Biochar and Wheat straw effect on nitrogen leaching concentration

Given the limited availability of water resources, population growth and hygiene, maintaining a groundwater resources with good quality is important. Agriculture and the continued use of fertilizer in cultivated lands lead to contamination of groundwater resources. The aim of this study was to investigate the effect of application and amount of biochar and straw application on nitrate and nitrite leaching. This study was based on a randomized complete block design with treatments: control (CO), Wheat straw 5 mm thick (SM5), Wheat straw at 10mm (SM10), Straw at a rate of 5 ton / ha (ST5), Straw at a rate of 10 ton / ha(ST10), Biochar at a rate of 2.5 ton / ha (BT2.5) and Biochar at a rate of 5 ton / ha (BT5). Results showed that biochar and straw application had significant effect on nitrate and nitrite leaching at 95% level. The highest decrease in cumulative nitrate concentration occurred in BT2.5 treatment (23%). Whereas in ST10 treatment the concentration of cumulative nitrate increased (64%). Nitrite content in all treatments decreased during the cultivation period and the highest decrease in cumulative nitrite concentration occurred in BT5 treatment (94%). The use of biochar and straw leads to a decrease in the concentration of cumulative leaching nitrite. Biochar application reduces leaching nitrate concentration and straw application as a more effective layer than its combination with soil (ton / ha).