTLINE, NORTHWEST OF ARABIAN GULF

2020 ◽  
Vol 53 (2E) ◽  
pp. 107-116
Author(s):  
Dounia Al-khuzaie

The quantitative and qualitative physic-chemical properties considered in more than 15 geographical sites were selected along the Iraqi coastline. The grain size analysis and the EC, pH, TDS, K, Na, Mg, Ca, HCO3, Cl, SO4 were estimated in the sediments sample. Three types of soil textures dominate which are sandy clay, sandy clay loam and clay loam were observed in the present study. The results show that the pH value ranges from7.67-8.19, EC (23-68.45 dS/m), TDS (14720-43808 ppm), Na (6388-20746 ppm), K (73.225-211.875ppm), Ca (306.25-537.5 ppm), Mg (675-2475ppm), Cl (6160-18350 ppm), SO4 (1680-4080 ppm), HCO3 (93.75-225 ppm), SAR (37.61-107.95). The analytical results for the surface samples presented the impact of both solodization and salinization processes. They are shown from the high values of EC and domination of Na in the exchangeable complex. The ions occur in the following concentration order: Na > Mg > Ca > K and Cl > SO4 > HCO3.

Author(s):  
Rajendra Hegde ◽  
M. B. Mahendra Kumar ◽  
K. V. Niranjana ◽  
K. V. Seema ◽  
B. A. Dhanorkar

By using digitized cadastral map and satellite imagery an investigation was carried out to study the vertical distribution of physical and chemical properties of soils of Ramapura-1 microwatershed of Yadgirtaluk and district of Karnataka, India. The soil texture varied from loamy sand to sandy clay loam in surface and sandy clay loam to clay in subsurface. The per cent moisture distribution was varied from 3.89 to 54.94 per cent and it was increase with depth. The soils under the study were slightly acidic to alkaline (5.57 to 10.32) and non-saline in reaction. The organic carbon content was low to high (0.12 to 1.16 %) and decreased with depth. The per cent calcium carbonates in soils ranged from 0.60 to 8.19 per cent and uneven distribution in most of the soil series. The distribution of exchangeable bases in the order of Ca2+>Na+>Mg2+>K+. Most of the soil series were irregular in distribution of CEC (1.70 to 51.20 cmol (p+) kg-1) and CEC/clay ratio. The per cent base saturation was increase with depth in most of the series.


2020 ◽  
Vol 8 (6) ◽  
pp. 1038-1041
Author(s):  
C Bharathi ◽  
P Murali Arthanari ◽  
C Chinnusamy

Soil Research ◽  
2019 ◽  
Vol 57 (8) ◽  
pp. 814 ◽  
Author(s):  
Arkadiusz Telesiński ◽  
Teresa Krzyśko-Łupicka ◽  
Krystyna Cybulska ◽  
Barbara Pawłowska ◽  
Robert Biczak ◽  
...  

This study used laboratory experiments to compare the effects of coal tar creosote on the activity of oxidoreductive enzymes in sandy loam, loamy sand and sandy clay loam soils. Different amounts of coal tar creosote were added to soil samples as follows: 0 (control), 2, 10 or 50 g kg–1 dry matter. The activity of soil dehydrogenases (DHAs), o-diphenol oxidase (o-DPO), catalase (CAT), nitrate reductase (NR) and peroxidases (POX) was determined. Contamination of soil with coal tar creosote affected oxidoreductase activity. Oxidoreductive enzyme activity following soil contamination with coal tar creosote was in the following order: DHAs > CAT > NR > POX > o-DPO in loamy sand and in sandy loam; and DHAs > POX > CAT > NR > o-DPO in sandy clay loam. The index of soil oxidoreductive activity (IOx) introduced in this study confirms the negative effect of coal tar creosote on oxidoreductase activity in soil. DHAs were the most sensitive to the contamination of soil with coal tar creosote. Moreover, the greatest changes in oxidoreductase activities were observed in loamy sand. Knowledge of the mechanism underlying the effects of coal tar creosote on oxidoreductive processes may enable development of a method for the bioremediation of polycyclic aromatic hydrocarbon-contaminated soils.


2021 ◽  
Vol 14 (4) ◽  
Author(s):  
Haroon Shahzad ◽  
Muhammad Iqbal ◽  
Noman Latif ◽  
Muhammad Arshad Khan ◽  
Qudrat Ullah Khan

2021 ◽  
Author(s):  
Michele Delchiaro ◽  
Giulia Iacobucci ◽  
Francesco Troiani ◽  
Marta Della Seta ◽  
Paolo Ballato ◽  
...  

<p>The Seymareh landslide is the largest rock slope failure (44 Gm<sup>3</sup>) ever recorded on the exposed Earth surface. It detached ∼10 ka BP from the northeastern flank of the Kabir-Kuh anticline (Zagros Mts., Iran) originating the natural dam responsible for the formation of a three-lake system (Seymareh, Jaidar, and Balmak lakes, with an area of 259, 46, and 5 km<sup>2</sup>, respectively). The lake system persisted for ∼3000 yr during the Holocene before its emptying phase due to overflow. A sedimentation rate of 21 mm yr<sup>−1</sup> was estimated for the Seymareh lacustrine deposits, which increased during the early stage of lake emptying because of enhanced sediment yield from the lake tributaries. </p><p>To reconstruct the climatic and environmental impact on the lake infilling, we reviewed the geomorphology of the basins and combined the results with multi-proxy records from a 30 m thick lacustrine sequence in Seymareh Lake. Major analyses comprise grain size analysis, carbon and oxygen stable isotopes of carbonate-bearing sediments, and X-ray diffraction analysis of clay minerals.</p><p>Lake overflowing is largely accepted as the main response to variations in water discharge and sediment supply since the alternation from dry to wet phases enhances sediment mobilization along hillslopes decreasing the accommodation space in the downstream sedimentary basins. In this regard, during the early-middle Holocene, the Seymareh area, as well as the entire Middle East, was affected by short-term climate changes at the millennial-scale, as testified by both paleoecological and archaeological evidence. Indeed, several records from Iranian lakes (i.e., Mirabad, Zeribar, Urmia) well documented the temperature and the moisture conditions of the western Zagros Mountains during the Holocene. During the early Holocene, the precipitation remained low up to 6 ka BP, reaching the driest condition around 8-8.2 ka BP. The impact of this abrupt climate change is evident across West Asia, where the first large villages with domesticated cereals and sheeps disappeared, converting to small hamlets and starting habitat-tracking. As regards the Seymareh area, a more irregular distribution of rainfalls and their increasing seasonality may support rhexistasy conditions, during which the scarce vegetation cover enhances both the hillslope erosion and sedimentation rate in the basins, most likely contributing to the overflow of Seymareh Lake. </p>


1970 ◽  
Vol 21 (1) ◽  
pp. 41-49
Author(s):  
O Adegbuyi ◽  
GP Ojo ◽  
AJ Adeola ◽  
MT Alebiosu

The physical and chemical properties of clay deposits around Isua-Akoko, Akure, Lafe and Ayadi in Ondo State southwestern Nigeria have been examined. The results have shown that Isua-Akoko, Akure and Lafe Clays are plastic fire clays while Ayadi clay is kaolinite. Grain size analysis reveals that Isua Akoko Clay contains 45% of clay, 18% silt, 12% fine sand,14% medium sand and 11% coarse sand and no gravel; Akure clay contains 42% clay, 14% silt, 13% fine sand, 20% medium sand and 8% coarse sand with 1% gravel. Lafe Clay contains 21% clay, 8% silt, 25% fine sand, 37% medium sand and 8% coarse sand with 1% gravel while Ayadi clay contains 83% clay and 17% silt. The liquid limits of these clay samples range from 41% to 73%% and plastic limits range from 18% to 26% respectively. The chemical analysis reveals that the most abundant mineral is silica (60.97%) and aluminum was next in abundance (23.69%) while other oxides are low. The results show that Isua-Akoko and Akure are residual while Lafe and Ayadi are sedimentary and transported Clays. The firing test, PH, and bleaching tests of the clays are also discussed. The chemical and physical characteristics of the clay deposits are strongly indicative of their industrial importance in the production of ceramics, refractories, paving bricks, paint and pharmaceutical products.KEYWORDS: Kaolinite, fire clay, gravel, ceramics and alumina.


2017 ◽  
Vol 9 (2) ◽  
pp. 720-729
Author(s):  
Sanjay T. Satpute ◽  
Man Singh

The understanding of soil and nutrient dynamics under drip fertigation is relevant for crop production as well as water and nutrient management. The aim of this study was to generate information about the distribution of phosphorus (P) under different fertigation strategies for onion production on sandy clay loam soil during 2007-2008 to 2008-2009. The study involved field experiment, laboratory analysis and modeling of P distribution. The phosphorus distribution data in the field were collected, analyzed and used to calibrate and validate the solute transport model HYDRUS-2D for sandy clay loam soil. The performance of HYDRUS-2D was evaluated by comparing its simulated values with the observed values of soil moisture and nutrient concentration. The coefficient of determination (R2), root mean square error (RMSE) and mean absolute error (MAE) were used as model performance indicators. The range of R2 between 0.72-0.99 for water as well as nutrient distribution indicates good correlation between the observed and simulated values. The MAE and RMSE values for water and nutrient distribution were in between 0.0009 to 0.0039 which indicated the accuracy of the model. From these results, it can be concluded that the model is performing well for predicting the P concentration in the soil as well as the soil moisture distribution for onion crop grown under sandy clay loam. The model was also validated for water and phosphorus distribution with the observed values at the end of the crop season and found to be performing well. The HYDRUS-2D model may be used to carry out simulations for different soil types and with different fertigation and irrigation strategies for developing guidelines.


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