The Plant Community of Nanjido, a Representative Nonsanitary Landfill in South Korea: Implications for Restoration Alternatives

Vegetation and soil analyses of the slopes of the Nanjido, a nonsanitary landfill in South Korea, were conducted to investigate the colonization status of plant communities, and to suggest restoration alternatives by comparing the vegetation of the landfill and the nearby forests. The vegetation of the Nanjido landfill and the control sites was surveyed by using 10 ×: 10 m quadrats. The soils were analyzed for pH, electrical conductivity, organic matter content, Total-N, P, K, Ca, Mg, sand, silt, and clay. Canonical correspondence analysis (CCA) was performed by using the extent of cover for all the recorded species, and the physical and chemical variables of soil. Salix babylonica, Platanus orientalis, Rosa multiflora, Prunus persica,Albizzia julibrissin, Indigofera pseudo-tinctoria, Robinia pseudoacacia, Amorpha fruticosa, Ailanthus altissima, Forsythia koreana, and Paulownia tomentosa were the commonly found tree species.Quercus mongolica, considered to be the natural late successional species of temperate South Korea, was recorded at the Nanjido landfill. Levels of pH, the electrical conductivity and concentrations of P, Ca, and Mg in landfill soils were significantly higher than the forest control site soils (P < 0.05). In CCA ordination space, landfill quadrats clustered in less acidic soils, rich in Ca and Mg, while forest control site quadrats clustered in acidic, low P soils. This study found several indications that it is possible for a nonsanitary landfill to support succession to typical and natural forests. In addition, the landfill slope vegetation could function as a biological source for the restoration of the other landfill areas that remain barren, if planned efforts are made for conservation and rehabilitation.