IRAQI JOURNAL OF DESERT STUDIES

Cesium-137 has been worldwide used for estimation soil erosion. Its movement and transport in the environmental media depend on its retention by soil. Retention capacity of soil for radionuclides and pollutants as expressed by the distribution coefficient Kd (ratio of radionuclides retained by soil to those remained in liquid) that was estimated for 137Cs in some soils of Iraq. The soils were varied in clay 24.0-50.5%, organic mater 0.5-1.5%, and lime content 28.1-35.0%. Results showed that all the factors investigated were found to alter the values of Kd. The mean of Kd was 774 L kg-1 in the loam soil increased to 4375 L kg-1 in the clay soil when equilibrated with deionized water. These values were reduced to 402 and 1088 L kg-1 in chloride solution and 146 and 297 L kg-1 in groundwater for the loam and clay soils, respectively. The increased liquid to solid ratio showed a tendency to increase the distribution coefficient under the trace concentration of cesium. It was observed that an increase in the distribution coefficient of cesium from 1079 to 3312 L kg-1 when the liquid to solid ratio increased from 1:1 to 10:1. Differences in Kd were explained on the basis of ion exchange mechanism and indicate that certain test conditions.
could be adopted by researchers for a precise estimate of the Kd. Such conditions should be corresponded as closely as possible to the natural field conditions.

This study was conducted in order to evaluate the uses of sulfur –rich water found in the Western desert of Iraq an assessment was made to select more suitable procedure for using this type of water without negative health and environmental effects, so a field survey of the wells in area was under taken, measuring its discharge sulfur content. Multi-stage treatment system was made using different material such as fermented wheat straw with A. niger, spent mushroom compost, and calcinated rock phosphate ,limestone inoculated with sulfur oxidizing and reducing bacteria, also using continuous treatment system for different time interval of 12, 24, and 36 hour. The results showed existence of sulfur-rich water in Km70 area was superior in its sulfur content 2000 mg l-1. treatments W1 and W2 removed SO4 and hydrogen sulfide by 66.01 and 64.7, 90.97, and 91.6% respectively. Time interval treatment 24 hour. The values of potential salinity in the case of continuous treatments W1 and W2 for 24 hours approached the rates of 12.15 and 11.66, respectively. The efficiency of continuous treatment unit W1 and W2 for hundred days period approached 72 and 96%, respectively.

A field experiment was conducted in one of gypsum soil private farm in Al-Dour district during autumn season 2019. The study aims to show the effect spray potassium concentration of 0, 2000, 4000, 6000 mg l-1 on growth characters and NPK percentage in popcorn plants var Noor. The experiment was applied by using RCBD with three replicates. The results showed that corn plants which sprayed with 6000 mg l-1 gave the highest significant values in plant height 148.06 cm , leave area 4396.3 cm2, leave area index 4.47, leaves number 14.4, plant dry weight 134 g, NAR 0.001789 g cm-2 day-1, CGR 0.002275 gm day-1 and percentage of K, N, and P of 3.591, 1.9, and 0.424% respectively. There was no significant different between 4000 and 6000 mg l-1 treatments in all studied characters. Therefore the spraying of 4000 mg l-1 was useful to improve growth characters and popcorn plant content of NPK.

A field experiment was conducted at Northwest of Ramadi .Ten inbred lines by using Line×tester mating method. On spring season 2018 seeds were planted, at an thesis crossing between inbreds and tester was done. On fall season 2018 for crosses and parents using RCBD with three replications to evaluate and estimate heterosis. The results of statistical analysis for these parents and their crosses were highly significant differences for all traits. Genetic analysis shows superiority the inbred KR640 was best for plant height 183.16 cm, number of grain/row 34.34 grain and grain yield 148.43 g .The tester A105 gave high value in grain yield was 145.62 g . The cross (B73 × IK8) gave high leaves area 0.511 cm, no of grain per rows 39.21grain and grain yield 217.05 g. The crosses (B73 × IK8) gave highly positive hybrid vigor to better parent and mid parent for no. of grain per rows was %28.21 and %42.24 grain yield was %79.10 and %81.71. we can conclude the possibility of using superior inbreeds to produce hybrids or use selection for it and produce synthetic varieties.

The basin of Gran valley is considered as one of dry valleys in Aljazeera district that belongs to Hit municipality 180 km west Baghdad. Area unit was conformed from some measured quantitative properties. Geomorphological and morphometric properties was used to construct data base relied on topographical maps, satellite image and DEM. Basin topography was studied. These landforms were parted into topological, erosional, sedimentary and carstic origins forms. Furthermore, morphometric properties represented the relationships among factors, corrosion processes and terrestrial phenomena such as area, forms, topography and aquatic drain net. Moreover, longitudinal, cross- sections and natural factors were associated. Results revealed that area of basin was 91.41 km2 which its water flew in Euphrates. The basin was very meandering semi-oval shape. Its river levels were 4 with 121 courses that possessed overall length of 149.7 km.

The variation Wind erosion of soil from place to another, cause the variation of variables affecting its activity, and the research aims to quantify the variables of wind erosion soil in governorate of Taiz, to reveal effect of each of them on wind erosion in governorate, was followed by revealing effect of all these spatial variables combined on wind erosion. , By building model by which all these variables were Merge according their weights. The research methodology was to collect data on each spatial variable related to wind erosion of soil, And processing this data, and deriving the informational layers for each spatial variable using a number of mathematical algorithms in the raster calculator for Arc Map 10.5, Highlighting effect of each spatial variable separately on wind erosion activity in governorate, In preparation for integrating all these spatial variables together by means of a model that shows suitability of soil for wind erosion in governorate according to the impact of all these spatial variables. The results of research found that area of district that was Described a high suitability for wind erosion is 4129.2 km2, or 41.22%, and the area of district that was Described moderate suitability for wind erosion is 2267.4 km2, or 22.63%, and area of district that was Described low suitability for wind erosion 2267.4 km2, or 22.63%, and the area of district that was Described by strong suitability for wind erosion is 461.9 km2, or 4.61%, and the area of district that was Described poorly suitability for wind erosion 275.2 km2, or 2.74% of total area governorate.

In this research, an experimental study has been performed in order to enhance the thermal performance of a double-pass solar air collector by employing extended surfaces. In order to increase the heat transfer area, triangular-shaped fins were mounted on the longitudinal direction of the absorber plate. Four models of the solar air collectors were made of aluminum with different fin configurations. The experiments were carried out at the winter season in the climate of Iraq - Ramadi city with longitude 43.268 and latitude (33.43). The used range of mass flow rate in the experiments was from 0.027 kg/s to 0.037 kg/s. The comparison with previous studies in terms of thermal efficiency showed good agreement where the percentage of error does not exceed 1% between them. The results also provided that the existing of fins was a good technique for enhancing the thermal performance of double-pass solar air collector with a marginal increase in pressure drop. Consequently, it is possible to adopt this kind of solar air collectors for many agricultural applications such as solar dryer.