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The pollution of agricultural soils, water and plants by trace elements (TEs) in the Nile Delta Region, Egypt, is of great importance. This study aimed to investigate the spatial and seasonal variation of some TEs in the agricultural area adjacent to Kitchener Drain and to evaluate the ecological risk posed by these elements using six indices. Soil and plant samples were collected from seven sites close to the drain, while water samples were collected from the corresponding sites inside the drain during three seasons (winter, spring and fall). The results showed that all studied TEs in the soil varied seasonally and spatially among the locations around the drain. Most of the studied elements in the soil were higher in the southern and middle area around the drain. All studied elements in the soil were also higher in the winter than other seasons. Nickel and lead were almost non-detected during all seasons in plant tissues, while other elements were higher in the winter than other seasons. In contrast to the soil and plant tissues, water samples demonstrated lower or non-detected levels of TEs. The results also indicated that the values for the risk assessment indices differed among the studied TEs. Therefore, there is a risk of increasing the concentration of some metals in the study area due to anthropogenic pollution from the adjacent polluted drain through irrigation with contaminated water and spreading of contaminated dredged materials on agricultural fields.

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The objective of this investigation was to study the effect of addition of organic matter i.e, composted rice straw, compost tea and their interaction on the yield and seed nutrients content of faba bean (vicia faba L.) cv. Sakha 1 and some soil biological and chemical properties. A field experiment was conducted in the Experimental Farm of Sakha Agric. Res. Station in two successive winter seasons of 2010/2011 and 2011/2012. Results showed that soil organic matter content was increased, while values of soil salinity (ECe) were reduced and there was a slight reduction in soil pH with compost addition at rates 2 and/or 4 tons/fed. Data recorded the highest significant increases in nodule numbers and its dry weight as compared to control. Also, these treatments recorded significant increases the biological activity of soil in terms of increasing the soil total bacteria, as well as dehydrogenase activity and nitrogenase activity that increase the soil fertility, improved plant quality, as well as environmentally safe and eco-friendly, that positively turn on faba bean yield production. The interaction between compost and compost tea gave better results in increasing the seed yield especially for application of 4 tons /fed with compost tea spraying at 50 days after sowing increased the seed yield by 51%, 53.1% relative to control in the two seasons (2010/2011 and 2011/2012), respectively. Nutrients content (N, P and K) of faba bean seeds was significantly increased in all treatments compared with the control. Also, the results showed that application of rice straw compost was effective for increasing available N, P and K in soil as compared to the control. Based on the results of the current study, the combinations between rice straw compost and compost tea are considered as an integrating nutrient management to improve the soil biological and chemical properties and yield of faba bean crop.

FIELD TRAILS were conducted at Sakha Agricultural Research Station (El-Hamrawy Farm), Kafr El-Sheikh Governorate in salt affected soils. Growth cycle included rice and wheat. Rice was applied for three successive seasons (2013-2013/2014 and 2014).The soil was treated with gypsum, mole drain, farmyard manure and biofertilizer combined with different sources of nitrogen (urea, ammonia gas and ammonium sulphate). The highest rates of salt leaching were achieved with the application of gypsum combined with the injection of ammonia gas followed by the application of gypsum plus urea or gypsum plus urea and biofertilizer. The soil sodicity decreased after three seasons with all treatments combined with different nitrogen sources. Application of gypsum combined with the construction of mole drain at 4 m spacing, ammonia gas, farmyard manure and biofertilizer had the highest value of infiltration rate at the end of the growth cycle compared with the values before starting the experiment, while the application of gypsum plus biofertilizer and urea produced the lowest infiltration rate. The bulk density and total porosity were positively affected by the application of gypsum, mole drain combined with ammonia gas, farmyard manure and biofertilizer. The application of gypsum plus farmyard manure and ammonia gas or mole drain at 4 m spacing combined with biofertilizer, farmyard manure and ammonia gas increased the yield and irrigation water use efficiency of rice and wheat.