• 한국토양비료학회지
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• 제46권5호
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• pp.343-350
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• 2013

The objectives of this study were to estimate the potential biomass yield by using the biomass conversion index and evaluate the potential energy production by using the energy conversion index of biomass. Estimating the total biomass yield in Korea showed 9,646.3 thousand tons produced in 2012. Subsequent evaluation of the potential energy production using the estimated biomass yield in 2012 indicated that the calorific values were varied from 3,800 to 4,500 kcal $kg^{-1}$ for crop- and from 4,100 to 4,300 kcal $kg^{-1}$ for woody-based biomass, respectively. Among the examined biomass materials, the pruned branch of a nut tree appeared to be the greatest in bio-energy production showing 6,300 kcal $kg^{-1}$ in calorific value. Total potential energy production from agricultural by-products was estimated approximately at 3,966,000 TOE. Among the agricultural by-products examined, rice straw showed the greatest energy production potential being at 2,321,000 TOE. Furthermore, it might contribute to establishing the countermeasures of biomass utility in agricultural sector based on regional distribution chart of the potential biomass and energy yields in Korea.

• 대한원격탐사학회:학술대회논문집
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• 대한원격탐사학회 2008년도 International Symposium on Remote Sensing
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• pp.200-203
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• 2008

The objective of this study is to produce the $CO_2$ (carbon dioxide) absorption map using KOMPSAT-2 imagery. For estimating the amount of $CO_2$ absorption, the stand biomass of forest was estimated with the total weight, which was the sum of individual tree weight. Individual tree volumes could be estimated by the crown width extracted from KOMPSAT-2 imagery. In particular, the carbon conversion index and the ratio of the $CO_2$ molecular weight to the C atomic weight, reported in the IPCC (Intergovernmental Panel on Climate Change) guideline, was used to convert the stand biomass into the amount of $CO_2$ absorption. Thereafter, the KOMPSAT-2 imagery was classified with the SBC (segment based classification) method in order to quantify $CO_2$ absorption by tree species. As a result, the map of $CO_2$ absorption was produced and the amount of $CO_2$ absorption was estimated by tree species.

• 한국농공학회논문집
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• 제52권3호
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• pp.39-45
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• 2010

Quantification of carbon absorption and understanding the human induced land use changes (LUC) forms one of the major study with respect to global climatic changes. An attempt study has been made to quantify the carbon absorption by LUC through remote sensing technology. The Landsat imagery four time periods was classified with the hybrid classification method in order to quantify carbon absorption by LUC. Thereafter, for estimating the amount of carbon absorption, the stand biomass of forest was estimated with the total weight, which was the sum of individual tree weight. Individual tree volumes could be estimated with the crown width extracted from digital forest cover type map. In particular, the carbon conversion index and the ratio of the $CO_2$ molecular weight to the C atomic weight, reported in the IPCC guideline, was used to convert the stand biomass into the amount of carbon absorption. Total carbon absorption has been modeled by taking areal estimates of LUC of four time periods and carbon factors for land use type and standing biomass. Results of this study, through LUC suggests that over a period of construction, 7.10 % of forest and 9.43 % of barren were converted into urban. In the conversion process, there has been a loss of 6.66 t/ha/y (7.94 %) of carbon absorption from the study area.

• 한국신재생에너지학회:학술대회논문집
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• 한국신재생에너지학회 2010년도 춘계학술대회 초록집
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• pp.244.2-244.2
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• 2010

Biological conversion of biomass into fuels and chemicals requires hydrolysis of the polysaccharide into monomeric sugars. In this study, dilute sulfuric acid used as a catalyst for the pretreatment of rapeseed straw. Hydrolysis can be performed enzymatically, and with dilute or concentrate mineral acids. Dilute-acid hydrolysis of rapeseed straw was optimized through the utilization of combined severity. Evaluation criteria for optimization of the pretreatment conditions were based on high xylose recovery and low inhibitor contents in the hydrolyzates. In addition, this paper reports the compositional analysis of hydrolyzate liquors and solid residues, xylose and glucose mass balance closures, and digestibility results of the acid pretreated rapeseed straw.

• 한국산림과학회지
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• 제98권3호
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• pp.324-330
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• 2009

본 연구의 목적은 KOMPSAT-2 영상을 이용하여 대상지 내 주요 수종의 이산화탄소 흡수량을 추정하는 것이다. 우선, KOMPSAT-2 영상을 분할영상분류방법으로 산림내 수종을 임상단위로 분류하였다. 분류된 임상의 평균 수관직경을 추정한 후, 이를 각 수종의 면적에 대비시켜 수종별 본수를 추정하였다. 평균 흉고직경은 지상조사를 통해 유도된 수관직경과 흉고직경의 관계식을 이용하여 추정하였다. 이와 같이 추정된 수종별 흉고직경과 본수를 기존의 바이오매스 추정식에 대입하여 수종별 바이오매스를 추정하였다. 바이오매스에 '기후변화에 관한 정부간 패널(IPCC)'의 가이드라인에 따른 계수를 적용하여 임상단위의 이산화탄소 흡수량을 추정했다. 본 연구의 임상단위 수종별 이산화탄소 흡수량 추정 접근방식은 향후, 표본점 단위의 이산화탄소 흡수량을 임상단위 이산화탄소 흡수량으로 확장시키는데 활용될 수 있다.

• Mycobiology
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• 제51권4호
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• pp.239-245
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• 2023

Xylanase has been applied in various sectors, such as biomass conversion, paper, pulp, textiles, and pharmaceutical industries. This study aimed to isolate and screen potential xylanase-producing fungi from the soil of Suphan Buri Province, Thailand. Fifteen fungi were isolated, and their xylanase activities were tested by the qualitative method. The result showed that isolate SP3, SP10 and SP15 gave high xylanase activity with potency index (PI) of 2.32, 2.01 and 1.82, respectively. These fungi were selected for the xylanase quantitative test, isolate SP10 performed the highest xylanase activity with 0.535 U/mL. Through molecular methods using the 𝛽-tubulin gene, isolate SP10 was identified as Penicillium menonorum. The xylanase characteristics from P. menonorum SP10 were determined, including the xylanase isoforms and the optimum pH and temperature. The xylanase isoforms on SDS-PAGE indicated that P. menonorum SP10 produced two xylanases (45 and 54 kDa). Moreover, its xylanase worked optimally at pH 6 and 55 ℃ while reaching 61% activity at 65 ℃. These results proposed P. menonorum SP10 as a good candidate for industrial uses, especially in poultry feed and pulp industries, to improve yield and economic efficiency under slightly acidic and high-temperature conditions.

• 한국농림기상학회지
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• 제23권4호
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• pp.198-221
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• 2021

1960-70년대 대규모 산림녹화 이후에 한국의 산림은 점차 노령화되고 있다. 노령림의 순 CO₂ 교환은 이론적으로 중립에 가깝지만, 교란이나 관리에 의해 CO₂ 흡원 또는 발원이 될 수 있다. 본 연구는 한국의 광릉 낙엽활엽수 노령림(GDK)의 CO₂ 수지 역학을 이해함으로써, 다음 두 가지 질문에 답하고자 하였다: (1) 보전되고 있는 GDK는 과연 이론적으로 알려져 있는 CO₂ 중립인가? (2) 관측된 CO₂ 수지의 경년 변동이 문헌에 보고된 조절 인자들과의 선형적인 인과관계로 설명이 가능한가? 이에 답하기 위해, 본 연구는 KoFlux GDK 관측지에서 에디 공분산 기술로 2006년부터 2020년까지 15년 동안 관측된 CO₂ 플럭스 자료와 생기상학적 자료를 분석하였다. 연구 결과, (1) GDK는 15년 자료를 평균해서 보면 약한 CO₂ 발원이며, 관측기간 동안 흡원과 발원 사이를 오갔으나 최근 5년 동안 CO₂ 발원으로서의 강도가 증가하고 있다. (2) 전천일사, 생장기간, 엽면적지수의 경년 변동은 총 일차생산량(Gross Primary Production, GPP)의 경년변동과 양의 상관관계(R²=0.32~0.45)가 있는 반면, 기온과 지표면 온도의 경년 변동은 생태계 호흡(Ecosystem Respiration, RE)의 경년 변동과 유의한 상관관계가 없었다. 또한, 관측기간 초반(첫 10년)의 CO₂ 플럭스와 기상요인 및 생물학적 요인으로 학습시킨 기계학습은 관측기간 후반(최근 5년)의 GPP와 RE의 경년 변동을 제대로 모사해내지 못했다. 단, 고사목에서 배출된 탄소 추정량이 CO₂ 발원으로의 전환에 일부 기여했을 것으로 추정된다. GDK의 장기 CO₂ 수지 역학에 대해 올바로 이해하고 해석하기 위해서는, 분석과 모델링을 위한 복잡계과학 기반의 새로운 프레임워크가 필요하다. 더불어, 플럭스 모니터링 및 자료 품질 유지와 함께 고사목과 교란을 지속적으로 모니터링하는 것이 중요함을 다시 한 번 확인하였다.