• 한국환경복원기술학회지
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• 제10권1호
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• pp.44-56
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• 2007

The flora was summarized as 195 taxa; 73 families, 138 genera, 168 species, 23 varieties and 4 forms in Jangsoo-ri windbreak forest and 151 taxa; 63 families, 118 genera, 131 species, 18 varieties and 2 forms in Pyeongsa-ri windbreak forest. Based on the list of the rare plants by the Forest Research Institute, 3 taxa and based on the list of Korean endemic plant 4 taxa were recorded in the studied areas; Puccinellia coreensis (Gramineae), Asarum maculatum (Aristolochiaceae), Prunus yedoensis (Rosaceae), Koelreuteria paniculata (Sapindaceae), Adenophora triphylla var. hirsuta (Campanulaceae). The Specific Plant Species which is categorized by the Ministry of Environment, Korea, was summarized as 23 taxa for the 1 degree of 17 taxa, 3 degree of 5 taxa, 5 degree of 1 taxa in Jangsoo-ri windbreak forest and 22 taxa for the 1 degree of 18 taxa, 3 degree of 3 taxa, 5 degree of 1 taxa in Pyeongsa-ri windbreak forest. From the enlisted the flora surveyed, the naturalized plants were 17 taxa in Jangsoo-ri windbreak forest and 19 taxa in Pyeongsa-ri windbreak forests with the Naturalization rate was 8.7 percent and 12.6 percent, respectively. In Jangsoo-ri windbreak forest, there has been occurred many man-made impair and development without legal institution and control. So, it needs in haste institutional conservation measures and systemic database construction about function and necessity of windbreak forest. In Pyeongsa-ri windbreak forest, recently many people visited here. So, if we make eco-tour place connecting nearby coast and windbreak forest, it will contribute resident's economic profit and opportunity, concerns about windbreak forest, and necessity of conservation measures. Recently, the windbreak forests in Jangsoo-ri and Pyeongsa-ri should be bereaved windbreak forest of function by the human activities.

• 한국분무공학회지
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• 제19권3호
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• pp.136-141
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• 2014

This study reports numerically the characteristics of dust scattering around the coal storage pile yards, substantially affected by the windbreak wall height. The dust scattering is closely associated with the frictional effect of wind flows as well as the pressure variation that consequently affect the dust particle behavior. In the present study, with the use of the commercial code of FLUENT, the distribution of wind velocity and pressure are predicted around coal storage pile yard for four different heights of the wind break wall. From the results, it was found that for the case 1 with the outer windbreak wall height of 3 m and inner windbreak wall height of 6 m, the amount of scattering dust for a year was estimated to be 1451 kg, whereas for the case 4 where a height of outer windbreak wall is 10 m and a height of inner windbreak wall is 16 m, the amount of scattering dust for a year was 358 kg. It shows that the dust scattering can be reduced by 75%, indicating important role of windbreak wall height on particle scattering. The numerical results would be useful in decision of the appropriate height of windbreak wall for decreasing the amount of scattering dust under various environmental conditions.

• 한국공간구조학회논문집
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• 제14권2호
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• pp.51-58
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• 2014

Meteorological observatories use measuring boards on even ground in open areas to measure the amount of snowfall. However, it is very difficult to evaluate the accurate amount of snowfall because of the effects of the wind. Therefore, this study tried to determine the internal wind flow inside a windbreak fence to identify an area that was not affected by wind in order to measure the snowfall. We performed a computational fluid dynamics analysis, wind tunnel test of the type and height of the windbreak fence, and analyzed the wind flow inside the fence. The results showed that a double windbreak fence was better than a single windbreak fence for reducing the wind velocity. The reduction of the wind velocity was highest in the middle of a windbreak fence with a width of 4 m and a height of 60cm, where the windbreak fences were fixed to the ground.

• Journal of Forest and Environmental Science
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• 제33권4호
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• pp.348-354
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• 2017

Agroforestry has been practiced in arid and semi-arid regions for the purposes of preventing desertification and to increase income for locals. However, the intended effects of such practices have been limited due to strong winds and aridity. This study undertook multi-year monitoring of the productivity of income crops associated with windbreak planting in a semi-arid region of Mongolia, and explored strategies of windbreak planning to enhance the multi-purpose effects of agroforestry practices. The tree crown density of windbreak planting was on average 40% in one year after planting and 65% 2-3 years after, and thereby windspeeds were reduced by about 30% and 54%, respectively. Average windspeed reductions at leeward distances from the windbreak planting were approximately 60% within 3H (H=tree height), 50% at 5H, and 42% at 7-9H, presenting a pattern in which the farther the distance the less the reduction in windspeeds. The windbreak planting increased crop productivity by up to 6.8 times, compared to the productivity absent of windbreaks. Increases in the crown density as stated above resulted in increases of crop productivity by up to 3.6 times. Based on such results, this study proposed a model of windbreak planning as a typical land-use system of border windbreak planting or alternate windbreak planting of combining trees and income crops. The model also included tree planting with a crown density of 60% and allocation of income crops within a leeward distance of 5 times the height of the trees to reduce windspeeds by about 50%. The results from this study are applicable to practicing agroforestry not only at the study site but also in other regions worldwide where strong winds and aridity are problematic.

• Wind and Structures
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• 제35권5호
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• pp.309-322
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• 2022

Due to the complex terrain around high-speed railways, the windbreaks were established along different landforms, resulting in irregular windbreak transition regions between different subgrade infrastructures (flat ground, cutting, embankment, etc). In this paper, the effect of a windbreak transition on the wind flow around railways subjected to crosswinds was studied. Wind tunnel testing was conducted to study the wind speed change around a windbreak transition on flat ground with a uniform wind speed inflow, and the collected data were used to validate a numerical simulation based on a detached eddy simulation method. The validated numerical method was then used to investigate the effect of the windbreak transition from the flat ground to cutting (the "cutting" is a railway subgrade type formed by digging down from the original ground) for three different wind incidence angles of 90°, 75°, and 105°. The deterioration mechanism of the flow fields and the reasons behind the occurrence of the peak wind velocities were explained in detail. The results showed that for the windbreak transition on flat ground, the impact was small. For the transition from the flat ground to the cutting, the influence was relatively large. The significant increase in the wind speeds was due to the right-angle structure of the windbreak transition, which resulted in sudden changes of the wind velocity as well as the direction. In addition, the height mismatch in the transition region worsened the protective effect of a typical windbreak.

• 한국자원식물학회지
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• 제21권1호
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• pp.5-11
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• 2008

본 조사는 2005년 12월부터 2007년 4월까지 총 4회에 걸처 전라남도 진도군 조도면 관매도 해안 방풍림을 지역을 중심으로 곰솔군락의 특성을 조사하고 생태학적인 관리방안을 제시하였다. 관매도 해안 방풍림인 곰솔군락을 주요 구성종과 식생유형에 따라 교란형, 성장형, 혼합형, 안정형, 배후산지형 식생 등으로 구분하였다. 교란형 식생과 성장형 식생의 곰솔군락에서는 간벌, 풀베기, 솔아내기, 휴식공간 활용, 병든 소나무 벌목 등을 통하여 적극적인 관리가 필요한 실정이며, 혼합형 식생, 안정형 식생 그리고 배후산지형의 곰솔군락에서는 방풍림 산책로, 삼림완충지대 조성, 식생천이를 유도함으로서 자연식생을 복원할 수 있는 적극적인 해안 방풍림 보전이 필요하다. 조사지역에서는 해안 방풍림의 서식지 특성과 분포실태에 따라 해수욕장과 공한지 주변지역 관리, 배후습지 복원 관리, 외래식물 분포 억제 관리, 생물종의 다양성과 서식지의 다양성 유지 관리, 곰솔림의 고령화와 병충해 확산 예방 관리 등 생태학적인 관리방안이 요구된다.

• 한국환경복원기술학회지
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• 제14권1호
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• pp.89-104
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• 2011

This study was carried out to the development of ecological planting model to make up of coastal windbreak forest on the Suncheon-bay in Sucheon-si, Korea. Make up of coastal windbreak forest in this site was needed for appropriate bioresource, biodiversity and ecological structure, and for conservation of the eco-tour resource and protection of human life and property by the unforeseen disaster from the coast. Based on the plant-social principle, the planting model of windbreak forest was developed to facilitate growth of trees, considering planting locations. The ecological planting model for the coastal windbreak was composed of warm temperate evergreen and windbreak forest which is spreading around the inland area in Korea. The horizontal forest style was composed of forest edge community and inner forest community, and the vertical forest style was composed of upper, middle, low and ground planting class. The target of the present model was quasi-natural forest, and the species of tree were selected based on the adaptability to surroundings depending on a goal to create a forest and forest style. To achieve both functions of wind break forest and visual effect in short period of time, small trees and seedlings were planted with high-density of 40,000/ha in an expectation of easy natural maintenance in the future. The significance of the present study is a suggestion for a guideline to create ecological coastal windbreak forest in the Suncheon-bay in which the harmony of human life and the ecological conservation is of great importance. Also, the ecological coastal windbreak forest model should be developed further through the long term monitoring after construction of forest.

• 한국환경생태학회지
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• 제19권3호
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• pp.246-257
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• 2005

본 조사 지 역의 식물상은물건리 방풍림에서 66과 135속 147종 25변종4품종총 176분류군이, 미조리 방풍림에서는63과 123속 138종 13변종2품종 총 153분류군이 확인되었다. 이중환경부지정 식물구계학적 특정식물종을살펴보면, 물건리 방풍림에서 I 등급은 말오줌때,푸조나무, 천선과나무 등24분류군, n등급은 갯걱이삭, 검양옻나무, 모감 주나무 3분류군 등 총 27분류군으로 분석되었으며, 미조리 방풍림에서는 I 등급이 구실잣밤나무,장딸기,보리밥나무등28분류군,르등급에는 생달나무,감탕나무,육박나무 등7분류군등총35분류군이 확인되었다. 또한 귀화식물에는 물건리 방풍림에서 17분류군, 미조리 방풍림에서 9분류군이 조사되었으며, 귀화율은 각각$9.7\%,5.9\%$로 분석되었다.

• Journal of Ecology and Environment
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• 제37권2호
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• pp.91-97
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• 2014

Little is known about how the increased porosity of a deciduous windbreak, which results from loss of leaves, influences wind speed reduction. We hypothesized that, with loss of foliage, the wind speed reduction effectiveness of a deciduous windbreak decreases on near leeward side but not on further leeward side and that wind speed recovers faster in the full foliage season than in other seasons. During summer, autumn, and winter (full, medium, and non-foliage season, respectively), we observed wind speed and direction around a deciduous windbreak in a traditional Korean village on windward and near and further leeward sides (at -8H, 2H, and 6H; H = 20 m, a windbreak height). We used a linear mixed effects model to determine that the relative wind speed reduction at 2H significantly decreased from 83% to 48% ($F_{2,111.97}=73.6$, P < 0.0001) with the loss of foliage. However, the relative wind speed reduction at 6H significantly increased from 26% to 43% ($F_{2,98.54}=18.5$, P < 0.0001). Consequently, wind speed recovery rate between 2H and 6H in summer was two times higher than in autumn and ten times higher than in winter ($F_{2,102.93}=223.1$, P < 0.0001). These results indicate that deciduous windbreaks with full foliage seem to induce large turbulence and increase wind speed recovery rate on leeward side. Our study suggests that further research is needed to find the optimal foliage density of a deciduous windbreak for maximizing windbreak effectiveness regardless of seasonal foliage changes.

• 한국환경복원기술학회지
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• 제15권6호
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• pp.29-41
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• 2012

This study was conducted in Ningxia Hui autonomous region, located at southern part of Mu Us sand land in China. To investigate relationships between windbreak effect and installation cost of sand barriers, plastic net is utilized by using four kind of heights (0.2, 0.3, 0.4 and 0.5m) and four kind of porosities (20, 30, 50 and 70%). These heights and porosities are measured for estimating distances for effective windbreak. It is shown that porosity and the distance have a positive relationship at same heights and porosity on ground indicates a constant figure when height reaches a certain level, regardless of the porosity. This implies that there is a difference of level of windbreak with different porosities; however, distance of windbreak effect is same at the same height of sand barrier. As a result of comparison between porosity of sand barrier on the ground and installation cost in each sand barrier with various heights and porosities (16 combinations), 0.4m and 0.5m height sand barriers describe highest economical efficiency. Within two variables, we concluded that height has a higher impact on windbreak effect than porosity.