• 한국초지조사료학회지
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• 제14권2호
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• pp.120-124
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• 1994

Browse from oriental white oak(Quercus aliena Blume) was analysed for nutritive value and biomass estimation. The content of cmde protein was high on August and September. NDF, ADF and lignin contents were increased with progressing the seasons but IVDMD, TDN, DE and ME levels were not different from the variation of seasons. Tannin content was high on May and June. Basal stem diameter $\times$ height of tress was highly correlated with browse dry weights(r=0.80**) and the linear regression equation are the follows; Y = 8.23 + O.57X(Y = browse dry weight(g), X= basal stem diameter $\times$ height(cm)). Using the traditional cutting method, the amounts of browse was determined as 823 g dry weight per tree, while the new method by the above equation gave a similar results, i. e., 793 g dry weight per tree. The possibility of browse biomass estimation of oriental white oak by the basal stem diameter $\times$ height index was found.

• 한국태양에너지학회 논문집
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• 제36권1호
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• pp.19-26
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• 2016

Biomass has been used for energy sources from the prehistoric age. Biomass are converted into solid, liquid or gaseous fuels and are used for heating, electricity generation or for transportation recently. Solid biofuels such as bio-chips or bio-pellet are used for heating or electricity generation. Liquid biofuels such as biodiesel and bioethanol from sugars or lignocellulosics are well known renewable transportation fuels. biogas produced from organic waste are also used for heating, generation and vehicles. Biomass resources for the production of above mentioned biofuels are classified under following 4 categories, such as forest biomass, agricultural residue biomass, livestock manure and municipal organic wastes. The energy potential of those biomass resources existing in Korea are estimated. The energy potential for dry biomass (forest, agricultural, municipal waste) were estimated from their heating value contained, whereas energy potential of wet biomass (livestock manure, food waste, waste sludge) is calculated from the biological methane potential of them on annual basis. Biomass resources potential of those 4 categories in Korea are estimated to be as follows. Forest biomass 355.602 million TOE, agricultural biomass 4.019 million TOE, livestock manure biomass 1.455 million TOE, and municipal organic waste 1.074 million TOE are available for biofuels production annually.

• 한국연소학회:학술대회논문집
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• 한국연소학회 2013년도 제46회 KOSCO SYMPOSIUM 초록집
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• pp.19-20
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• 2013

The cofiring of renewable fuel in coal fired boilers is an attractive option to mitigate $CO_2$ emissions, since it is relatively low cost option for efficiently converting renewable fuel to electricity by adding biomass as partial substitute of coal. However, it would lead to reduce plant efficiency and flexibility in operation, and increase operation cost and capital cost associated with renewable fuels handling and firing equipment. The aim of this study is to investigate reduction of carbon dioxide at varying percentage of biomass in fuel blend to the boiler biomass, and estimate operation and capital cost. Wood pellet, PKS (palm kernel shell), EFB (empty fruit bunch) and sludge are considered as a renewable fuels for a cofiring with coal. Several approaches by the cofiring ratio are chosen from past plant demonstrations and commercial cofiring operation, and they are evaluated and discussed for CO2 reduction and cost estimation.

• Ocean and Polar Research
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• 제42권1호
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• pp.21-31
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• 2020

Shorebirds migrating along the East Asian-Australasian Flyway (EAAF) have been drastically decreasing due to continuous area loss and quality degradation of intertidal mudflats in the Yellow Sea. Evaluating the current habitat quality by means of habitat carrying capacity estimation could be effective in predicting the magnitude of impacts caused by habitat loss and provide better understanding to improve management strategies. In this study, we estimated the total biomass of Macrophthalmus japonicus, a main prey item of curlews in the Korea peninsular as habitat carrying capacity of the southern intertidal mudflat of Ganghwa Island, one of the key stopover sites for curlews in the EAAF. The result of the estimation took into account spatial differences of prey biomass and the available foraging time by tide patterns. Accordingly, it was found that curlew populations account for 30.26% of the habitat carrying capacity. When we calculated the mean biomass of the area and extrapolated it to the whole area to calculate the total biomass, it was found that the curlews have consumed 10.92% of the total biomass. The results show that the habitat carrying capacity of the southern intertidal mudflat of Ganghwa Island has decreased by 7.8% compared to a study conducted twenty years ago employing the same method. This study shows that there can be considerable differences in the results of habitat carrying capacity estimation between different methods, indicating that various environmental factors that affect the estimation results of habitat carrying capacity must be considered to achieve a more precise analysis and assessment.

• 한국환경생태학회:학술대회논문집
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• 한국환경생태학회 2010년 학술대회 논문집
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• pp.70-73
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• 2010

• 대한공간정보학회지
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• 제19권1호
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• pp.87-96
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• 2011

최근 환경오염으로 인한 기후변화가 문제시 되고 있는 가운데, 지구온난화의 주범인 탄소의 배출 및 저장량 추정이 중요한 이슈로 부각되고 있다. 특히 산림 바이오매스는 대기와 토양 간 탄소 순환의 중요한 매개체로서 전 지구적인 탄소 순환에 잠재적인 영향을 미치기 때문에 이러한 산림 바이오매스의 각종 파라미터를 추정하고 정량화 하려는 노력이 각국에서 진행중에 있다. 그러나 현장조사를 통한 추정은 시간 및 인력낭비가 심하고, 접근이 용이하지 않은 지역에 대한 조사가 어렵기 때문에 원격탐사자료를 이용한 방법이 각광받고 있다. 본 논문은 총 41개의 해외연구 사례를 바탕으로 원격탐사자료를 이용한 산림 바이오매스 추정 연구를 다섯 가지 관점(연구대상지역; 연구대상면적; 생태군계; 원격탐사자료; 추정기법)에 따라 분류하고, 연구사례 및 기반 기술이 제한적인 국내 관련 분야의 기반자료로써 활용할 수 있도록 하고자 하였다. 조사결과 연구대상지역으로는 북미지역이 39%로 가장 많은 연구 사례가 존재하였으며, 연구대상면적에 대한 조사에 있어서는 지역크기를 대 중 소로 분류 시 소규모 지역(3,600km2)의 연구 수가 59%로 가장 많았다. 생태군계의 경우 북쪽 수림대/타이가 지역이 30%로 연구가 활발하게 수행되었고, 원격탐사자료 사용 빈도는 Landsat 시리즈와 LiDAR가 각각 35%, 16%를 차지하였다. 마지막으로 산림 바이오매스 추정기법에 있어서는 회귀분석 방법이 71%로 가장 많이 사용된 것으로 나타났다.

• 대한원격탐사학회지
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• 제25권4호
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• pp.311-320
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• 2009

본 연구는 전라북도 무주군을 대상으로 제5차 국가산림자원조사 자료와 위성영상(Landsat TM-5)자료를 이용하여 산림 바이오매스를 추정하고 이를 토대로 바이오매스 주제도를 작성하고자 하였다. 먼저 국가산림자원조사의 야외 표본점 자료를 이용하여 조사표본점의 단위면적 당 축적을 산출하고, 바이오매스 변환계수를 적용하여 산림 바이오매스를 추정하였다. 본 연구에서는 위성영상 자료를 이용한 산림 바이오매스 추정을 위해 회귀모형을 이용하는 방법과 최근린 기법(k-Nearest Neighbor)을 이용하는 두 가지 방법을 사용하였는데, 이 두 가지 방법에 의해 추정된 산림 바이오매스를 국가산림자원조사 자료에 의한 추정치와 비교하여 최적의 방법을 선정하였다. 추정된 바이오매스 통계량의 비교를 위해 교차대조법을 이용하여 RMSE(Root Mean Square Error)와 평균편의(Mean Bias)를 산출하였는데, 그 결과 두 방법 모두 유사한 추정오차(RMSE: 63.75$\sim$67.26ton/ha)와 편차($\pm$1 ton/ha)를 보여 정확성 면에서는 큰 차이가 없는 것으로 나타났다. 하지만 최근린 기법을 이용하여 산림 바이오매스를 추정하는 것이 효율성 측면에서 보다 유리할 것으로 평가되었다. 최근린 기법에 의해 추정된 무주군의 산림 바이오매스는 약 839만 톤으로 나타났으며 단위면적당 평균은 149톤/ha인 것으로 분석되었다.

• 대한원격탐사학회지
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• 제27권3호
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• pp.389-401
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• 2011

Most nations around the world have expressed significant concern in the climate change due to a rapid increase in green-house gases and thus reach an international agreement to control total amount of these gases for the mitigation of global warming. As the most important absorber of carbon dioxide, one of major green-house gases, forest resources should be more tightly managed with a means to measure their total amount, forest biomass, efficiently and accurately. Forest biomass has close relations with forest areas and tree height. Airborne LiDAR data helps extract biophysical properties on forest resources such as tree height more efficiently by providing detailed spatial information about the wide-range ground surface. Many researchers have thus developed various methods to estimate tree height using LiDAR data, which retain different performance and characteristics depending on forest environment and data characteristics. In this study, we attempted to investigate such various techniques to estimate tree height, elaborate their advantages and limitations, and suggest future research directions. We first examined the characteristics of LiDAR data applied to forest studies and then analyzed methods on filtering, a precedent procedure for tree height estimation. Regarding the methods for tree height estimation, we classified them into two categories: individual tree-based and regression-based method and described the representative methods under each category with a summary of their analysis results. Finally, we reviewed techniques regarding data fusion between LiDAR and other remote sensing data for future work.

• 임산에너지
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• 제18권2호
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• pp.92-99
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• 1999

임분밀도에 따른 소나무림의 biomass생산량, 밀도변화에 따른 임목의 부위별 biomass배분특성 및 교목, 관목, 초본 등 수직층위별 biomass의 분포특성을 파악하고자 중국 백두산 동북부 지역 소나무 천연림에서 연구를 수행하였다. 임분의 밀도를 5등급으로 나누어 각각 교목층, 관목층, 초본층별로 biomass량을 추정하였다. 교목층에서 부위별로 교목층 소나무 biomass량 추정식을 유도한 결과 줄기,수피 및 지상부 전체 biomass량의 경우, logW=a＋blog(D2H)＋c(D2H)식의 적합도가 높게 나타났고 가지, 침엽의 biomass량 및 엽면적의 경우, logW=a＋blogD＋cDtlr의 적합도가 높게 나타났다. 밀도가 증가함에 따라 교목층의 biomass량은 증가하였고 관목과 초본층의 biomass량은 감소하는 추이를 나타내었다. 소나무 천연림내 교목층 임목의 부위별 순생산량은 밀도가 증가함에 따라 모두 증가하였다. 침엽이 지상부 전체 biomass 순생산량 중 차지하는 비율은 밀도가 증가함에 따라 감소함으로써 침엽의 교목층 지상부 biomass량에 대한 생산성은 증가하였다. 밀도가 다른 소나무천연림에서 부위별 순생산량은 모두 줄기>침엽>가지>수피 순이었다.

• 한국산림과학회지
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• 제96권5호
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• pp.602-608
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• 2007

Forest plantations become important strategy not merely for the financial aspect, but for carbon sequestration and ecosystem stability. Forest plantations increase the density of the forest biomass, which reduce the increase in atmospheric carbon dioxide. Biomass density is also a useful variable for comparing structural and functional attributes of forest ecosystems across a wide range of environmental conditions. In this study, carbon sequestration of teak (Tectona grandis Linn. f.) in the individual tree and plantation levels estimation was carried out Site-specific allometric equation for the estimation of teak tree biomass was developed based on the direct measurement of fifteen (15) harvested trees in the Oak-twin Township of the Bago Yoma Region, Myanmar. A regression equation of the diameter at breast height (DBH) and the aboveground biomass (carbon content) was constructed to estimate the carbon storage level of plantations, which averaged 79 ton/ha. The average carbon accumulation in the soil (up to 30 cm in depth) was estimated 38.89 ton/ha, The highest mean annual increment (MAI) of total carbon was found in the 6-yr-old teak plantation (12.10 ton/ha/yr) whereas the lowest MAI was in the 26-yr-old teak plantation (4.31 ton/ha/yr).