• Journal of Conservation Science
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• v.5 no.1 s.5
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• pp.87-93
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• 1996

This study was carried out to Identify wood and charcoal segments, which were excavated in 1994 at the Seohaean highway construction site along the western coast of Korea ; Tuntaeri, Hwasunggun. We identified the objects excavated at the fire places of the Tuntaeri dwelling sites (early Koryo period ; A. D. $11\~12C$) ; charcoal pieces and 1 wood segment, which was used for the handle of a metal hook. Chestnut(Castanea crenata), deciduous oaks(Quercus spp.) and maple(Acer app.) were identified from the charcoals, whereas the wood segment as willow species(Salix spp.). These species seem to represent warm and wet climate in the middlewest Korea during $11\~12C$.

• Journal of Forest and Environmental Science
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• v.30 no.1
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• pp.76-84
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• 2014

This study was performed to monitor the effects of water level change on changes of landscape, vegetation community, and species diversity of riparian forest. Hantan river dam, study area, has been constructed in the area of Chansoo-myeon, Pocheon-si and Yeoncheon-eup, Yeoncheon-gun, Gyeonggi-do, which is a dam for flood control only in flooding season. Landscape changes were notable after the construction of coffer dam, and the changes were caused by water level increase in areas of riparian forests which consisted of mainly withered willow as a dominant species in the flooding season. It changed vegetation communities of riparian forest from Phragmites japonica and Salix koreensis to Phragmites japonica. Species diversity index was lowest in 2010 when the coffer dam was constructed and showed an increasing trend later. Thus, this study is well in agreement with a previous report that plants of the genus Salix wither by muddy water during flooding and also suggests, controlling water level of river and prediction of water level change's effects should be considered when any facilities are planned.

• Journal of Korean Society on Water Environment
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• v.32 no.2
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• pp.135-141
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• 2016

This study investigated changes of hydrology, soil characteristics, riparian vegetation communities, and geomorphology in sandbars before and after sand-mining to determine the effect of sand-mining at upstream of Guemgang and Bochungcheon streams in Korea. Sand-mining events affected the mining area. They supplied organic matters and nutrients during flood. Sediment deposition caused soil texture change and expansion of vegetation area. However, riverbeds were stabilized after the disturbance. According to the analyses of aerial photographs, the vegetation area was significantly expanded in both dam-regulated streams and dam-unregulated streams after sand-mining. Willow shrubs advanced in disturbed area at an average of 10 years after sand-mining. It took willows trees 10.6 years to become dominant communities. Therefore, it took a total of 20.6 years for new riparian forest to form in sandbar after sand-mining. Our results confirmed that stream flow condition were dependent on vegetation recruitment in dam-regulated streams and dam-unregulated streams. For willow recruitment in unregulated streams, calculation of water level below dimensionless bed shear stress is important because low water level variation is a limiting factor of vegetation recruitment.

• Journal of Korean Society of Forest Science
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• v.86 no.2
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• pp.177-185
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• 1997

The influences of fertilizer treatment and clones of five willows and one hybrid poplar on above ground and soil carbon (C) accumulations in a willow bioenergy plantation were studied. The aboveground and soil samples were collected in the winter of 1992 and 1993 from the previously established willow plantation at Tully, New York, U.S.A. in 1987. Half of the plots were fertilized annually with 336kg/ha N, 112kg/ha P, and 224kg/ha K. All trees were harvested annually. The most productive clone, willow clone SV1 with fertilization, accumulated 5.4 and 6.8 t/ha/yr aboveground C contents during the sixth(1992) and seventh(1993) growing seasons, respectively. The average percentage of C in bolewood, bolebark, and branches for the five willow clones and one hybrid poplar clone ranged from 51.1 to 57.5, from 54.0 to 55.4, and from 55.6 to 56.5, respectively, among all treatment combinations. Only tyro of the six clones(SA22 and SA2) responded significantly to the addition of fertilizer by increasing the amount of aboveground C accumulated for the 1992 sampling period(clone-by-fertilizer interaction). No fertilization effect, on aboveground C content, was noted for the 1993 sampling period. No significant fertilization effect on soil C accumulation for all soil sampling depths(0-10, 10-20, and 20-40cm) was found in 1992 and 1993 sampling years. Little clone effect on soil C content was found in 1992 and 1993 sampling years, except at 0-10cm soil depth in 1992. The significant clonal effect on soil C content at 0-10cm soil depth could be because of stone content variation rather than clonal effect. The significant clone-by-fertilizer treatment interaction observed requires that evaluation of response to fertilization by willows be made for each clone individually.

• Journal of Forest and Environmental Science
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• v.27 no.3
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• pp.143-149
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• 2011

The possibility of employing biomass of Salix viminalis cv. Q683 as a resource of bio-energy was evaluated. The chemical analysis of S. viminalis cv. Q683 leaf biomass showed components such as, extractives (2.57%), lignin (39.06%), hemicellulose (21.61%), and cellulose (37.83%), whereas, its stem was composed of extractives (1.67%), lignin (23.54%), hemicellulose (33.64%), and cellulose (42.03%). The biomass of S. viminalis cv. Q683 was saccharified using two enzymes celluclast and viscozyme. The saccharification of S. viminalis cv. Q683 biomass was influenced by enzymes and their strengths. The optimal enzyme combination was found to be celluclast (59 FPU/g substrate) and viscozyme (24 FBG/g substrate). On saccharification the glucose from leaf and stem biomass was 7.5g/L and 11.7g/L, respectively after 72 hr of enzyme treatment. The biomass and enzyme-treated biomass served as the feedstock for ethanol production by fermentation. The ethanol production from stem and leaf biomass was 5.8 g/L and 2.2 g/L respectively, while the fermentation of the enzymatic hydrolysates yielded 5 g/L to 8 g/L bioethanol in 72 hours.

• Journal of Forest and Environmental Science
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• v.39 no.4
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• pp.246-253
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• 2023

Salix gracilistyla is widely distributed along riversides in Korea and very good for biomass production by SRC because of its excellent germination ability, but it is necessary to measure drying tolerance for cultivation. The drought tolerance of S. gracilistyla was tested using cuttings, and growth and physiological analysis were performed after irrigation was stopped. The growth inhibition of S. gracilistyla was observed from the day irrigation was stopped, and the soil moisture content decreased to less than 10% on the 25th day after irrigation was stopped. Over 50% of the seedlings turned brown 25 days after watering was stopped. The chlorophyll content of S. gracilistyla decreased dramatically after 25 days of stopping of irrigation. RWC values were unchanged until day 12 after irrigation was stopped but decreased rapidly until day 21, but there was a slightly decreasing trend after that. RWL levels increased slightly during irrigation stops. The proline content of plants subjected to drought stress was 0.91-2.63 mg/0.05 g, 2.75 times higher than that of the control treatment. The sugar content of the drought stress treatment group was 29.77 to 350.66 mg/0.05 g, which increased 12.24 times that of the control treatment. As a result of this study, S. gracilistyla was found to have a drought tolerance almost comparable to that of evergreen broad-leaved trees growing on the land. This study is expected to contribute to the resource utilization S. gracilistyla, a native willow tree of Korea, and the mass production of biomass by SRC.

• Korean Journal of Soil Science and Fertilizer
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• v.31 no.4
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• pp.384-391
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• 1998

Nutrient removal during stem harvest was evaluated in a one-year rotation willow bioenergy plantation. For the stem nutrient content, the stem biomass and stem nutrient concentration were collected in the winter of 1987-1993 from the established willow plantation at Tully, New York, U.S.A. in 1987. Five willow clones and one hybrid poplar clone were planted. Half of the plots were fertilized annually with $336kg\;ha^{-1}$ N, $112kg\;ha^{-1}$ P, and $224kg\;ha^{-1}$ K. All trees were harvested annually. Mean annual nutrient removals of N, P, K, Ca, and Mg by annual stem harvesting over seven years were respectively 30-70, 4-10, 14-40, 19-59 and $3-5kg\;ha^{-1}$. Fertilized plants exported higher quantities of nutrients than non-fertilized ones. Nontheless, quantities of nutrients exported were well below the quantities supplied by fertilization suggesting that nutrients removal by stem harvesting is not likely to cause a decrease in soil fertility. However, in non-fertilized plots, the amount of nutrients removed could result in decrease of nutrient availability and soil fertility over the long-term. An evaluation of the clones revealed that clone SV1 is the most nutrient efficient.

• Journal of Korean Society of Forest Science
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• v.107 no.1
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• pp.16-24
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• 2018

This study was investigated to select superior population and clones of Salix gracilistyla for promoting woody biomass resources through creating of short rotation coppices (SRC). Plant materials were collected from seven different population groups of S. gracilistyla and planted at two different nursery sites in Chuncheon and Yongin. Height and root collar diameter showed statistically significant differeces among population, nursery, and annual growth for three years (p<0.01). Aboveground biomass was harvested to investigate dry weight after 3 years from planting, the Youngwol population showed the highest yield as $4.8kg\;DW\;plant^{-1}$ in Chuncheon nursery which was more than double yield compared to the other nursery planted plants. However, Hongcheon and Wonju populations as $3.3kg\;plant^{-1}$, showed the best yield in Yongin nursery. In addition, there was a significant difference between collected populations and nurseries. But there was statistically significant different interaction between population (Pop) and nursery (Nur) (F value = 3.51, p<0.01). Therefore, the superior populations selected by this experiment could be cultivated as an excellent variety for woody biomass resources through the clonal test.

• Korean Journal of Environmental Biology
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• v.33 no.1
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• pp.63-74
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• 2015

The purpose of this study is to provide the basis information for ecological conservation and restoration of Jangdo wetland conservation area through the survey of vegetation diversity and spatial distribution characteristics. Syntaxonomic account of plant communities were carried out field survey by Z.-M. school method at 14 sites and relationship analysis between plant community and environment variables with Principal Coordinate Analysis (PCoA). Based on the floristic composition, all the plots were classified into xeric and hydric type and arranged in seven plant communities. Spatial distribution of plant communities is determined primarily by the soil moisture condition and amount of organic matter. Hydric vegetation is around 8% ($7,337m^2$) of the protected area and distributed swamp forest of dominating willows under 18 years. Proliferation of willows are recognised extended from edge to centre after in 1990's caused by fallow and control of livestock grazing on wetland. Jangdo wetland will have to readjust the protection boundary because wet meadow zone and swamp forest have been distributed outside the protection area.

• Journal of the Korean Wood Science and Technology
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• v.45 no.3
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• pp.268-277
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• 2017

In this study, lignocellulose nanofibrils (LCNFs) were prepared from Pussy willow wood powder by disk-milling after pretreatment using the cosolvent of 1-ethyl-3-methylimidazolium acetate ([EMIM]Ac) and N,N-dimethylformamide (DMF) with different mixing ratios for different time. All pretreated samples showed native cellulose I polymorph and cellulose crystallinity was lowest when cosolvent of DMF with 30% [EMIM]Ac was used. Average crystallite size of raw material and the pretreated product by MDF and its cosolvent with 10% [EMIM]Ac was found to be about 3.2 nm and decreased with increasing pretreatment time at the DMF cosolvent with 30% [EMIM]Ac. Defibrillation efficiency was improved by loosening wood cell wall structure by the pretreatment using co-solvent system of [EMIM]Ac and DMF.