Abstract
To verify that the electrokinetic remediation is effective for decreasing salinity of fields of the plastic-film house, field tests for physical property, chemical property, and crop productivity of soils have been conducted. The abridged result of those tests is as follows. In the EK treatment, the electrokinetic remediation has been treated at the constant voltage (about 0.8 V $cm^{-1}$) for fields of the farm household. At this time, an alternating current (AC) 220 V of the farm household was transformed a direct current. The HSCI (High Silicon Cast Iron) that the length of the stick for a cation is 20cm, and the Fe Plate for an anion have been spread out on the ground. As the PVC pipe that is 10 cm in diameter was laid in the bottom of soils, cations descend on the cathode were discharged together. For soil physical properties according to the EK treatment, the destruction effect of soil aggregate was large, and the infiltration rate of water was increased. However, variations of bulk density and porosity were not considerable. Meanwhile, in chemical properties of soils, principal ions of such as EC, $NO_3{^-}$-N, $K^+$, and $Na^+$ were better rapidly reduced in the EK treated control plot than in the untreated control plot. And properties such as pH, $P_2O_5$ and $Ca^{2+}$ had a small impact on the EK. For cropping season of crop cultivation according to the EK treatment, decreasing rates of chemical properties of soils were as follows; $NO_3{^-}$-N 78.3% > $K^+$ 72.3% > EC 71.6% $$\geq_-$$ $Na^+$ 71.5% > $Mg^{2+}$ 36.8%. As results of comparing the experimental plot that EK was treated before crop cultivation with it that EK was treated during crop cultivation, the decreasing effect of chemical properties was higher in the case that EK was treated during crop cultivation. After the EK treatment, treatment effects were distinct for $NO_3{^-}$-N and EC that a decrease of nutrients is clear. However, because the lasting effect of decreasing salinity were not distinct for the single EK treatment, fertilization for soil testing was desirable carrying on testing for chemical properties of soils after EK treatments more than two times. In the growth of cabbages according to the EK treatment, the rate of yield increase was 225.5% for the primary treatment, 181.0% for the secondary treatment, and 124.2% for third treatment compared with the untreated control plot. The yield was increased by a factor of 130.0% for the hot pepper at the primary treatment (Apr. 2011), 248.1% for the lettuce at the secondary treatment (Nov.2011), and 125.4% for the young radish at the third treatment (Jul. 2012). In conclusion, the effect of yield increase was accepted officially for all announced crops.
전기동력학적인 기술 처리가 시설재배 토양의 염류제거에도 효과를 보이는가를 검증하기 위하여 토양의 물리성, 화학성 및 작물생산성을 조사한 포장시험한 결과를 요약하면 다음과 같다. EK처리는 농가포장에 220 V 농가용 교류를 직류화하여 약 0.8 V $cm^{-1}$의 정전압으로 동전기 처리 하였다. 양전극의 길이는 20 cm로서 고규소철 (HSCI; High Silicon Cast Iron), 음전극은 철판 (Fe Plate)을 바닥에 깔았다. 하단부 흙 속에는 직경 10 cm 정도의 유공 PVC파이프를 매설하고 음 (-)극으로 몰려온 양 (+)이온들을 모아서 배출시켰다. EK처리에 따른 토양 물리성은 토양입단의 경우 파괴 효과가 크고 물의 침투 속도는 증가되었으나, 용적밀도와 공극율의 변화는 적었다. 한편, 토양의 화학성을 보면, 무처리구보다 EK처리구의 EC, $NO_3{^-}$-N, $K^+$, $Na^+$ 등의 주요 이온들이 급격히 감소되었고, pH, $P_2O_5$, $Ca^{2+}$ 등은 EK의 영향력이 적은 성분이었다. EK처리에 따른 작물재배 작기별로 토양화학성 감소율을 비교한 결과 $NO_3{^-}$-N 78.3 % > $K^+$ 72.3 % > EC 71.6 % $$\geq_-$$ $Na^+$ 71.5 % > $Mg^{2+}$ 36.8 %순 이었다. EK를 작물재배 이전 즉 휴경을 하면서 처리한 시험구와 작물을 재배하면서 EK를 처리한 시험구의 화학성 감소효과를 비교한 결과 작물재배 중 처리효과가 더 높았다. EK처리 후 양분의 감소가 뚜렸한 $NO_3{^-}$-N, EC 등은 처리효과가 분명하였으나, 1회의 EK처리만으로는 염류감소 지속효과가 분명하지 않으므로 2회 이상 EK처리 후 토양화학성 검정을 계속하면서 토양검정 시비를 실시하는 것이 바람직하였다. EK처리에 따른 배추생육을 보면 1차 처리 - 2차 처리- 3차 처리구의 무처리 대비 증수율은 225.5 % - 181.0 % - 124.2%로 각각 나타났다. 1차 처리 (2011.4)시 고추는 130.0 %, 2차 처리 시 상추는 248.1 %, 3차 처리 시 열무는 125.4 % 각각 증수됨으로서 공시되었던 모든 작물에서 증수효과가 인정되었다.
