• Journal of Forest and Environmental Science
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• 제31권2호
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• pp.78-90
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• 2015

Short rotation woody crops belonging to the genera Populus L., Salix L., Pinus L., and Eucalyptus L'Her. have provided broad economic and ecological benefits throughout the world, including afforestation and reforestation along urban to rural gradients. Within the genus Populus, cottonwoods, poplars, aspens, and their hybrids (hereafter referred to as poplars) have been shown to exhibit favorable genotype ${\times}$ environment interactions, especially in the face of changing climates. Similar growth responses have been reported for Pinus, especially with white pine (Pinus strobus L.) in the North Central United States. This has led to current research priorities focused on ecosystem services for both genera. The Millennium Ecosystem Assessment (2005) defines cultural, supporting, provisioning, and regulating ecosystem services. The overarching objective of this paper was to synthesize information about the potential of poplars to provide multiple ecosystem services when grown at sites with varying soil and climate conditions across landscape gradients from urban to rural areas. Specific objectives included: 1) providing background of the United States Forest Service and its Research and Development branch, 2) integrating knowledge of current poplar breeding and development with biomass provisioning and carbon regulating ecosystem services as they relate to changing climates in the North Central United States, and 3) providing a case study illustrating this integration through comparisons of poplar with white pine. Our results were evaluated in the context of climate change mitigation, with specific focus on selection of favorable genotypes for sequestering atmospheric carbon and reducing fossil fuel carbon emissions.

• Journal of the Korean Wood Science and Technology
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• 제39권1호
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• pp.86-94
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• 2011

열분해 온도와 체류시간을 달리하며 급속 열분해 공정을 통해 얻어진 백합나무 바이오오일로부터 분말 형태의 열분해리그닌(pyrolytic lignin)을 회수하였다. 바이오오일을 구성하고 있는 열분해리그닌의 특성을 이해하고 급속 열분해 실험 조건 - 반응 온도, 체류시간 - 이 열분해 과정에서 리그닌에 미치는 영향을 살펴보기 위해 수율을 비롯한 다양한 화학적, 구조적 분석을 수행하였다. 열분해 온도가 증가하고, 체류시간이 줄어들수록 바이오오일로부터 회수되는 열분해리그닌의 수율은 증가하였다. 열분해리그닌의 분자량은 백합나무 MWL (milled wood lignin)에 비해 1/10 수준인 약 1,200 mol/g로 측정되었다. 열분해리그닌 내 포함된 작용기 함량과 $^{13}C$ NMR 분석을 통해 바이오매스가 열분해되는 동안 탈메톡실화 반응과 리그닌의 propane side chain 분해반응이 우세하게 일어난다는 사실을 확인하였다.

• Journal of the Korean Wood Science and Technology
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• 제39권5호
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• pp.406-419
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• 2011

This study was carried out to offer basic information on the wood anatomy of domestic yellow-poplar (Liriodendron tulipifera L.), a new plantation species selected by Korea Forest Service as one of the promising hardwood and bioenergy sources of the future, through comparison of stem wood with root wood in the qualitative and quantitative features. In the qualitative anatomical features, growth rings were distinct in stem wood but relatively less distinct in root wood. And stem wood appeared to have pores in radial multiples of 2 to 5, sometimes clusters but root wood to have pores in radial multiples of 2 to 3, rarely clusters. And numbers of bars in scalariform perforation plates were somewhat numerous in vessel elements of root wood than in those of stem wood. Interestingly, on the other hand, more extraneous materials in the wood rays of tap root than in those of lateral root and stem were confirmed in the chemical composition analyses. In the quantitative anatomical features, pore densities were significantly greater but vessel elements were considerably narrower in stem wood than in root wood. Vessel elements and wood fibers of root wood were considerably longer than those of stem wood. Rays were somewhat more numerous in stem wood than in root wood, and only ray heights of stem wood were more or less greater in cell numbers but both ray heights and widths of stem wood were lower in dimension than those of root wood. The anatomical differences between stem wood and root wood were thought to be associated with different growth environments between the stem above ground and the root below ground.

• Journal of the Korean Wood Science and Technology
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• 제43권5호
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• pp.600-612
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• 2015

We investigated the optimization of the organosolv pretreatment of yellow poplar for bioethanol production. Response surface methodology was used to determine the optimal conditions of three independent variables (reaction temperature, reaction time, and sulfuric acid (SA) concentration). Reaction temperature is the most significant variable in the degradation of xylan and lignin in the presence of an acid catalyst, and ethanol production increased with a decrease in the lignin content. The highest ethanol concentration ($42.80g/{\ell}$) and theoretical ethanol yield (98.76%) were obtained at $152^{\circ}C$ (2.5 bar) with 1.6% SA for 16 min. However, because of excessive degradation of the raw material, the overall ethanol yield was less than under other pretreatment conditions which has approximately 50% of WIS recovery rate after pretreatment. The optimal conditions for the maximum overall ethanol yield ($146^{\circ}C$ with 1.22% SA for 15.9 min) were determined with a predicted yield of 17.11%, and the experimental values were very close (17.15%). Therefore, the quadratic model is reliable.

• KSBB Journal
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• 제4권3호
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• pp.276-280
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• 1989

Phenol / /;H^2O$를 유기용매로 사용하여 이태리 포플라(Populus euramericana)를 무촉매와 산촉매(HCI)하에서 170, 180, 190, 20$0^{\circ}C$에서 각각 30, 60, 90분간 전처리 하였다. 각 조건에서의 목분수율, 리그닌 제거율, 그리고 효소 가수분해에 의한 당화율을 비교 검토하였다. 무촉매하에서의 전처리 결과, 전체 목분수율은 71.5(17$0^{\circ}C$, 30분)에서 41.8%(20$0^{\circ}C$, 90분)의 분포를 보였고, 19$0^{\circ}C$, 60분 조건에서 가장 높은 전처리 효과를 나타내였는 바 이 때의 리그닌 제거율은 98.2%로서 거의 대부분이 추출되었으며 72시간 효소 가수분해 결과 생성된 전체 환원당 농도는 43.9g/1였고 전화율(당화율)은 83.4%였다. 이때 전체 환원당중 glicose의 농도는 36.2g/l로 82.5%를 차지하였다. 산촉매(HCL)를 사용하였을때는 무촉매에 비해 13.1$\pm$3.45%의 낮은 목분수율을 보였고 16.53$\pm$13.15%의 높은 리그닌 제거율을 나타내었다. 가장 높은 당화율은 17$0^{\circ}C$, 60분에서 전처리한 것으로 59.1%였다. 따라서 산촉매하에서의 당화율이 무촉매의 경우보다 훨씬 낮아 산촉매가 부적합함을 보였다.

• 한국신재생에너지학회:학술대회논문집
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• 한국신재생에너지학회 2009년도 추계학술대회 논문집
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• pp.520-520
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• 2009

Organic by-products derived from cellulose and lignin during organosolv pretreatments of yellow poplar wood (Liriodendron tulipifera) in the presence of $H_2SO_4$ and NaOH as catalysts, respectively, were subjected to various analyses to elucidate their effects on further performance of biological ethanol fermentation and provide preliminary data for the structure and utilization of organosolv lignin. Monomeric sugars amounted to ca. 2.2-7.7% in the organosoluble fraction of the organosolv pretreatment with $H_2SO_4$, while significantly low amount of sugars (0.2-0.3%) were determined in that of the organosolv pretreatment with NaOH. In case of addition of $H_2SO_4$ during organosolv pretreatment of biomass, a fermentation of the organosoluble fraction could be considered as an essential process to increase an efficiency of biomass utilization as well as yield of bioethanol. Precipitates, insoluble by-products in the solvent mixture, were also cficiency oed by diverse analytical methods and revealed that these were typically composed of a lignin moiety regardless of catalyst. According to the results of nuclear magnetic resonance (NMR), Fourier Tcinsform Infrared Spectroscopy (FT-IR) and Gel permeation chromatograp r (GPC), the main components of precipitates seem to be lignin polymers. However, their structures could be slightly modified during pretreatment and mixed with some carbohydrates by chemical bonds and/or physical associations.

• Journal of the Korean Wood Science and Technology
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• 제14권3호
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• pp.23-29
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• 1986

성(省) 에너지적 관점에서 목질자원의 식량자원화의 가능성을 검토하기 위하여 속성수종인 현사시나무를 공시수종으로 하여 alkaline peroxide를 사용하여 탈리그닌화의 적정조건을 규명하였던 바, 25$^{\circ}C$에서 100시간 동안 1% $H_2O_2$(pH 11.5)로 반응시킨 것이 당화율과 분해율이 가장 높았다. 이 조건하에서 생산된 당은 주로 glucose and xylose로 구성돼 있으며, 당화효율과 분해율 무처리재에 비해 각각 260%와 350%의 증가를 나타냈으며, 이같은 조건은 1% NaOH와 20% Peracetic acid로 전처리한 목분의 그것과 대비될만한 것이다.

• 한국농공학회논문집
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• 제57권1호
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• pp.25-35
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• 2015

As livestock manure treatment is becoming a problem, manure application in forest plantation is recommended as an alternative. In this study, to investigate the impact due to liquid manure application in forest plantation, soil, soil water and shallow groundwater quality had been monitored in poplar experimental site where the liquid manure (LM) was applied. Water samples were collected weekly during growing season (April to October) from 2008 to 2011. From the monitoring results, phosphorus concentration in the soil and soil water had no significant difference between LM and control plots. $NO_3$-N concentration of soil water in LM, however, showed higher concentration (13.6 mg/l at 40 cm, 35.1 mg/l at 80 cm) than control plot (1.5 mg/l at 40 cm, 0.5 mg/l at 80 cm). In case of shallow groundwater quality, pH, heavy metal, etc. were satisfied to the national agricultural water quality standard of groundwater and there were no significant difference between upstream and downstream. The $NO_3$-N concentration of shallow groundwater was also not exceeded the national drinking water standard. However, $NO_3$-N concentration in soil water and downstream of shallow groundwater had increased in 2011 when non-composted LM was applied mostly in non-growing season of tree (September). From the results, it is important to control nitrogen source, application time and decomposed or not when LM is applied. In addition, to investigate nitrate source, further long-term monitoring and modelling could be necessary.

• 한국자원식물학회지
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• 제17권1호
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• pp.28-33
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• 2004

본 연구는 개량 포플러 현사시 3호를 재료로 제초제 저항성 유전자 PAT으로 형질전환시 킨 다음 제초제 Basta처리에 의한 효율적인 형질전환체 선발을 목적으로 시험되었다. Basta 처리에 따른 캘러스유도, 부정아유도 및 액아유도 시험을 통해 조직치사 농도는 1.0mg/L로 결정할 수 있었으며, 이 농도처리에 의해 형질전환체의 조기선발에 사용하였다. 이 농도처리로 비형질전환체는 모두 고사되었지만, 형질전환체는 정상적으로 반응을 보이며, 생육이 가능하였다 .한편, 형질전환체에 제초제를 직접 살포한 결과, 정상적 생육이 가능했고, PAT activity측정 결과에서도 양성 반응을 나타내어 현사시 3호 세포내에 PAT유전자가 정상 발현됨이 확인되었다. 이로써 현사시에 PAT유전자 도입 및 발현을 위하여 제초제 Basta 처 리와 PAT assay가 매우 효과적인 것으로 나타났다.

• Journal of the Korean Wood Science and Technology
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• 제28권2호
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• pp.66-74
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• 2000

아까시나무의 목질부와 현사시나무, 물푸레나무 및 느릅나무의 수피를 채취하여 아세톤-물의 혼합용액으로 추출한 후 hexane, chloroform, ethylacetate 및 물 분획으로 분류하고 동결건조하며 생리활성 시험용 추출분말을 조제하였다. 각 수종의 목질부에서 채취된 목재 블록에 대하여 수행된 내후성 시험은 아까시나무가 가장 우수하였으며 현사시나무가 가장 낮은 내후성을 나타내었다. 목질부 또는 수피부 추출물에 대한 항진균, 항세균 및 항산화 활성 시험이 수행되었으며 항진균 및 항세균에 대한 활성 시험에서는 모든 분획에서 유의적인 차이를 나타내지 않았다. 항산화 활성 시험은 천연 항산화제인 ${\alpha}$-tocopherol과 합성 항산화제인 BHT를 표준물질로 사용하여 추출물 분획의 항산화 활성과 비교하였다. 이 시험에서 물푸레나무의 ethylacetate 분획이 BHT를 제외하고 가장 높은 활성을 나타내었으며 아까시나무는 모든 분획이 다른 수종보다 높은 활성을 나타내었다.