基于缓释肥的侧条施肥技术对水稻产量和氮素流失的影响

研究了侧条施肥技术条件下不同缓释肥用量对水稻产量和氮索流失特征的影响。与不施肥处理（cK）和农民常规施肥处理（FP）比较，利用侧条施肥技术高缓释肥处理（HF）水稻氮素投入比农民常规施肥处理（FP）降低约40％，水稻产量没有降低，穗粒数和千粒重分别比农民常规施肥处理增加17．0％和16．6％。缓释肥各处理氮素回收率在54．5％-63．5％之间，高于常规施肥处理的36．9％。常规施肥处理田面水NH；和TN在施肥后3d内即可达到最大值，随时间推移下降较快，而高缓释肥处理田面水N0i含量在施肥30d后才降到最低；以尿素为氮源，施肥后的前9d是防止氮素流失的关键时期，以缓释肥为氮源，则前30d是防止氮素流失的重要时期。氮素渗漏淋失主要发生在生育前期，以NOi-N形态为主，占全氮流失量的64．8％-70．3％之间，高缓释肥处理的全氮渗漏损失量（14．86kg·hm。）比当地农民常规施肥处理（23．43kg·hm。）减少8．57kg·hm。。综合考虑水稻产量和环境效益，侧条施肥技术可作为一种资源节约和环境友好的施肥技术在水稻种植上应用。

Effect of Side Bar Fertilization Technology Based on Slowrelease Fertilizer on Rice Yield and Nitrogen Losses

Side bar fertilization technology based on slowrelease fertilizer is recognized as being the most mature environmentfriendly techno!ogy and having good operability by the experts in Japan, but there＇s little application in China. Focusing on the effect on water quality of such typical pollutants like nitrogen（N ） from the irrigated areas in the upper reaches of the Yellow River, we studied the effect of. side bar fer tilization technology based on slow release fertilizer on rice yield and nitrogen losses. There were 5 treatments in this experiment, no fertilizer treatment（CK）, low quantity of slowrelease fertilizer treatment（LF）, middle quantity of slowrelease fertilizer treatment（MF）, high quantity of slowrelease fertilizer treatment （HF） and conventional fertilizer treatment （FP）： The slowrelease fertilizer was used as basal which was provided by ShiKeFeng Chemical Industry CD, LTD and the nitrogen content was 23.0%. We used side bar fertilization machine which was introduced by Japanese experts to transplant rice on June 14 and the harvest time was September 26. The results were as follows：the side bar fertilization technology based on high quantity of slowrelease fertilizer treatment （HF） reduced the amount of nitrogen applied by approximately 40% compared to conventional fertilizer treatments （FP） but had no remarkable effects on rice yields while the number of ear and the weight of thousand ear of rice were increased 17.0% and 16.6% respectively. The nitrogen recovery of slowrelease fertilizer treatments were from 54.5% to 63.5% which were higher＇than conventional treatment. The concentration of NH and TN in surface water peaked before the third day after fertilizer application. The NO3 amount in surface water of high quantity of slowrelease fertilizer treatment（HF） brought down to the lowest level after 30 d. When compared with high quantity of slowrelease fertilizer treatment（HF）, conventional fertilizer treatments（FP） decreased even more rapidly with the time. When urea used as nitrogen sources, the first 9 d after urea applied was the critical period to reduce nitrogen loss, and within one month was important time to prevent nitrogen loss as use slowrelease fertilizer. The critical occurrence time of leaching and nitrogen loss was within early stage, and NO_3-N was the main form of nitrogen loss, which accounted for from 64.8% to 70.3%. Total nitrogen loss amount of high quantity of slowrelease fertilizer treatment（HF） was 8.57 kilogram fewer than conventional fertilizer treatments（FP） per hectare. Considering the rice yield and environmental effects, side bar fertilization technology based on slowrelease fertilizer is one of environmentfriendly technology that can be applied in rice cultivation.