Abstract
This study was carried out to investigate the effects of the complex fertilizers containing polyaspartic acid (PAA) on growth and $CH_4$ emission in rice field and optimum application rate of the fertilizer compared to the standard recommended application rate (control). The PAA-containing complex fertilizers (PCF) were applied at 55, 65 and 75% levels of standard recommended application rate (control). The application rate of PAA in the plot of every PCF treatment was 150g ai/10a. The PCF was applied as a basal dressing without topdressing at tillering stage. The growth parameters of rice and its nitrogen use efficiency treated with PCF at a 65 to 75% level were not different compared with those of control, and the rice yield was also not significantly different between PCF at a 65 to 75% level and control during 2 years(2010~2011) field experiment. And the $NH_4$-N content in soil was not affected by 65% to 75% level of PCF treatment. Considering overall research results such as rice yield and growth parameters PCF is not significantly different with the control and the optimum application rate of the PCF as a basal fertilization was determined to be 65~75% of the standard application rate based on the result in rice cultivation. Moreover, $CH_4$ emission rate was significantly reduced by PCF treatments, showing 216 kg and 229 kg $CH_4/ha$ at 65% and 75% PCF treatment level, respectively, compared to 266 kg $CH_4/ha$ of the control.
본 연구는 논토양에서 벼 재배시 PAA(Polyaspartic acid)가 함유된 복합비료의 시용효과를 살펴보고자 2010년부터 2011년까지 고시히카리를 시험품종으로 재배시험하여 벼 생육 및 메탄 배출량으로 검토하였으며, 적정 시용수준을 설정하였다. 1. 벼 식물체중 질소함량은 표준시비구와 전용복비 N 65%, N 75% 해당량 처리구와 대등하였고, 초장 및 분얼수 등 생육상황도 같은 경향이었다. 2. 전용복비 N 65%와 75% 해당량 처리구의 토양 중 $NH_4$-N 함량은 표준시비구와 대등하였다. 3. $CH_4$ 배출량은 표준시비구 266 kg $CH_4/ha$에 비해 전용복비 N 65% PAA 시용구에서는 19%, N 75% PAA 복비 시용구에서는 14% 감축되었다. 4. 표준시비구와 쌀수량이 대등한 전용복비의 시용수준은 표준시비의 N 65%, 75% 해당량의 전용복비 처리구이었다. 5. 농가실증 2개소 모두 관행비료와 개발비료(관행 N 75% 해당량)의 생육, 수량 및 미질 조사결과 대등하였다.
