نوع مقاله : مقاله پژوهشی
نویسندگان
1 عضو هیات علمی مرکز تحقیقات کشاورزی و منابع طبیعی خراسان
2 استاد دانشکده کشاورزی دانشگاه فردوسی مشهد
3 دانشجوی سابق کارشناسی ارشد دانشکده کشاورزی دانشگاه فردوسی مشهد
چکیده
کلیدواژهها
عنوان مقاله [English]
نویسندگان [English]
In order to evaluate the residual amounts of nitrogen, phosphorus and potassium in soil in response to different rotations and conventional and ecological cropping systems, an experiment with split-plot design, based on complete randomized block arrangement with 3 replications, was conducted for 6 years. Main plots were assigned to different rotations, including wheat-wheat, and corn-wheat and sugar beet-wheat. Sub plots were assigned to different cropping systems including high-input, medium-input, low-input, integrated (with moderate input) and organic (without any chemical input). Results showed that the amount of macronutrients in surface soil layer varied with rotations and cropping system, whereas. The amount of residual N in soil was reduced, residual P and K increased in 6 years. Also soil analysis showed that the residual amounts of soil nutrients in organic and integrated systems were greater than those of conventional system. The residual amount of macronutrients was affected significantly by different rotations. The electrical conductivity of saturated extract in integrated system was the highest and those of the high-input, medium-input and low-input systems were of medium, and the organic system was at the lowest level by comparison.
کلیدواژهها [English]