为明确东北黑土区稻田土壤氮素渗漏规律, 在典型黑土区开展了基于农田水平衡的小区试验, 分析了不同灌 溉方式和施氮水平条件下稻田土壤渗漏水中三氮浓度变化情况, 并结合农田水平衡方程计算出了不同水肥条件下 的氮素淋失总量。结果表明, 渗漏水中铵态氮、硝态氮和总氮浓度与施氮量呈正相关关系, 控制灌溉和浅湿灌溉分 别可以减少硝态氮渗漏浓度111 89%和141 15%; 常规灌溉方式下每公顷每增加1 kg 施氮量( 折合成纯氮) , 氮素淋 失量增加01 117 5 kg , 控制灌溉和浅湿灌溉则分别增加01 035 9 kg 和01 055 7 kg ; 在水稻全生育期, 控制灌溉氮素淋 失总量最小, 平均为41 51 kg / hm2 , 约是常规灌溉的1/ 3、浅湿灌溉的1/ 2。综合分析认为, 浅湿灌溉是适用性更高 的灌溉方式, 理论合理施肥量为1371 30 kg / hm2 。

In o rder t o clarify the r ea lit ies of nitr og en leakage in paddy so il in black soil a rea o f No rtheast China and to under stand nitro gen mig ration patt ern, a dist rict ex per iment al was dev eloped in ty pical black district based on farmland w ater balance, so as to contr ol the nit rog en leakag e and r educe g roundw ater pollution threat. T he three nitro gen co ncentration chang es in leakag e water of paddy so il under different ir rigation and nit rog en level conditio ns w ere analyzed, and the to tal amo unt of nitr og en leac2 hing in different treatment was calculated using the w ater balance equat ion. Result s show ed that the co ncentrat ions o f ammoni2 um nitro gen, nitr ate nitrog en and to tal nitr og en in the leaching water w ere positively co rr elated wit h nitr og en applicatio n a2 mo unt. Co nt ro l ir rigation and wet2shallow irr igat ion can r educe 11. 89% and 14. 15% of nit rate leakage co ncentration, respec2 t ively. Nitr ogen leaching amount incr eased 0. 117 5 kg per hectare with each addit ional kilo g ram o f nitr og en ( conv er ted into pur e nitro gen) w hen using normal ir rigation, it w as r espectiv ely 0. 035 9 kg and 0. 055 7 kg for contr ol irr igation and w et2shallow ir2 rig atio n. The nitro gen leaching loss in w ho le g row th per iod under contr ol irrigation w as the least, av erag e at 4. 51 kg # hm22 , and it is r espectiv ely 1/ 3 and 1/ 2 of that under no rmal irr ig ation and w et2shallow ir rig atio n. Wet2shallow ir rig atio n w as mo re appli2 cable, and the most reasonable theor etic fertilizer amo unt is 137. 30 kg # hm22 .

国家水体污染控制与治理科技重大专项/ 国家水环境安全战略若干问题研究0 ( 2012ZX07601001)