Effect of Soil Salinity for Ecological Restoration in the Reclaimed Area of Seasides

임해매립지의 생태계 복구를 위한 토양중 염류의 활성도 분석

  • Published : 1999.06.30

Abstract

This study was carried out to obtain reasonable management method of salt-affected soil for ecological restoration in the reclaimed land. Chemical properties of reclaimed soil was investigated base on reclamation years. Ionic acitivity in soil and satruration extract were analyzed to estimate the effect of salt interception by planting ground treatment. The soil porperties of reclaimed land was saline-sodic soil with $11.3dSm^{-1}$ of electrical conductivity, 34.8% of exchangeable sodium percent in first reclamation year. Electrical conductivity, exchangeable sodium and exchangeable chlorine were remarkedly decreased during six years after reclamation but chemical properties of reclaimed soil was unsuitable status for tree growth. Exchangeable sodium perecnt was higher in the neighborhood parks and street tree sites than in the buffer green spaces and was higher in subsoil than in topsoil of profile in all sites. Content of soduim, chloride and sulfate in saturation extract were more than other ions. Content of soduim and chloride were higher in the neighborhood parks and street tree sites than in the buffer green spaces and were higher in subsoil than in topsoil. Content of calcium plus magnesium of soil was higher in the buffer green space than in the neighborhood park and street tree but content of calcium and magnesium in saturation extract were higher, as result from exchangeable sodium, in the neighborhood parks and street tree sites than in the buffer green spaces. Concentration of salt in soil showed the difference with mounding height and planting ground treatment. The lowest concentration of salt appeared in buffer green spaces and street tree sites was the highest. Salt interception by mounding height in the same planting ground treatment was more effective 120cm of mounding height than 70cm of mounding height.

본 연구는 임해매립지에서 생태적인 복구를 위한 토양관리 방안을 제시하기 위하여 매립특성에 따라 준설매립지역에서 매립연도를 구분하여 준설토의 화학적 특징을 조사하였고, 수목이 염류에 피해를 받지 않도록 여러 가지 식재기반을 조성한 후 조성방법에 대한 염류차단 효과를 검토하였다. 준설초기의 토양은 침출용액의 pH 7.5, EC $11.3{\sim}10.6dSm^{-1}$ 치환성나트륨백분율이 34.8~35.2%로 알칼리성염류토양의 특징을 나타냈고, EC, 치환성 $Na^+$, $Cl^-$의 양은 매립 후 6년까지 현저하게 감소되었으나 토양의 화학적 특성은 수목이 생장하기에는 아주 부적절한 조건을 가지고 있었다. 식재기반 조성지에서 토양중 치환성나트륨백분율은 표층보다 심층에서 높았으며, 완충녹지보다 근린공원과 가로수지역에서 높게 나타났다. 토양포화침출용액에서 $Na^+$, $Cl^-$$SO_4^{2-}$의 농도는 다른 이온들보다 높았고, $Na^+$, $Cl^-$의 농도는 표층보다 심충에서 증가하였으며, 완충녹지보다 근린공원과 가로수지역에서 높았다. 토양중 $Ca^{2+}+Mg^{2+}$ 함량은 근린공원과 가로수지역보다 완충녹지에서 높았으나 토양 포화침출용액내 $Ca^{2+}+Mg^{2+}$ 함량은 완충녹지보다 근린공원과 가로수에서 높았는데 이는 토양중 치환성 $Na^+$ 함량 차이에서 기인되었다. 따라서 임해매립지의 식재기반 조성방법에 대한 염류차단효과는 완충녹지가 가장 높았으며, 가로수지 역에서 염분농도는 가장 높게 나타났다. 그리고 동일한 식재기반 조성에 대하여 성토높이에 따라서 염분차단 효과는 다르게 나타나 성토 높이가 70cm보다 120cm인 지역이 토양중 염분농도가 낮았다.

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Acknowledgement

Supported by : 한국과학재단