Energy Balance in Various Management of Paddy Ecosystem

논 생태계 관리방법에 따른 에너지 수지

A set of surveys was performed at Chungchongbuk-Do in 1997 in order to analyze energy related in rice production. Four cases in rice farming were surveyed : traditional farming, no chemical farming, duck farming, mud snail farming. The farmer in traditional fanning has used chemical fertilizers and chemicals such as general farmers. The farmer in no chemical farming has used chemical fertilizers and manure but has not use chemicals. The farmer in duck farming has not used chemical fertilizers and chemicals but brought up duck in paddy. The farmer in mud snail has not used chemical fertilizers and chemicals but brought up mud snail in paddy. The animals n paddy as like duck and mud snail not only eat weeds and insect but also input fertile material by excretion. The results of energy analysis are as follows 1. In view of energy, the duck farming was the most efficient of four cases. The mud snail farming was less efficient than the duck farming, the traditional farming was less efficient than the mud snail farming, the na chemical farming was less efiicierrt than the traditional farming. 2. Relatively to amount of product, non renewable energy was used more in traditional farming than other cases and renewable energy was used more in no chemical farming than other cases. 3. The reason of low energy efficiency in the no chemical farming was to input fertilizers and manure so much. So to input nutrients excessively in order not to use chemicals can make rice farming to be inefficient in a view of energy. 4. The farming to bring up animals in paddy was more sustainable than other cases because input of non renewable energy could be decreased. But in order to make it to be more sustainable, should be developed cultivation method to decrease input of non renewable direct energy such as fossil fuel and electricity .

충청북도 일대에서 화학비료와 농약을 사용하는 일반적인 경작논(이하 일반논), 화학비료, 퇴비를 사용하지만 농약을 사용하지 않는 논(이하 무농약논), 농약과 화학비료를 사용하지 않고 논에 오리를 사육하는 논(이하 오리논), 농약과 화학비료를 사용하지 않고 논에 열대산 우렁이를 사육하는 논(이하 우렁이논)에 대해 에너지 분석을 실시하여 다음과 같은 결과를 얻었다. 에너지 효율은 오리논(1.8)이 가장 높고 우렁이논(1.5), 일반논(1.0), 무농약논(0.5)의 순서이다. 생산량에 비해 상대적으로 재생 불가능한 에너지는 일반논과 무농약논이 오리논과 우렁이논보다 2-3배 많이 사용하였고 재생가능한 에너지는 무농약논이 가장 많이 사용하였다. 무농약논은 비료, 퇴비를 과도하게 사용하여 에너지 효율이 낮아졌다. 무농약 재배를 위한 과도한 영양분의 투입은 에너지 측면에서 비효율적일 수 있음을 보여주었다. 논에 동물을 사용하는 방식은 재생불가능한 에너지 투입을 줄일 수 있어서 다른 방식에 비해 친환경적이었다. 하지만 보다 환경적이고 지속가능하기 위해서는 재생 불가능한 에너지를 더 줄일 수 있는 방안에 대한 연구가 필요하다.