Journal of Korean Society for People, Plants and Environment 2011;14(6):379-391.
Published online December 30, 2011.

자연습지 식생구조를 고려한 국립수목원 수생식물원의 생태 설계 제안

조동길(Dong Gil Cho), 진혜영(Hye Young Jin), 송정화(Jeong Hwa Song)

Abstract

Both man-made wetlands and natural wetlands perform various functions such as promoting biodiversity and reducing floods. For newly created or restored wetlands to function similar to natural wetlands, above all, they need to be configured similar to natural wetlands. To this end, a survey and analysis on control wetlands and, based on which, an approach on ecological plantation design are essential. In this context, in order to select plants for an aquatic garden in Korea National Arboretum, this study reviewed plants inhabiting in the local area, plants observed in control wetlands, and plants recorded in various literatures. Then, based on the outcome, it was aimed to allocate plants appropriately in consideration of the types of wetlands in the newly created aquatic garden. First, in order to understand the types of control wetlands, a total of 11 sites, including 6 fringe -type, 4 depressional-type and 1 slope-type wetlands, were selected to survey vegetation and soil. Hydrophytes observed in 11 control wetlands include 50 species in fringe wetlands, 18 species in slope wetlands and 16 species in depressional wetlands. Meanwhile, analysis on relations between hydrophytes and environment conditions such as water depth showed no significant difference from earlier studies. However, no clear distribution patterns concerning water depth were defined. Findings from soil analysis were also not greatly different from earlier results. In the end, it was concluded that mild acid to neutral soil in a range of pH 5.6~6.8 with electric conductivity less than 0.2ms/100g and cation exchange capacity of 20me/100g was recommended. Plants for the aquatic garden were selected by taking into account various literatures, surveys of control wetlands, and species found in current aquatic gardens. Hydrophytes selected for the aquatic garden include 21 species for mountain wetlands, 20 species for riverine wetlands and 63 species for palustrine wetlands. Meanwhile, selected plants were allocated by wetland type in consideration of locational features within the aquatic garden and category features. In particular, water depth was carefully considered as it is highly related to the growth and distribution of hydrophytes. Emergent plants and floating-leaved plants were placed to grow in water depth of less than 50cm and between 30~60cm, respectively. In the case of floating-leaved plants, areas where water depth is highly volatile were avoided to prevent leaves from touching the bottom of wetlands during a drought period. Submerged plants are not greatly affected by the depth of water, but they were selected for all areas with water depth of 50~150cm. In particular, submerged plants with strong water purification ability were selected. Floating plants do not require a certain water depth, but they were planted in an area where water level fluctuates to prevent them from touching the bottom of wetlands during a drought period.

KeyWords: Aquatic garden, Ecological design, Natural wetlands, Plantation design, Reference wetlands