Distribution of different forms of phosphorus in calcareous soils from middle and south of Iraq

Author(s):  
Makttoof E.A. ◽  
Kassim J.K. ◽  
Khuzale K.H

A survey of the chemical way to determine the amount of different phosphorus forms in calcareous soils was carried out on 22 calcareous soils fertilized for many years with phosphate fertilizers from central and southern Iraq. Extraction methods were developed by combining the technique of individual traditional methods of different forms with sequentially extraction technology. Soil samples were collected from surface (0-30 cm) and subsurface (30-60 cm) horizons. Forms of soluble, ready available, organic and total phosphorus were extracted independently and in addition to the successive extraction were carried out according to Jiang and Gu (1989) method. The amount of soluble and available phosphorus extracted were low and ranged from 0.17 to 2.12 mg kg-1 and 7.28 and 34.3 mg kg-1 respectively. Organic phosphorus was medium and the values ranged 30.9 and 93.1 mg kg-1 while the total phosphorus content was high and the values ranged between 206.9 and 570.6 mg kg-1. The quantities of phosphorus extracted sequentially by chemical extracts and the possibility of diagnosing different forms of phosphorus associated with calcium Ca2-P, Ca8-P and Ca10-P (apatite) in addition to P associated with OM and free iron and aluminum oxides. The average values of Ca2-P, Ca8-P, Fe-P and occluded (O-P) extracted were nearly similar and the values were 20.47, 25.28, 25.4, and 26.23 mg kg-1 respectively while the Ca10-P was much higher (194.54 mg kg-1) than the other forms.

1959 ◽  
Vol 31 (1) ◽  
pp. 120-130
Author(s):  
Armi Kaila

The effect on a fen soil of superphosphate applied for 34 years at the annual rates of 0, 100, 200, and 300 kg/ha was studied. The material consisted of samples from a field trial at the Leteensuo Experiment Station. The soil samples from the ploughing layer were collected in autumn 1956, and the hay samples from the crop harvested in 1957. The hay yields from the treatments with 200 or 300 kg/ha of superphosphate were about 7400 kg/ha, and the phosphorus content of the hay 1.69 and 1.85 per cent, respectively. The treatment with 100 kg/ha of superphosphate yielded only about 5100 kg/ha of hay dry matter with a very low phosphorus content, 0.96 per cent. The yield from the untreated plots was almost negligible. Also the biological and chemical soil tests showed that the untreated soil was almost depleted of available phosphorus. The phosphorus conditions in the soil annually treated with 100 kg/ha of superphosphate were not significantly better than in the untreated soil. An annual anplication of 200kg/ha of superphosphate was able to maintain a more satisfactory rate of available phosphorus in the soil, but only the treatment with 300 kg/ha of superphosphate resulted in markedly higher test values than those for the lower treatments. The total phosphorus content of the soil was the higher the larger the amount of superphosphate applied. About 40 to 50 per cent of the differences between the total phosphorus content of the treated and untreated samples was due to organic phosphorus. The potassium content of the hay was the lower the higher the superphosphate treatment. The hay from the treatment with 300 kg/ha of superphosphate contained only 1.25 per cent potassium. The possibility that potassium was a minimum factor in this treatment was discussed.


2020 ◽  
Vol 150 ◽  
pp. 03011
Author(s):  
Husam Al-Nussairi ◽  
Khalida Hassan

In this study, the marshlands in southern Iraq were investigated, focusing on the Hawizeh Marshlands and adjacent areas, by studying the scenario and quantities of water, in addition to the hydraulic and hydrochemical characteristics. To accomplish the objects of this study the researcher visited some fields, made interview with farmers, specialists, authorities and directorates related to this study. The results of this study indicate that there are a huge problem existed in the drainage systems with absence of natural outlets, the discharges of drainage water is towards Al- Hawizeh marsh which flow back its water into Tigris river through several canals, increasing salinity, scare of water, miss-use of land, lack of governments efforts to promote agricultural production leads to loss of soil productivity and land degradation.


2011 ◽  
Vol 138-139 ◽  
pp. 933-936 ◽  
Author(s):  
Xuan Chen ◽  
Hong Yu Luo ◽  
Jun Yu ◽  
Peng Xiang Yue ◽  
Lin Zhou ◽  
...  

Alcohol-alkali method and base digestion method were investigated to extract proteins from tea residues, respectively. According to single factorial experiments, results showed that the optimal extraction technology of alcohol-alkali method were pH 12, temperature of 80 °C, ethanol concentration of 60%, liquid-solid ratio of 40, 60 min, and the protein extraction rate reached 15.0%. And the optimal extract conditions of base digestion were pH 12, temperature of 80 °C, liquid-solid ratio of 50, 80 min, which made the protein yield reached 31.5%. Furthermore, alcohol-alkali method was more beneficial to protein extraction from tea residues under lower temperature and weak alkali condition (40-60 °C, pH 8-10). While base digestion had higher extraction yield under high temperature and strong alkali condition (60-80 °C, pH 11-12).


2021 ◽  
pp. 3570-3586
Author(s):  
Mohanad M. Al-Ghuribawi ◽  
Rasha F. Faisal

     The Yamama Formation includes important carbonates reservoir that belongs to the Lower Cretaceous sequence in Southern Iraq. This study covers two oil fields (Sindbad and Siba) that are distributed Southeastern Basrah Governorate, South of Iraq. Yamama reservoir units were determined based on the study of cores, well logs, and petrographic examination of thin sections that required a detailed integration of geological data and petrophysical properties. These parameters were integrated in order to divide the Yamama Formation into six reservoir units (YA0, YA1, YA2, YB1, YB2 and YC), located between five cap rock units. The best facies association and petrophysical properties were found in the shoal environment, where the most common porosity types were the primary (interparticle) and secondary (moldic and vugs) . The main diagenetic process that occurred in YA0, YA2, and YB1 is cementation, which led to the filling of pore spaces by cement and subsequently decreased the reservoir quality (porosity and permeability). Based on the results of the final digital  computer interpretation and processing (CPI) performed by using the Techlog software, the units YA1 and YB2 have the best reservoir properties. The unit YB2 is characterized by a good effective porosity average, low water saturation, good permeability, and large thickness that distinguish it from other reservoir units.


2016 ◽  
Vol 16 (4) ◽  
pp. 1149-1158 ◽  
Author(s):  
Gang Wen ◽  
Qin Deng ◽  
Ting-Lin Huang ◽  
Jun Ma

Microbially available phosphorus (MAP) is the labile phosphorus that is readily assimilated by microorganisms, which is linearly correlated to bacterial re-growth in drinking water in some regions. The conventional MAP bioassay for drinking water was originally developed by Markku based on the growth potential of Pseudomonas fluorescens P17 (P17). However, the bioassay bears some demerits, such as time-consuming and labor-intensive enumeration. For convenience, an alternative method based on a similar principle was developed to assess the content of MAP in drinking water, in which natural microbial consortium was used as inoculum instead of pure culture P17, cell number was counted using flow cytometry (FCM), and cultivation at 30 °C was adopted. Natural microbial consortium is able to efficiently utilize organic phosphorus and exhibit high sensitivity since more cells are produced per μg P utilized. FCM is a rapid method to count all bacteria growing in drinking water. With incubation temperature increasing up to 30 °C, there is a shorter test period (64 h), excellent sensitivity and better utilization efficiency for organic phosphorus. The results show that the developed bioassay is sensitive, time-saving and easily operated.


2014 ◽  
Vol 68 (7) ◽  
Author(s):  
Wioleta Pietrzak ◽  
Renata Nowak ◽  
Marta Olech

AbstractThe total content of polyphenols and flavonoids determined in the same plant and their corresponding antioxidant activities may vary widely, depending on the extraction conditions applied. This study was conducted to optimise the extraction conditions of phenolics and flavonoids from the mistletoe plant. Various extraction methods, i.e. ultrasound-assisted extraction technology, maceration, maceration with stirring, accelerated solvent extraction (ASE), and extraction under reflux were evaluated for their percentage extraction of polyphenols (TPC) and flavonoids (TFC) from Viscum album subsp. abietis. In addition, the anti-radical activity of extracts was analysed using the 2,2-diphenyl-1-picrylhydrazyl method. The effects of temperature, solvent type, and concentration on the phenolic extraction efficiency and antioxidant activity were studied using chemometric and statistical methods. The results showed that the extracts of V. album subsp. abietis contained large amounts of polyphenols and flavonoids (up to 57.673 mg g−1 and 9.955 mg g−1 of dry extract, respectively) and exhibited potent antioxidant activity, hence representing promising sources of powerful antioxidants. Due to its high extraction efficiency and considerable saving of time and solvent, ASE was more effective than the other extraction techniques. Extracts prepared with water-polar solvent mixtures displayed the highest TPC, TFC, and antioxidant activity, while organic polar solvents were the least efficient extractants.


1969 ◽  
Vol 52 (3) ◽  
pp. 587-592
Author(s):  
Paul R Caudill

Abstract The alkalimetric variation of the quimociac method was shown by collaborative testing to be accurate and precise for determining total phosphorus, citrate-insoluble phosphorus, or available phosphorus by the direct method. The method is recommended for adoption as official first action.


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