• Proceedings of the Korean Environmental Sciences Society Conference
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• 1997.10a
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• pp.1.1-32
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• 1997

Atmospheric monitoring capabilities were established in 1988 by the University of Florida at Duke forest, near Durham. NC: Cary forest, near Gainesville, FL: and Austin forest, near Nacogdoches, TX. Continuous (hourly averaged) measurements of air quality (ozone, nitrogen oxides and sulfur dioxide) and meteorological variables were made at these three low elevation (< 200 meters), rural locations in the southeastern U.S. for more than three years. During the same period at these sites wet and dry acid deposition samples were collected and analyzed on an event and weekly basis, respectively The monitoring locations were selected to determine actual atmospheric exposure indices for southern pine species in support of on-site surrogate exposure chamber studies conducted by Southern Commercial Forest Research Cooperative (SCFRC) investigators. Daily and quarterly averaged ozone maxima were higher (55 ppb) at the northernmost site in the network (Duke forest) in the second and third quarters (spring and summer seasons) and lower (35 ppb) in the first and fourth quarters (winter and fall seasons), when compared to ozone levels at the two southernmost sites (Cary and Austin forests). Seasonal ozone levels at the latter two sites were similar Nitrogen oxieds and sulfur dioxide levels were insignificant (< 5 ppb) most of the time at all sites, although soil emissions of NO at two sites were found to influence nighttime ozone concentrations. Typical maximum quarterly and annual aggregate ozone exposure indices were significantly higher at Duke forest (92.5/259 ppm-hr) than those values observed at the two southern sites (65.6/210 ppm-hr). Acid deposition (wet and dry) components concentrations and deposition fluxes observed at the Duke forest, NC piedmont site, were generally greater, dependent on site and season, than corresponding variables measured at either of the two southern coastal plain sites (Cary and Austin forests). Acid deposition variables observed at the latter two sites were remarkably similar, both qualitatively and quantitatively, although the sites were located 1300 km apart. A comparison of deposition fluxes of elemental nitrogen (NO3, NH4') and sulfur (5042-, SO3) components in wet and dry forms indicated that wet deposition accounts for approximately 70% of the total nitrogen and 73% of the total sulfur input on an annual equivalent basis at all sites.

• Journal of Plant Biology
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• v.5 no.2
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• pp.17-20
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• 1962

Altitudinal zones of Mt. Hanla were geoecologically investigated, and compared with climate index, according to Coniferae distribution. For climatic index, Warmth index was calculated on Mt. Hanla. With the resultsobtained, the altitudinal zones can be classified into the following three zones; Coniferous forest zone: below $43^{\circ}$ (month-degrees) (above 1, 450m) Deci(u)us broad-leaf forest zone: $84^{\circ}$-$43^{\circ}$ (600-1, 450m) Lucidophyllous forest zone: above $84^{\circ}$ (below 600m)

• Korean Journal of Environmental Biology
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• v.34 no.4
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• pp.246-256
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• 2016

The objective of the study was to investigate vascular plants of Mueuido in Incheon from April to October, 2011. The investigation was carried out for mountains (Mt. Horyonggok and Mt. Guksa), coastal areas and annexed islands (Silmido and Somueuido). Vascular plants were found to have 338 taxa, including 90 families, 235 genera, 297 species, 5 subspecies, 32 varieties and 4 forms. Rare and endangered plants designated by Korea Forest Service had 5 taxa including Utricularia bifida, U. vulgaris var. japonica, U. racemosa, Ottelia alismoides, and Arisaema heterophyllum. The floristic regional indicator plants found in this area had 3 taxa of grade V and 5 taxa of grade III. Naturalized plants consisted of 20 taxa that made up 8.3% of the total vascular plants in this area.

• Journal of Korean Society of Forest Science
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• v.99 no.2
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• pp.251-257
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• 2010

Influences of environment (indicated by plant associations) and forest management practices on the distribution of Armillaria spp. and genets (vegetative clones) were investigated. A total of 142 isolates of Armillaria was collected from various host trees on pristine and managed sites (thinned and/or fertilized) growing in relatively wet and dry environments in eastern Washington, U.S.A. The incidence of Armillaria spp. was significantly higher in the relatively wetter sites than the relatively drier sites, as indicated by plant associations. However, no differences in Armillaria occurrence were found among different forest management practices (control vs. thinned vs. thinned and fertilized) within both wetter and drier sites. Incidence of Armillaria was significantly different among conifer and shrub species. The highest proportion with Armillaria was found on grand fir (Abies grandis). Based on pairing tests and rDNA sequencing, the 142 isolates were comprised in a total of 20 genets representing three Armillaria species. More diverse Armillaria spp. were found in both relatively wetter and relatively drier sites within the undisturbed control plots, compared to plots disturbed by forest management practices. The results from this study provide baseline information toward understanding how environment and forest management practices influence incidence and diversity of Armillaria species and genets.

• Proceedings of the Korean Society of Environment and Ecology Conference
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• 2010.04a
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• pp.202-204
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• 2010

• Proceedings of the Korean Society of Environment and Ecology Conference
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• 2005.10a
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• pp.100-101
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• 2005

• Journal of Korean Society of Forest Science
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• v.90 no.1
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• pp.1-9
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• 2001

The objectives of this study were to explain market structures of logs imported to Korea from U.S.A., New Zealand. Chile. The demand for imported logs is modeled as a function of output of wood manufacturing in Korea and log prices of competing suppliers. It is hypothesized that the quantity of log impaled in a period is determined by its own and competing prices and the output of wood corresponding manufacturing sector in the current period. Import demand functions of logs imported to Korea from U.S.A., New Zealand and Chile were estimated by SURE(Seemingly Unrelated Regression Equations). Elasticities of amounts of logs imported to Korea from U.S.A., New Zealand and Chile with respect to price of imported log from U.S.A. were -2.88, 1.36 and 3.17, respectively. Elasticities of amounts of logs imported to Korea from U.S.A., New Zealand and Chile with respect to price of imported log from New Zealand were 0.71, -1.65 and 1.44, respectively, Elasticities of amounts of logs imported to Korea from U.S.A., New Zealand and Chile with respect to price of imported log from Chile was -2.88. 1.36 and 3.17.

• Proceedings of the Korea Technical Association of the Pulp and Paper Industry Conference
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• 2011.10a
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• pp.289-296
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• 2011

Recently, much of forest biomass has been obtained from the national forest management operation. Unfortunately, Korean Forest Services has a plan to use this forest biomass as energy fuels for wood pellets. Considering unhappy situation that about 80% of wood pulps has been imported, it is regarded as unwise decision. If forest biomass can be used to make pulps or other valuable woody products, we are able to double its economic value than the raw materials for wood pellets. In this study, we explored alternative raw materials for wood biomass used to make wood pellets. For this, fresh technology such as torrefaction was applied with the other lignocellulosic biomass.

• Proceedings of the KSRS Conference
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• v.1
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• pp.512-515
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• 2006

Forest stand height and volume are important indicators for management purpose as well as for the environmental analysis. Shuttle Radar Topography Mission (SRTM) is backscattered over forest canopy and DSM can be acquired from such scattering characteristic, while National Elevation Dataset (NED) provides bare earth elevation data. The difference between SRTM and NED is estimated as tree height, and it is correlated with forest parameters, it is correlated with forest parameters, including average DBH, Trees per acre, net BF per acre, and total Net MBF. Especially, among them, net Board Foot(BF) per acre is the index that well represents forest volume. The Project site was Douglas-fir dominating plantation area in the western Washington an the northern Oregon in the U.S. This study shows a relationship of high correlation between the forest parameters and the product from SRTM, NED, and ETM+. This research performs multi regression analysis and regression tree algorithm, and can get more improved relationship between several parameters.

• Korean Journal of Remote Sensing
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• v.22 no.5
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• pp.427-431
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• 2006

Forest stand height and volume are important indicators for management purpose as well as for the environmental analysis. Shuttle Radar Topography Mission (SRTM) is backscattered over forest canopy and DSM can be acquired from such scattering characteristic, while National Elevation Dataset (NED) provides bare earth elevation data. The difference between SRTM and NED is estimated as tree height, and it is correlated with forest parameters, it is correlated with forest parameters, including average DBH, Trees per acre, net BF per acre, and total Net MBF. Especially, among them, net Board Foot(BF) per acre is the index that well represents forest volume. The Project site was Douglas-fir dominating plantation area in the western Washington an the northern Oregon in the U.S. This study shows a relationship of high correlation between the forest parameters and the product from SRTM, NED, and ETM+. This research performs multi regression analysis and regression tree algorithm, and can get more improved relationship between several parameters.