Wetland is transitional zone between land environment and water environment and is a distinctive ecosystem. It has been recognized of its value and is perceived as precious natural resource to have already become the subject of attention throughout the world.
Recently, studies of many karst wetlands have been increasing, because karst wetlands have been highly evaluated for their topographic distinctiveness and ecological value. However, studies of wetlands developing in karst regions are still rare in Korea. Although Gulbongsan doline wetland which is a type of karst wetlands has been recently reported, no study has been conducted on the factors for the formation of the wetland.
Therefore, in this study, based on doline wetlands located in Gomaru, Mitan-myeon, Pyeongchang-gun, Gangwon-do; Balgudeok, Nam-myeon, Jeongseon-gun, Gangwon-do; Sangyeryeong, Imgye-myeon, Jeongseon-gun, Gangwon-do; and Gulbongsan, Sanbuk-myeon, Mungyeong-si, Gyeongsangbuk-do, factors that affect the formation of wetlands were analyzed centering on topography, hydrology, and soil.
In addition, the effects of differences in flooding periods appearing in doline wetlands were analyzed. And the geographical characteristics of areas where doline wetland were studied. Through this study, the following conclusions were obtained.
Topography was shown to have the largest effects on the formation of doline wetlands. Since doline wetlands are formed by water supply from precipitation in a short period, larger catchment areas are more advantageous for the formation of wetland.
However, continuous supply of seeping water was shown to be important for wetlands once formed to be maintained. The supply of underground water is affected by the distance between the seepage point and the wetland. Even though this distance is long, wetlands can be maintained for a long time if artificial reservoirs that play the role of temporarily storing underground water exist.
Since doline wetlands exist in both areas where soil drainage is smooth and poor, the formation of wetlands was shown to be not much related with drainage abilities of soil.
Flooding periods of doline wetlands are affected by underground water supplied from seepage points. The supply of underground water affects wetland soil''s geochemical characteristics such as pH and CEC. When seen from the viewpoint of material circulation, areas in which the supply of underground water is not smooth correspond to storage areas and those in which the supply of underground water is continuous correspond to source areas.
Dolines and doline wetlands show geographical differences in their distributions. Doline wetlands are mainly developed on dolines at the mountaintops and slopes rather than those on the river terraces.