In order to evaluate the effect of various organic soil conditioner ratios on the soil moisture content and growth of Cotoneaster horizontalis, a container type for wall-planting experiment was conducted in a greenhouse at Konkuk University under non-irrigation. The experimental planting grounds were prepared with different organic soil conditioner ratios (A1L0, A8L1, A4L1 A2L1 and A1L1), and a drought-tolerant ornamental variety of Cotoneaster horizontalis was planted. The change in soil moisture content, plant height, number of branches, number of dead leaves, number of leaves, number of shoots, length of node, length of leaf, width of leaf, root-collar caliper, chlorophyll content, and survival rate were investigated, from April to Jun 2010. The results of soil moisture content measurements were analyzed with weight units in the container type for wall-planting during the dry summer season. The soil moisture contents were significantly enhanced in the container type for wall-planting in increasing order as the amount of soil conditioner level was increased (A1L1> A2L1> A4L1> A8L1> A1L0). Compared to the control treatment application (amended soil with 100% + organic soil conditioner 0%), the highest plant growth was observed in the treatment of A1L1 application (amended soil with 50% + organic soil conditioner 50%). However, the differences between the organic soil conditioner ratio treatments of A1L1, A4L1, and A8L1 organic soil conditioner application were mostly not significant. The survival rate increased with the increasing application of organic soil conditioner, but in the control treatment application all the plants died. The experimental results from clearly demonstrated that the organic soil conditioner improved the survival rate more than the growth of Cotoneaster horizontalis. Therefore, Cotoneaster horizontalis is expected to be a highly valuable shrub for green wall systems, when considered for us in integration system or for increasing soil water contents in planting grounds.

본 연구는 무관수 옥상녹화시스템 식재기반 차이에 따른 돌나물의 생육 변화를 살펴보고, 적합한 토심과 토양배합비를 제시함으로써 무관수 옥상녹화 식물소재로 활용성을 높이고자 수행하였다. 토심(15㎝, 25cm)과 토양배합비(SL, P7P1L2, P6P2L2, P5P3L2, P4P4L2)를 각각 다르게 실험구를 조성하였으며, 내건성이 뛰어난 돌나물을 식재한 후 초장, 녹피율, 엽록소 함량, 생체중과 건조중 등 생육변화를 측정하였다. 토심 15㎝처리구에서 토양배합비에 따른 돌나물의 초장은 인공배합토가 자연토보다 높았으며, 인공배합토 중 P5P3L2에서 초장이 가장 길었다. 토심 25㎝처리구도 같은 경향을 나타내었다. 녹피율과 엽록소함량은 경우 자연토보다 인공배합토에서 대체로 높았으나, 토심에 따른 차이는 뚜렷하지 않았다. 생체중과 건물중은 토심 25cm가 토심 15cm보다 높았으며, 인공배합토가 자연토에 비해 높았다. 이상의 결과에서 무관수 옥상녹화시스템에 돌나물을 적용함에 있어, 토양배합비는 피트모스함량을 높인 인공배합토가 자연토보다는 바람하고 토심은 15cm가 토심 25cm보다 초장, 녹피율, 엽록소 함량 등 외형적인 생육상태가 양호하였다. 하지만, 토심 25cm에서는 생체중 및 건조중 등과 같이 현존량(Biomass)을 향상시킬 수 있어 조성목적에 따라 구분적용하는 것이 바람직하다. 이는 무관수 옥상녹화시스템에서 단기적인 녹피율을 높이고자 할 때 토심 15cm가 25cm보다 바람직하나, 장기적인 생육을 고려해볼 때, 토심 25cm가 15cm보다 유리함을 보여준다고 하겠다. 추후, 토양수분변화 및 각 옥상녹화시스템의 요소들과 생육요소들 간에 상관성 및 요인분석에 대한 분석이 좀 더 조사되어야 할 것으로 보인다.

This study proposes a guideline of a green roof system suitable for the local environment by verifying the growth of Zoysia japonica in a shallow, extensive, green roof system under rainfed condition. The experimental soil substrates into which excellent drought tolerance and creeping Z. japonica was planted were made with different soil thicknesses(15cm, 25cm) and soil mixing ratios(SL, P7P1L2, P6P2L2, P5P3L2, P4P4L2). The plant height, green coverage ratio, fresh weight, dry weight and chlorophyll contents of Z. japonica were investigated. For the soil thickness of 15cm, the plant height of Z. japonica was significantly as affected by the soil mixing ratio and it was shown in the order SL= P4P4L2 < P7P1L2 = P5P3L2 < P6P2L2. For the soil thickness of 25cm, the plant height was increased in order to SL < P7P1L2, P6P2L2, P5P3L2 < P4P4L2. The green coverage ratio was not observed by soil the mixing ratio or soil thickness. However, the green coverage ratio was 86∼90% with a good coverage rate overall. The chlorophyll contents of Z. japonica were not significantly affected by the soil mixing ratio in the soil thickness of 15cm, but were higher in the natural soil than in the artificial soil at 25cm soil thickness. The fresh weight and dry weight of Zoysia japonica were heavier in the 25cm thickness than in the 15cm thickness and in the artificial soil mixture than in the natural soil. The result indicated that the growth of Zoysia japonica was more effective in the 25cm soil thickness with artificial soil than in the 15cm soil thickness with natural soil in the green roof system under rainfed condition.