Effect of Wind Break on the Early Growth of Pinus thunbergii at Saemangum Sea-wall

Department of Forest Science, Sangji University(Received August 30, 2013; Revised October 1, 2013; Accepted November 10, 2013)ABSTARCTThe sea breeze shows different characteristics compared to land breeze, such as high wind speed andmore rapider shift period. One of the major factors affecting plant early growth is wind speed. In theearly growth stage, tree growth-rates rise with decreasing wind speed. Thus, the study was performedto identify wind break effects on wind characteristics and tree growth. The wind break used in thisstudy was about 130 meters length and 3 meters height, made up with poly-ethylene (with 40%openness). We installed one vane and fifteen anemographs at three different heights (1, 2 and 3meters) on the inner and outer wind break areas. The wind characteristic and plant growth data werecollected from Jun. 2011 to Oct. over 2012. The wind rose of the Saemangum seawall area presentedthe north (21.5%) and it was followed by north-west (18.1%), east (14.9%) and north-east (13.7%)and the remainder with other directions. Wind speeds at height were different. The tree height was159.6 cm at inside and 129.6 cm at outside. The diameter at root-collar was 36.9 mm at inside and32.6 mm at outside from wind break. Key words: Sea breeze, Wind rose, Wind speed decrease, Pinus thunbergii