• Proceedings of the KSRS Conference
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• 2007.10a
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• pp.642-645
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• 2007

Mounted in aircraft, LiDAR (Light Detection And Ranging) technology uses pulses of light to collect data about the terrain below. The main objective of this study was to extract reliable the individual tree and analysis techniques to facilitate the used LiDAR data for estimating tree crown diameter by measuring individual trees identifiable on the three dimensional LiDAR surface. In addition, this study can be quantitative analysis of individual tree through the canopy parameter.

• Korean Journal of Agricultural and Forest Meteorology
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• v.13 no.2
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• pp.56-68
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• 2011

Wet canopy evaporation ($E_{WC}$) has been recognized as a significant component of total evapotranspiration, especially in forests and therefore it is critical to accurately assess $E_{WC}$ to understand forest hydrological cycle. In this review, I focused on the measurement methods and evaluating the magnitudes of $E_{WC}$ at diverse forest types (e.g., deciduous, coniferous, mixed, and rain forests). I also present the general issues to be considered for $E_{WC}$ measurements. The commonly used measurement methods for $E_{WC}$ include the water balance, energy balance, and the Penman-Monteith (PM) methods. The magnitudes of $E_{WC}$ ranged from 5 to 54% of precipitation based on the literature review, showing a large variation even for a similar forest type possibly related to canopy structure, rainfall intensity, and other meteorological conditions. Therefore, it is difficult to draw a general conclusion on the contribution of $E_{WC}$ to evapotranspiration from a particular forest type. Errors can arise from the measurements of precipitation (due to varying wind effect) and throughfall (due to spatial variability caused by canopy structure) for water balance method, the measurements of sensible heat flux and heat storage for energy balance method, and the estimation of aerodynamic conductance and unaccounted sensible heat advection for the PM method. For a reliable estimation of $E_{WC}$, the combination of ecohydrological and micrometeorological methods is recommended.

• Korean Journal of Remote Sensing
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• v.36 no.2_2
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• pp.325-335
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• 2020

Forest canopy height can be used for estimate of above-ground forest biomass (AGB) by means of the allometric equation. The remote locations and harsh conditions of mangrove forests limit the number of field inventory data stations needed for large-scale modeling of carbon and biomass dynamics. Although active and passive spaceborne sensors have proven successful in mapping mangroves globally, the sensors generally have coarse spatial resolution and overlook small-scale features. Here we generate a 12 m spatial resolution mangrove canopy height map from TanDEM-X data acquired over the world largest intact mangrove forest located in the Sundarbans. With single-pol. TanDEM-X data from 2011 to 2013, the proposed technique makes use of the fact that the double-bounce scattering that occurs between the water and mangrove trees yields water surface level elevation over mangrove forest areas, thus allowing us to estimate forest height with the assumption of an underlying flat topography. Our observations have led to a large-scale mangrove canopy height map over the entire Sundarbans region at a 12 m spatial resolution. Our canopy height estimates were validated with ground measurements acquired in 2015, a correlation coefficient of 0.83 and a RMSE of 0.84 m. With globally available TanDEM-X data, the technique described here will potentially provide accurate global maps of mangrove canopy height at 12 m spatial resolution and provide crucial information for understanding biomass and carbon dynamics in the mangrove ecosystems.

• Korean Journal of Remote Sensing
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• v.35 no.4
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• pp.545-560
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• 2019

Unlike other critical forest diseases, pine pitch canker in Korea has shown rather mild symptoms of partial loss of crown foliage and leaf discoloration. This study used high-resolution satellite images to detect and monitor canopy decline by pine pitch canker. To enhance the subtle change of canopy reflectance in pitch canker damaged tree crowns, multi-temporal analysis was applied to two KOMPSAT multispectral images obtained in 2011 and 2015. To assure the spectral consistency between the two images, radiometric corrections of atmospheric and shadow effects were applied prior to multi-temporal analysis. The normalized difference vegetation index (NDVI) of each image and the NDVI difference (${\Delta}NDVI=NDVI_{2015}-NDVI_{2011}$) between two images were derived. All negative ΔNDVI values were initially considered any pine stands, including both pitch canker damaged trees and other trees, that showed the decrease of crown foliage from 2011 to 2015. Next, $NDVI_{2015}$ was used to exclude the canopy decline unrelated to the pitch canker damage. Field survey data were used to find the spectral characteristics of the damaged canopy and to evaluate the detection accuracy from further analysis.Although the detection accuracy as assessed by limited number of field survey on 21 sites was 71%, there were also many false alarms that were spectrally very similar to the damaged canopy. The false alarms were mostly found at the mixed stands of pine and young deciduous trees, which might invade these sites after the pine canopy had already opened by any crown damages. Using both ${\Delta}NDVI$ and $NDVI_{2015}$ could be an effective way to narrow down the potential area of the pitch canker damage in Korea.

• Korean Journal of Environment and Ecology
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• v.17 no.1
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• pp.1-8
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• 2003

This study was conducted to investigate the effects of road on bird community by line transect census method from May 2000 to January 2001 in Mt. Geumsan, Namhae-Gun, Kyeongsangnam-do. Canopy layer was more developed in forest area than road area. Understory vegetation of road area was more developed than forest area. Twenty six and twenty three bird species were observed in road and forest area, respectively, White's thrush and ashy minivet were observed just only in forest area, and Siberian blue robin, blue-and-white flycatcher and gold crest were in road area. The birds being to bush nesting and foraging guilds in road area were more than forest area. It is known that the road construction was negatively affected on bird community. However, road construction would be not so negative on bird community according to the results of thie study. It would be needed the maintenance of upper canopy layer and understory vegetation to reduce negative effect of road on bird communities in forest area.

• Journal of Korean Society of Forest Science
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• v.35 no.1
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• pp.36-38
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• 1977

Some characteristics of rainfall interception and surface runoff from total rainfall at a forest stand mixed with Pinus densiflora and Alnus hirsuta in 1975 was analysised and the results obtained are as fellow; 1. The annual interception of rainfall by the forest canopy was 19.3 percent to annual rainfall 1,072.7mm. 2. The rate of rainfall interception in the dry season as spring and early summer was of 20 to 50 percent and less than 15 percent in the rainy season as summer. 3. About 50 percent of rainfall was intercepted in case of less than 10mm of every rainfall by the forest canopy and, in more than 20mm, about 20 percent intercepted.

• Journal of Plant Biology
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• v.33 no.2
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• pp.147-150
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• 1990

Different species with similar niches can coexist in the same community if disturbances prevent compeptitive exclusion of competitively inferior species. Disturbances which open up gaps are common in all kind of community. Even in virgin forests without any artificial disturbance, there exist a significant proportion of trees of early successional shade-in-tolerant species in addition to the dominant late successional shade-tolerant species. In forest ecosystems, most canopy tree species including shade-tolerant ones require one or more gaps in their life-time to reach the canopy. Because of these frequent disturbances, forests can be considered of dynamic mosaics of patches of different ages and with different species composition which are in certain stages of recovery from disturbances. Disturbances temporarily increase the availability of resources such as light, water and soil nutrient for other in dividuals through the death of one or more canopy trees.

• Animal cells and systems
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• v.9 no.1
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• pp.41-46
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• 2005

This study was conducted to reveal tree species preference and inter-specific difference of foraging behavior among four canopy-dwelling birds at forest dominated by Quercus mongolica, Acer pseudosieboldian and Carpinus cordata at 1,000 meters above sea level during breeding season of birds from 1995 to 1997 in Mt. Jumbongsan. Breeding birds were about 25 species and dominant birds were Erithacus cyane, Parus ater and Parus palustris. A relatively high number of bush-nesters can be a characteristic of breeding bird community at study area. Three gleaners (Tits, P. varius, P. palustris and P. ater) selectively preferred the trees irrespective of dominant tree species, whereas bark foragers (Nuthatch, Sitta europaea) utilized the dominant trees. The four birds showed significant inter-specific difference in use of foraging location, but the three tits did not show significant inter-specific difference in use of foraging maneuver and trees. Closely related tits may coexist with each other by inter-specific different use of foraging location determined by foliage structure and leaf arrangement.

• Journal of Ecology and Environment
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• v.31 no.2
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• pp.153-159
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• 2008

The timing of the canopy phenology onset (CPO hereafter) indicates the initiation of the growing season, with rapid increases in exchange rates of carbon dioxide and water vapor between vegetation and atmosphere. The CPO is regarded as a potential indicator of ecosystem responses to global warming, but the CPO shows considerable spatial variation depending on the species composition and local temperature regime. at a given geographic location. In this study, we evaluated the utility of satellite observation data for detection of the timing of the CPO. Leaf area indices (LAI) obtained from the Moderate Resolution Imaging Spectrora-diometer (MODIS) were utilized to detect and map the onset dates from 2001 to 2006. The reliability of MODIS-based onset dates was evaluated with ground measured cherry blossom flowering data from national weather stations. The MODIS onset dates preceded the observed flowering dates by 8 days and were linearly related with a correlation coefficient of 0.58 (p < 0.05). In spite of the coarse spatial (1 km) and temporal (8 days) resolutions of MODIS LAI, the MODIS-based onset dates showed reasonable ability to predict flowering dates.

• Korean Journal of Environmental Biology
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• v.27 no.3
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• pp.266-271
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• 2009

This study was about three genus of Viola: V. rossii, V. japonica, and V. dissecta var. chaerophylloides which can live together under a deciduous forest canopy. The aim of the study was to directly compare reproductive characteristics of the three species under the same environmental condition. By taking a census of the morphologically different flowers, the results indicate that all three species opened chasmogamous flowers before the canopy of forest closed, but continuously opened cleistogamous flowers after the canopy closed. Numbers of seeds in a capsule followed an ascending order from V. rossii to V. japonica. Mass of seeds followed a descending order from V. rossii to V. japonica. Both results had statistical significance. In terms of characteristics of seed production, V. rossii has been adapted more than V. japonica, and V. dissecta var. chaerophylloides under the deciduous forest.