• Title/Summary/Keyword: Forest-fire

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A simple estimate of the carbon budget for burned and unburned Pinus densiflora forests at Samcheok-si, South Korea

  • Lim, Seok-Hwa;Joo, Seung Jin;Yang, Keum-Chul
    • Journal of Ecology and Environment
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    • v.38 no.3
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    • pp.281-291
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    • 2015
  • To clarify the effects of forest fire on the carbon budget of a forest ecosystem, this study compared the seasonal variation of soil respiration, net primary production and net ecosystem production (NEP) over the year in unburned and burned Pinus densiflora forest areas. The annual net carbon storage (i.e., NPP) was $5.75t\;C\;ha^{-1}$ in the unburned site and $2.14t\;C\;ha^{-1}$ in the burned site in 2012. The temperature sensitivity of soil respiration (i.e., $Q_{10}$ value) was higher in the unburned site than in the burned site. The annual soil respiration rate was estimated by the exponential regression equation with the soil temperatures continuously measured at the soil depth of 10 cm. The estimated annual soil respiration and heterotrophic respiration (HR) rates were 8.66 and $4.50t\;C\;ha^{-1}yr^{-1}$ in the unburned site and 4.08 and $2.12t\;C\;ha^{-1}yr^{-1}$ in the burned site, respectively. The estimated annual NEP in the unburned and burned forest areas was found to be 1.25 and $0.02t\;C\;ha^{-1}yr^{-1}$, respectively. Our results indicate that the differences of carbon budget and cycling between both study sites are considerably correlated with the losses of living plant biomass, insufficient nutrients and low organic materials in the forest soil due to severe damages caused by the forest fire. The burned Pinus densiflora forest area requires at least 50 years to attain the natural conditions of the forest ecosystem prior to the forest fire.

Predicting Forest Fires Using Machine Learning Considering Human Factors (인적요인을 고려한 머신러닝 활용 산림화재 예측)

  • Jin-Myeong Jang;Joo-Chan Kim;Hwa-Joong Kim;Kwang-Tae Kim
    • Journal of Korea Society of Industrial Information Systems
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    • v.28 no.5
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    • pp.109-126
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    • 2023
  • Early detection of forest fires is essential in preventing large-scale forest fires. Predicting forest fires serves as a vital early detection method, leading to various related studies. However, many previous studies focused solely on climate and geographic factors, overlooking human factors, which significantly contribute to forest fires. This study aims to develop forest fire prediction models that take into account human, weather and geographical factors. This study conducted a comparative analysis of four machine learning models alongside the logistic regression model, using forest fire data from Gangwon-do spanning 2003 to 2020. The results indicate that XG Boost models performed the best (AUC=0.925), closely followed by Random Forest (AUC=0.920), both of which are machine learning techniques. Lastly, the study analyzed the relative importance of various factors through permutation feature importance analysis to derive operational insights. While meteorological factors showed a greater impact compared to human factors, various human factors were also found to be significant.

The Effect of Forest Fire on the Raptor Habitation (대형 산불이 맹금류 서식에 미치는 영향)

  • Ran Sung-Woo;Lee Joon-Woo;Paek Woon-Kee;Lee Han-Soo;Kim In-Kyn;Hong Gil-Pyo;Kang Jung-Roon;Paek In-Rwan
    • Korean Journal of Environment and Ecology
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    • v.19 no.4
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    • pp.385-392
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    • 2005
  • This study was conducted in order to analysis the forest fire effect to the raptors habitating in and around the large forest fire occurred area, Goseong country, Gangwon province, Korea. There were observed raptor birds belonging to 8 species, 3 families, and 2 orders in the survey area. The most dominant species was Eurasian Hobby(Falco subbuteo), which was followed by Common Buzzard(Buteo buteo), Kestrel(Faico tinnunculus) and Chinese Sparrow Hawk(Accipiter soloensis). The largest number of species and individuals were observed in May 2002. In partially undamaged areas and undamaged areas, five species of rapacious birds were observed, which was the largest number of species observed. If an environment where rapacious birds can build nests is created in forest fire damaged area in order to raise the number of species and population, the number of species and population of rapacious birds living in the forest fire damaged area will grow further.

Differences in Breeding Bird Communities by Post-fire Restoration Methods (산불 후 복원방법의 차이가 번식기 조류 군집에 미치는 영향)

  • Kim, Jin-Yong;Lee, Eun-Jae;Choi, Chang-Yong;Lee, Woo-Shin;Lim, Joo-Hoon
    • Korean Journal of Environment and Ecology
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    • v.29 no.4
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    • pp.508-515
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    • 2015
  • Post-fire restoration can affect breeding bird communities and species compositions over a long-term period by determining pot-fire succession, and a long-term monitoring is therefore required to understand its impacts on forest birds. This study aimed to document the effects of post-fire restoration methods on breeding bird communities in three areas: unburned and two burned (nonintervention and intervention with clear-cut logging and planting) stands 13 years after the stand-replacing Samcheok forest fire at Mt. Geombong in Samcheok, South Korea. According to 108 point counts during the breeding season from April to June 2013, we found that the number of individuals, observed bird species, and species diversity index in intervention stands with clear-cut logging and planting were lower than that in nonintervention and unburned control stands. Foraging and nesting guild analysis also showed a lower abundance of foliage searchers, timber drillers, primary cavity nesters and secondary cavity nesters in intervention stands than in the other stands, while no significant difference was detected between the nonintervention and unburned stands. These results imply that an interventional restoration method may deter the recovery of avian breeding communities after forest fires, and also suggest that non-interventional restoration methods may be an effective way to benefit the species diversity and density of breeding bird communities.

A Study on Wind Distribution of Mountain Area by Spot Measurements and Simulations (실측 및 해석을 통한 단순 산악지형의 바람장 분포 연구)

  • Kimg, Eung-Sik;Lee, Byung-Doo;Cho, Min-Tae;Kim, Jang-Whan
    • Fire Science and Engineering
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    • v.28 no.6
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    • pp.13-21
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    • 2014
  • Forest fire has a number of variables and since the effects of wind fields are bigger than any other variables, it is essential to know wind direction and velocity for the forest fire extinguishing techniques and the prediction of fire spread. With regards to the local area that has a high chance of forest fire, the data from meteorological observatory in the area is used for the estimation of wind velocity. It is relatively easy to obtain automatic weather station (AWS) data which are available for the whole nation. There is a chance that the data from the weather station may be different with the actual data at the mountain areas. In this study simply shaped hills (Sae-byeol hill of Jeju Island and port Ma-geum in An-myeon Island in the sea side) were selected as the experimental locations to minimize the distortion of the wind field by the adjacent geographic features. Spot measurements and analysis of computational fluid dynamics (CFD) for the given geographic features were conducted to examine and compare their consistency. As a conclusion It is possible to predict wind patterns in these simple locations.

Effects of Forest Therapy Program on Stress levels and Mood State in Fire Fighters (산림치유프로그램이 소방공무원의 외상 후 스트레스 및 기분상태 변화에 미치는 효과)

  • Park, Choong-Hee;Kang, Jaewoo;An, Miyoung;Park, SuJin
    • Fire Science and Engineering
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    • v.33 no.6
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    • pp.132-141
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    • 2019
  • This study was conducted to investigate the effects of a forest therapy program on post-traumatic stress disorder (PTSD) and mood states of fire fighters. A total of 293 participants completed two psychological questionnaires before and after the program was conducted: the Post Traumatic Stress Disorder Checklist (PCL) and the Profile of Mood States (POMS). Data were analyzed with paired t-test and ANCOVA using SPSS 24.0. The PTSD results showed a significant decrease from 11.38 ± 12.58 points before the program to 6.91 ± 10.50 points after the program. Results of the POMS questionnaire revealed an increase in positive factors and a decrease in negative factors, with a significant overall decrease in POMS results from 8.58 ± 18.47 points before the program to -0.63 ± 15.83 points after the program. As a result of analyzing the differences in stress reduction effects according to the amount of sleep participants had, PTSD showed improvement at 6-8 hours of sleep. These results are expected to be utilized as a basis for stress management and relief in fire fighters.

Development of a Gangwon Province Forest Fire Prediction Model using Machine Learning and Sampling (머신러닝과 샘플링을 이용한 강원도 지역 산불발생예측모형 개발)

  • Chae, Kyoung-jae;Lee, Yu-Ri;cho, yong-ju;Park, Ji-Hyun
    • The Journal of Bigdata
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    • v.3 no.2
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    • pp.71-78
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    • 2018
  • The study is based on machine learning techniques to increase the accuracy of the forest fire predictive model. It used 14 years of data from 2003 to 2016 in Gang-won-do where forest fire were the most frequent. To reduce weather data errors, Gang-won-do was divided into nine areas and weather data from each region was used. However, dividing the forest fire forecast model into nine zones would make a large difference between the date of occurrence and the date of not occurring. Imbalance issues can degrade model performance. To address this, several sampling methods were applied. To increase the accuracy of the model, five indices in the Canadian Frost Fire Weather Index (FWI) were used as derived variable. The modeling method used statistical methods for logistic regression and machine learning methods for random forest and xgboost. The selection criteria for each zone's final model were set in consideration of accuracy, sensitivity and specificity, and the prediction of the nine zones resulted in 80 of the 104 fires that occurred, and 7426 of the 9758 non-fires. Overall accuracy was 76.1%.