【摘要】 【目的】探讨稻草还田免耕对稻田土壤剖面氮、磷和钾的影响。【方法】对连续2年和7年结合稻草还田常耕抛秧和免耕抛秧试验的水稻土剖面氮、磷、钾进行了研究。【结果】免耕表层0—4(5)cm土壤全氮、全磷、碱解氮和速效磷含量显著高于常耕土壤。稻草还田免耕0—4(5)cm土壤的全钾含量显著高于常耕土壤,速效钾含量与稻草还田常耕差异不明显,但显著高于普通常耕土壤。免耕5—20 cm层土壤全氮、全磷、全钾、碱解氮和速效磷含量低于常耕土壤。普通免耕Aa层(耕作层)土壤速效钾含量显著低于常耕土壤。免耕的Ap层(犁底层)、W层(潴育层)和C层(母质层)碱解氮和速效钾含量高于常耕土壤。【结论】稻草还田免耕抛秧协调土壤氮、磷和钾的效果比普通免耕好,有利于土壤肥力的提高,稻草还田免耕抛秧是稻田免耕栽培的发展方向。更多还原

【Abstract】 【Objective】The objective of this study was to understand the effects of no-tillage and rice-seedling casting with rice straw returning on nitrogen,phosphorus and potassium of paddy soil profile.【Method】Contents of nitrogen,phosphorus and potassium of paddy soil profile soil of conventional tillage of rice-seedling casting and no-tillage of rice-seedling casting experiments that lasted two and seven years were investigated.【Result】Contents of total nitrogen,total phosphorus,alkaline-hydrolysable nitrogen and rapidly available phosphorus in 0-4(5) cm soil layer of no-tillage treatments were higher than those of conventional tillage.Contents of total potassium in 0-4(5) cm soil layer of no-tillage with rice straw returning treatment were significantly higher than those of common conventional tillage.Contents of rapidly available potassium in 0-4(5) cm soil layer of no-tillage with rice straw returning treatment were lower than that of conventional tillage with rice straw returning,but significantly higher than that of common conventional tillage.Contents of total nitrogen,total phosphorus,total potassium,alkaline-hydrolysable nitrogen and rapidly available phosphorus in 5-20 cm soil layer of no-tillage treatments were lower than those of conventional tillage.Content of rapidly available potassium in Aa layer(cultivation layer) of common no-tillage treatment was lower than those of conventional tillage.Contents of alkaline-hydrolysable nitrogen and rapidly available potassium in Ap layer(plow pan),W layer(waterlogged layer) and C layer(parent material layer) were higher than those of conventional tillage.【Conclusion】The effects of no-tillage of rice-seedling casting with of rice straw returning on coordinate soil nitrogen,phosphorus and potassium are superior to that of common no-tillage of rice-seedling casting,and no-tillage of rice-seedling casting with rice straw returning is advantageous to the improvement and development of soil fertility.No-tillage of rice-seedling casting with rice straw returning is a development direction of paddy field no-tillage.更多还原