• Title/Summary/Keyword: Vegetation condition

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Suggestion of Estimating Method for Net Primary Production in the Geum River Basin Using NDVI (정규화식생지수를 이용한 금강유역의 순일차생산량 추정방법의 제안)

  • Shin, Shachul;Beak, Sungcheol
    • Journal of the Korean GEO-environmental Society
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    • v.9 no.6
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    • pp.43-51
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    • 2008
  • This study is to evaluate the NPP (Net Primary Production) distribution in the Geum River basin from NOAA/AVHRR satellite imagery data. It is supposed that the natural vegetation condition and the NPP has the linear relationship. The NPP from natural vegetation increases proportional to the annual net radiation (Rn), where radiative dryness index (RDI) is a proportional constant connecting net radiation to NPP. Normalized Difference Vegetation Index (NDVI) is used for monitoring vegetation change, and iNDVI (integrated NDVI) for annual analysis. The iNDVI has a close relation to Rn and NPP, which can be used effectively for estimating NPP distribution of where the meteorological data is unavailable. The purpose of this study is to propose a simple method to get NPP in the Geum river basin.

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Changes of Zooplankton Community in an Artificial Vegetation Island of Lake Paldang (팔당호에서 인공 수초재배섬 설치에 따른 동물플랑크톤 군집 변화)

  • You, Kyung-A;Park, Hae-Kyung;Byeon, Myeong-Seop;Jeon, Nam-Hui;Choi, Myung-Jae;Yun, Seok-Hwan;Kong, Dong-Soo
    • Journal of Korean Society on Water Environment
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    • v.23 no.3
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    • pp.339-347
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    • 2007
  • Zooplankton community dynamics were studied after establishment of an artificial vegetation island (AVI) in Lake Paldang, from April 2005 to November 2006. There were distinct seasonal and inter-annual changes of total zooplankton abundance at the survey site. Total zooplankton abundance rapidly increased in spring and fall, while it remained low throughout winter. During summer, the dynamics of zooplankton community seemed to be largely affected by hydrological parameters such as, precipitation and inflow. Total zooplankton abundance and biomass below AVI was much higher than that of pelagic zone (L1) in Lake Paldang. Copepoda and cladocera represented the main bulk of the zooplankton community from summer to fall at the both sites. Copepods were more dominant at AVI area, while cladocera were more dominant at pelagic zone (L1). Water quality, prey and habitat condition, species competition between zooplankton seemed to play important roles in dominance of the copepoda and cladocera in zooplankton community at AVI area. Our results conclude that artificial vegetation island provide the stable habitat and besides phytoplankton, diverse food to zooplankton, and consequently influence the diversity and richness of zooplankton community.

Use Pattern and Impacts on Environmental Deteriorations on and around Trails in Chuwangsan National Park (주왕산국립공원 등산로의 이용패턴 및 주변환경훼손에 대한 이용영향)

  • 권태호;오구균;이준우
    • Korean Journal of Environment and Ecology
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    • v.8 no.2
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    • pp.167-176
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    • 1995
  • Autumn visitors to Chuwangsan National Park was more than summer's. About 89% of total visitors used main trail but approximately 35% visited to the Third Falls. The entire width, bare width, maximum depth and slope of trail as the trail condition surveyed at the total of 103 points were significantly greater on the more heavily-used trail. Trail conditons of rock-exposed, root-exposed, deepening points as the deterioration types of trail were significantly different from those of non-deteriorated points. According to the topographic position of trail, severe difference of dominant trees in the edge vegetation was found and Lespedeza maximowiczii, Rhododendron yedoense and Fraxinus sieboldana were dominant in shrub layer of trail edge vegetation. The crown coverage, number of species and individuals of shrub layer in edge vegetation were generally higher than those in the other national parks with more heavily-used trail.

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Estimation of Net Primary Production for Nakdong River Basin using Vegetation Index (식생지수를 이용한 낙동강유역의 순일차생산량 산정)

  • Shin, Shachul;Kwon, Giryang
    • Journal of the Korean GEO-environmental Society
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    • v.15 no.10
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    • pp.35-42
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    • 2014
  • This study is to evaluate Net Primary Production (NPP) using NDVI calculated by MODIS in the Nakdong river basin. This study is based on the method of using the fact that NPP is proportional to natural vegetation condition. This method is different from existing one, using remote sensed data. It is known that NPP of natural vegetation is proportional to the absorbed amount of visible light that is proportional to NDVI. Therefore, estimating NPP by using NDVI is one of the most highly useful methods. This method can be used in a wide range of areas where vegetation data can not be obtained easily or where there is not enough meterological data. This study proposes the estimating method for NPP that is based upon NDVI, which is obtained by MODIS, and verifies by comparing the NPP with empirical results.

Relationships between Forest Understory Habitat and Small Rodents in Mt. Chirisan National Park (지리산(智異山) 지역(地域)에서 산림(山林) 하층(下層)의 서식환경(棲息環境)과 소형(小型) 설치류(齧齒類)와의 관계(關係))

  • Rhim, Shin-Jae;Lee, Woo-Shin
    • Journal of Korean Society of Forest Science
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    • v.90 no.3
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    • pp.236-241
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    • 2001
  • This study was conducted to clarify the relationship between forest understory habitat and small rodents in the study sites of 500m, 800m and 1,100m a. s. l. of 6 areas in Mt. Chirisan National Park from July 1997 to August 1998. Coverage of understory vegetation and depth of litter layer were increased as the increase of altitude. Seventy seven individuals of Apodemus agrarius, A. peninsulae and Eothenomys regulus were captured in all study areas. There were significantly correlations among coverage of understory vegetation, depth of litter layer and number of captured small rodents. Increase of understory vegetation coverage and litter layer would provide the proper habitat condition for small rodents.

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The Study on the Evaluation of Environment Function at Small Stream - In the Case of Hongdong Stream in Hongsung-gun - (농촌지역 소하천의 환경성 평가 연구 - 홍성군 홍동천을 사례로 -)

  • Kang, Banghun;Son, Jin-Kwan
    • Journal of the Korean Society of Environmental Restoration Technology
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    • v.14 no.5
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    • pp.81-101
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    • 2011
  • This study was conducted to understand the environmental and ecological function of habitat through evaluation of water environment, soil environment, vegetation characteristics, macro-invertebrate characteristics, and visual habits environment evaluation (SVAP) in Hongdong stream located in Hongseong-Gun, Chungnam Province, and hereafter to utilize the results for the habits reconstruction and improvement project. As the results of water quality analysis, BOD, COD, T-P was almost below the standard quality from upper stream to down stream. The construction of small reservoir, wetland and water purification facility, and the management of non-point pollution are proposed to improve these problems. The soil texture was sandy soil, which is unfitted with vegetation development. The construction of shallows and bogs, and induction of soil sedimentation and biotope formation are proposed to improve these problems. In the plant flora, total 90 kinds were observed with 81 species and nine varieties in total 36 families and 85 genera, and the naturalization rate was higher at down area than upper area. As the results of macro-invertebrate fauna survey, total 26 species and 297 individuals in 20 families and 22 genera were collected. Peltodytes sinensis, Chironomidae sp., and Culicidae sp., which are observed at polluted environment, were collected as dominant species. An appropriate vegetation management party idea is necessary, and it is done an idea in consideration of the soil and a physical characteristic. Visual habits environment evaluation (SVAP) result was mostly determined with below normal (Fair) grade. Pollution source interception, purification pond establishment, and various bog establishment are proposed to improve these problems. With the above results, the ecological environment was determined with bad condition, and the improvement of biotope was urgently needed through sustainable monitoring and management of streams habitat in rural area.

A study on thermal simulation for extensive green roof system using a plant canopy model (식생캐노피모델을 통한 저관리 조방형 옥상녹화시스템의 열해석 전산모의에 관한 연구)

  • Kim, Tae Han
    • Journal of the Korean Society of Environmental Restoration Technology
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    • v.15 no.2
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    • pp.137-147
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    • 2012
  • GRS is an effective urban ecology restoration technique that can manage a variety of environmental functions such as ecological restoration, rainwater spill control and island heat effect from a low-impact development standpoint that can be utilized in new construction and retrofits. Recently, quantitative evaluation studies, both domestic and abroad, in the areas related to these functions, including near-earth surface climate phenomenon, heavy rainwater regulation, thermal environment of buildings, have been actively underway, and there is a trend to standardize in the form of technological standards. In particular, centered on the advanced European countries, studies of standardizing the specific insulation capability of buildings with green system that comprehensively includes the green roof, from the perspective of replacing the exterior materials of existing buildings, are in progress. The limitation of related studies in the difficulties associated with deriving results that reflect material characteristics of continuously evolving systems due in part to not having sufficiently considered the main components of green system, mechanisms of vegetation, soils. This study attempts to derive, through EnergyPlus, the effects that the vegetation-related indicators such as vegetation height, FCV, etc. have on building energy load, by interpreting vegetation and soil mechanisms through plant canopy model and using an ecological standard indicator LAI that represent the condition of plant growth. Through this, the interpretations that assume green roof system as simple heat insulation will be complemented and a more practical building energy performance evaluation method that reflects numerical methods for heat fluxes phenomena that occur between ecology restoration systems comprised of plants and soil and the ambient space.

Suggestion of Simple Method to Estimate Evapotranspiration Using Vegetation and Temperature Information (식생 및 기온정보를 조합한 증발산량 산정을 위한 간편법 제안)

  • Shin, Sha-Chul;Hwang, Man-Ha;Ko, Ick-Hwan;Lee, Sang-Jin
    • Journal of Korea Water Resources Association
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    • v.39 no.4 s.165
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    • pp.363-372
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    • 2006
  • Many methods have been used to estimate evapotranspiration. However, there is little information about the evapotranspiration from river basins with complicated topographies and variable land use. Remote sensing technique is a probable means to estimate distribution of the evapotranspiration in connection with regional characteristics of vegetation and landuse. The evapotranspiration not only depends on meteorological circumstances but also on the condition of the vegetation. The latter effect can be expressed in terms of NDVI(Normalized Difference Vegetation Index) obtained by NOAA/AVHRR datasets. In this paper, a simple method to estimate evapotranspiration of the Keum river basin is proposed based on NDVI and temperature data.

Adaptive Reconstruction of NDVI Image Time Series for Monitoring Vegetation Changes (지표면 식생 변화 감시를 위한 NDVI 영상자료 시계열 시리즈의 적응 재구축)

  • Lee, Sang-Hoon
    • Korean Journal of Remote Sensing
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    • v.25 no.2
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    • pp.95-105
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    • 2009
  • Irregular temporal sampling is a common feature of geophysical and biological time series in remote sensing. This study proposes an on-line system for reconstructing observation image series including bad or missing observation that result from mechanical problems or sensing environmental condition. The surface parameters associated with the land are usually dependent on the climate, and many physical processes that are displayed in the image sensed from the land then exhibit temporal variation with seasonal periodicity. An adaptive feedback system proposed in this study reconstructs a sequence of images remotely sensed from the land surface having the physical processes with seasonal periodicity. The harmonic model is used to track seasonal variation through time, and a Gibbs random field (GRF) is used to represent the spatial dependency of digital image processes. In this study, the Normalized Difference Vegetation Index (NDVI) image was computed for one week composites of the Advanced Very High Resolution Radiometer (AVHRR) imagery over the Korean peninsula, and the adaptive reconstruction of harmonic model was then applied to the NDVI time series from 1996 to 2000 for tracking changes on the ground vegetation. The results show that the adaptive approach is potentially very effective for continuously monitoring changes on near-real time.

Application of VIIRS land products for agricultural drought monitoring (농업가뭄 모니터링을 위한 VIIRS 센서 지표산출물 적용성 분석)

  • Sur, Chanyang;Nam, Won-Ho
    • Journal of Korea Water Resources Association
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    • v.56 no.11
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    • pp.729-735
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    • 2023
  • The Moderate resolution Imaging Spectroradiometer (MODIS) is a multispectral sensor that has been actively researched in various fields using diverse land and atmospheric products. MODIS was first launched over 20 years ago, and the demand for novel sensors that can produce data comparable to that obtained using MODIS has continuously increased. In this study, land products obtained using the Visible Infrared Imaging Radiometer Suite (VIIRS) of the Suomi National Polar-orbiting Partnership (Suomi NPP) satellite launched in 2011 were introduced, including land surface temperature and vegetation indices such as the normalized difference vegetation index and enhanced vegetation index. These land products were compared with existing data obtained using MODIS to verify their local applicability in South Korea. Based on spatiotemporal monitoring of an extreme drought period in South Korea and the application of VIIRS land products, our results indicate that VIIRS can effectively replace MODIS multispectral sensors for agricultural drought monitoring.