• Journal of The Korean Society of Agricultural Engineers
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• v.49 no.6
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• pp.21-33
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• 2007

Different vegetation indices from satellite images have been used for monitoring drought damages, and this study aimed to develop a drought index using NOAA/AVHRR NDVI(Normalized Difference Vegetation Index) and to analyze the temporal and spatial distribution of spring drought severity in North Korea from 1998 to 2001. A new drought index, DevNDVI(Deviation of NDVI), was defined as the difference between a monthly NDVI and average monthly NDVI at the same cover area, and the DevNDVI images at all years except for 2001 demonstrated the drought-damaged areas referred from various domestic and foreign publications. The vegetation of 2001 showed high vitality despite the least amount of rainfall among the target years, and the reason was investigated that higher temperature above normal average would shift the growing stages of plants ahead. Therefore, complementary methods like plant growth models or ground survey data should be adopted in order to evaluate drought-induced plant stress using satellite-based NDVI and to make up far the distortion induced by other environments than lack of precipitation.

• Journal of Plant Biology
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• v.18 no.3
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• pp.109-121
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• 1975

The seasonal variations of the marine algal community were detected with quadrat method during May, 1974-May, 1975 at several stations in the Kwang Yang Bay. Considering the environmental factors such as salinity and water current, etc., and algal vegetation, the Bay was divided into 3 sections; Section I-Myodo and the adjacent area; Section II-Eomnamuseom and the adjacent area; Section III-inlet of the Bay from Odongdo, Yeosu. The dominant species, shown by 5-grades coverage and bimonthly investigations, appear in the order of Sargassum thunbergii(Jan.)>Chondria crassicaulis (Mar.)>Ulva pertusa(May)>U. pertusa (July)>U. pertusa and Gigartina intermedia(Sept.)> Sarg. thunbergii and Gelidium pusillum (Nov.) in Section I, and Sargassum thunbergii(Jan.)>Ulva pertusa and Hizikia fusiforme (Mar.)>U. pertusa and Sarg. thunbergii(May)>Chondria crassicaulis (Sept.)>Ch. crassicaulis (Nov.) in Section II. The members such as Srgassum thunbergii, Gelidium pusillum, G. divaricatum, Hizikia fusiforme, Carpopeltis affinis, and Chondria crassicaulis show the most luxuriant period of growth in winter (Nov.-Mar.), while Ulva pertusa shows the period in May. However, considering the dry weight of total vegetation, the most luxuriant period apperas in May and the poorest one in July. The total dry weight of the vegetation in Section II is about 3.2 times more than the one in Section I.

• Korean Journal of Environment and Ecology
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• v.12 no.2
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• pp.138-146
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• 1998

Ten plots were established to study the vegetation structure of the Songinbong virgin forest in Ullungdo. It was classified into three communities Fagus crenata var. multinervis commnunity, Acer okamotoanum-Fagus crenata var. multinervis community, and Acer okamotoanum community. Shannon's diversity indicies of this area were not high(0.5150~0.8437), due to the geographical and vegetational characteristics. Considering the community structure(importance value, distribution of DBH class, and so on), the vegetation of the Songinbong virgin forest are thought to be stable continuously. With the analysis of plant growth type, it was presumed that Acer okamotoanum have increased after artificial disturbances in this area where Fagus crenata var. multinervis had been dominanat.

• KIEAE Journal
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• v.13 no.3
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• pp.105-110
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• 2013

Green roof system is classified as intensive greening, extensive greening or mix of intensive-extensive greening. Recently, light-weigh green roof has been performed actively, because buildings have been considered loads, design and maintenance. This study was conducted to design soil depth for light-vegetation block with using bottom-ash. As a result, it was found that growth of plant had no direct effect on soil depth even it was less than 10cm. Soil depth having under 5cm could be integration of plant roots and vegetation blocks. It was also possible to grow organic vegetables through the experiment of planting. According to this experiment, as light-vegetation block with bottom-ash was used for planting, it makes design shallow soil depth. The results will help install green roof system conveniently not only new buildings but also used buildings.

• Proceedings of the Korea Water Resources Association Conference
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• 2009.05a
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• pp.164-168
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• 2009

우리나라 하천의 대부분은 다양한 수리학적, 형태학적 특징을 가지고 있으며 이에 따라 수위-유량관계는 민감하게 변화한다. 그 중 하도구간에 서식하고 있는 식생의 영향은 우리가 쉽게 예측할 수 없는 통제 특성을 발생시킨다. 식생(Vegetation)은 서서히 혹은 빠르게 성장하고, 쉽게 변화하여 기간별로 혹은 주기별로 다른 양상의 수위-유량관계를 발생시키고 이는 레이팅 전이(Rating shift)로 이어진다. 본 연구에서는 식생의 영향에 의해 발생되는 수위-유량관계를 좀 더 명확하게 규명하고자, 영산강 수계 황룡강 중류부에 위치한 임곡 지점을 대상 지점으로 선정하고 주기적으로 유량측정을 실시하여 시기별, 측정성과별로 식생의 정도를 검토하고 그 경향성을 파악하였다. 하도 내에서 수중식물의 성장이 진행되면 흐름 저항의 정도가 변하게 되며, 이의 영향으로 유속 역시 변하게 된다. 식생(Vegetation)의 성장기에는 유속이 감소하여 유량이 작아지는 수위-유량관계의 일차적인 음의 전이가 발생하며, 식생의 성장이 극대화되는 8월에는 좀 더 큰 음의 전이가 발생하게 된다. 하지만 식생에 의한 곡선의 전이(Rating Shift)는 영구적인 것이 아니라 계절별로 순환하는 특성을 지니고 있기에, 식생의 영향이 소멸하기 시작하는 9월 이후에는 수위-유량관계가 식생의 영향이 없는 원래의 수위-유량관계로 다시 접근하는 것을 확인할 수 있었다. 결과적으로 본 연구에서는 식생의 영향이 없는 수위-유량관계곡선(Original rating curve)을 개발하고 식생의 성장 및 영향의 정도에 따른 기간분리를 실시하여 전이된 수위-유량관계곡선(Shift curve)을 개발하였다. 아울러 전체적인 유출평가의 과정을 거쳐 개발된 곡선식의 적정성 검토를 실시하였다.

• Korean Journal of Environment and Ecology
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• v.23 no.2
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• pp.194-207
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• 2009

The study is to suggest a management method for improvement of natural and cultural landscape of Hwayang valley which is degraded in Songnisan National Park. It was carried out to study original shape of landscape of it and analyse nine major properties of Hoayang Gugok, based on old literatures. The landscape of Gugok was composed of rocks and small ponds, Pinus densiflora community and most of them were degraded by the situation of covered rocks by growth of vegetation, destructed small ponds by sedimented sands and degradation of natural landscape by artificial forest. Vegetation landscape of artificial forest composed of Populus tomentiglandulosa, Robinia pseudo-acacia, Pinus koraiensis in periphery of the valley was not matched with natural landscape. The goal of landscape management was established to conserve natural and cultural landscape in Joseon Dynasty. For this, It was needed to protect landscape values of gugok through the management of vegetation and visitors. In addition, it was required to provide opportunity to easily access to the landscape of Gugok. As a management method of vegetation, it was suggested to maintain P. densiflora community and to restore artificial forest to natural forest through the density management.

• Korean Journal of Remote Sensing
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• v.39 no.6_1
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• pp.1427-1435
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• 2023

Vegetation indices based on selected wavelength reflectance measurements are used to represent crop growth and physiological conditions. However, the anisotropic properties of the crop canopy surface can govern spectral reflectance and vegetation indices. In this study, we applied an ensemble of bidirectional reflectance distribution function (BRDF) models to high-resolution Sentinel-2 satellite imagery and compared the differences between correction results before and after reflectance. In the red and near-infrared (NIR) band reflectance images, BRDF-corrected outlier values appeared in certain urban and paddy fields of farmland areas and forest shadow areas. These effects were equally observed when calculating the normalized difference vegetation index (NDVI) and 2-band enhanced vegetation index (EVI2). Furthermore, the outlier values in corrected NIR band were shown in pixels shadowed by mountain terrain. These results are expected to contribute to the development and improvement of BRDF models in high-resolution satellite images.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.4 no.4
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• pp.25-35
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• 2001

This study aims to find out the growth characteristics of riparian plants on the artificial floating islands (AFI). Three types of experiments were performed. The vegetation growth were compared by the plant-supporting materials; natural cotton mat, coir mat on the AFI or in the water, and natural soil at the waterfront. Major findings are; 1. The survival rate of riparian plants was 100% on both coir-mat and cotton-matislands, which implies that we may substitute cheaper cotton for expensive coir-mat. 2. Both natural cotton mat and coir mat were good for the growth of plants. Especially, the natural cotton mat was good for Sparganium stoloniferum and Miscanthus sacchariflorus, and the coir mat was good for Typha latifolia. 3. The growth rate of stem and root showed difference between the stem-removed plants and stem-remaining plants. As a whole, the growth rate of stem-removed plants was bigger than the one of stem-remaining plants. 4. The growth rate of plants showed difference between those grown on the AFI and those grown in the water. The growth rate of plant on the AFI was bigger than the one in the water. 5. The growth rate of plants on the AFI was bigger than the one on the natural soil at the waterfront.

• Journal of Korean Society of Forest Science
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• v.100 no.4
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• pp.558-564
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• 2011

This study was conducted to evaluate the effects of early revegetation by analyzing the characteristics of germination and growth of Lespedeza cyrtobotrya using boring technique in rock slopes. After making up a growing basis of approximately 20 cm depth and 10 cm diameter by using a boring machine, the surface of rock slopes was planted with vegetation-plant. The number of germinating populations by soil media was 23 in H.s, 22 in T.s, 12 in M.s, and 1 in M.g.s. The germination rate (%) by soil media was 19.2% in H.s, 18.3% in T.s, 10.0% in M.s and 0.8% in M.g.s. In monthly changes of growth rate, the aspect was northwest direction, the soil media was M.s, and the treatment was microorganism plot. The main factors affecting survivorship and growth of population were soil media and treatment plot. The interaction between each factor had a good effects in bearing ${\times}$ soil media, bearing ${\times}$ treatment plot, soil media ${\times}$ treatment plot. but, it is recommended that the mulching of vegetation plant is highly needed to help the germination of seed and growth of vegetation because of loss of seed and soil media occurred due to rainfall. Therefore, The result suggests that the revegetation technique using boring in rock slope was very efficient in respect of the early revegetation and the landscape.

• Journal of Korean Society of Forest Science
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• v.107 no.1
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• pp.25-34
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• 2018

This study was performed to discover the comparison of the understory species composition and the growth velocity of the regeneration seedlings in Pinus densiflora forests being managed by the seed-tree method from 2008 year. The investigation site located in Bonghwa, Gyeongsangbuk-do province was established by eighteen quadrats such as six control ones, six slope ones and 6 concave ones, in which we carried out the vegetation survey and measured annual height growth of each seedlings. As a result of vegetation analysis, the understory vegetation of the seed-tree forest area was mainly composed of shrub plants such as Lespedeza bicolor, Zanthoxylum schinifolium, Securinega suffruticosa, Lespedeza maximowiczii and Stephanandra incisa, herb plants such as Miscanthus sinensis var. purpurascens, Carex humilis var. nana, Spodiopogon sibiricus and Artemisia keiskeana, and vine plants such as Pueraria lobata, Smilax sieboldii, Dioscorea batatas, Actinidia arguta, Vitis amurensis and Rubus crataegifolius. Especially, the vine plants were relatively more imported to the concave site than the control site and the slope site. As a result of measurement of growth velocity, the seedlings of the Pinus densiflora appeared to be 3,175 trees/ha for the non-suppressed trees and 7,842 trees/ha for the suppressed trees. In cases of the concave site, individuals of seedlings were much lower than those on the slope site, probably due to the competition effects of vine plants. Consideringly, silvicultural practices for clearing the vine plants should be inevitably accompanied. Also, the growth velocity of the suppressed and non-suppressed trees has been constantly increasing, those of the non-suppressed trees much higher than the suppressed trees. This represents that the seedlings grow rapidly after the suppressed period with competition to the surrounding plants. Therefore, specific practices such as blush control and vine clear should be carried out at the beginning stage of regeneration in the seed-tree stand.