• Journal of The Korean Society of Grassland and Forage Science
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• v.4 no.3
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• pp.187-193
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• 1984

Using the stratifying clip method, we examine the differences in vertical distribution of leaf area and its relationships with dry matter production were investigated in the primary swards of six varieties. The results obtained were as follows: 1. The varieties could be classified into 4 different types according to their of vertical distribution of leaf area within the canopy. Thus, M had a greater leaf area distribution in the base layers and became smaller towards the upper layers, Leto, First and Bundy had the leaf area distribution which was most abundant in the middle layers and became smaller towards the base and the upper layers, Tammisto had a greater leaf area distribution in the middle layers and intensively distributed to the upper layers, and Trader had the relatively uniform leaf area distribution over all layers. 2. Effective leaf area index(ELAI) correlated with leaf area index(LAI), dry weight of plant(DW), stem weight of plant(SW) and stem area index(SAI). 3. The variety with the heading tiller type had the effective leaf area intensively distributed to the upper layers of canopy, but the vegetative type showed a high ratio of effective leaf area index. 4. Varietal differenced was found between the effective leaf area and specific leaf weight(SLW) in each stratum above the layer indicating the highest leaf area density within the canopy. M and Trader had a highly negative significant correlation, but the other varieties was not significant correlation.

• Journal of The Korean Society of Agricultural Engineers
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• v.51 no.5
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• pp.25-34
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• 2009

The objective of this study is to evaluate the future potential climate and vegetation canopy change impact on a dam watershed hydrology. A $6,661.5\;km^2$ dam watershed, the part of Han-river basin which has the watershed outlet at Chungju dam was selected. The SWAT model was calibrated and verified using 9 year and another 7 year daily dam inflow data. The Nash-Sutcliffe model efficiency ranged from 0.43 to 0.91. The Canadian Centre for Climate Modelling and Analysis (CCCma) Coupled Global Climate Model3 (CGCM3) data based on Intergovernmental Panel on Climate Change (IPCC) SRES (Special Report Emission Scenarios) B1 scenario was adopted for future climate condition and the data were downscaled by artificial neural network method. The future vegetation canopy condition was predicted by using nonlinear regression between monthly LAI (Leaf Area Index) of each land cover from MODIS satellite image and monthly mean temperature was accomplished. The future watershed mean temperatures of 2100 increased by $2.0^{\circ}C$, and the precipitation increased by 20.4 % based on 2001 data. The vegetation canopy prediction results showed that the 2100 year LAI of deciduous, evergreen and mixed on April increased 57.1 %, 15.5 %, and 62.5% respectively. The 2100 evapotranspiration, dam inflow, soil moisture content and groundwater recharge increased 10.2 %, 38.1 %, 16.6 %, and 118.9 % respectively. The consideration of future vegetation canopy affected up to 3.0%, 1.3%, 4.2%, and 3.6% respectively for each component.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.35 no.2
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• pp.151-155
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• 1990

A field experiment was conducted to study both the distribution characteristics of shortwave radiation in the soybean canopy and its relationship with dry matter production. The soybean 'Paldalkong' was sown with the space of 45${\times}$10cm at Suwon on May 27. 1988. The extinction coefficient of solar radiation remained constant (0.53) after full canopy was reached. The 31.9% of the incoming solar radiation was transmitted. The reflected radiation from the plant canopy increased lineary with incoming solar radiation (R$^2$=0.9346). As leaf area index become larger than 2.5. the reflected radiation showed more significant linear relationship with the differences in the radiations between incoming and transmitted radiation than incoming solar radiation (R$^2$=0.9558). The mean reflectance during the growing period was 24.7%. A significant linear relationship (R$^2$=0.9930) had been admitted between the accumulated solar radiation intercepted by the canopy and dry matter production of 'Paldalkong' until the 35th day of ripening stage. The conversion efficiency of solar radiation intercepted to dry matter of soybean was 1.45g MJ$\^$-1/.

• Journal of Biosystems Engineering
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• v.36 no.1
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• pp.15-22
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• 2011

An experimental variable rate nursery sprayer was developed to adjust application rates for canopy volume in real time. The sprayer consisted of two vertical booms integrated with ultrasonic sensors, and variable rate nozzles coupled with pulse width modulation (PMW) based solenoid valves. A custom-designed microcontroller instructed the sensors to detect canopy size and occurrence and then controlled nozzles to achieve variable application rates. A spray delivery system, which consisted of diaphragm pump, pressure regulator and 4-cycle gasoline engine, offered the spray discharge function. Spray delay time, time adjustment in spray trigger for the leading distance of the sensor, was measured with a high-speed camera, and it was from 50 to 140 ms earlier than the desired time (398 ms) at 3.2 km/h under indoor conditions. Consequently, the sprayer triggered 4.5 to 12.5 cm prior to detected targets. Duty cycles of the sprayer were from 20 to 34 ms for senor-to-canopy (STC) distance from 0.30 to 0.76 m. Outdoor test confirmed that the nozzles were triggered from 290 to 380 ms after detecting tree canopy at 3.2 km/h. The spray rate of the new sprayer was 58.4 to 85.2% of the constant application rate (935 L/ha). Spray coverage was collected at four areas of evergreen canopy by water sensitive papers (WSP), and ranged from 1.9 to 41.1% and 1.8 to 34.7% for variable and constant rate applications, respectively. One WSP area had significant (P < 0.05) difference in mean spray coverage between two application conditions.

• Journal of Korean Society of Forest Science
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• v.84 no.2
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• pp.186-197
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• 1995

Site-specific allometric equations relating aboveground tree component biomass and leaf area to tree diameter, basal area, sapwood cross-sectional area and sapwood volume were developed using the destructive harvesting method for Pinus rigida Mill., Larix leptolepis Gordon, and Quercus serrata Thunb. stands in Yangpyeong, Kyonggi Province. There were significantly strong correlations between aboveground tree component biomass or leaf area and diameter at breast height (DBH), basal area, sapwood area and sapwood volume. For a similar diameter tree, the three species had a similar stem wood biomass. However, carbon allocation patterns to stem bark, foliage, branch and total aboveground biomass differed among the three species. Specific leaf area and the ratio of leaf area to sapwood cross-sectional area of the three species were significantly different. Allometric equations seemed To be related to leaf habit or leaf longevity. To elucidate the effect of leaf habit or leaf longevity on allometry and canopy characteristics clearly, more intensive studies are needed.

• Journal of the Korean Institute of Landscape Architecture
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• v.23 no.2
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• pp.148-156
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• 1995

This study was conducted to investigate the actual vegetation and plant community structure of the urban forest in Kwangju Metropolitan City. Thirty eight plots in the urban forest were set up by the clumped sampling method. The degree of green naturality, 6 that is artifical planting area covered 10.9% in Kwangju Metropolitan City and Pinus densiflora community covered 48.7% of the actual vegetations of urban forest. Canopy height, Diameter of breast height (DBH) and No. of species in urban forest were 13.5m, 21cm and 24 species, respectively. The soil conditions and community structure of the urban forest were differenced by location of urban and suburban area. The plant communities divided into six groups which were Quercus acutissima community, Q. acutissima-Robinia pseudo-acacia community, Pinus rigida Community, P. rigida-P. densiflora community, P. densifrora-Q. acutissima community and Q, serrata-P. densiflora community. Successional series of the urban forest in the surveyed area were proceeding from P. dinsiflora to Quercus species. The species diversity of plant were high in natural plant community but low in artificial plant community. Tree density in the canopy layer varied from 600ea/ha to 2,800ea/ha.

• Journal of Korean Society of Forest Science
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• v.100 no.3
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• pp.359-366
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• 2011

The objective of this study was to analyze the changes of crown fire hazard possibility from the effects of forest tending works (FTW) in Pinus densiflora stands in Korea. The study sites were located in Youngju (FTW) and Bonghwa (Control) areas. Ten representative sample trees were destructively felled at each areas to analyze the crown fuel characteristics. The results of this study showed that crown fuel moisture content in Youngju and Bonghwa areas were 103.6% and 104.4%, respectively. The needles and twigs with less than 1cm diameter accounted 50.3% of the total crown fuel load in Youngju area and 62.0% in Bonghwa area. On the other hand, it was observed in Youngju that the canopy bulk density was $0.11kg/m^3$ lower but have 1.3 m higher average canopy base height therefore having a possibility of lower crown fire hazard as compared to Bonghwa that had higher canopy bulk density and lower canopy base height.

• The Korean Journal of Ecology
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• v.18 no.3
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• pp.397-408
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• 1995

This study was conducted to analyze the breeding bird community by using guild concept in Mt. Baekwoon Research Forest of Seoul National University. Bird Community was studied by line transect method during the breeding seasons of birds in 1982 and its results were compared and analyzed with the Park et al. Work in 1993. Guilds were characterized by nesting and foraging sites as follows: nesting guild - (H) hole, (C) canopy, (B) bush, (E) edge; and foraging guild - (o) outside, (c) canopy, (b) bush. Bush-nesting guilds such as Tricolor Flycatcher (Ficedula zanthopygia), Blue-and-White Flycatcher (Cyanoptila cyanomelana), Stonechat (Saxicola torquata), Bush Warbler (cettia diphone) and Skylark (Alauda arvensis) had disappeared after ten years. Outside-foraging guilds such as Common Buzzard (Buteo buteo), sparrow Hawk (Accipiter nisus) and Carrion Crow (Corvus corone) also were not observed. There was a sharp decrease of species richness of bush-nesting guild, canopy-foraging guild and bush-foraging guild compared to ten years ago. These decreases indicate that forest environment of this area has been changed for the ten years, and guild concept in this study can be used usefully to elucidate the change of bird community according to the change in forest environment.

• Journal of Korean Society of Forest Science
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• v.88 no.1
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• pp.86-92
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• 1999

Evapotranspiration is one of important variables affecting ecosystem processes such as vegetation distribution and growth. It acts as a limiting factor for natural water resource management. The transpiration of vegetation is mainly determined by climatic factors. The lower slope of the study area was densely forested with Pinus densiflora S. et Z. of 8 m height, and the upper slope was covered with poorly grown Pinus densiflora S. et Z. and Quercus trees. The amount of evapotranspiration was estimated to 590.3 mm/yr by annual water budget method. The canopy resistance of Penman-Monteith model was determined as 99 s/m. Seasonal evapotranspiration can be estimated with the calculated evaporation and the canopy resistance. The amount of evapotranspiration peaked in May. That is considered from both the direct evaporation of intercepted rainfall and the transpiration of vegetation during the dry spring season.

• Proceedings of the KSRS Conference
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• 2003.11a
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• pp.328-330
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• 2003

The land cover of burned area has changed dramatically since Daxinganling forest fire in Northeastern China during May 6 ? June 4, 1987. This research focused on determining the burn severity and assessment of forest recovery. Burned severity was classified into three levels from June 1987 Landsat TM data acquired just after the fire. A regression model was established between the forest canopy closure from 1999 forest stand map and the NDVI values from June 2000 Landsat ETM+ data. The map of canopy closure was got according to the regression model. And vegetation cover was classified into four types according to forest closure density. The change matrix was built using the classified map of burn severity and vegetation recovery. Then the change conversions of every forest type were analyzed. Results from this research indicate: forest recovery status is well in most of burned scars; and vegetation change detection can be accomplished using postclassification comparison method.