• The Korean Journal of Ecology
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• v.25 no.5
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• pp.321-328
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• 2002

In order to provide the basic information for restoration of vegetation, conservation of rare species and maintenance of biodiversity, changes of site factors and vegetation by human trampling disturbance were investigated at the subalpine zone near the peak of Mt. Sorak in Korea. The destructed vegetation was found mainly in the southern parts with gentle slope in this study area. Height and coverage of vegetation and the species diversity decreased, and the community structure depended on trampling strength. Soil moisture, organic matter contents and litter thickness in the site with destructed vegetation by human trampling showed lower values than in the undisturbed site. Soil depth decreased, and gravel exposure on the ground surface increased by soil erosion responded to trampling strength.

• The Korean Journal of Ecology
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• v.4 no.1_2
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• pp.33-37
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• 1981

This study was carried out to investigate the changes of flower properties due to decomposition in the course of time and results obtained are as follows; 1. The flower shape of Salix babylonica changed so rapid that it was difficult to recognize fragments after 40 days. 2. Total weight decreased by 50% after about 40 days. Loss on ignition changed rapidly for 40 days and then steadily. 3. Remaining carbon content decreased by a half only for first 20 days, then did steadily. 4. The content of phosphorus and total nitrogen slowly during the early period and then rapidly. 5. Above phenomena are supposed to be responisble for water content, nitrogen, and phosphorus.

• Korean Journal of Ecology and Environment
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• v.46 no.1
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• pp.18-24
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• 2013

The objective of study was to protect seabird breeding site and vegetation restoration of Chilbal and Sokugul island in Shinan county Jeonnam province, April and December 2011. We analyzed the soil properties according to the dominant communities and environmental gradient. As a result, It was highly analyzed to moisture content, organic matter, salinity, total nitrogen in Commelina communis community and low analyzed in Achyranthes japonica community. Carex boottiana community which mainly used as a seabird habitat has a wide range and Achyranthes japonica and Artemisia princeps community was narrowed to soil properties. Soil pH of Carex boottiana community in Sogugul island was the lowest on 3.14 and Peucedanum japonicum community was the highest. Soil moisture content and organic matter was analyzed by the high value in Peucedanum japonicum community. In contrast, Achyranthes japonica was the low value and Carex boottiana community was analyzed the highest on the salinity and total nitrogen. On the soil environmental characteristics according to the environmental gradient, The higher altitude, moisture content, organic matter, salinity and total nitrogen was the lower in Chilbal island. In the case of Sokugul island, the altitude difference did not show the characteristics of soil environmental factors for small area and low altitude. But moisture content is similar to soil property of Chilbal island. Soil property was strongly acid soil because of seabird dropping. This results will be helpful to manage the invasive plants.

• Korean Journal of Environment and Ecology
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• v.20 no.4
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• pp.425-435
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• 2006

The objectives of this research were to investigate the drought resistance as well as the growth of Wisteria floribunda seedlings with the soil water conditions. The seedlings for the research were grown in pots with strict water content control on a frame located outdoors. During the experiments, the soil water contents were adjusted to 5, 10, 20, 30, 40, 50, 60, and 70%. In addition, the effects of Rhizobium inoculation on the growth of seedlings were investigated. The experimental results are summarized as follows: 1. The seedlings in the pots with 5% soil water content withered to death due to the water stress. Withering or any distinct growth was not observed from the seedlings in the 10% soil water content. It can be inferred from these results that about 5% of soil water content is the wilting point of W. floribunda seedlings and about 10% is the critical soil water content of its growth in this experiment soils. Therefore, it seems that W. floribunda possesses a good drought resistance. 2. From the analyses of the main growth parameters such as stem elongation, diameter growth, leaf area growth and total dry weight, it was found that the seedling growth can be improved with increasing soil water contents. The relation between each growth parameter(Y) and the soil water contents(W) was well described by a quadratic equation, $Y=a+bW+cW^2$. 3. In soil water contents higher than 20%, the seedling growth(Y) was remarkable along with-its extended growing period, and related to the growing period(D) by a quadratic equation, $Y=a+bD+cD^2$. 4. The artificial inoculation of Rhizobiun promoted the growth of Wisteria floribunda seedlings. 5. Rhizobium was found to be more readily inoculated and to form more root nodules compared to seedlings grown in higher soil water contents.

• Korean Journal of Environment and Ecology
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• v.26 no.4
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• pp.588-592
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• 2012

To examine the reason of empty samara production of Chinese elm, Ulmus parviflora, twenty two planted trees in Wonju-si were monitered for three years in terms of their flowering, pollinatiom system and samara characteristics. Inflorescences with bisexual flowers of Chinese elm are developed in the leaf axils on the twigs. Dichogamous flowers are varied with protogynuous and protandrous flower, and stamens in some bisexual flowers are developed in seperated time on a inflorescence or a tree. It is revealed newly that the flower of Chinese elm is out-crossed and partially insect(Apis mellifera) pollinated. The ratios of sound samara are significantly differed among years, the heighest values 65.5% were shown in 2009, lowered 42.9% in 2010, and the lowest 37.5% in 2011. This result might be affected by mean daily precipitation and number of rainy days during the flowering date, and lower temperature during the floral initiation stage, especially in 2011. These findings suggest that Chinese elm has self-incompatibility strategy and much pollination failure resulted in a production of much empty samaras. Further researches on the empty-seed production strategies and pollination system of major tree species might be needed.

• Korean Journal of Agricultural and Forest Meteorology
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• v.9 no.2
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• pp.121-131
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• 2007

Despite the close linkage in changes between the ecological and hydrological processes in forest ecosystems, an integrative approach has not been incorporated successfully. In this study, based on the vegetation and hydrologic data of the Gwangneung headwater catchment with the Geographic Information System, we attempted such an integrated approach by employing the Regional Hydro-Ecologic Simulation System (RHESSys). To accomplish this, we have (1) constructed the input data for RHESSys, (2) developed an integrated calibration system that enables to consider both ecological and hydrological processes simultaneously, and (3) performed sensitivity analysis to estimate the optimum parameters. Our sensitivity analyses on six soil parameters that affect streamflow patterns and peak flow show that the decay parameter of horizontal saturated hydraulic conductivity $(s_1)$ and porosity decay by depth (PD) had the highest sensitivity. The optimization of these two parameters to estimate the optimum streamflow variation resulted in a prediction accuracy of 0.75 in terms of Nash-Sutcliffe efficiency (NSec). These results provide an important basis for future evaluation and mapping of the watershed-scale soil moisture and evapotranspiration in forest ecosystems of Korea.

• Journal of Korean Society of Forest Science
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• v.87 no.1
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• pp.90-97
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• 1998

This study was carried out to compare the characteristics of relative conductivity(RC) in the twenty-one deciduous broad-leaved species. The results obtained were summarized as follows : 1. The RC ranged from $3.18{\times}10^{-15}$ to $1.23{\times}10^{-10}m^2$ in deciduous broad-leaved species, and appeared different values in various portions of a tree and species. 2. In eight diffuse-porous species, the ranges of average RC were $3.49{\times}10^{-13}$ to $6.35{\times}10^{-11}m^2$ in stems. $4.89{\times}10^{-13}$ to $2.99{\times}10^{-11}m^2$ in branches, and $1.33{\times}10^{-13}$ to $9.42{\times}10^{-12}m^2$ in junction part between stem and branch. In thirteen ring-porous species, the RCs were $7.14{\times}10^{-13}$ to $4.76{\times}10^{-11}m^2$ in stems, $2.93{\times}10^{-13}$ to $3.91{\times}10^{-11}m^2$ in branches, and $1.14{\times}10^{-13}$ to $9.20{\times}10^{-12}m^2$ in junction part. 3. The RC and diameter of stem have no interrelation in eight diffuse-porous species. The RC of stem increased with decreasing diameter of stem in eleven ring-porous species except Fraxinus mandshurica and Maackia amurensis. 4. In five deciduous broad-leaved species, the RC of 1-year-old shoots(the leader and adjacent laterals ) ranged from $4.87{\times}10^{-13}$ to $8.41{\times}10^{-11}m^2$ in the leaders, and $7.93{\times}10^{-14}$ to $2.01{\times}10^{-11}m^2$ in the adjacent laterals. The RCs were much greater in the leaders than in the adjacent laterals because of the hydraulic dominance of the leader shoot.

• Korean Journal of Remote Sensing
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• v.33 no.6_1
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• pp.993-1001
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• 2017

Drought is a worldwide natural disaster with extensively adverse impacts on natural ecosystems, agricultural products, social communities and regional economy. Various global satellite observations, including SMAP soil moisture, GRACE terrestrial water storage, Terra and Aqua vegetation productivity, evapotranspiration, and satellite precipitation measures are currently used to characterize seasonal timing and inter-annual variations of regional water supply pattern, vegetation growth, drought events, and its associated influence ecosystems and human society. We suggest the satellite monitoring system development to quantify meteorological, eco-hydrological, and socio-ecological factors related to drought events, and characterize spatial and temporal drought patterns in Korea. The combination of these complementary remote sensing observations(visible to microwave bands) provide an effective means for evaluating regional variations in the timing, frequency, and duration of drought, and availability of water supply influencing vegetation and crop growth. This integrated drought monitoring could help national capacity to deal with natural disasters.

• Proceedings of the Korea Water Resources Association Conference
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• 2015.05a
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• pp.274-274
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• 2015

전 세계적으로 식량과 물 안보에 대한 중요도가 높아지고 있으며 이에 따라 물발자국은 식량과 물을 연계하는 요소로서 거론되고 있다. 물발자국은 제품이 생산되는 과정동안에 사용되는 물의 양을 의미하며 $m^3/ton$으로 표현한다. 이러한 물발자국은 작물 필요수량 및 생산량을 기반으로 산정되기 때문에 기후변화와 밀접한 관계가 있다. 따라서 농업 및 수자원 계획 분야에서 물발자국의 활용성을 높이기 위해서는 기후변화에 따른 우리나라 농산물의 물발자국 변화를 살펴보는 것이 필요하다. 이에 따라 본 연구에서는 기후변화에 따른 논벼의 농업용수량 및 생산량 산정을 통하여 미래의 녹색 및 청색 물발자국을 산정하고, 시기 및 시나리오별 불확실성 및 민감도를 평가하고자 하였다. 기후변화 시나리오는 RCP 기반의 신 기후변화 시나리오를 이용하였으며, 물발자국 산정 작물은 우리나라의 주곡인 논벼를 대상으로 하였다. 물발자국은 작물의 단위생산량당 소비되는 물의 양으로 정의되며, 최근 연구에서 물발자국은 용수 공급원에 따라 녹색(green), 청색(blue), 회색(grey) 물발자국으로 구분하여 산정되고 있다. 본 연구에서는 작물의 증발산으로 소비되는 수량만을 물발자국 산정에 적용하여 증발산량 중 강우에 의해 공급되는 수량인 녹색 물발자국과 관개에 의해 인위적으로 공급되는 수량인 청색물발자국을 산정하였다. 기후변화에 따른 미래의 작물의 생산량을 산정하기 위해 작물모델로 기상, 재배관리, 작물의 유전정보, 토양수분 및 질소의 효과까지 고려하여 작물의 생육뿐만 아니라 생산량까지도 모의할 수 있는 CERES-Rice모델을 적용하였다. 미래 기후 전망을 위한 전지구모형은 종류가 다양하고 모형의 특성과 모형 입력 자료에 따라 모의 결과가 상이하게 나타남에 따라 불확실성을 내포하고 있다. 따라서 기후변화에 능동적으로 대처할 수 있는 논벼의 물발자국을 산정하기 위하여 각 시나리오 및 시기별 물발자국의 불확실성 및 민감도를 분석하였다. 본 연구의 결과는 기후변화에 따른 미래 농업수자원의 변화를 분석하는데 이용될 수 있을 뿐 만아니라 우리나라 미래 국가수자원 정책의 수립을 위한 기초자료로 활용될 것으로 기대된다.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.23 no.6
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• pp.29-41
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• 2020

Wild pollinators provide important pollination services for crops. However, their geographical ranges and impact on pollination services have not been fully explored within the scope of Korean agricultural land. This study aims to identify spatial supply-demand mismatches across orchard fields in the context of assessing pollination service risk. We first used National Ecosystem Survey data and a species distribution model (MaxEnt) to develop the geographic range of each of 32 wild pollinators belonging to three families (Diptera, Hymenoptera, and Lepidoptera). We then summed the modeled presence probability of each species to obtain a measure of spatially explicit pollinator richness. This modeled richness, defined as pollination supply, was compared with the summed area of orchard fields at the municipal boundary level to identify areas with supply-demand mismatches. The study found that Lepidoptera showed the highest species richness (8.3±1.5), followed by Hymenoptera (4.3±0.8) and Diptera (3.5±0.8) species. Median orchard area was 1.5 ㎢ (range of 0-176.7 ㎢) among 250 municipal regions in South Korea. The municipal regions were divided into three categories (tertiles) of low, middle, and high pollination supply and demand according to, respectivley, average polliator richness and orhard area. Finally, we found that 55 municipal regions (accounting for 49% of national orchard land) potentially faced high risk of pollination deficits, 81 regions (48% of national orchard land) faced intermediate risk, and 63 regions faced low risk (3% of national orchard land). In conclusion, this study revealed significant mismatch between pollination supply and demand and developed risk assessment map will guide our future efforts on pollinator habitat conservation and monitoring to conserve crop pollination services.