• Title/Summary/Keyword: Winter vegetation

Search Result 100, Processing Time 0.029 seconds

Marine Algal Communities around Oryukdo, Busan, Korea (부산시 오륙도 주변 해역의 해조 군집)

  • Choi, Jung Hwa;Choi, Chang Geun
    • Korean Journal of Fisheries and Aquatic Sciences
    • /
    • v.47 no.6
    • /
    • pp.960-972
    • /
    • 2014
  • Marine algal flora and community structure were seasonally investigated at Oryukdo, on the southeast coast of Korea, from March 2011 to February 2014. A Total of 66 seaweed species including 6 green, 7 brown and 53 red algae were identified and 23 species were found throughout the survey period. Seaweed biomass was maximal during summer in 2012 (2276.2 g wet weight $m^{-2}$) and minimal in winter in 2012 (9.1 g wet weight $m^{-2}$). The dominant species in term of biomass were Undaria pinnatifida, Dictyopteris prolifera, Dictyota dichotoma, Sargassum horneri, Rhodymenia intricata, Acrosorium polyneurum, and Polyneura japonica during the suvery period. The flora could be classified into six functional groups: coarsely branched form (30.3%), filamentous form (24.2%), thick leather form (19.7%), sheet form (15.2%), jointed calcareous form (7.6%), and crustose form (3.0%). The numbers of marine algal species in the Oryukdo area were markedly reduced when compared with previous studies at Dongbaekseom in 1971. These results suggest possible future changes in the algal vegetation, considering the physical and chemical pollution loadings in the coastal marine environment of this area.

Development of Biomass Evaluation Model of Winter Crop Using RGB Imagery Based on Unmanned Aerial Vehicle (무인기 기반 RGB 영상을 이용한 동계작물 바이오매스 평가 모델 개발)

  • Na, Sang-il;Park, Chan-won;So, Kyu-ho;Ahn, Ho-yong;Lee, Kyung-do
    • Korean Journal of Remote Sensing
    • /
    • v.34 no.5
    • /
    • pp.709-720
    • /
    • 2018
  • In order to optimize the evaluation of biomass in crop monitoring, accurate and timely data of the crop-field are required. Evaluating above-ground biomass helps to monitor crop vitality and to predict yield. Unmanned Aerial Vehicle (UAV) imagery are being assessed for analyzing within field spatial variability for agricultural precision management, because UAV imagery may be acquired quickly during critical periods of rapid crop growth. This study reports on the development of remote sensing techniques for evaluating the biomass of winter crop. Specific objective was to develop statistical models for estimating the dry weight of barley and wheat using a Excess Green index ($E{\times}G$) based Vegetation Fraction (VF) and a Crop Surface Model (CSM) based Plant Height (PH) value. As a result, the multiple linear regression equations consisting of three independent variables (VF, PH, and $VF{\times}PH$) and above-ground dry weight provided good fits with coefficients of determination ($R^2$) ranging from 0.86 to 0.99 with 5 cultivars. In the case of the barley, the coefficient of determination was 0.91 and the root mean squared error of measurement was $102.09g/m^2$. And for the wheat, the coefficient of determination was 0.90 and the root mean squared error of measurement was $110.87g/m^2$. Therefore, it will be possible to evaluate the biomass of winter crop through the UAV image for the crop growth monitoring.

Habitat Characteristics and Distribution of Cymbidium kanran Native to Jejudo, Korea (제주한란의 자생환경 특성 및 분포에 관한 연구)

  • Lee, Jong Suk
    • Journal of the Korean Society of Environmental Restoration Technology
    • /
    • v.7 no.1
    • /
    • pp.40-49
    • /
    • 2004
  • This work carried out to define the characteristic of Cymbidium kanran habitat at Mt. Halla in Jejudo, Korea from the ecological point of view including geological and topographical features, air and soil temperature, relative humidity, fluctuations of light intensity, habitat vegetation, distribution altitude, area limit, and etc. And another goal of this study consider the conservation counterplan of the cymbidium habitat. Natural distribution areas of the cymbidium were observed more abundantly on the well drained south and east-facing slopes. Soil acidity was ranged from pH 4.1 to 5.3, and electric conductivity was ranged from 176.4 to 299.9 us/cm (average 215.3 us/cm). Base-saturation percentage of the habitat soil was below 50%, bulk density 0.42g/$cm^2$, particle density 2.05g/$cm^2$, humus content 26%, total nitrogen 0.82%, available phosphate 4.2 mg/kg, exchangeable potassium 0.63 Cmol/kg, calcium 0.44 Cmol/kg and magnesium 0.67 Cmol/kg. Annual mean air temperature was $15.4^{\circ}C$, however, air temperature was ranged $11.7{\sim}18.2^{\circ}C$ in spring, $21.2{\sim}23.8^{\circ}C$ in summer, $12.8{\sim}22.0^{\circ}C$ in fall and $5.5{\sim}7.8^{\circ}C$ in winter season. Annual mean soil temperature at depth of 10cm was $13.2^{\circ}C$ And minimum value was recorded $4.7^{\circ}C$ on January, and maximum value $22.5^{\circ}C$ on August. Relative humidity was ranged 90.8~94.7% in summer, 80.8~91.5% in fall and 77.6~84.2% in winter season. Minimum value was 56.5% on December, and maximum value was 100% on July and August. Light intensities were ranged from 400 to 1,800 lux at the greater part of Cymbidium kanran sites in Jejudo. Summer regarded as an lower light intensities was recorded to be range of 500~600 lux; however, autumn and winter were shown higher light regimes ranged from 3,500 to 3,800 lux. Therefore, one must be suprised that the cymbidium grow at the light condition of 6 lux (minimum) or 10,000 lux (maximum). Tree species keeping higher frequency rate and density were Eurya japonica, Camellia japonica, Castanopsis cuspidata, Carpinus laxiflora and Pinus densiflora. Number of trees growing in a 5${\times}$5m quardrat was 35 as an average, and proportion of evergreen versus deciduous was 5:1. Distribution altitude of the orchid habitat was ranged from 120m (low) to 840m (high) from sea level on the south facing slope of Mt. Halla, and was ranged eastern borderline of Gujwaup, Bukjejugun to western boundaries of Jungmundong, Seogwipo city. For the stable conservation of Cymbidium kanran habitat, sunlight regimes must be increased more by means of cutting trees or twigs in the site.

The Optimal GSD and Image Size for Deep Learning Semantic Segmentation Training of Drone Images of Winter Vegetables (드론 영상으로부터 월동 작물 분류를 위한 의미론적 분할 딥러닝 모델 학습 최적 공간 해상도와 영상 크기 선정)

  • Chung, Dongki;Lee, Impyeong
    • Korean Journal of Remote Sensing
    • /
    • v.37 no.6_1
    • /
    • pp.1573-1587
    • /
    • 2021
  • A Drone image is an ultra-high-resolution image that is several or tens of times higher in spatial resolution than a satellite or aerial image. Therefore, drone image-based remote sensing is different from traditional remote sensing in terms of the level of object to be extracted from the image and the amount of data to be processed. In addition, the optimal scale and size of data used for model training is different depending on the characteristics of the applied deep learning model. However, moststudies do not consider the size of the object to be found in the image, the spatial resolution of the image that reflects the scale, and in many cases, the data specification used in the model is applied as it is before. In this study, the effect ofspatial resolution and image size of drone image on the accuracy and training time of the semantic segmentation deep learning model of six wintering vegetables was quantitatively analyzed through experiments. As a result of the experiment, it was found that the average accuracy of dividing six wintering vegetablesincreases asthe spatial resolution increases, but the increase rate and convergence section are different for each crop, and there is a big difference in accuracy and time depending on the size of the image at the same resolution. In particular, it wasfound that the optimal resolution and image size were different from each crop. The research results can be utilized as data for getting the efficiency of drone images acquisition and production of training data when developing a winter vegetable segmentation model using drone images.

Study on Changes of NDVI by Growth Stages of Winter Forage Crop Using a Ground-based Camera System (지상 분광 자동측정 시스템을 이용한 동계 사료작물의 생육 시기별 식생지수 변화 연구)

  • Young, Shin Jae;Min, Lee Jun;Hak, Yang Seung;Jae, Lim Kyoung;Jin, Lee Hyo
    • Journal of The Korean Society of Grassland and Forage Science
    • /
    • v.41 no.4
    • /
    • pp.295-301
    • /
    • 2021
  • In this study we developed the ground-based multispectral camera system to determine proper period to build and apply the calibration equation for dry matter of winter forage corps monitoring by unmanned aerial vehicle (UAV). Normalized difference vegetation index (NDVI) of rye, whole barley and Italian ryegrass (IRG) were measured and the growth period was divide by NDVI increasing period and decreasing period. Day of the maximum NDVI value of rye, whole barley and IRG were 8th, 9th and 5th April 2020. Regression analysis showed that the correlation coefficients (R2) between dry matter and NDVI were 0.84, 0.84, 0.78 during NDVI increasing period and 0.00, 0.02, 0.27 during NDVI decreasing period. Therefore, detailed NDVI monitoring is required to determine the proper period to build and apply the calibration equation and the ground-based multispectral camera system was effective tool for detailed NDVI monitoring.

Characteristics of Breeding Bird Community in Relation to Altitude and Vegetation in Jirisan National Park (지리산국립공원 해발고도와 식생에 따른 번식기 조류군집의 특성)

  • Lee, Do-Han;Kwon, Hye-Jin;Song, Ho-Kyung
    • Korean Journal of Environment and Ecology
    • /
    • v.22 no.5
    • /
    • pp.471-480
    • /
    • 2008
  • This study was conducted to investigate the characteristics of breeding bird community in relation to altitude and vegetation in Jirisan National Park. The survey was carried over 4 study sites by point counts method to figure out habitat environment and breeding bird community from March to August in 2006. The study results are summarized as follows: Total 32 species were recorded, and 27 species and density of 37.31 ea/ha in low altitude mixed forest, 23 species and 34.99 ea/ha in low altitude deciduous forest, 18 species and 23.95 ea/ha in high altitude mixed forest, 19 species and 20.21 ea/ha in high altitude deciduous forest, respectively. Eleven species were observed only in the low altitude sites, 4 species were observed only in the high altitude sites. Number of species and density were high in the low altitude sites, and they were high in the mixed forests. In nesting guild analysis, the low altitude sites are similarly found species number of three types but canopy nesting species in the high altitude sites are advent less. In foraging guild analysis, the species number of canopy foraging appeared most highly in all study sites. In the difference analysis of each species density. Four species which are showed the difference in the low altitude sites, owing to vegetation. Long-tailed Tit(Aegithalos caudatus) and Great tit(Parus major) are difference because of difference in volume of canopy layer, and Coal Tit(Parus ater) was difference because of coniferous forest preference quality. Four species(Hazel Grouse, Winter Wren, Pale Thrush, Yellow-throated Bunting) which are showed the difference of the density in the high altitude sites because of thick growth of the bush layer. Ten species which are showed the difference in study sites, owing to altitude. Oriental Cuckoo(Cuculus saturatus), Winter Wren(Troglodytes troglodytes), Siberian Blue Robin(Luscinia cyane), Arctic Warbler(Phylloscopus borealis), Coal Tit(Parus ater), and Yellow-throated Bunting(Emberiza elegans) appeared highly in the high altitude sites, Pale Thrush(Turdus pallidus), Long-taild Tit(Aegithalos caudatus), Varied Tit(Parus varius), and Eurasian Nuthatch(Sitta europaea) appeared highly in the low altitude sites. It seems that bush layer coverage volume and canopy layer total coverage volume do influences on the breeding bird community, because the bush layer was thick growth, and canopy layer coverage volume was difference. It would be needed the management and maintenance of bush layer coverage volume and canopy layer with multi-layer structure to increase foliage height diversity and total coverage volume for the protection and management of bird community in Jirisan National Park.

A Study on Changes in Habitat Enviroment of Wild Birds in Urban Rivers according to Climate Change - A Case Study of Tancheon Ecological and Landscape Conservation Area - (기후변화에 따른 도시하천의 야생조류 서식환경 변화 연구 - 탄천 생태·경관보전지역를 사례로 -)

  • Han, Jeong-Hyeon;Han, Bong-Ho;Kwak, Jeong-In
    • Journal of the Korean Institute of Landscape Architecture
    • /
    • v.52 no.2
    • /
    • pp.79-95
    • /
    • 2024
  • The purpose of this study was to find the changes in the habitat of wild birds caused by climate change in urban rivers and protected areas that greatly require ecological functions. In the future, this study can be used as a management index to protect the urban river ecosystem and maintain the health of sustainable urban rivers, thereby ensuring biodiversity. The Tancheon Ecological and Landscape Conservation Area, selected as a target site, has been affected by climate change. The four seasons of Korea have a distinct temperate climate, but the average annual temperature in Seoul has risen by 2.4-2.8℃ over the last 40 years. Winter temperatures tended to gradually increase. Precipitation, which was concentrated from June to August, is now changing into localized torrential rain and a uniform precipitation pattern of several months. Climate change causes irregular and unforeseen features. Climate change has been shown to have various effects on urban river ecosystems. The decrease in the area of water surface and sedimentary land impacted river shape change and has led to large-scale terrestrialization. Plants showed disturbance, and the vegetation was simplified. The emergence of national climate change indicator species, the development of foreign herbaceous plants, the change of dry land native herbaceous species, and wet intelligence vegetation were developed. Wild birds appeared in the territory of winter-summer migratory. In addition, species change and the populations of migratory birds also occurred. It was judged that fluctuations in temperature and precipitation and non-predictive characteristics affect the hydrological environment, plant ecology, and wild birds connecting with the river ecosystem. The results of this study were to analyze how climate change affects the habitat of wild birds and to develop a management index for river ecological and landscape conservation areas where environmental and ecological functions in cities operate. This study can serve as a basic study at the level of ecosystem services to improve the health of urban rivers and create a foundation for biodiversity.

Species Diversity of Riparian Vegetation by Soil Chemical Properties and Water Quality in the Upper Stream of Mankyeong River (만경강 상류 수질 및 식생분포와 토양환경에 따른 하천식생의 종 다양성)

  • Lee, Kyeong-Bo;Kim, Chang-Hwan;Lee, Deog-Bae;Kim, Jong-Gu;Park, Chan-Won;Na, Seoung-Yong
    • Korean Journal of Environmental Agriculture
    • /
    • v.22 no.2
    • /
    • pp.100-110
    • /
    • 2003
  • This study was conducted to evaluate influence of chemical properties in the riparian on the species diversity and to get plant information for enhancement of natural purification in Mankyeong River. The concentration of total nitrogen was high in Jeonju and Sam stream, while that of total nitrogen showed the highest peak in Winter. Concentrations of $NH_4-N$ was $0.01{\sim}0.06\;mg/L$ in Gosan and Soyang stream. The water quality of upstream along with Mankyeong River was suitable for the irrigation source. The riparian vegetation was investigated by Zurich-Montpellier school's method from June, 2001 to September, 2002. The number of riparian plants were 59 families, 129 genera, 165 species, 20 varieties in Gosancheon, on the while 53 families, 111 genera, 141 species, 19 varieties in Soyangcheon. The number of riparian plants in Bari basin was higher than that of other sites namely, 73 families, 134 genera, 218 species, 33 varieties. Riparian vegetation was consisted of 12 plant communities. The contents of organic matter, total nitrogen and electrical conductivity had negative relationship with species diversity (Species richness index, Heterogeneity index, Species evenness index Species number). On the while, species diversity had positive relationship with soil pH. Species diversify of the plant communities were affected by topography and disturbance.

Ecological Guidelines for Creation of Eco-washland (생태 천변저류지의 생태학적 조성계획기준)

  • Chun, Seung-Hoon;Choi, Jun-Gil;Yoo, Jeong-Chil
    • Journal of Wetlands Research
    • /
    • v.10 no.1
    • /
    • pp.39-47
    • /
    • 2008
  • An eco-washland is increasingly getting attentions as a new alternative plan for management of water resources because of role as flooding control and ecological park without social and ecological side effects. However, there is a lack of study regarding technological development and ecological guidelines to create eco-washland. This study was carried out to suggest ecological guidelines necessary for engineering process to create eco-washland. A study site was the lower reach of Seokjang stream connecting to Yimjin river, a candidate of new eco-washland, and Kumsa area in Namhan river was selected as a reference site. The analysis of ecological characteristics focused on vegetation, fishes, and birds. Major vegetation communities, composed of dominant species such as Salix koreensis, Salix gracylistyla, Miscanthus sacchariflorus, Phragmites communis, etc., formed physical conditions along with other land uses including open water, sandbar, cultivated land, etc. Dominant species of fishes were some species belonging to Cyprinidae and Acheilognathinae, and in case of birds Anser albifrons, Anas platyrhychos, Anas poecilorhyncha belonging to waterbirds and Paradoxornis webbinanus dependent to forest edge were dominantly distributed. The results showed that complex wetland types associated with partially deep water and upland was the optimal eco-hydrological condition of washland. Cyprinidae and Acheilognathinae in case of fish and Egretta spp. (spring season) and Anas spp. (winter season) in case of bird were selected as target species for the these wetland types. Finally, a detail planning criteria to create habitats of these target species were discussed in terms of spawning, breeding, feeding, resting, refuge, nesting, etc.

  • PDF

Level 3 Type Land Use Land Cover (LULC) Characteristics Based on Phenological Phases of North Korea (생물계절 상 분석을 통한 Level 3 type 북한 토지피복 특성)

  • Yu, Jae-Shim;Park, Chong-Hwa;Lee, Seung-Ho
    • Korean Journal of Remote Sensing
    • /
    • v.27 no.4
    • /
    • pp.457-466
    • /
    • 2011
  • The objectives of this study are to produce level 3 type LULC map and analysis of phenological features of North Korea, ISODATA clustering of the 88scenes of MVC of MODIS NDVI in 2008 and 8scenes in 2009 was carried out. Analysis of phenological phases based mapping method was conducted, In level 2 type map, the confusion matrix was summarized and Kappa coefficient was calculated. Total of 27 typical habitat types that represent the dominant species or vegetation density that cover land surface of North Korea in 2008 were made. The total of 27 classes includes the 17 forest biotopes, 7 different croplands, 2 built up types and one water body. Dormancy phase of winter (${\sigma}^2$ = 0.348) and green up phase in spring (${\sigma}^2$ = 0.347) displays phenological dynamics when much vegetation growth changes take place. Overall accuracy is (851/955) 85.85% and Kappa coefficient is 0.84. Phenological phase based mapping method was possible to minimize classification error when analyzing the inaccessible land of North Korea.