• 인간식물환경학회지
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• 제24권2호
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• pp.219-227
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• 2021

Background and objective: Urban street trees play an important role in carbon reduction in cities where greenspace is scarce. There are ongoing studies on carbon reduction by street trees. However, information on the carbon reduction capacity of street trees based on field surveys is still limited. This study aimed to quantify carbon uptake and storage by urban street trees and suggest a method to improve planting of trees in order to increase their carbon reduction capacity. Methods: The cities selected were Sejong, Chungju, and Jeonju among cities without research on carbon reduction, considering the regional distribution in Korea. In the cities, 155 sample sites were selected using systematic sampling to conduct a field survey on street environments and planting structures. The surveyed data included tree species, diameter at breast height (DBH), diameter at root collar (DRC), height, crown width, and vertical structures. The carbon uptake and storage per tree were calculated using the quantification models developed for the urban trees of each species. Results: The average carbon uptake and storage of street trees were approximately 7.2 ± 0.6 kg/tree/yr and 87.1 ± 10.2 kg/tree, respectively. The key factors determining carbon uptake and storage were tree size, vertical structure, the composition of tree species, and growth conditions. The annual total carbon uptake and storage were approximately 1,135.8 tons and 22,737.8 tons, respectively. The total carbon uptake was about the same amount as carbon emitted by 2,272 vehicles a year. Conclusion: This study has significance in providing the basic unit to quantify carbon uptake and storage of street trees based on field surveys. To improve the carbon reduction capacity of street trees, it is necessary to consider planning strategies such as securing and extending available grounds and spaces for high-density street trees with a multi-layered structure.

• Journal of Ecology and Environment
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• 제46권4호
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• pp.324-333
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• 2022

Background: The Korean scarlet dwarf, Nannophya koreana Bae (Odonata: Libellulidae), is anendangered dragonfly with an increasing risk of extinction owing to rapid climate changes and human activities. To prevent extinction, the N. koreana population and their habitat should be protected. Therefore, suitable habitat evaluation is important to build the N. koreana restoration project. The habitat suitability index model (HSI) has been widely used for habitat evaluation in diverse organisms. Results: To build a suitable HSI model for N. koreana, 16 factors were examined by seven experienced researchers. A field survey for N. koreana observed sites and spatial analysis were conducted to improve the model. Five factors were finally selected by this procedure (crown density, open water surface, water depth, pioneer plant cover, and type of water source). Finally, the N. koreana HSI model was generated with the five adjusted factors based on interview, field survey, and spatial analysis. This model was validated by a current N. koreana habitat in 2021. With this model, 46 sites in Uljin-gun, Korea, were surveyed for N. koreana habitats; five sites were identified as core habitats and seven as potential core habitats. Conclusions: This model will serve as a strong foundation for the N. koreana restoration project and as a reference for future studies on N. koreana and other endangered insect populations. Further analysis and long-term data will improve the efficacy of this model and restore endangered wildlife.

• 한국환경과학회지
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• 제31권6호
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• pp.479-490
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• 2022

This study was to evaluate the utilization of terrestrial light detection and ranging for forest inventory in coniferous forests. Heights and diameter of the stand trees were measured manually using the traditional measurement method and the method using terrestrial LiDAR. The results of two methods were compared and analyzed to evaluate accuracy and feasibility. The terrestrial LiDAR used fixed and handy types to compare the accuracy between different operational methods. Comparative analyses used a paired t-test and Bland-Altman plot analysis. In the case of tree heights, the average of difference between the traditional method and terrestrial LiDAR for each plot was 0.81 m, -0.07 m, and 0.13 m for fixed type; 2.88 m, 1.19 m, and 0.93 m for the handy type. In the case of tree diameter at breast height, the average value of the difference between traditional methods and terrestrial LiDAR for each plot was 0.13 cm, -0.66 cm, and -0.03 cm for fixed type; 2.36 cm, 2.13 cm, and 1.92 cm for the handy type. The values from the method using the fixed type was highly consistent with that using the traditional measurement methods; the average difference was closer to zero. The crown density influences the precision of the height measurement using terrestrial LiDAR in coniferous forests. Therefore, future studies should focus on verifying the accuracy of terrestrial LiDAR in forests and on expanding the utilization of terrestrial LiDARs according to their operational methods.

• 한국지형학회지
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• 제27권3호
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• pp.87-103
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• 2020

The purpose of this study is to evaluate the risk of cropland and man-made infrastructures in a landslide-prone area using a GIS-based method. To achieve this goal, a landslide inventory map was prepared based on aerial photograph analysis as well as field observations. A total of 550 landslides have been counted in the entire study area. For model analysis and validation, extracted landslides were randomly selected and divided into two groups. The landslide causative factors such as slope, aspect, curvature, topographic wetness index, elevation, forest type, forest crown density, geology, land-use, soil drainage, and soil texture were used in the analysis. Moreover, to identify the correlation between landslides and causative factors, pixels were divided into several classes and frequency ratio was also extracted. A landslide susceptibility map was constructed using a bayesian predictive model (BPM) based on the entire events. In the cross validation process, the landslide susceptibility map as well as observation data were plotted with a receiver operating characteristic (ROC) curve then the area under the curve (AUC) was calculated and tried to extract a success rate curve. The results showed that, the BPM produced 85.8% accuracy. We believed that the model was acceptable for the landslide susceptibility analysis of the study area. In addition, for risk assessment, monetary value (local) and vulnerability scale were added for each social thematic data layers, which were then converted into US dollar considering landslide occurrence time. Moreover, the total number of the study area pixels and predictive landslide affected pixels were considered for making a probability table. Matching with the affected number, 5,000 landslide pixels were assumed to run for final calculation. Based on the result, cropland showed the estimated total risk as US $ 35.4 million and man-made infrastructure risk amounted to US $ 39.3 million.

• 한국지형학회지
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• 제26권3호
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• pp.53-67
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• 2019

The purpose of this study is to identify the quality of landslide susceptibility in a landslide-prone area (Jinbu-myeon, Gangwon-do, South Korea) by spatial prediction modeling approach and compare the results obtained. For this goal, a landslide inventory map was prepared mainly based on past historical information and aerial photographs analysis (Daum Map, 2008), as well as some field observation. Altogether, 550 landslides were counted at the whole study area. Among them, 182 landslides are debris flow and each group of landslides was constructed in the inventory map separately. Then, the landslide inventory was randomly selected through Excel; 50% landslide was used for model analysis and the remaining 50% was used for validation purpose. Total 12 contributing factors, such as slope, aspect, curvature, topographic wetness index (TWI), elevation, forest type, forest timber diameter, forest crown density, geology, landuse, soil depth, and soil drainage were used in the analysis. Moreover, to find out the co-relation between landslide causative factors and incidents landslide, pixels were divided into several classes and frequency ratio for individual class was extracted. Eventually, six landslide susceptibility maps were constructed using the Bayesian Predictive Discriminant (BPD), Empirical Likelihood Ratio (ELR), and Linear Regression Method (LRM) models based on different category dada. Finally, in the cross validation process, landslide susceptibility map was plotted with a receiver operating characteristic (ROC) curve and calculated the area under the curve (AUC) and tried to extract success rate curve. The result showed that Bayesian, likelihood and linear models were of 85.52%, 85.23%, and 83.49% accuracy respectively for total data. Subsequently, in the category of debris flow landslide, results are little better compare with total data and its contained 86.33%, 85.53% and 84.17% accuracy. It means all three models were reasonable methods for landslide susceptibility analysis. The models have proved to produce reliable predictions for regional spatial planning or land-use planning.

• 한국지형학회지
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• 제27권2호
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• pp.65-80
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• 2020

This paper deals with risk assessment of life in a landslide-prone area by a GIS-based modeling method. Landslide susceptibility maps can provide a probability of landslide prone areas to mitigate or proper control this problems and to take any development plan and disaster management. A landslide inventory map of the study area was prepared based on past historical information and aerial photography analysis. A total of 550 landslides have been counted at the whole study area. The extracted landslides were randomly selected and divided into two different groups, 50% of the landslides were used for model calibration and the other were used for validation purpose. Eleven causative factors (continuous and thematic) such as slope, aspect, curvature, topographic wetness index, elevation, forest type, forest crown density, geology, land-use, soil drainage, and soil texture were used in hazard analysis. The correlation between landslides and these factors, pixels were divided into several classes and frequency ratio was also extracted. Eventually, a landslide susceptibility map was constructed using a logistic regression model based on entire events. Moreover, the landslide susceptibility map was plotted with a receiver operating characteristic (ROC) curve and calculated the area under the curve (AUC) and tried to extract a success rate curve. Based on the results, logistic regression produced an 85.18% accuracy, so we believed that the model was reliable and acceptable for the landslide susceptibility analysis on the study area. In addition, for risk assessment, vulnerability scale were added for social thematic data layer. The study area predictive landslide affected pixels 2,000 and 5,000 were also calculated for making a probability table. In final calculation, the 2,000 predictive landslide affected pixels were assumed to run. The total population causalities were estimated as 7.75 person that was relatively close to the actual number published in Korean Annual Disaster Report, 2006.

• 한국산림과학회지
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• 제107권1호
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• pp.1-15
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• 2018

신갈나무 천연림에서 솎아베기가 임내 미기후 환경과 버섯 발생에 미치는 영향을 알아보기 위하여 약 45%의 솎아베기 후 4년이 경과한 신갈나무림에 토양온도, 대기온도, 수관통과우량 및 토양수분량의 변화를 조사하였다. 그 결과 솎아베기를 인하여 수관울폐율이 4월부터 10월까지 약 6% 가량 낮아졌고 토양온도와 대기온도가 8월까지 $1{\sim}2^{\circ}C$ 이상 높아졌다가 9월 이후에는 차이가 점점 줄어들었다. 월별 평균 일교차는 10월까지 $0.2{\sim}0.7^{\circ}C$ 가량 커졌고 이후부터는 차이가 없었다. 또한 7월~9월 동안 수관통과우량이 약 135 mm 더 많아졌고 단위시간당 수관통과우량도 최대 3.5 mm/h 많아졌다. 강우시 토양 수분량은 약 5% 이상 더 많아졌고 강우 전 수준으로 되는 기간이 약 4일가량 더 걸렸다. 솎아베기 지역의 7~9월의 버섯 발생 종은 55종으로 균근성 버섯은 10종, 부후성 버섯은 1종이 더 증가하였고. Shanon-Wiener 지수는 3.2로 0.5가량 더 높았다. 솎아베기 지역에서는 제주쓴맛그물버섯(Tylopilus neofelleus) 등이 더 빨리 발생하였으나, 진갈색주름버섯(Agaricus subrutilescens), 깔때기버섯속(Clitocybe sp.)은 더 늦게 발생하였다. 또한, 제주쓴맛그물버섯(Tylopilus neofelleus)은 우점도가 약 6%, 발생량이 약 1.5배가량 증가하였고, 뽕나무버섯속(Amillaria sp.)은 우점도가 약 30%, 발생량이 약 20배 가까이 증가하였다. 이와 같은 결과로 신갈나무림에서 솎아베기는 버섯발생에 영향을 주는 토양과 대기의 온도, 수관통과우량과 토양수분을 증가시키며 이는 버섯 발생 종의 다양성 증가, 종별 발생시기의 변화, 일부 균근성버섯과 뽕나무버섯속(Amillaria sp.)의 우점도와 발생량을 증가시킨다고 결론짓는다.

• 한국환경생태학회지
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• 제24권2호
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• pp.157-165
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• 2010

본 연구는 일본 고베시 로코아일랜드 완충녹지의 공간기능별 지형구조, 식재개념, 식재구조를 조사분석하여 해안매립도시의 토지이용을 고려한 완충녹지 식재기법 연구 기초자료를 제공하고자 수행하였다. 로코아일랜드(총면적 580ha)는 대규모 완충녹지를 박스형으로 조성하여 외곽부의 항만물류 산업용지와 도시내부 도시기능용지로 구획되었다. 완충녹지 지형구조는 편향마운딩형, 병렬마운딩형, 복합마운딩형이었고, 북쪽의 녹지폭은 50m, 동쪽의 녹지폭은 8~32m, 서쪽의 녹지폭은 37.5m, 경사도는 $18\sim25^{\circ}$, 성토고는 2~15m이었다. 공간기능별 재개념은 해안측 사면부는 경관식재와 완충식재, 도시내부는 경관식재와 녹음식재를 적용하였다. 북측 완충녹지 식재구조 조사결과, 종가시나무, 녹나무, 후박나무, 녹보리똥나무 등 난온대 상록활엽수를 식재하였고, $100mm^2$단위의 종수 및 식재밀도는 최대 교목 9종 22주, 아교목 9종 15주, 관목 3종 67주로 전 층위 14종 104주이었다. 녹피율은 교목층 69~139%, 아교목층 26~38%, 관목층 6~7%, 전 층위 101~184%, 녹지용적계수는 교목층 $1.40\sim3.12m^3/m^2$, 아교목층 $0.43\sim0.55m^3/m^2$, 관목층 $0.06m^3/m^2$, 전 층위 $1.89\sim3.73m^3/m^2$이었다.

• 한국환경생태학회지
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• 제38권3호
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• pp.293-309
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• 2024

본 연구는 도서식물자원인 소사나무의 식물군집구조 분석을 통해 소사나무림의 서식지 외 보전 및 서식환경 등의 기초자료를 제공하고자 수행하였다. 군집구조 분석을 위하여 소사나무가 출현하는 안면도(중장리 산 14-217), 황금산, 가야산(원효봉), 팔봉산을 대상으로 총 27개의 방형구(각 100m²)를 설치 및 조사하였다. 군집분류는 TWINSPAN에 의한 classification 분석을 하였다. 군집분류 결과 소사나무-신갈나무 군락(I), 소사나무-소나무 군락(II), 소사나무-소나무 군락(III), 소사나무-신갈나무 군락(IV), 소사나무-굴참나무 군락(V), 소사나무-잔털벚나무 군락(VI), 소사나무-때죽나무 군락(VII) 등 총 7개의 군락으로 분류되었다. 종다양도는 0.8056~1.1568, 우점도는 0.1214~0.3024이며, 유사도지수는 9.37~36.36%이었다. 군락별 6개 환경인자를 RDA ordination로 상관관계 분석한 결과 제 1축을 기준으로 해발고도, 울폐도, 암석노출도, 경사도가 상관관계를 보였다. 군락 III(소사나무-소나무 군락)과 군락 IV(소사나무-신갈나무 군락)은 주로 해발고도, 암석노출도, 경사도가 식생분포에 영향을 미치는 환경인자로 나타났다. 군락 V(소사나무-굴참나무 군락), 군락 VI(소사나무-잔털벚나무 군락)와 군락 VII(소사나무-때죽나무 군락)은 울폐도가 식생분포에 영향을 미치는 환경인자로 나타났다.

• 한국산림과학회지
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• 제81권4호
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• pp.303-309
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• 1992

경기도(京畿道) 여주지역(驪州地域)의 사방시공(砂防施工) 후(後) 식물사회(植物社會)의 생태학적(生態學的) 변화에 대하여 검토하였다. 그 결과(結果)를 요약(要約)하면 다음과 같다. 1. 사방시공지(砂防施工地)(시공(施工) 후(後) 3년에서 14년까지)의 토양(土壤) 유기물층(有機物層) 증가(增加)는 $Y_{(cm)}=0.436X_{(yr)}-0.931$(r=0.978), 02 층(層)의증가(增加)는 $Y_{(cm)}=0.339_{(yr)}-0.931$(r=0.954)로 추정(推定)되었다. 2. 상층식생(上層植生)에 있어서 오리나무류(類)가 각 조사구에서 평균적(平均的)으로 상대피도(相對被度)는 32%, 상대밀도(相對密度)는 12.4%, 상대빈도(相對頻度)는 16.8%가 감소되었다. 이는 여주(驪州) 지역이 2-3년 사이에 오리나무 잎벌레의 피해 때문에 나타난 결과이다. 3. 상층식생(上層植生) 있어서 소나무류(類)의 상대빈도(相對頻度)는 사방(砂防) 시공(施工) 6, 7년 후(後)에 증가되고, 그리고 시공후(施工後) 10년에서 14년사이에는 40% 이상을 차지하는 우점종(優點種)의 수종(樹種)이 되었다. 4. 상층식생(上層植生)에 있어서, 사방시공(砂防施工) 당시 파종(播種)되거나 식재(植栽)되지 않은 참나무류(類)의 상대빈도(相對頻度)가 모든 조사지에서 증가 되었다. 5. 전(全) 수종(樹種)의 수관투영면적(樹冠投影面的) 증가(增加)는 $Y_{(m^2)}=18.020X_{(yr)}+18.834$ (r=0.954)로 추정(推定)된다. 6. 6(年) 후(後)의 Biomass는 14.88t/ha, 8년(年) 후(後)는 22.84t/ha, 10년(年) 후(後)는 35.08t/ha, 12년(年) 후(後)는 47.80t/ha, 14년(年) 후(後)는 58.13t/ha이다.