نوع مقاله : مقاله پژوهشی
نویسندگان
1 دانشجوی کارشناسی ارشد، دانشگاه گیلان
2 دانشیار دانشگاه گیلان
3 دانشجوی دکتری دانشگاه تهران
چکیده
کلیدواژهها
عنوان مقاله [English]
نویسندگان [English]
Understanding the factors affecting water and solute movement in the soil profile and the use of new amendments like biochar can help the proper management to reduce nitrate leaching from the root zone and prevent the pollution of underground waters. This research was conducted to study the effect of rice husk biochar of two sizes (natural and finer than 1 mm) in two application rates (1% and 3%) in the presence and absence of compost (1 %) on nitrate leaching in a clayey soil during a five months period. The experiment was based on completely randomized design with three replications. The biochar was produced from rice husk under pyrolysis condition at 500 °C under limited oxygen condition. The pots were subjected to wetting (field capacity plus 20 percent) and drying (permanent wilting point) cycles, and nitrate concentration was measured monthly in the bottom outflow. The highest and least rates of nitrate leaching were observed in the treatment that contained compost-without biochar and the treatment containing biochar without compost, respectively. Biochar addition to the soil at both rates and both sizes significantly reduced nitrate leaching compared to the control during the whole time. In overall, nitrate leaching was higher in the treatments containing compost compared to those without compost. The particle size of biochar had no effect on its efficiency of nitrate leaching. Nitrate leaching showed a drastic reducing trend during the first three months and had an increasing trend in the last two months.
کلیدواژهها [English]
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