Nitrate leaching through soils via application of organic manures of poultry, cow and sludge

作者：Mashal M^*; Larijani N Nikamal; Hassanoghli A; Liaghat A; Varavipour M

来源：Research on Crops, 2012, 13(2): 545-551.

• Lysimeter
• nitrate leaching
• organic manures
• water pollution

The application of chemical fertilizers and organic manures, without considering their side effects cause problems to human health and environment. Nitrate is one of the most important elements of organic manures which its behaviour should be monitored because it can leach through soil to surface and ground waters by irrigation or precipitation. The main object of this study was to determine the nitrate transport via application of organic manures. Experiments were carried out in lysimeters to enable us to control all factors. Lysimeters were cylindrical drained plastic barrels with 100 cm height and 60 cm diameter which were filled by uncondensed soil up to 60 cm height. Two different soil textures, loam and silt loam, were used. Three different organic manures (poultry, cow and sewage sludge) were applied by the rate of 35 t/ha. Twenty-four lysimeters were arranged; nine lysimeters for three types of manure with three replicates and three without manure used as control for each soil type. Each lysimeter irrigated by well water three times with one week interval. Drain water samples (100 ml each sample) were taken through the pore volume drained away after irrigating of lysimeters during five times. Each pore volume was divided into five equal parts and the first one was chosen. The results were analyzed by the statistical factorial experiment in a completely randomized design. The results revealed that the nitrate concentration in loam soil was more than silt loam soil in drain water samples, so it can be ascribed to the effect of soil texture. Sewage sludge treatment caused the most nitrate concentration in drain water samples for both soil textures, and the least was monitored in control treatment. The nitrate concentration for poultry and cow manure were between them, respectively. By one week irrigation intervals and three consecutive irrigations, the amount of contamination was highest in the first week and was the lowest in the third week in both the soils; it can be related to nitrate leaching by irrigations done.

• 出版日期2012-8