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Abstract The status of the available ( TPA-extraetrable) micronutrients (Fe, Mn, Zn and Cu) in the soil under sali ity condition was investigated. Studies envalved a survey study of 48 soil samples, 40 plant samples (barley and cabbag) and 20 saline water sample collected from parts of Egypt irrigated with saline waters, and relating resul s of salinity with micronutrients in soils and plants. It also envolved 3 greenh use pot experiments (60-day duration) under conditions of variable salinity an organic matter additions. Experiment 1 envolved irrigati sorghum plant grown in a non-saline clay loam with a non-saline water a d a saline water (EC of 0.32 and 4.01 dS/m respectively). Experiment 2 envolved cultiva ing sorghum plant in a non-saline soil (the same soil of experiment 1) and a line soil (both being clay loam, with EC of saturation extrac( of: 3.16 dSI and 12.20 dS/m) both irrigated with the non-saline water (of 0.32 dS/m). Experiment 3 envotved cultivatin barley plant in a non saline clay soil (EC= 1.35 dS/m ”saturation extractfl ) i igated with two agricultural drainage waters (a diluted and non diluted sali e drainage water) having salinity levels of 7.22 and 14.36 dS/m. resp ively and under no-leaching (LO)or different leaching fractions; (half of th leaching (l1) or full value of the leaching (l2) requirements); leachates were collected (ymere leaching was allowed). A treatment having irrigation ’th distilled water (Withno leaching) was conducted. Results may be summarized as Ii 1. Survey study: Soils irrigated with ’cultural drainage water and well . water) showed greater! available Fe. no trend with regard to Mn, Zn or Cu. Increased Fe availability was 8S!~ated mostly with soil organic matter followed by soil salinity. -------~--------- I ------~~ ~ .__ 110 2. Pot experiments: 2.1. Dry weight of plants and micronutrient uptake: Salinity of irrigation water decreased dry weight of sorghum or barley plants and also decreased uptake of micronutrients. 2.2. Iron in soil and leachate. Irrigating the non-saline soil with saline water gave greater available Fe, while the saline soil irrigated with non-saline water contained less inherent available Fe. Under irrigation with saline waters and leaching conditions, soils conta(ned less available Fe, and more intense leaching was associated with gre~ter amount of Fe found in leachates. 2.3. Manganese in soil and leachate. There was more available Mn in the soil irrigated with saline water. The lower contents of available Mn in the saline soil was a reflection of the basic differences between the two soils. Under conditions of irrigation with saline water, the soil contained more available Mn. Allowing leaching caused a decrease in soil available Mn and leachates contained more Mn. 2.4. Zinc in soil and leachate. There was less available Zn in the soil under irrigation with saline water, as well as lower’ contents of available Zn in the saline soil. The successive increasing of water salinity caused more available Zn in the soil, while under leaching conditions there-was less availab,e Zn due to more Zn removal from the soil. 2.5. Copper in soil and leachate. There was slightly less available Cu in the soiUrrigated with saline water. The saline soil Contained higher available Cu. .Under irrigation with saline water and leachinQconditions1 less available Cu was found. This was due to the losses of Cu by leaching. |