• Title/Summary/Keyword: ecological disturbance

Search Result 285, Processing Time 0.028 seconds

Floristic Study of Gayasan National Park in Korea (가야산국립공원의 관속식물상)

  • Han, Seahee;Leem, Hyosun;Jang, Hyun-Do;Kim, Yoon-Young;So, Soonku
    • Korean Journal of Plant Resources
    • /
    • v.35 no.2
    • /
    • pp.248-288
    • /
    • 2022
  • The study on vascular plants of Gayasan National Park was conducted in 2016 over a period of 34 days from March to October 2016. As the study, a total of 768 taxa were recorded, including 118 families, 396 genera, 691 species, 15 subspecies, 51 varieties, and 11 forms. In the vascular plants, four endangered wild plants were recorded, Ponerorchis cucullata (L.) X.H.Jin, Trientalis europaea var. arctica (Fisch.) Ledeb., Cypripedium macranthos Sw., and Pedicularis hallaisanensis Hurus. Taxa of Least Concern (LC) or higher level on National Red List published by the Ministry of Environment of Korea were 21 taxa for example Tricyrtis macropoda Miq., and Lilium cernuum Kom. A total of 37 Korean endemic plants were investigated for example Abies koreana E.H.Wilson and Impatiens atrosanguinea (Nakai) B.U.Oh & Y.P.Hong. A total of 162 taxa of floristic regional indicators (3rd to 5th degree) were investigated including 9 taxa of V, 15 taxa of IV, 38 taxa of III, 45 taxa of II, and 53 taxa of I. Naturalized plants were recorded a total of 46 taxa with a Naturalization Index of 6.0%, the Urbanization Index was calculated to be 14.3% and 5 taxa of ecosystem disturbance plants were investigated such as Sicyos angulatus L., Rumex acetosella L., and Humulus scandens (Lour.) Merr. As the result of comparison with previous studies, in this study a total of 206 taxa were newly identified including 62 families, 144 genera, 184 species, 2 subspecies, 15 varieties, and 5 forms.

Analysis of Land Cover Composition and Change Patterns in Islands, South Korea (우리나라 도서지역의 토지피복과 변화패턴 분석)

  • Kim, Jaebeom;Lee, Bora;Lee, Ho-Sang;Cho, Nanghyun;Park, Chanwoo;Lee, Kwang-Soo
    • Korean Journal of Agricultural and Forest Meteorology
    • /
    • v.24 no.3
    • /
    • pp.190-200
    • /
    • 2022
  • In this study, the island's land-use and land-cover change (LULCC) is analyzed in South Korea using remotely sensed land cover data(Globeland 30) acquired from 2000 to 2020 to meet the requirement of providing practical information for forest management. Analysis of LULCC between the 2000 and 2020 images revealed that changes to agricultural land were the most common type of change (7.6% of pixels), followed by changes to the forest (5.7%). The islands forests maintain 157,246 ha (42.2% of the total island area). Land cover types that changed to the forest from grasslands were 262 islands, while reverse cases have occurred on 421 islands. These 683 islands have a possibility of transition and disturbance. The artificial land class was newly calculated in 22 islands. The forests, which account for 42.2% of the 22 island area, turned into grassland, and 27.8% of agricultural land and grassland turned into forests. The development of artificial land often affects developed areas and surrounding areas, resulting in deforestation, management of agriculture, and landscaping. This study can provide insights concerning the fundamental data for assessing ecological functions and constructing forest management plans in islands ecosystems.

Ecological Characteristic of Warm Temperate Vegetation Distributed around Hakdong and Haegeumgang at Geojae Island (거제도 학동 및 해금강 일대에 분포하는 난대림 식생의 생태적 특성 연구)

  • Lee, Soo-Dong
    • Korean Journal of Environment and Ecology
    • /
    • v.36 no.1
    • /
    • pp.72-86
    • /
    • 2022
  • This study was conducted to identify structural characteristics of the evergreen broad-leaved forests distributed in Hak-dong, Geojae island. For a survey, 52 sites were set up in areas with changes in the vegetation community or location environment where Cinnamomum yabunikkei, Neolitsea sericea, and Machilus thunbergii dominated or appeared in the canopy, sub-canopy, or shrub layer. The community classification with TWINSPAN identified the following communities: N. sericea-C. yabunikkei, C. yabunikkei-Camellia japonica, Ca. japonica, Quercus variabilis-Ca. japonica, Pinus thunbergii-Ca. japonica, Castanopsis sieboldii, P. thunbergii, and Platycarya strobilacea-Mallotus japonicus. Considering the result of the study that succession series of warm-temperate forest reflecting the latent natural vegetation is the transition of conifers and deciduous broad-leaved forest to evergreen broad-leaved forest, the communities predominated by the communities predominated by the communities predominated by P. thunbergii, Q. variabilis, and Pl. strobilacea are likely to transform into the evergreen forest predominated by N. sericea and C. yabunikkei. The sites where C. yabunikkei, N. sericea, and Castanopsis sieboldii are dominant in the canopy and sub-canopy layers are likely to maintain the status quo if there is no artificial disturbance. The relationship between the impact of the environmental factors and the vegetation distribution showed silt among the physical properties of the soil directly or indirectly affected it, which was judged to be due to the fact that it was located on a steep slope. The soil acidity (pH) was 5-5.84, electrical conductivity 0.047-0.139 dS/m, and organic matter content was 3.32-12.06%. Although there were differences by the colony, they were generally low.

Occurrence characteristics and management plans of Paspalum distichum and P. distichum var. indutum (습지에서 발생하는 생태계교란야생식물인 물참새피와 털물참새피의 발생특성과 관리방안)

  • In Yong Lee;Seung Hwan Kim;Yong Ho Lee;Adhikari Pradeep;Dong Gun Kim;Sun Hee Hong
    • Korean Journal of Environmental Biology
    • /
    • v.40 no.3
    • /
    • pp.325-334
    • /
    • 2022
  • Paspalum distichum and P. distichum var. indutum are perennial weeds of the family Poaceae that prefer moist environments such as waterfronts and waterways. The origin of both species is North America. P. distichum is distributed all over the world. However, P. distichum var. indutum occurs only in the United States, Japan, and Korea. For this reason, in many countries, P. distichum and P. distichum var. indutum are classified as the same species. In other words, P. distichum var. indutum is a different ecological type of P. distichum. Both species can reproduce and spread mainly by rhizome fragments rather than seeds. This rhizome has a characteristic that it does not germinate if it is buried in the ground with depth of more than 3 cm. As a management method for P. distichum and P. distichum var. indutum in agricultural lands (paddy fields), it is effective to combine cultural control and chemical control methods. In other words, combining deep plowing and harrowing can suppress the budding of water sparrow that has invaded paddy fields or fallow paddy fields. After that, these two species that germinate can be controlled by spraying soil treatment herbicides such as butachlor and thiobencarb or foliar treatment herbicides such as cyhalofop-butyl and fenoxaprop-p-ethyl.

Development of Urban Wildlife Detection and Analysis Methodology Based on Camera Trapping Technique and YOLO-X Algorithm (카메라 트래핑 기법과 YOLO-X 알고리즘 기반의 도시 야생동물 탐지 및 분석방법론 개발)

  • Kim, Kyeong-Tae;Lee, Hyun-Jung;Jeon, Seung-Wook;Song, Won-Kyong;Kim, Whee-Moon
    • Journal of the Korean Society of Environmental Restoration Technology
    • /
    • v.26 no.4
    • /
    • pp.17-34
    • /
    • 2023
  • Camera trapping has been used as a non-invasive survey method that minimizes anthropogenic disturbance to ecosystems. Nevertheless, it is labor-intensive and time-consuming, requiring researchers to quantify species and populations. In this study, we aimed to improve the preprocessing of camera trapping data by utilizing an object detection algorithm. Wildlife monitoring using unmanned sensor cameras was conducted in a forested urban forest and a green space on a university campus in Cheonan City, Chungcheongnam-do, Korea. The collected camera trapping data were classified by a researcher to identify the occurrence of species. The data was then used to test the performance of the YOLO-X object detection algorithm for wildlife detection. The camera trapping resulted in 10,500 images of the urban forest and 51,974 images of green spaces on campus. Out of the total 62,474 images, 52,993 images (84.82%) were found to be false positives, while 9,481 images (15.18%) were found to contain wildlife. As a result of wildlife monitoring, 19 species of birds, 5 species of mammals, and 1 species of reptile were observed within the study area. In addition, there were statistically significant differences in the frequency of occurrence of the following species according to the type of urban greenery: Parus varius(t = -3.035, p < 0.01), Parus major(t = 2.112, p < 0.05), Passer montanus(t = 2.112, p < 0.05), Paradoxornis webbianus(t = 2.112, p < 0.05), Turdus hortulorum(t = -4.026, p < 0.001), and Sitta europaea(t = -2.189, p < 0.05). The detection performance of the YOLO-X model for wildlife occurrence was analyzed, and it successfully classified 94.2% of the camera trapping data. In particular, the number of true positive predictions was 7,809 images and the number of false negative predictions was 51,044 images. In this study, the object detection algorithm YOLO-X model was used to detect the presence of wildlife in the camera trapping data. In this study, the YOLO-X model was used with a filter activated to detect 10 specific animal taxa out of the 80 classes trained on the COCO dataset, without any additional training. In future studies, it is necessary to create and apply training data for key occurrence species to make the model suitable for wildlife monitoring.

Studies on the establishment and characteristics of habitat use of muskrat(Ondrtra zibethicus) in South Korea (사향쥐(Ondrtra cuniculus)의 정착 및 서식지 이용에 관한 연구)

  • Kim, Young-Chae;Hong, Sun Hee;Lee, Changwoo;Kim, Areum;Park, Heebok;Park, Su-Gon;Kim, Minhan;Lee, Do-Hun
    • Korean Journal of Environmental Biology
    • /
    • v.38 no.1
    • /
    • pp.1-15
    • /
    • 2020
  • This study was conducted to determine whether invasive muskrats settle in the natural ecosystem of Korea. The study also aimed to provide information on the selection of target areas, basic behavioral characteristics, and habitat use-related data, all of which are essential for effective management strategy establishment and site management. To this end, a trend in international muskrat management was identified to examine the management direction according to the settlement stage. We also secured the location of 72 domestic farmers and classified five regions in Gyeonggi-do, Chungcheongnam-do, Gyeongsangbuk-do, and Sejong Special Self-governing City into regions with high potential for natural leakage to raise the need for a quick survey. We determined that muskrats successfully settled in the natural ecosystem of Korea, based on the fact that we consistently identified a muskrat habitat at the same point for three years, from 2016 to 2018, the age of the captured population was estimated to be 1.2 years, and there had been no additional make-up factors near the habitat since 2012. The muskrats that settled in Korea showed a small home range of 0.0027 ㎢ (MCP 95%) and were estimated to show regular mobility before Spring and Autumn. Also, the areas where the muskrat habitat was observed had a high level of habitat environment disturbance and their ecological and food intake characteristics reflected that disturbance. Muskrat traces were high in hydrophyte vegetation, which can be used as a hideout in open waters and where the growth of both floating leaved plants and floating plants are prevalent. Since international invasive muskrats have already settled in the domestic ecosystem and there is concern about their proliferation in the future, the government must consider a preemptive response and scientific management.

A Study on the Structure Characteristics of Planting Ground in Incheon International Airport, Korea (인천국제공항 식재기반 구조 및 토양특성 연구)

  • Lee, Seung-Won;Han, Bong-Ho;Lee, Kyong-Jae;Kwak, Jeong-In;Yeum, Jung-Hun
    • Journal of the Korean Institute of Landscape Architecture
    • /
    • v.43 no.3
    • /
    • pp.77-91
    • /
    • 2015
  • This study aims to suggest adequate soil management through the analysis of physicochemical properties of soil in the planting grounds of Incheon International Airport, which was constructed on a massive land reclamation site. Study areas were 5 sites at the international business complex, the passenger terminal, the airport support complex, the free trade zone, and the access road. Soil profile analysis showed that 9 plots out of the 27 plots were hardpan and heterospere within 80cm from the soil surface. The earth laid on the ground was categorized as gravel based soil(4 plots), dredged soil from the sea bottom and mixed reclamation materials(2 plots), clay with poor permeability(3 plots) and waste construction material(1 plot). Average soil hardness was $11.5kg/cm^2$ and soil textures were sandy soil, sandy loam and loamy sand. Average soil pH was 6.7 and average organic matter content was 0.7%. Electrical conductivity was 0.0dS/m and exchangeable cation concentrations were $Ca^{2+}$ 3.4cmol/kg, $Mg^{2+}$ 1.5cmol/kg, $K^+$ 0.3cmol/kg and $Na^+$ 1.0cmol/kg. Average cation exchange capacity was 11.0cmol/kg. Although average figures in Solum mostly meet the landscape design criteria, properties of each soil layer showed various values sometimes over the limit. Base saturations were $Ca^{2+}$ 29.9%, $Mg^{2+}$ 13.3% and $K^+$ 3.7% for lower soil, $Ca^{2+}$ 33.3%, $Mg^{2+}$ 17.0% and $K^+$ 2.7% for mid-soil and $Ca^{2+}$ 32.6%, $Mg^{2+}$ 12.2% and $K^+$ 1.9% for upper soil. Exchangeable sodium percentages were 16.4% for lower soil, 7.5% for mid-soil and 4.7% upper soil. Sodium adsorption rates were 0.8 for lower soil, 0.3 for mid-soil and 0.2 for upper soil. Factors affecting to the vegetation growth were heterogeneity and poorness of solum, disturbance of dredged soils, high soil hardness including hardpan in the subsurface soil layer and shallow effective soil depth, high soil acidity, imbalance of base contents, low organic matter content and low available phosphate levels in the soil.

Diversity, Spatial Distribution and Ecological Characteristics of Relict Forest Trees in South Korea (한국 산림유존목의 다양성, 공간 분포 및 생태 특성)

  • CHO, Hyun-Je;Lee, Cheol-Ho;Shin, Joon-Hwan;Bae, Kwan-Ho;Cho, Yong-Chan;Kim, Jun-Soo
    • Journal of Korean Society of Forest Science
    • /
    • v.105 no.4
    • /
    • pp.401-413
    • /
    • 2016
  • Forest resources utilization and variable disturbance history have been affected the rarity and conservation value of forest relict trees, which served as habitat for forest biodiversity, important carbon stock and cultural role include human and natural history in South Korea. This study was conducted to establish the baseline data for forest resources conservation by clarifying species diversity, spatial distribution and ecological characteristics (individual and habitat) of forest relict trees (DBH > 300 cm) based on the data getting from mountain trail, high resolution aerial photos and field professionals and field survey. As results, 54 taxa (18 family 32 genus 48 species 1 subspecies 3 variety and 2 form) as about 22% of tree species in Korea was identified in the field. 837 individuals of forest relict trees were observed and the majority of the trees was in Pinaceae, deciduous Fagaceae and Rosaceae, which families are abundant in population diversity. High elevation area was important to relict trees as mean altitudinal distribution was 1,200 m a.s.l as likely affected by human activity gradients and mid-steep slope and North aspect was important environment for the trees remain. Many individuals exhibited 'damage larger branch' (55.6%) and consequent relatively lower mean canopy coverages (below 80%). Synthetically, present diversity and abundance of relict forest trees in South Korea were the result of complex process among climate variation, local weather and biological factors and the trees of big and old were estimated to important forest biodiversity elements. In the future, clarifying the role and function of relict trees in forest ecosystem, in- and ex- situ programmes for important trees and habitat, and activities for building the background of conservation policy such as "Guideline for identifying and measurement of forest relict trees".

Characteristics of Marine Algal Communities in the Spring at Gijang-gun, Busan (부산시 기장군 연안의 춘계 해조 군집 특성)

  • Jung, Seung-Wook;Choi, Chang-Geun
    • Journal of the Korean Society of Marine Environment & Safety
    • /
    • v.26 no.2
    • /
    • pp.175-185
    • /
    • 2020
  • Quantitative and qualitative surveys were conducted during scuba diving activity between May 2017 and June 2017 in order to analyze spring marine algal community structure at Gijang-gun, Busan. A total of 121 species including 13 (10.7 %) Chlorophyta, 18 (14.9 %) Phaeophyta, and 90 (74.4 %) Rhodophyta were identified. The species count in the subtidal zone (110 species) was twice as high as in the intertidal zone (56 species). In terms of regions, 88,76, and 75 species were found in Mundong, Gongsu, and Daebyeon, respectively. Mean biomass for the whole study area was 1,501.5 g·m-2, higher for the subtidal zone (1,869.4 g·m-2) than for the intertidal zone (1,133.5 g·m-2). Mean biomass by region values were 2,234.0 g·m-2, 1,228.1 g·m-2, and 1,044.4 g·m-2 for Mundong, Gongsu, and Daebyeon, respectively. Ulva australis, Sargassum thunbergii, and Corallina pilulifera had high biomass in the intertidal zone, while Sargassum macrocarpum, Undaria pinnatifida, and Phycodrys fimbriata had high biomass in the subtidal zone. The composition ratio of marine algal functional forms suggests that the entire study area had 'Low' status, and all sites fell within 'Low' to 'Moderate' status. Results indicate that opportunistic species are widely distributed throughout the Gijang-gun coast, hence potential effects of disturbance and environmental pollution should be considered. Seaweed farming in particular - a major activity along the Gijang-gun coast -, together with effects of other anthropogenic activities such as national fishing port development and the coastal improvement project, could have long-term effects on marine algal communities. Therefore, long-term monitoring and management plans for marine algal communities will be required.

Ecological Characteristics and Management Proposal of Abeliophyllum distichum Subpopulations in the Byeonsanbando National Park (변산반도국립공원 내 미선나무 아개체군의 생태적 특성과 관리제언)

  • Lim, Dong-Ok;Hwang, In-Chon;Choi, Hyon-Woo;Kim, Yong-Shik
    • Korean Journal of Environment and Ecology
    • /
    • v.23 no.2
    • /
    • pp.116-126
    • /
    • 2009
  • This study was carried out focused an ecological characteristics and habitat management of Abeliophyllum distichum subpopulations in the Byeonsanbando National Park, Korea. Among three subpopulations of the target species in the studied area, Gamaso region are known as translocation site due to the dam construction while the wild populations which is located at both the lower terrain of the Buandaem bank and Chongnim-ni, which is designated as Natural Monument No 370, is threat due to an intensive site management likes clearance of scrub amongst the Abeliophyllum plants. Vascular plant taxa in the studied sites were summarized as 182 taxa; 65 families, 143 genera, 164 species, 17 varieties and 1 form, and Gamaso area, the lower terrain of the Buandaem and Cheongnim-ni areas are summarized as 75, 102 and 89 taxa, respectively. The plant species likes persimmon tree, paulownia tree and wild mulberry tree are dominant species in the Gamaso subpopulation, while Quercus variabilis is dominant at the lower terrain of the Buandaem. The intensive site management was applied to the Cheongnim-ni subpopulation, one of the original wild habitats of the species. The population dymanics was varied; the one or two sprouting number of stems was over 87% both at Gamaso area and the lower terrain of the Buandam, while the Cheongnim-ni subpopulation recorded as 74.8%. Also three sprouting number recorded as 16% and as 9.2% for sprouting on numbers of four to eleven. The invaded species likes Chenopodium album, Rumex obtusifolius, Phytolacca americana, Pharbitis nil, Solanum lyratum, Erigeron canadensis and Erigeron annuus, were found at the wild habitat of the species, and those invaded species grow faster than Abeliophyllum plants. Among three habitats of the target species in the studied area, the habitat which in located at the lower terrain of the Buandam and Gamaso region are known as translocated due to the dam construction, and wild subpopulation at Chongnim-ni, which is designated as Natural Monument No 370, is under threatened due to an intensive site management likes clearance of scrub amongst the Abeliophyllumplants. It is one of the evidence that Cuscuta japonica at the population indicated an intensive site management likes clearance of scrub is not proper habitat management protocol. Thus, further researches should be followed to determine the effect of canopy removal and other disturbance factors as management techniques.