• Animal cells and systems
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• v.7 no.4
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• pp.295-301
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• 2003

Effects of the settlement density of germlings and canopy on settled germlings of Fucus serratus were investigated on the rocky shore of the Isle of Man. The survival of transplanted germlings was mainly determined by parent canopy rather than by initial settlement density of germlings. However, germling growth was greater at low density than at high density and enhanced by canopy removal. Recruitment by natural propagules was stimulated at high settlement density and maximal recruits occurred on caged slides under the canopy. On the experimental slides, tiny snails and sedimentation were ,found. The number of snails was positively related with the settlement density of germ lings indicating that they fed the germlings. Sedimentation and snail number were greater with canopy removal treatments than in canopy intact ones. These indicate that ,canopy sweeping gives benefits to germlings by removing sediment from substrata and protecting them from herbivores. In conclusion, the survival of settled F. serratus germlings is mainly determined by canopy sweeping and their growth is retarded in the presence of a canopy and at high settlement density.

• Proceedings of the KSRS Conference
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• v.1
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• pp.102-105
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• 2006

Forest canopy density is an essentially important for maintaining the diversify flora and fauna in the tropic. But, the natural and human disturbances have an influence over the inconsistency of forest canopy density. So, forest canopy density (FCD) has been threatened in the tropic since a decade. The objective of this study was to examine the dynamics change of the forest canopy density in tropical forest Chitwan, Nepal combine with field survey and remote sensing data. The field survey data of 2001 such as canopy cover percentage, dbh so on and some human disturbances were used. Similarly, Landsat TM 1988 and ETM+ 2001 have also used to predict the dynamic changes of the FCD over the period. Moreover, nonparametric Kruskal- Wallis test has performed for the validation of the results. Data analysis revealed that very few factors i.e. the number of trees, path, and fire had realized statistically significance at P=<0.05. Therefore we concluded that detail analysis could be needed incorporate with additional socioeconomic, climatic, biophysical and institutional factors for the better understanding of the forest canopy dynamic in particular location.

• Proceedings of the KSRS Conference
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• 2003.11a
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• pp.72-74
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• 2003

Forest canopy density is an ideal representative of the forest habitat situations. It can directly or indirectly depict the canopy structure and gap size in the forestland, thus could be applied to assessment of wildlife’s diversit y. Since population survey of vegetation and wildlife diversities is a key issue for sustainable forest ecosystem management, many research efforts have been focused on forest canopy density using multispectral data in the last two decades. Unfortunately, prediction of canopy density using large scaling remote sensing data remains a challenging issue. Due to recent advances in hyperspectral image sensors hyperspectral imagery is now available for environmental monitoring. In this paper, we conduct experiments to monitor complicated environments of forestland that can be captured by using hyperspectral imagery and further be analyzed to test a prediction model of forest canopy density. The results show that 95% of canopy density could be well described by using 2 difference vegetation indices (DVIs), which are difference of blue and green reflectances rband_100-rband_150 and difference of 2 short wave infrared reflectancse rband_406-rband_410 With the wavelengths of band no. 100, 150, 406, and 410 specified by 462.39 nm, 534.40 nm, 918.22 nm and 924.41 nm respectively.

• 한국공간정보시스템학회:학술대회논문집
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• 2005.11a
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• pp.257-270
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• 2005

Many studies states that improperly uprising of infrastructure may cause leading the forest degradation and canopy reduction in many tropical forest of Asian countries. Other studies revealed that habitat destruction and fragmentation, edge effects, exotic species invasions, pollution are provoked by roads. Similarly, environmental effects of road construction in forests are problematic. Similarly, many researches have been indicated that roads have a far greater impact on forests than simply allowing greater access for human use. Moreover, people using river as means of transportation hence illegal logging and felling cause canopy depletion in many countries. Therefore, it is important to comprehend the study about spatial relation of road, river and suburb followed by temporal change of forest canopy phenomena. This study also tried to examine the effect of road, river and suburb in forest canopy density change of Terai forest of Nepal from you 1988 to 2001. So, Landsat TM88, 92 and 001 and FCD (Forest Canopy Density) mapper were used to perform the spatial .elation of canopy density change. ILWIS (Integrated Land and Water Information System) which is GIS software and compatible with remote sensing data was used to execute analysis and visualize the results. Study found that influence of distance to suburb and river had statistically significance influenced in canopy change. Though road also influenced canopy density much but didn't show a statistical relation. It can be concluded from this research that understanding of spatial relation of factors respect with canopy change is quite complex phenomena unless detail analysis of surrounding environment. Hence, it is better to carry out comprehensive analysis with other additional factors such as biophysical, anthropogenic, social, and institutional factors for proper approach of their effect on canopy change.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.30 no.1
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• pp.76-83
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• 1985

A hypothesis that artificial reforming of corn canopy could improve solar light penetration and dry matter production was tested in corn fields (var. Suwon 19) with three planting densities; low (60 ${\times}$ 40cm), medium (60 ${\times}$ 24cm) and high (60 ${\times}$ 16cm). Natural canopy was found that leaf orientations were even over all azimuth but somewhat inclined toward north-south direction and leaf angle ranged 38$^{\circ}$ to 71$^{\circ}$ from horizontal surface. Reforming corn canopy included following treatments: 1) natural canopy planted in north-south rows (natural canopy), 2)east-west plane canopy planted in north-south rows (E-W canopy), 3)east-west plane canopy and upright leaves in north-south rows, 4)north-south plane canopy (N-S canopy) in east-west rows. After corn plots were installed with training system by supporting poles and connecting wires, corn leaves were induced to a reforming direction and tied on wire. Average light intensity at the mid-point of plant height showed 5-10% increases in E-W canopy and in E-W canopy plus upright leaves, but a 2-10% decrease in N-S canopy from natural canopy. At yellow ripe stage, total dry wt. was increased in E-W canopy but not in N-S canopy. The E-W canopy produced 3-10% more grain yield than natural canopy. Though E-W canopy plus upright leaves yielded less at low density, it yielded up to 10% more at higher density. The N-S canopy yielded similar to low compared with natural canopy. These results suggests that reforming canopy toward solar incident direction increases light penetration into lower canopy, photosynthetic efficiency and grain yield, especially at high planting density in corn.

• Korean Journal of Remote Sensing
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• v.28 no.3
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• pp.297-305
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• 2012

This study was performed to estimate forest canopy density (FCD) using airborne hyperspectral data acquired in the Independence Hall of Korea in central Korea. The airborne hyperspectral data were obtained with 36 narrow spectrum ranges of visible (Red, Green, and Blue) and near infrared spectrum (NIR) scope. The FCD mapping model developed by the International Tropical Timber Organization (ITTO) uses vegetation index (VI), bare soil index (BI), shadow index (SI), and temperature index (TI) for estimating FCD. Vegetation density (VD) was calculated through the integration of VI and BI, and scaled shadow index (SSI) was extracted from SI after the detection of black soil by TI. Finally, the FCD was estimated with VD and SSI. For the estimation of FCD in this study, VI and SI were extracted from hyperspectral data. But BI and TI were not available from hyperspectral data. Hyperspectral data makes the numerous combination of each band for calculating VI and SI. Therefore, the principal component analysis (PCA) was performed to find which band combinations are explanatory. This study showed that forest canopy density can be efficiently estimated with the help of airborne hyperspectral data. Our result showed that most forest area had 60 ~ 80% canopy density. On the other hand, there was little area of 10 ~ 20% canopy density forest.

• Korean Journal of Remote Sensing
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• v.22 no.5
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• pp.313-323
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• 2006

Forest Canopy Density is a dynamic process mediated by various natural and anthropogenic factors. It can be changed over time and locations in the same forest type and landscape. However, human dimensions are considered as the primary force of landscape change and subsequent forest canopy loss in tropical regions of the world. Many studies have been indicated that roads have a far greater impact on forests than simply allowing access for human use. Similarly, rivers have been used as means of transportation, hence illegal logging and felling further deplete forest canopy density. The main objective of this study was to investigate the spatio-temporal dynamic alterations of Forest Canopy Density (FCD) across with site associated factors such as biophysical, physical and human interferences in tropical region of Nepal from 1988 to 2001. Landsat TM and ETM+ of 1988 and 2001 were used to assess the spatial and temporal dynamic alterations of FCD. This analysis revealed that distance to human settlements at P=<0.01, rivers, human interferences (path and fire) and species composition had a statistically significance at P=<0.05 level. However, other factors did not show any significant relation. So, we concluded that understanding of dynamic alterations of FCD with respect to factors was quite complex phenomena. Other surrounding environment could also playa significant role. A comprehensive analysis could be required to understand such complexities. Therefore, additional factors such as climatic, biophysical, social, and institutional with respect to spatio-temporal variability should be considered for the better understanding of canopy dynamic.

• Applied Biological Chemistry
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• v.15 no.1
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• pp.41-47
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• 1972

Comparative study on dynamic change of canopy structure during ripening period were carried out by using newly bred high yield rice cultivar (IR 667-Suwon 213) and a commercial variety, Jinhung in relation to nitrogen nutrition. The results were as follows. 1. Canopy structure pattern (vertical distribution of dry matter density at heading)was vertical type for Jinhung and horizontal type for IR 667. 2. The vertical distribution pattern of leaf area density (or weight) in the canopy was central dominant type for IR 667 while apical dominant type for Jinhung. 3. Canopy conservation pattern and percent distribution pattern of leaf area density followed the vertical distribution pattern of leaf area density. 4. Canopy persistence was weaker in IR 667, thus they have smaller canopy conservation ratio indicating faster senescence. 5. Slow supply of nitrogen (sulfur coated urea) showed a trend to change the apical dominant pattern into the central dominant pattern by the conservation of central portion, and it-resulted in higher yield though nitrogen nutrition did little affect canopy pattern. 6. The central and apical dominant pattern appeared to be well matched to the upper leaf-dependent type and the lower leaf-dependent type of grain yield, respectively.

• Journal of Biosystems Engineering
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• v.21 no.3
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• pp.315-324
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• 1996

This study was one of a series of studies on application of machine vision and image processing to extract the geometrical features of plants and to analyze plant growth. Several algorithms were developed to measure morphological properties of plants and describing the growth development of in-situ lettuce(Lactuca sativa L.). Canopy, centroid, leaf density and fractal dimension of plant were measured from a top viewed binary image. It was capable of identifying plants by a thinning top viewed image. Overlapping the thinning side viewed image with a side viewed binary image of plant was very effective to auto-detect meaningful nodes associated with canopy components such as stem, branch, petiole and leaf. And, plant height, stem diameter, number and angle of branches, and internode length and so on were analyzed by using meaningful nodes extracted from overlapped side viewed images. Canopy, leaf density and fractal dimension showed high relation with fresh weight or growth pattern of in-situ lettuces. It was concluded that machine vision system and image processing techniques are very useful in extracting geometrical features and monitoring plant growth, although interactive methods, for some applications, were required.

• Journal of Korean Society for Geospatial Information Science
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• v.20 no.2
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• pp.55-61
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• 2012

The primary factors of the LOS(Line-of-Sight) analysis process are terrain height, camera capacity, and canopy cover. The canopy cover rate differs depending on the changing season, and its value is influenced by the tree density, tree height, and etc. This study generated the canopy cover value based on relationship between NDVI(Normalized Difference Vegetation Index) and DMT(Density Measure % of Tree/Canopy Cover), which is a digital map attribute, and then performed the LOS analysis on six station of test sites. As results, It was found that NDVI and DMT are correlated with each other through the experiments. Based on this finding, new DMT map can be generated using NDVI. Also, There is a difference between the result of visibility analysis using the present DMT and one using a new DMT. Especially, the spatial distributions of the detected visible areas are significantly different between the two visibility analysis results.