• Title/Summary/Keyword: Ecological Factors

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Analysis of Environmental Factors and Change of Vascular Plant Species along an Elevational Gradients in Baekdansa, Mt. Taebaeksan National Park (태백산국립공원 백단사코스의 고도별 관속식물상 변화와 환경요인 분석)

  • An, Ji-Hong;Park, Hwan-Joon;Lee, Sae-rom;Seo, In-Soon;Nam, Gi-Heum;Kim, Jung-Hyun
    • Korean Journal of Environment and Ecology
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    • v.33 no.4
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    • pp.378-401
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    • 2019
  • This study generated a list of plants in eight sections from the Baekdansa ticket office (874m) to Cheonjedan (1,560m) divided in the interval of 100m above sea level to examine the species diversity patterns and distribution changes of the vascular plants at different altitudes in Taebaeksan National Park. Four site surveys found a total of 385 taxa: 89 families, 240 genera, 345 species, 5 subspecies, 34 varieties, and 1 form. A result of analyzing the change of species diversity along elevational gradients showed that it decreased with increasing elevation and then increased from a certain section. A result of analyzing habitat affinity types showed that the proportion of forest species increased with increasing elevation. On the other hand, the ruderal species appeared at a high rate in the artificial interference section. A result of comparing the proportion of woody and herb plants showed that the woody plants gradually increased with elevation and rapidly decreased in the artificial interference section. On the other hand, the herb plants showed the opposite trend. A result of analyzing the change of distribution of species according to altitude with the DCA technique showed that the vascular plants were divided into three groups according to the elevation in order on the I axis with the boundaries at 900m and 1,300m above sea level. The arrangement of each stand from right to left along the altitude on the I axis with a significant correlation with warmth index (WI) confirmed that the temperature change along the altitude could affect the distribution of vascular plants, composition, and diversity. Therefore, the continuous monitoring is necessary to confirm ecological and environmental characteristics of vegetation, distribution ranges, changes of habitat. We expect that the results of this study will be used as the basic data for establishing the measurement measures related to the preservation of biodiversity and climate change.

Coarse Woody Debris (CWD) Respiration Rates of Larix kaempferi and Pinus rigida: Effects of Decay Class and Physicochemical Properties of CWD (일본잎갈나무와 리기다소나무 고사목의 호흡속도: 고사목의 부후등급과 이화학적 특성의 영향)

  • Lee, Minkyu;Kwon, Boram;Kim, Sung-geun;Yoon, Tae Kyung;Son, Yowhan;Yi, Myong Jong
    • Journal of Korean Society of Forest Science
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    • v.108 no.1
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    • pp.40-49
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    • 2019
  • Coarse woody debris (CWD), which is a component of the forest ecosystem, plays a major role in forest energy flow and nutrient cycling. In particular, CWD isolates carbon for a long time and is important in terms of slowing the rate of carbon released from the forest to the atmosphere. Therefore, this study measured the physiochemical characteristics and respiration rate ($R_{CWD}$) of CWD for Larix kaempferi and Pinus rigida in temperate forests in central Korea. In summer 2018, CWD samples from decay class (DC) I to IV were collected in the 14 forest stands. $R_{CWD}$ and physiochemical characteristics were measured using a closed chamber with a portable carbon dioxide sensor in the laboratory. In both species, as CWD decomposition progressed, the density ($D_{CWD}$) of the CWD decreased while the water content ($WC_{CWD}$) increased. Furthermore, the carbon concentrations did not significantly differ by DC, whereas the nitrogen concentration significantly increased and the C/N ratio decreased. The respiration rate of L. kaempferi CWD increased significantly up to DC IV, but for P. rigida it increased to DC II and then unchanged for DC II-IV. Accordingly, except for carbon concentration, all the measured characteristics showed a significant correlation with $R_{CWD}$. Multiple linear regression showed that $WC_{CWD}$ was the most influential factor on $R_{CWD}$. $WC_{CWD}$ affects $R_{CWD}$ by increasing microbial activity and is closely related to complex environmental factors such as temperature and light conditions. Therefore, it is necessary to study their correlation and estimate the time-series pattern of CWD moisture.

The relationship between the population characteristics and physical habitat of Manchurian trout(Brachymystax lenok tsinlingensis) in the Geybangcheon stream (계방천에 서식하는 열목어의 개체군 특성 및 물리적 서식환경과의 상관관계)

  • Ko, Min Seop;Choi, Jun Kil;Lee, Hwang Goo
    • Korean Journal of Environmental Biology
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    • v.39 no.1
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    • pp.108-118
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    • 2021
  • The purpose of this study was to provide baseline ecological data for the conservation of the Manchurian trout habitat through the investigation of the growth status of Brachymystax lenok tsinlingensis, and Pearson's correlation analysis (PCA) between the B. lenok tsinlingensis population and the use of the land around Gyebangcheon stream. Sampling was conducted twice in July, September, and October 2018. During the July and September surveys, 882 individuals belonging to 13 species from six families were collected. The dominant species was Rhynchocypris kumgangensis and the subdominant species was Zacco koreanus. The total number of B. lenok tsinlingensis collected was 99. The results of the length-weight relationship in the B. lenok tsinlingensis population were analyzed with a regression coefficient b value of 3.1272 and a condition factor (k) value of 0.0006. Therefore, the growth condition of B. lenok tsinlingensis was regarded as fairly good. The QHEI(Qualitative habitat evaluation index) value in the B. lenok tsinlingensis habitat was 119.5(±0.5)-153.5(±0.5), indicating optimal-suboptimal conditions. As a result of the HIS (Habitat suitability index) analysis, it was confirmed that the optimal habitat for B. lenok tsinlingensis was 0.45-0.55m and >1 m in water depth, 0.55-0.65 m s-1 in water velocity, and boulder in the substrate. The ratio of the land use in this study site was analyzed as 66.26-96.31% for forest and grassland areas, 0.00-23.79% for agricultural areas, 0.00-4.19% for urbanized areas, and 3.69-8.87% for others. Correlation analysis of the number of B. lenok tsinlingensis and various factors revealed statistically significant correlations between QHEI and forest and grassland areas, agricultural areas, and urbanized areas.

Study on Plant Indicator Species of Picea jezoensis (Siebold & Zucc.) Carrière Forest by Topographic Characters - From China (Baekdu-san) to South Korea - (가문비나무림의 지형특성에 따른 식물 지표종에 관한 연구 - 중국 백두산 일대에서 남한까지 -)

  • Byeong-Joo, Park;Tae-Im, Heo;Jun-Gi, Byeon;Kwang-il, Cheon
    • Journal of Environmental Impact Assessment
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    • v.31 no.6
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    • pp.388-408
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    • 2022
  • This study was conducted to select the indicator species (plant) according to the topographical characteristics in the Picea jezoensis forests, endangered subalpine coniferous trees. In South Korea and China (close to Baekdusan), the southern tree line limit of Picea jezoensis has meaningful geographical and latitudinal values for analyzing the ecological characteristics of P. jezoensis forests. Latitude greatly affects the geographical values of plant ecology, and the difference in latitude and habitat affects the change in species composition in forests. With prolonged environmental change, the habitat of subalpine plants will become smaller, and the plants may become extinct. As the P. jezoensis forests of South Korea and China, in particular, are in danger of disappearing without protection, it is important to monitor the population and develop a conservation strategy. Eighty-seven circular plots were established in P. jezoensis forests in South Korea and China. Through processes such as MRPP-test and NMS ordination, indicator species were selected based on this, and basic data for biodiversity assessment were presented. As a result of the Indicator Species Analysis (ISA), 5 taxa were selected from the upperstory vegetation and 18 taxa from the understory vegetation at the altitude(p<0.05). Indicator species by aspect were analyzed as 3 taxa for upperstory vegetation and 16 taxa for understory vegetation (p<0.05). In the case of indicator species according to the slope, 6 taxa for upper vegetation and 24 taxa for understory vegetation were selected(p<0.05). As for the indicator species according to their habitat, 8 taxa in upper vegetation and 65 taxa on understory vegetation were selected. As a result of MRPP-test, it was analyzed that the species composition was heterogeneous in the group of understory vegetation than that of upperstory vegetation. As a result of NMS ordination, the correlation with environmental factors of indicator species was analyzed by rock exposure for upperstory vegetation and latitude for understory vegetation (cut off level=0.3).

A review of the mass-mortalities of sea-cage farm fishes (해상 가두리양식장 양식어류의 대량폐사에 대하여)

  • Han, Jido;Lee, Deok-Chan
    • Journal of fish pathology
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    • v.35 no.1
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    • pp.1-25
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    • 2022
  • The aquaculture industry has developed rapidly over the last three decades and is an important industry that supplies over 15% of humans' animal protein intake; therefore, there is a need to increase production to meet the continuous demand. The fish cage farms on the southern coast (Kyengsangnam-do and Jeollanam-do) of Korea are critical resources in aquaculture because they account for approximately 90% of the national total fish cage farms by water area ratio. However, the current aquaculture environment is being gradually affected by climate change, which is a global issue, and its effects are expected to intensify in the future. Therefore, it is urgently imperative to accurately evaluate the effects of climate change on South Korean aquaculture industries and to develop social and national strategies to minimize damage to the fishing industry. The damage to fish farmed in cage farms on the southern coast is increasing annually and the leading causes are high and low water temperature and red tides, which are directly or indirectly related to climate change. At present, global warming can provide opportunities for aquaculture industrialization of fish or other novel species, with economic implications. However, despite such opportunities, the influx of new species can also cause problems such as ecological disturbances, increase in the reproduction frequency of microalgae such as red tide, increase in disease incidence, and occurrence and periods of high water temperatures in summer. The scale of farmed fish mortality is increasing due to the complex effects of these factors. Increased damages due to fish mortality not only have severe economic impacts on the aquaculture industry, but the social costs of responding to the damage and follow-up measures also increase. various active responses can reduce the mortality damage in fish farms such as improving the management skills in aquaculture, improved species breeding, efficient food management, disease prevention, proactive responses, and system-wide improvements. This review article analyzes the large-scale mortality cases occurring in fish cage farms on the southern coast of Korea and proposes measures to mitigate mortality and enhance responses to such scenarios.

Prediction of Acer pictum subsp. mono Distribution using Bioclimatic Predictor Based on SSP Scenario Detailed Data (SSP 시나리오 상세화 자료 기반 생태기후지수를 활용한 고로쇠나무 분포 예측)

  • Kim, Whee-Moon;Kim, Chaeyoung;Cho, Jaepil;Hur, Jina;Song, Wonkyong
    • Ecology and Resilient Infrastructure
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    • v.9 no.3
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    • pp.163-173
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    • 2022
  • Climate change is a key factor that greatly influences changes in the biological seasons and geographical distribution of species. In the ecological field, the BioClimatic predictor (BioClim), which is most related to the physiological characteristics of organisms, is used for vulnerability assessment. However, BioClim values are not provided other than the future period climate average values for each GCM for the Shared Socio-economic Pathways (SSPs) scenario. In this study, BioClim data suitable for domestic conditions was produced using 1 km resolution SSPs scenario detailed data produced by Rural Development Administration, and based on the data, a species distribution model was applied to mainly grow in southern, Gyeongsangbuk-do, Gangwon-do and humid regions. Appropriate habitat distributions were predicted every 30 years for the base years (1981 - 2010) and future years (2011 - 2100) of the Acer pictum subsp. mono. Acer pictum subsp. mono appearance data were collected from a total of 819 points through the national natural environment survey data. In order to improve the performance of the MaxEnt model, the parameters of the model (LQH-1.5) were optimized, and 7 detailed biolicm indices and 5 topographical indices were applied to the MaxEnt model. Drainage, Annual Precipitation (Bio12), and Slope significantly contributed to the distribution of Acer pictum subsp. mono in Korea. As a result of reflecting the growth characteristics that favor moist and fertile soil, the influence of climatic factors was not significant. Accordingly, in the base year, the suitable habitat for a high level of Acer pictum subsp. mono is 3.41% of the area of Korea, and in the near future (2011 - 2040) and far future (2071 - 2100), SSP1-2.6 accounts for 0.01% and 0.02%, gradually decreasing. However, in SSP5-8.5, it was 0.01% and 0.72%, respectively, showing a tendency to decrease in the near future compared to the base year, but to gradually increase toward the far future. This study confirms the future distribution of vegetation that is more easily adapted to climate change, and has significance as a basic study that can be used for future forest restoration of climate change-adapted species.

Feasibility of Environmental DNA Metabarcoding for Invasive Species Detection According to Taxa (분류군별 외래생물 탐지를 위한 환경 DNA 메타바코딩 활용 가능성)

  • Yujin Kang;Jeongeun Jeon;Seungwoo Han;Suyeon Won;Youngkeun Song
    • Journal of Environmental Impact Assessment
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    • v.32 no.2
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    • pp.94-111
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    • 2023
  • In order to establish an effective management strategy for invasive species early detection and regular monitoring are required to assess their introduction or dispersal. Environmental DNA (eDNA) is actively applied to evaluate the fauna including the presence of invasive species as it has high detection sensitivity and can detect multiple species simultaneously. In Korea, the applicability evaluation of metabarcoding is being conducted mainly on fish, and research on other taxa is insufficient. Therefore, this study identified the feasibility of detecting invasive species in Korea using eDNA metabarcoding. In addition, to confirm the possibility of detection by taxa, the detection of target species was evaluated using four universal primers (MiFish, MiMammal, Mibird, Amp16S) designed for fish, mammals, birds, and amphibians. As a result, target species (Trachemys scripta, 3 sites; Cervus nippon, 3 sites; Micropterus salmoides, 7 sites; Rana catesbeiana, 4 sites) were detected in 17 of the total 55 sites. Even in the selection of dense sampling sites within the study area, there was a difference in the detection result by reflecting the ecological characteristics of the target species. A comparison of community structures (species richness, abundance and diversity) based on the presence of invasive species focused on M.salmoides and T.scripta, showed higher diversity at the point where invasive species were detected. Also, 1 to 4 more species were detected and abundance was also up to 1.7 times higher. The results of invasive species detection through metabarcoding and the comparison of community structures indicate that the accumulation of large amounts of monitoring data through eDNA can be efficiently utilized for multidimensional ecosystem evaluation. In addition, it suggested that eDNA can be used as major data for evaluation and prediction, such as tracking biological changes caused by artificial and natural factors and environmental impact assessment.

Impact of Fish Farming on Macrobenthic Polychaete Communities (해상 가두리 양식이 저서 다모류군집에 미치는 영향)

  • Jung, Rae-Hong;Yoon, Sang-Pil;Kwon, Jung-No;Lee, Jae-Seong;Lee, Won-Chan;Koo, Jun-Ho;Kim, Youn-Jung;Oh, Hyun-Taik;Hong, Sok-Jin;Park, Sung-Eun
    • The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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    • v.12 no.3
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    • pp.159-169
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    • 2007
  • Excessive input of organic matters from fish cage farms to the coastal waters has been considered as one of the major factors disturbing their benthic ecosystem. Sediment samples were taken from around the two fish cage zones (A and B) in Tongyeong coast in June and August 2003, to evaluate the ecological impacts of fish cage farming activity on the macrobenthic polychaete communities. Polychaete accounted for $81{\sim}87%$ of the total macrofauna individuals from each of the sampling stations. The number of species, abundance, diversity and dominant species of polychaete were rapidly changed with the distance from the fish cages. Within 10 m from the fish cages, Capitella capitata, which is a bio-indicator for the highly enriched sediments, was a dominant species and the lowest diversity was recorded. In particular, the maximum density (${\sim}18,410\;ind.m^2$) of C. capitata was found at Farm A where fish cages were more densely established within a semi-enclosed bay system. The sampling zone between 10 m and 15 m showed a rapid decrease of C. capitata with a rapid increase of the numbers of species, implying that this zone may be an ecotone point from a highly to a slightly enriched area. In the sampling zone between 15 m and 60 m, a transitional zone, which represents slightly enriched condition before normal one, was observed with additional increase and maintenance of the number of species and density of polychaete. In addition, the potential bio-indicators of organic enrichment, such as Lumbrineris longifolia and Aphelochaeta monilaris were the predominant species in the sampling zone. Multidimensional scaling (MDS) ordination plots and k-dominance curves confirmed the above results on the gradual changes in the macrobenthic polychaete communities. Our findings suggest that the magnitude of impact of fish cage farming activity on polychaete communities is probably governed by a distance from fish cage, density of fish cage and geomorphological characteristics around fish cage farm.

The Study on the Height Characteristics of Abies Nephrolepis Community in South Korea - In the Case of Seorak·Odae·Taebaek National Park - (우리나라 분비나무의 수고 특성 연구 - 설악·오대·태백산국립공원을 대상으로 -)

  • Jin-Won Kim;Ho-Young Lee;Young-Moon Chun;Choong-Hyeon Oh
    • Korean Journal of Environment and Ecology
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    • v.38 no.2
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    • pp.169-177
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    • 2024
  • This study investigated whether population dynamic analysis based on the height characteristics of Abies nephrolepis was feasible. It was necessary because existing population dynamic analyses based on age and diameter at breast height (DBH) made it difficult to reflect the slow growth characteristics of Abies nephrolepis in harsh environments of high altitudes. The limitations of population dynamics analysis based on the age and DBH distribution of Abies nephrolepis in Seoraksan, Odaesan, and Taebaeksan National Parks, where Abies nephrolepis populations are representative, were verified, and the characteristics of height growth were investigated to comprehensively analyze whether a vertical structure based on height could reveal the population dynamics. The result of this study showed some limitations in understanding the population dynamics of Abies nephrolepis based on age distribution due to practical difficulties in sampling all trees and variations in age distribution within the same community depending on factors such as light conditions. Moreover, it was challenging to differentiate the distribution of DBH classes at fine levels, making it difficult to reflect the rapid growth characteristics of Abies nephrolepis when light conditions become suitable after prolonged stays in smaller DBH classes under shade conditions. However, a comprehensive analysis of the height characteristics of Abies nephrolepis revealed that the density corresponding to the population dynamic characteristics of Abies was high and adequately reflected the predominant tree death at similar height stages, as well as the U-shaped population dynamics at the lower stratum. Moreover, it was possible to identify a transition point in height values under shaded conditions, where the annual growth of Abies nephrolepis individuals in the lower stratum increases significantly, indicating that Abies nephrolepis individuals can escape from competition with other shrubs and undergo vigorous growth only at this height level. Therefore, this study confirmed that a vertical structure based on height can be utilized to understand the population dynamics of Abies nephrolepis in high altitudes, and it is expected that future studies on height characteristics can intuitively reveal the maintenance status of Abies nephrolepis populations in the field.

Sexual Size Dimorphism in the Red-tongued viper snake(Gloydius ussuriensis) of Population (쇠살모사 개체군의 성적 크기이형)

  • Kim, Byoung-Soo;Oh, Hong-Shik
    • Korean Journal of Environment and Ecology
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    • v.28 no.5
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    • pp.542-549
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    • 2014
  • This study was conducted to investigate the body size, sexual size dimorphism (SSD), and related environmental factors between Red-tongued viper snakes (Gloydius ussuriensis) inhabiting two different places, i.e., Jeju Island and its islet Gapado, and to provide data required to maintain species diversity from May, 2006 until June, 2009. The snout-vent length of the Red-tongued viper snake population inhabiting Jeju Island was found to be 242-532 mm ($422.0{\pm}46.7mm$, n = 100) in females and 296-580 mm ($434.5{\pm}51.7mm$, n = 63) in males. In contrast, the snout-vent length was observed to be 205-395 mm ($335{\pm}43.6mm$, n = 55) in female and 215-430 mm ($328{\pm}39.4mm$, n = 73) in male Red-tongued viper snakes inhabiting Gapado. These data demonstrated the snout-vent length of both female and male Red-tongued viper snakes on Jeju Island to be larger than those on Gapado (Female t = 17.343, df = 115, P<0.001; Male = 19.128, df = 101, P<0.001). SSD was measured to be -0.03 in the Red-tongued viper snake population on Jeju Island, with more or less larger sizes in the males, while it was 0.02 in the Red-tongued viper snake population in the Gapado, with a little larger sizes in the females. The reason for this difference in the snake populations between Jeju Island and Gapado may be due to adaption to the different ecological environments. In addition, as SSD, the snout-vent length of the Red-tongued viper snake populations and in young vipers was somewhat higher in the males than in the females on Jeju Island (t = -2.011, df = 117, P<0.05). However, no significant differences were observed in the snout-vent length of the young and the general Red-tongued viper snake populations on Gapa Island. For the population on Jeju island, the head length (F = 6.318, $df_{1,2}$=1,117, P<0.05), head width (F=8.090, $df_{1,2}$=1,117, P<0.01), inter eye length (F=15.898, $df_{1,2}$=1,117, P<0.001), and tail length (F=238.488, $df_{1,2}$=1,111, P<0.001) were all larger in the males, while females showed higher body mass (F=64.111, $df_{1,2}$=1,114, P<0.001). In the case of the Gapa Island population, no significant differences in the head length, head width, and inter eye length between females and males were observed, while the males had a longer tail length (F=168.555, $df_{1,2}$=1,74, P<0.001) and the females were heavier (F=17.812, $df_{1,2}$=1,76, P<0.001). Though no significant differences were found in the head length, head width, and inter eye length, the tail length (F=67.793, $df_{1,2}$=1,72, P<0.001) and body mass (F=4.558, $df_{1,2}$=1,72, P<0.05) were higher in the young male Red-tongued viper snakes than in the females. The snout-vent length, head length, head width, and inter eye length, which did not display SSD in the young Red-tongued viper snake populations, were higher in the male Red-tongued viper snake populations than in the female population from Jeju Island, implying that SSD in the Red-tongued viper snake population on Jeju Island is expressed due to environmental effects during their growth.