• 대한원격탐사학회:학술대회논문집
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• 대한원격탐사학회 1999년도 Proceedings of International Symposium on Remote Sensing
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• pp.429-432
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• 1999

Vegetation cover classification is examined based on a time series NOAA/AVHRR data. Time series data analysis methods including Fourier transform, Auto-Regressive (AR) model and temporal signature similarity matching are developed to extract phenological features of vegetation from a time series NDVI data from NOAA/AVHRR and to classify vegetation types. In the Fourier transform method, typical three spectral components expressing the phenological features of vegetation are selected for classification, and also in the AR model method AR coefficients are selected. In the temporal signature similarity matching method a new index evaluating the similarity of temporal pattern of the NDVI is introduced for classification.

• Spatial Information Research
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• 제20권4호
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• pp.47-55
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• 2012

정규식생지수(NDVI)는 식생자원을 모니터링할 수 있도록 설계된 식생지수(VI-Vegetation Index) 중 하나로 여러 응용 분야에서 가장 많이 사용되고 있는 지수이다. 산림 분야에서도 NDVI가 많이 활용되고 있는데 본 논문에서는 산림 변화 모니터링을 위해 MODIS NDVI를 활용하는 방법론이 연구되었다. 특정 시점을 기준으로 NDVI 값을 비교 및 분류하여 변화를 탐지하는 방법은 기계나 기상상태의 영향으로 자료의 정확성이 떨어질 수 있고 장기적인 변화를 탐지하는데도 어려움이 있다. 이러한 점을 고려하여 본 논문에서는 하모닉 모형을 이용하여 NDVI 시계열 자료를 통해 NDVI 패턴을 고려하는 방법론을 제시하였다. 먼저 하모닉 모형을 적용하여 미관측 자료나 자료의 오류를 보정한 NDVI 시계열 자료를 재구축하고 추정된 하모닉 요소의 모수를 기준으로 장기적 패턴을 통해 식생의 변화를 모니터링할 수 있다. 제안된 방법은 한반도 지역의 2009년 8월 21일부터 2011년 9월 6일까지 총 49개의 MODIS NDVI 시계열 자료에 적용하여 모형의 유용성을 입증하였다.

• The Korean Journal of Ecology
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• 제21권6호
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• pp.791-797
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• 1998

An attempt to clarify the landscape structure of urban areas was carried out on Mt. Hwangryung located in the center of Pusan, southern Korea. By means of aerial photographs and field survey, a vegetation map including land-use pattern was made. Landscape structure was described by analyzing the vegetation map. Landscape element types were classified into secondary forest, introduced plantation, and other elements including urbanized area. almus firma and Pinus thunbergii communities, introduced plantation elements, formed matrix and some secondary forest elements and the other artificial plantations of small scale tended to distribute as small patches in such matrix. The number of patches per unit area in secondary forest elements was more than that in introduced plantation element. The result on patech size was vice versa. As the results of landscape ecological analyses, it was estimated that differentiation of patches recognized in community level would be related to artificial interference and those in sub-communities levels to natural process such as progression of succession. On the other hand, restoration plans in viewpoints of restoration and landscape ecology were suggested to improve ecological quality of Mt. hwangryung.

• The Korean Journal of Ecology
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• 제17권2호
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• pp.185-201
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• 1994

The Quercus mongolica forest vegetation of Mt. Myongji was classified into two communities including four subunit communities and one typical subunit community by the Z-M method as follows: Acer pseudo-sieboldianum-Quercus mongolica community group Quercus mongolica - Isodon excisus community Quercus mongolica - Styrax obassia community Quercus mongolica - Lespedeza bicolor subunit coummunity Quercus mongolica - Aconitum longecassidatum subunit community Quercus mongolica - Rhododendrom schlippenbachii subunit community Quercus mongolica - Cornus controversa subunit community Quercus mongolica - Styrax obassia typical subunit community Acer pseudo-sieboldianum - Quercus mongolica community group was distributed over the upper region of the altitude 400m, and the differential species in the community were Carex siderosticata, Sephanandra incisa, Tripterygium regelii, and Fraxinus rhynchophylla. The vegetation patterns for the slope and azimuth showed that the highest importance value for Quercus mongolica forest was observed on the broad subxeric area, and for Carpinus cordata and Acer pseudo-sieboldianum on the wet site, for Acer mono, Styrax obassia, Fraxinus rhynchophylla and Symplocos chinensis for. pilosa on the xeric site. The best habitat condition for Quercus mongolica was found at a subxeric site at the altitude of 700-900m on southern slope and that for Acer pseudo-sieboldianum at the 700-1100m on northern slope.

• 대한원격탐사학회지
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• 제22권3호
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• pp.175-182
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• 2006

Because of the phenological variation of vegetation growth in temperate region, it is often difficult to accurately assess the surface conditions of agricultural croplands, grasslands, and disturbed forests by multi-spectral remote sensor data. In particular, the spectral similarity between soil and dry vegetation has been a primary problem to correctly appraise the surface conditions during the non-growing seasons in temperature region. This study analyzes the spectral characteristics of the mixture of dry vegetation and soil. The reflectance spectra were obtained from laboratory spectroradiometer measurement (GER-2600) and from EO-1 Hyperion image data. The reflectance spectra of several samples having different level of dry vegetation fractions show similar pattern from both lab measurement and hyperspectral image. Red-edge near 700nm and shortwave IR near 2,200nm are more sensitive to the fraction of dry vegetation. The use of hyperspectral data would allow us for better separation between bare soils and other surfaces covered by dry vegetation during the leaf-off season.

• The Korean Journal of Ecology
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• 제12권2호
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• pp.109-122
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• 1989

The vegetation and landscape of Hokkaido were phytosociologically referred. The region of F a g e t e a c r e n a t a e on Hokkaido is divided into two types of deciduous broad-leaved forest: the oak (Quercus mongolica var. grosseserrata) forests mixed with conifers (mainly Abies sachalinensis) and the beech (Fagus crenata) forests of northernmost distribution in far-east Asia. The oak forests, which is dominated by Quercus mongolica var. grosseserrata in Japanse islands, seem to be developed from different climatic and edaphic conditions, especially in the amount and sharing pattern of precipitation in a year, and weak acid brown forest soil, volcanic ash soil and sandy soil. On the all-inclusive phytogeographical view-point, Hokkaido is situated at northernmost region of F a g e t e a c r e n a t a e (cool-temperate zone)neighboring with subarctic and subalpine vegetation, vegetation, but the evergreen broad-leaved forest (C a m e l l i e t e a j a p o n i c a e, warm-temperate zone) is abscent.

• 한국제4기학회지
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• 제22권2호
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• pp.6-11
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• 2008

Vegetation change reconstructed by pollen analysis is effective to clarify natural conditions such as climate and soil as well as intensity of human activity. Pollen analysis in Korea is difficult to obtain peaty soil sedimented by low relief geomorphollogically and formation age is usually confined to obtain information during young Holocene as well as little absolute age data. Isopollen map was constructed in order to analyze the change of vegetation environment time-spatially during Holocene based on the 30 data with age dated from 78 results from pollen analysis in Korea. The indicatives for vegetation environment were the main trees in Korea such as Alnus, Pinus, Quercus and AP/NAP during the periods of 6,000 y.BP, 4,000 y.BP, 3,000 y.BP, 2,000 y.BP, 1,000 y.BP. As a result, the regional time-spatial patterns of vegetation distribution appeared clearly on the isopollen map. The dominant vegetation stage was repeated in the different pattern e.g. the dominance between Alnus and Quercus at West Coast and between Pinus and Quercus at East Coast competitively.

• 한국산림과학회지
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• 제94권6호
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• pp.453-461
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• 2005

우리나라의 대표적인 황폐된 임지의 인공복원 성공지인 영일사방사업지를 대상으로 산림식생의 구성적 특성과 천이경향이 총 68개 조사구를 토대로 식물사회학적 방법과 매목조사법에 의하여 연구되었으며, 주요 사방조림목의 생장패턴이 연륜심 분석을 통하여 파악되었다. 이 지역의 식생형은 싸리-억새형과 사방오리-때죽나무형 등 2개 광역그룹으로 대별되었으며, 9개의 하위 식생단위가 유형화되었다. 상재도 패턴은 고상재도종(${\geq}IV$)은 2.6%에 불과하고 대부분의 종들이 저상재도종으로 생육분포하고 있었다. 식생천이경향은 대부분이 졸참나무림으로 변화될 것으로 판단되었다. 주요 사방조림목의 연평균 생장 폭은 수종별로 다소 차이가 있지만 곰솔과 리기다소나무 등 침엽수는 3.0~3.4 mm, 사방오리, 아까시나무, 물오리나무 등 활엽수는 4.3~4.9 mm로 나타났으며, 생장패턴은 수종에 관계없이 조림후 20~25년이 지나면서 급격한 생장감소를 보이고 있음을 알 수 있었다.

• 대한원격탐사학회:학술대회논문집
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• 대한원격탐사학회 2003년도 Proceedings of ACRS 2003 ISRS
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• pp.952-954
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• 2003

In this paper, we present the different characteristics of NDVI fluctuation pattern between irrigated and non-irrigated area in Suphanburi province, in Central Thailand. For non-irrigated rice cultivation area, there is a strong correlation between NDVI fluctuation and peak rainfall, while there is a lower correlation with irrigated area. In this study, the 'peak detector' classifier was developed to identify the area of non-irrigated and irrigated cropping and its cropping intensity (number of crops per year). This classifier was created based on cropping characteristics such as number of crops, time or planting period of each crop and its relationship with the peak of rainfall. The classified result showed good accuracy in identification irrigated and nonirrigated rice cultivation areas.

• 대한원격탐사학회지
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• 제21권5호
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• pp.383-392
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• 2005

Vegetation classes, especially grass and tree classes, are often confused in classification when conventional spectral pattern recognition techniques are used to classify urban areas. This paper reports on a study to improve the classification results by using an automated process of considering height information in separating urban vegetation classes, specifically tree and grass, using three-band, high-spatial resolution, digital aerial imagery. Height information was derived photogrammetrically from stereo pair imagery using cross correlation image matching to estimate differential parallax for vegetation pixels. A threshold value of differential parallax was used to assess whether the original class was correct. The average increase in overall accuracy for three test stereo pairs was $7.8\%$, and detailed examination showed that pixels reclassified as grass improved the overall accuracy more than pixels reclassified as tree. Visual examination and statistical accuracy assessment of four test areas showed improvement in vegetation classification with the increase in accuracy ranging from $3.7\%\;to\;18.1\%$. Vegetation classification can, in fact, be improved by adding height information to the classification procedure.