• 제목/요약/키워드: Vegetation coverage

검색결과 319건 처리시간 0.024초

Predicting Italian Ryegrass Productivity Using UAV-Derived GLI Vegetation Indices

  • Seung Hak Yang;Jeong Sung Jung;Ki Choon Choi
    • 한국초지조사료학회지
    • /
    • 제44권3호
    • /
    • pp.165-172
    • /
    • 2024
  • Italian ryegrass (IRG) has become a vital forage crop due to its increasing cultivation area and its role in enhancing forage self-sufficiency. However, its production is susceptible to environmental factors such as climate change and drought, necessitating precise yield prediction technologies. This study aimed to assess the growth characteristics of IRG and predict dry matter yield (DMY) using vegetation indices derived from unmanned aerial vehicle (UAV)-based remote sensing. The Green Leaf Index (GLI), normalized difference vegetation index (NDVI), normalized difference red edge (NDRE), and optimized soil-adjusted vegetation index (OSAVI) were employed to develop DMY estimation models. Among the indices, GLI demonstrated the highest correlation with DMY (R2 = 0.971). The results revealed that GLI-based UAV observations can serve as reliable tools for estimating forage yield under varying environmental conditions. Additionally, post-winter vegetation coverage in the study area was assessed using GLI, and 54% coverage was observed in March 2023. This study assesses that UAV-based remote sensing can provide high-precision predictions of crop yield, thus contributing to the stabilization of forage production under climate variability.

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) (Relationships between Forest Understory Habitat and Small Rodents in Mt. Chirisan National Park)

  • 임신재;이우신
    • 한국산림과학회지
    • /
    • 제90권3호
    • /
    • pp.236-241
    • /
    • 2001
  • 본 연구는 산림 하층의 환경특성과 설치류 서식밀도를 조사하여 산림생태계 내에서 소형 설치류와 산림 하층의 서식환경과의 관계를 파악하고자 1997년 7월부터 1998년 8월 사이에 지리산국립공원의 6개 지역에서 각각 해발고도 500m, 800m, 1,100m에 설정한 총 18개의 조사 지역에서 실시하였다. 해발고도가 높아짐에 따라 대부분의 지역에서 하층식생의 피도량과 유기물층의 깊이가 증가하는 것으로 나타났다. 소형 설치류의 포획결과 등줄쥐, 흰넓적다리붉은쥐, 대륙밭쥐 등 3종 77개체가 포획되었는데 각 지역별 포획 개체수는 하층식생의 피도량과 유기물층의 발달 정도와 밀접한 관련이 있는 것으로 나타났다. 토양내 하층식생의 발달로 인한 피도량의 증가와 유기물층의 발달은 소형 설치류에게 있어서 알맞은 서식환경을 제공해 주는 것으로 판단된다.

  • PDF

Maxent 모델을 이용한 양봉꿀벌의 서울시 수분 잠재환경 분석 (The Analysis of Pollination Potential Environment for Apis mellifera in Seoul Using Maxent Modeling Approach)

  • 김윤호;조용현;배양섭;김다윤
    • 한국환경복원기술학회지
    • /
    • 제23권4호
    • /
    • pp.85-96
    • /
    • 2020
  • The honeybee serves for most entomophilous flowers. They are a core species for maintaining the ecological system. Though the urban ecological system needs bees' mediation of pollination as well, we have little understanding on how the honeybee reacts to the physical environments of an urban city. This study is a basic research to enhance the potential environment for pollination in an urban area and aims to review the urban environmental variables which are highly linked to the pollination mediations by the honeybee. The study composed a Maxent model by adopting nine urban environmental variables and the locations of the Apis mellifera's appearances around 52 spots in Seoul. The variables reflect the ecology of the Apis mellifera. Of the urban environmental variables used for the model composition, six variables were found as not having meaningful correlations with the Apis mellifera's appearances and finally, building coverage, actual vegetation and land cover were selected as the appearance variables of the Apis mellifera. The AUC, the reliability indicator of the final model was 0.791 (sd=0.077). And the importance data of the variables used for the model were 55.6%, 27.9%, and 16.5% for building coverage, actual vegetation and land cover, respectively. The result of the study showed that the building coverage has the highest correlation with the appearance of the honeybee. And, as per the actual vegetation, the artificially tree planted area as well as the cultivated field and meadow in an urban area were functioning as the most important environmental conditions for the honeybee to be inhabitable. The study is expected to be utilized as the base material for the urban planning and park green area planning to enhance the potential environment for pollination in an urban area.

Local and regional steppe vegetation palatability at grazing hotspot areas in Mongolia

  • Amartuvshin, Narantsetsegiin;Kim, Jaebeom;Cho, Nanghyun;Seo, Bumsuk;Kang, Sinkyu
    • Journal of Ecology and Environment
    • /
    • 제46권1호
    • /
    • pp.76-84
    • /
    • 2022
  • Background: Climate and livestock grazing are key agents in determining current Mongolian steppe vegetation communities. Together with plant coverage or biomass, palatability of steppe community is regarded as a useful indicator of grassland degradation, in particular, at grazing hotspots in arid and semi-arid grasslands. This study analyzed relationships between livestock grazing pressure and steppe vegetation palatability at three summer pastures with different aridity (dry, xeric, and mesic) and livestock numbers (1,100, 1,800, and 4,100 sheep units, respectively). At each site, it was surveyed coverage, biomass, and species composition of different palatability groups (i.e., palatable [P], impalatable [IP], and trampling-tolerant [TT]) along a 1-km transect from grazing hotspots (i.e., well) in every July from 2015 to 2018. Results: In results, total vegetation coverage increased with wetness, 7 times greater at mesic site than dry one in averages (33.1% vs. 4.5%); biomass was 3 times higher (47.1 g m-2 vs. 15.7 g m-2). Though P was the dominant palatability group, the importance of IP in total coverage increased with aridity from mesic (0.6%) to dry (40.2%) sites. Whereas, TT increased with livestock numbers across sites. Locally, IP was observed more frequently near the wells and its spatial range of occurrence becomes farther along the transects with aridity across sites from mesic (< 100 m) to dry (< 700 m from the well). Conclusions: Our results showed that the importance of IP and its spatial distribution are different at both local and regional scales, indicating that the palatability parameters are sensitive to discern balance between selective-grazing demand and climate-driven foraging supply in Mongolian rangelands.

Multi-temporal analysis of vegetation indices for characterizing vegetation dynamics

  • Javzandulam, Tsend-Ayush;Tateishi, Ryutaro;Kim, Dong-Hee
    • 대한원격탐사학회:학술대회논문집
    • /
    • 대한원격탐사학회 2003년도 Proceedings of ACRS 2003 ISRS
    • /
    • pp.405-407
    • /
    • 2003
  • An attempt has been in this study to delineate the characteristics of spectral signatures of the vegetation in terms of various VIs, particularly made the Normalized Difference Vegetation Index(NDVI), Modified Soil Adjusted Vegetation Index2(MSAVI2) and Enhanced Vegetation Index(EVI). Multitemporal SPOT-4 VEGETATION data from 1998 to 2002 have been used for the analysis. They have been compared with each other for their similarities and differences. The correlations between the vegetation indices observed at various degree of vegetation coverage during their different stages of growth were examined. All of the VIs have shown qualitative relationships to variations in vegetation. Apparently, the NDVI and MSAVI2 are highly correlated for all of the temporal changes, representing the different stages of phenology.

  • PDF

Calculating coniferous tree coverage using unmanned aerial vehicle photogrammetry

  • Ivosevic, Bojana;Han, Yong-Gu;Kwon, Ohseok
    • Journal of Ecology and Environment
    • /
    • 제41권3호
    • /
    • pp.85-92
    • /
    • 2017
  • Unmanned aerial vehicles (UAVs) are a new and yet constantly developing part of forest inventory studies and vegetation-monitoring fields. Covering large areas, their extensive usage has saved time and money for researchers and conservationists to survey vegetation for various data analyses. Post-processing imaging software has improved the effectiveness of UAVs further by providing 3D models for accurate visualization of the data. We focus on determining the coniferous tree coverage to show the current advantages and disadvantages of the orthorectified 2D and 3D models obtained from the image photogrammetry software, Pix4Dmapper Pro-Non-Commercial. We also examine the methodology used for mapping the study site, additionally investigating the spread of coniferous trees. The collected images were transformed into 2D black and white binary pixel images to calculate the coverage area of coniferous trees in the study site using MATLAB. The research was able to conclude that the 3D model was effective in perceiving the tree composition in the designated site, while the orthorectified 2D map is appropriate for the clear differentiation of coniferous and deciduous trees. In its conclusion, the paper will also be able to show how UAVs could be improved for future usability.

녹지의 배치와 식재형태가 열환경저감효과에 미치는 영향 (Temperature Lowering Effects Varied by the Arrangement and Types of Vegetation)

  • 윤용한
    • 아시안잔디학회지
    • /
    • 제17권4호
    • /
    • pp.165-172
    • /
    • 2003
  • 본 연구는 녹지의 배치와 식재형태가 기온저감효과에 미치는 영향을 파악한 결과 다음과 같은 점이 밝혀졌다. 1) 녹지의 기온분포도로부터 고온역은 주변시 가지에서, 저온역은 각 녹지내의 식재지주변과 소하천주변에서 확인되었다. 2) 녹지의 배치와 기온과의 관계를 보면, 저온역은 각 녹지와 거의 일치하고 녹지간 시가지 및 풍하쪽에도 저온역이 형성되었다. 3) 녹지간 시가지와 기온과의 관계를 보면 저온역은 풍하쪽 시가지뿐 아니라 녹지간 시가지에서도 나타났다. 또한, 풍상쪽에 녹지가 존재하지 않은 경우에도 녹지간 시가지는 주변 시가지 보다 낮은 기온이었다. 4) 토지피복비율과 기온에서 식재지, 초지 및 수면이 증가하면 모두 기온저감에 효과적이고, 나지의 증가는 기온상승에 효과적이다. 5) 교목, 소교목의 순으로 그 그루의 증가는 기온저감에 유효하게 관련되어 있는 것이 파악되었다.

경사지에서 고추 정식시기에 따른 토양유실과 유출수에 대한 식생피복 효과 (Effect of Red Pepper Canopy Coverages on Soil Loss and Runoff from Sloped Land with Different Transplanting Dates)

  • 조희래;하상건;현승훈;허승오;한경화;홍석영;전상호;김은진;이동성
    • 한국토양비료학회지
    • /
    • 제43권3호
    • /
    • pp.260-267
    • /
    • 2010
  • As sloped farmland is subject to runoff and soil erosion and consequently require appropriate vegetative coverage to conserve soil and water, a field study was carried out to evaluate the impact of crop canopy coverage on soil loss and runoff from the experimental plot with three different textural types (clay loam, loam, and sandy loam). The runoff and soil loss were examined at lysimeters with 15% slope, 5 m in length, and 2 m in width for five months from May to September 2009 in Suwon ($37^{\circ}$ 16' 42.67" N, $126^{\circ}$ 59' 0.11" E). Red pepper (Capsicum annum L. cv. Daechon) seedlings were transplanted on three different dates, May 4 (RP1), 15 (RP2), and 25 (RP3) to check vegetation coverage. During the experimental period, the vegetation coverage and plant height were measured at 7 day-intervals and then the 'canopy cover subfactor' (an inverse of vegetation cover) was subsequently calculated. After each rainfall ceased, the amounts of soil loss and runoff were measured from each plot. Under rainfall events >100 mm, both soil loss and runoff ratio increased with increasing canopy cover subfactor ($R^2$=0.35, p<0.01, $R^2$=0.09, p<0.1), indicating that as vegetation cover increases, the amount of soil loss and runoff reduces. However, the soil loss and runoff were depending on the soil texture and rainfall intensity (i. e., $EI_{30}$). The red pepper canopy cover subfactor was more highly correlated with soil loss in clay loam ($R^2$=0.83, p<0.001) than in sandy loam ($R^2$=0.48, p<0.05) and loam ($R^2$=0.43, p<0.1) plots. However, the runoff ratio was effectively mitigated by the canopy coverage under the rainfall only with $EI_{30}$<1000 MJ mm $ha^{-1}hr^{-1}$ ($R^2$=0.34, p<0.05). Therefore, this result suggested that soil loss from the red pepper field could be reduced by adjusting seedling transplanting dates, but it was also affected by the various soil textures and $EI_{30}$.

산지사면의 유출 및 토양침식에 대한 에너지 보존 (Energy Conservation for Runoff and Soil Erosion on the Hillslope)

  • 신승숙;박상덕;조재웅;홍종선
    • 한국수자원학회:학술대회논문집
    • /
    • 한국수자원학회 2008년도 학술발표회 논문집
    • /
    • pp.234-238
    • /
    • 2008
  • The energy conservation theory is introduced for investigating processes of runoff and soil erosion on the hillslope system changed vegetation condition by wildfire The rainfall energy, input energy consisted of kinetic and potential energy, is influenced by vegetation coverage and height. Output energy at the outlet of hillslope is decided as the kinetic energy of runoff and erosion soil, and mechanical work according to moving water and soil is influenced dominantly by the work rather than the kinetic energy. Relationship between output and input energy is possible to calculate the energy loss in the runoff and erosion process. The absolute value of the energy loss is controlled by the input energy size of rainfall because energy losses of runoff increase as many rainfall pass through the hillslope system. The energy coefficient which is dimensionless is defined as the ratio of input energy of rainfall to output energy of runoff water and erosion soil such as runoff coefficient. The energy coefficient and runoff coefficient showed the highest correlation coefficient with the vegetation coverage. Maximum energy coefficient is about 0.5 in the hillslope system. The energy theory for output energy of runoff and soil erosion is presented by the energy coefficient theory associated with vegetation factor. Also runoff and erosion soil resulting output energy have the relation of power function and the rates of these increase with rainfall.

  • PDF

옥상녹화조성에 따른 온도저감효과에 관한 연구 -서울대학교 실험구를 중심으로- (The Effect of Temperature Reduction as Influenced by Rooftop Greening)

  • 이동근;윤소원;오승환;장성완
    • 한국환경복원기술학회지
    • /
    • 제8권6호
    • /
    • pp.34-44
    • /
    • 2005
  • The objective of this study is to analyze the thermal properties of various green roof type. The experimental districts, have different soil thickness, soil type, the existence of module and the different kinds of vegetation, had installed. A measurement was conducted in Seoul University to investigate the thermal impacts of rooftop greening. The measurement point of temperature were 30, located in soil surface, middle of the soil layer, under the module, hard surface and soffit surface of each experimental district. The experimental investigation lasted from 6th August to 29th August, a total of 24 days. The results showed that green roof can contribute thermal benefits by soil and vegetation and reduce building energy consumption by a role of insulation. It's also better to make soil thickness over 20cm and various vegetation that should be more effective. The district installed only soil also could be effective for reducing the temperature of roof surface. Therefore, the increase of soil thickness and various vegetation could reduce more temperature of roof surface and building energy consumption. Also, it's helpful to reduce temperature that plant coverage rate be raised.