• 제목/요약/키워드: Canopy Model

검색결과 218건 처리시간 0.028초

SWAT 모형을 이용한 기후와 식생 활력도 변화가 수자원에 미치는 영향 평가 (Assessment of Climate and Vegetation Canopy Change Impacts on Water Resources using SWAT Model)

  • 박민지;신형진;박종윤;강부식;김성준
    • 한국농공학회논문집
    • /
    • 제51권5호
    • /
    • pp.25-34
    • /
    • 2009
  • The objective of this study is to evaluate the future potential climate and vegetation canopy change impact on a dam watershed hydrology. A $6,661.5\;km^2$ dam watershed, the part of Han-river basin which has the watershed outlet at Chungju dam was selected. The SWAT model was calibrated and verified using 9 year and another 7 year daily dam inflow data. The Nash-Sutcliffe model efficiency ranged from 0.43 to 0.91. The Canadian Centre for Climate Modelling and Analysis (CCCma) Coupled Global Climate Model3 (CGCM3) data based on Intergovernmental Panel on Climate Change (IPCC) SRES (Special Report Emission Scenarios) B1 scenario was adopted for future climate condition and the data were downscaled by artificial neural network method. The future vegetation canopy condition was predicted by using nonlinear regression between monthly LAI (Leaf Area Index) of each land cover from MODIS satellite image and monthly mean temperature was accomplished. The future watershed mean temperatures of 2100 increased by $2.0^{\circ}C$, and the precipitation increased by 20.4 % based on 2001 data. The vegetation canopy prediction results showed that the 2100 year LAI of deciduous, evergreen and mixed on April increased 57.1 %, 15.5 %, and 62.5% respectively. The 2100 evapotranspiration, dam inflow, soil moisture content and groundwater recharge increased 10.2 %, 38.1 %, 16.6 %, and 118.9 % respectively. The consideration of future vegetation canopy affected up to 3.0%, 1.3%, 4.2%, and 3.6% respectively for each component.

도시림 식생의 생태적 특성과 복원모델 (Ecological Characteristics and Restoration Model of Vegetation in the Urban Forest)

  • 김석규;주경중;남정칠;박승범
    • 한국환경복원기술학회지
    • /
    • 제13권2호
    • /
    • pp.80-94
    • /
    • 2010
  • The purpose of this study is suggest to restoration model of Pinus thunbergii in Saha-gu, Busan. The result of this study is summarized as follows. As the results of this study, vegetation restoration model is presented by separating community planting and edge planting. In community planting, as a group of canopy, there are 6 species; Pinus thunbergii, Quercus acutissima, Quercus dentata, Quercus serrata, Quercus alienna, Quercus variabilis. As a group of understory, there are 5 species; Platycarya strobilacea, Prunus sargentii, Styrax japonica, Eurya japonica, Morus bombycis. Also as a group of shrub, there were 15 kinds of species; Ulmus pavifolia, Ulmus davidiana, Lindera obtusiloba, Elaeagnus macrophylla, Mallotus japonicus, Ligustrum obtusifolium, Sorbus alnifolia, Rhus trichocarpa, Zanthoxylum schinifolium, Rosa wichuraiana, Rhus chinensis, Viburnum erosum, Rhododendron mucronulatum, Rhododendron yedoense, Indigofera pseudotinctoria. And as a group of edge vegetation, there were 10 kinds of species; Japanese Angelica, Symplocos chinensis, Pittosporum tobira, Lespedeza maximowiczii, Lespedeza bicolor, Rubus coreanus, Rubus idaeus, Vitis thunbergii, Ampelopsis brevipedunculata, Rosa multiflora. Vegetation restoration models of Pinus thunbergii community were calculated the units $400m^2$ for the average populations of the woody layer is 24 in canopy layer, 35 in understory layer, 410 in shrub layer, 34% herbaceous layer ground cover. And the average of breast-high area and canopy area is $10,852cm^2$ in canopy layer, in understory layer $1,546cm^2$, in shrub layer $1,158,660cm^2$. The shortest distance between trees is calculated as 2.0m in canopy layer, 1.9m in understory layer.

도시공원 구조 및 식생 조건에 따른 조류 종다양성 분석 - 천안시 26개 도시공원을 대상으로 - (Analysis of Bird Species Diversity Response to Structural Conditions of Urban Park - Focused on 26 Urban Parks in Cheonan City -)

  • 송원경
    • 한국환경복원기술학회지
    • /
    • 제18권3호
    • /
    • pp.65-77
    • /
    • 2015
  • The urban park has important functions as a habitat for wildlife as well as open space of rest and community for people. This study was carried out to find what factors of structure and vegetation of urban parks could affect forest bird species diversity in Cheonan city. The study surveyed bird and vegetation species in 26 urban parks, Cheonan city. A correlation analysis and multiple linear regressions were performed to test whether habitat structure and vegetation were the major correlate with species diversity. The results showed the Dujeong park was the most high bird species diversity (H' = 2.13), and the Dujeong-8 park (H' = 2.02) and the Cheongsa park (H' = 1.73) were considerably higher than the other urban parks. The variables that were strongly correlated with bird species diversity were park area, number of subtree species, canopy of shrub, number of shrub species, shape index, canopy of subtree, canopy of tree, and impervious surface ratio. The regression of bird species diversity against the environmental variables showed that 3 variables of park area, canopy of subtree, and canopy of tree were included in the best model. Model variable selection was broadly similar for the 5 optimal models. It means park area and multi-layer vegetation were the most consistent and significant predictor of bird species diversity, because urban parks were isolated by built-up areas. Especially the subtree coverage that provides shelter and food for forest birds was an important variable. Therefore, to make parks circular-shaped and abundant multi-layer vegetation, which could be a buffer to external disturbances and improve the quality of habitats, may be used to enhance species diversity in creation and management of urban parks.

생화학 및 생물리 모수들의 도출과 생권 모형(SiB2)에의 적용 (Derivation of Biochemical and Biophysical Parameters and Their Application to the Simple Biosphere Model (SiB2))

  • 채남이;김준
    • 한국농림기상학회지
    • /
    • 제1권1호
    • /
    • pp.52-59
    • /
    • 1999
  • Vegetation canopy plays an important role in $CO_2$/$H_2$O exchange between the biosphere and the atmosphere by controlling leaf stomata. In this study, rice (Oryza sativa L.), a staple crop in Asia was investigated to formulate its single leaf model of photosynthesis and stomatal conductance. Photosynthesis and stomatal conductance were measured with a portable infrared gas analyzer system. Other plant and meteorological variables were also measured. To evaluate empirical constants in this biochemical leaf model, nonlinear least squares technique was used. The maximum catalytic activity of enzyme and the maximum rate of electron transport were $ 100\mu$$m^{-2}$ $s^{-1}$ and $140 \mu$㏖ m$^{-2}$ s$^{-1}$ (@ 35$^{\circ}C$), respectively. The empirical constants, m and b, associated with stomatal conductance model were 9.7 and $0.06 m^{-2}$ $s^{-1}$ , respectively. On a leaf scale, agreements between the modeled and the measured values of photosynthesis and stomatal conductance were on average within 20%, and the simulation of diurnal variation was also satisfactory On a canopy scale, the Simple Biosphere model(SiB2) was tested using the derived parameters. The modeled energy fluxes were compared against the micrometeorologically measured fluxes over a rice canopy. Agreements between the modeled and the measured values of net radiation, sensible heat and latent heat fluxes, and $CO_2$ flux (i.e., net canopy photosynthesis) were on average within 25%.

  • PDF

하늘시계지수 비교 및 도시기온 상관성 연구: 강남 선정릉지역을 중심으로 (A Study on a Comparison of Sky View Factors and a Correlation with Air Temperature in the City)

  • 이채연;신이레;안승만
    • 대기
    • /
    • 제27권4호
    • /
    • pp.483-498
    • /
    • 2017
  • Sky view factor can quantify the influence of complex obstructions. This study aims to evaluate the best available SVF method that represents an urban thermal condition with land cover in complex city of Korea and also to quantify a correlation between SVF and mean air temperature; the results are as follows. First, three SVF methods comparison result shows that urban thermal study should consider forest canopy induced effects because the forest canopy test (on/off) on SVF reveals significant difference range (0.8, between maximum value and minimum value) in comparison with the range (0.1~0.3) of SVFs (Fisheye, SOLWEIG and 3DPC) difference. The significance is bigger as a forest cover proportion become larger. Second, R-square between SVF methods and urban local mean air temperature seems more reliable at night than a day. And as the value of SVF increased, it showed a positive slope in summer day and a negative slope in winter night. In the SVF calculation method, Fisheye SVF, which is the observed value, is close to the 3DPC SVF, but the grid-based SWG SVF is higher in correlation with the temperature. However, both urban climate monitoring and model/analysis study need more development because of the different between SVF and mean air temperature correlation results in the summer night period, which imply other major factors such as cooling air by the forest canopy, warming air by anthropogenic heat emitted from fuel oil combustion and so forth.

야외조건하(野外條件下)에서 독일가문비(Picea abies Karst) 침엽(針葉)의 순(純) 광합성률(光合成率)의 단기(短期) 변화(變化)에 대한 실험적(實驗的) 연구(硏究) (Experimental Studies of the Short-Term Fluctuations of Net Photosynthesis Rate of Norway Spruce Needles under Field Conditions)

  • ;;진현오;주영특;정동준
    • 한국산림과학회지
    • /
    • 제88권1호
    • /
    • pp.38-46
    • /
    • 1999
  • 독일 중부(Solling Hills)의 가문비림 임관의 구조적인 수분증산 통도특성은 LE와 H의 유동량으로 측정되고, 1996년 6월중 재배열된 Penman-Monteith 식을 이용하여 SVAT 모형을 설계하여 도출하였다. 또한 SLODSVAT 모형을 통한 전체 임관 내 각 침엽의 연속적인 수분통도성을 평가하여 임관기공의 통도성을 비교하였다. 이와 같은 결과에서 나온 임관 표면 통도성과 유동량을 설계하고, SLODSVAT 모형에 의해 설계된 기공 통도성 사이에서 중요한 차이점을 알 수 있었다. 이 차이점은 산림 임관의 범위내에 빗물리적인 요소에 의해 영향을 받았음을 알 수 있으며, 일반적으로 임관 표변의 통도성은 전체 측정 기간 동안 임관 기공 전도력보다 크게 나타났다. 또한 산림의 전체 증발산량에 대한 하층부의 공헌도는 작았고, 임관의 복사에너지 균형에 의존하지는 않는 것으로 나타났다. 하층부 증발산량의 기각은 독일 가문비림에 대한 임관 표면 전도력의 과대 평가로서 나타난 결과이다.

  • PDF

Vegetation Canopy의 접지층 환경에 대한 열적 영향 제2부 : 벼 식피층 관측 (On the Thermal Effect of Vegetation Canopy to the Surface Sublayer Environment)

  • 진병화;황수진
    • 한국환경과학회지
    • /
    • 제8권2호
    • /
    • pp.151-154
    • /
    • 1999
  • To verify the accuracy of the numerical experiment of Part I, measurements at the matured rice canopy located around Junam reservoir were performed at August 14, 1995. According to the measured data, the foliage temperature recorded the highest value, and the ground temperature was the lowest around noon, and these results coincided with those of the numerical experiment using the combined model of Part I. From the estimation using measured data, the maximum value of the latent heat flux was 380$Wm^2$, the highest value among energy balance terms, and the energy redistribution ratio of the latent heat flux was averaged as 0.5, the highest values among redistribution ratios. These results are the same as those of the numerical experiment in tendency, but they reveals a little lower in the absolute values than those from the numerical experiment.

  • PDF

녹지대 분포가 도시 지역의 소기후에 미치는 영향 (On the Impacts to the Loca l Climate Change of Urban Area due to the Vegetation Canopy)

  • 진병화;변희룡
    • 한국환경과학회지
    • /
    • 제9권2호
    • /
    • pp.101-108
    • /
    • 2000
  • Through numerical experiment using simplified OSU-1D PBL(Oregon State University One-Dimensional Planetary Boundary Layer) model and field measurement, we studied the impacts of vegetation canopy on heat island that was one of the characteristics of local climaate in urban area. it was found that if the fraction of vegetation was extended by 10 percent, the maximum air temperature and the maximum ground temperature can come down about 0.9${\circ}C$, 2.3${\circ}C$, respectively. Even though the field measurement was done under a little unstable atmospheric condition, the canopy air temperature was lower in the daytime, and higher at night than the air and ground temperature. This result suggests that the extention of vegetation canopy can bring about more pleasant local climate by causing the oasis, the shade and the blanket effect.

  • PDF

도로기상정보체계 활성화를 위한 노면온도예측 모형 개발 (A Road Surface Temperature Prediction Modeling for Road Weather Information System)

  • 양충헌;박문수;윤덕근
    • 대한교통학회지
    • /
    • 제29권2호
    • /
    • pp.123-131
    • /
    • 2011
  • 본 연구에서는 지표면과 대기사이의 열-에너지 균형원리를 이용한 노면온도예측모형을 개발하였다. 본 연구에서 개발된 노면온도예측모형은 두 가지 모듈로 구성되는데 Canopy 1은 지표면과 대기 간의 열 교환을 묘사하기 위한 것이고, Canopy 2는 열에너지 교환 과정에서 포장체 특성을 반영하기 위한 것이다. 모형 수행에 필요한 다양한 입력변수는 기상청으로부터 수집하였다. 개발된 모형의 성능을 평가하기 위해 청원-상주 간 고속도로 상 문의교 지점에 설치된 접촉식 노면온도측정센서로부터 수집한 노면온도자료와 모형 수행을 통해 나온 결과 값을 비교 하였다. 이러한 비교는 동절기(12월)와 동절기 외 기간(10월)에 걸쳐 수행되었다. 비교 결과, 두 온도의 평균오차 값이 ${\pm}2^{\circ}C$ 범위 내에 있어, 모형의 성능이 매우 우수한 것으로 판단된다. 이러한 연구는 동절기 도로관리에 다양하게 사용될 것으로 사료되고, 특히 도로 기상정보체계 운영에 핵심이 되는 노면온도 예측 알고리즘으로 사용될 수 있는 기초 연구가 될 것이다.

Calculation of Tree Height and Canopy Crown from Drone Images Using Segmentation

  • Lim, Ye Seul;La, Phu Hien;Park, Jong Soo;Lee, Mi Hee;Pyeon, Mu Wook;Kim, Jee-In
    • 한국측량학회지
    • /
    • 제33권6호
    • /
    • pp.605-614
    • /
    • 2015
  • Drone imaging, which is more cost-effective and controllable compared to airborne LiDAR, requires a low-cost camera and is used for capturing color images. From the overlapped color images, we produced two high-resolution digital surface models over different test areas. After segmentation, we performed tree identification according to the method proposed by , and computed the tree height and the canopy crown size. Compared with the field measurements, the computed results for the tree height in test area 1 (coniferous trees) were found to be accurate, while the results in test area 2 (deciduous coniferous trees) were found to be underestimated. The RMSE of the tree height was 0.84 m, and the width of the canopy crown was 1.51 m in test area 1. Further, the RMSE of the tree height was 2.45 m, and the width of the canopy crown was 1.53 m in test area 2. The experiment results validated the use of drone images for the extraction of a tree structure.