• Korean Journal of Environment and Ecology
• /
• v.31 no.3
• /
• pp.318-328
• /
• 2017

In order to provide basic data for the ecological management of forest vegetation in Southern Naeyeon Mountains, A total of 149 sample plots were selected and vegetation survey was carried out by the phytosociological method of the ZM school to classify vegetation types and to grasp ecological characteristics. The forest vegetation was divided into 10 types in terms of species composition, and had a unit hierarchy of 2 community groups, 4 communities, 6 sub-communities and 6 variants. A total of 19 types of physiognomic vegetation were identified based on uppermost dominant species, of which 18 were natural vegetation and 1 was artificial vegetation. As a result of the analysis of the importance values of constituent species, Quercus mongolica, a potentially natural vegetation element, was found to be relatively more important in most stands than other species, and excluding the artificial interference, most of the areas except for some sites would be changed to Q. mongolica forest. In order to understand the spatial distribution of forest vegetation, 1/5,000 large-scale physiognomic vegetation map was created by the uppermost dominant species. As a result, natural vegetation accounted for 98.2%, the number of vegetation patches was 733 and the average area per patch 3.93ha.

• Korean Journal of Environment and Ecology
• /
• v.34 no.2
• /
• pp.142-156
• /
• 2020

This study surveyed Gyeongan Stream, a tributary of the Han River Drainage System, from April to October 2017 to investigate the characteristics of fish communities. The survey collected 40 species of 11 families from 48 survey stations using kick nets and cast nets. The dominant and subdominant species were Zacco platypus (48.0%) and Rhynchocypris oxycephalus (17.7%), respectively. The next most abundant species were Pungtungia herzi (6.8%), Z. koreanus (5.0%), Carassius auratus (4.3%), Squalidus gracilis majimae (2.7%), and Rhodeus notatus (2.5%). Among the fish collected, 14 species (35.0%) were Korean endemic species, and the exotic species were Micropterus salmoides, Lepomis macrochirus, and Cyprinus carpio (Israeli type). The land-locked species were Plecoglossus altivelis, Rhinogobius brunneus, and Cottus koreanus, while the species sensitive to climate change was C. koreanus. The community analysis showed that the dominance was higher at the uppermost stream station, whereas diversity and abundance tended to be lower at the upstream station and higher toward the downstream station. The community structure was largely divided into rivers (uppermost stream, upstream, and middle-lower stream) and lake. The river health was mostly good (23 stations, 47.9%) and fair (15 stations, 31.3%). Comparison with past surveys showed that 12 species identified in the past surveys did not appear in this survey; nine species appeared for the first time in this survey; and the ecosystem disturbance species - M. salmoides and L. macrochirus - tended to spread more widely gradually.

• Ocean Science Journal
• /
• v.40 no.4
• /
• pp.221-227
• /
• 2005

The architecture of macrofaunal burrows and the total area of the sediment-water interface created by biogenic structure were investigated in the Donggeomdo tidal flat on the west coast of Korea. Resin casting methods were applied to recover burrows of four dominant species, Macrophthalmus japonicus, Cleistostoma dilatatum, Perinereis aibuhitensis, and Periserrula leucophryna, and whole burrows within the casting area at three sites in different tidal levels. P. leucophryna excavated the largest burrow in terms of a surface area among them. In the case of whole burrow casting, the space occupied by the biogenic structure was extended into deeper and expanded more greatly at the higher tidal level. In the uppermost flat, the burrow wall surface area within sediment was more extensive than the sediment surface area. Increased oxygen supply through the extended interface could enhance the degradation rates of organic carbon and also change the pathways of degradation. Quantifying the relationship between the extended interface and mineralization rate and pathway requires more extensive study.

• Journal of Forest and Environmental Science
• /
• v.32 no.1
• /
• pp.74-81
• /
• 2016

Classified into sub-tree of the growth-form, Acer pseudosieboldianum and Carpinus cordata hardly reach the uppermost canopy with limited height growth potentiality in the natural deciduous forest. However, the two species usually dominate lower stories of the forest, playing an important role in overall ecological characteristics in the forest. Based on the vegetation data of 106 $20m{\times}20m$ sample plots in Mt. Jumbong area, this study was carried out to evaluate ecological constitution by several quantitative analysis so as to understand the mechanism of the natural deciduous forest. The results indicated that individuals of A. pseudosieboldianum and C. cordata were absent or few in overstory, but emerged the most dominant species in midstory and understory, providing adequate proof of the ecological importance. The comparison of indices of succession between presented and predicted values in midstory did not make much difference, suggesting that the species composition would not change much and come close to steady state in midstory and understory. The pair combination of species association noted that A. pseudosieboldianum had significant positive association with C. cordata, Quercus mongolica, and Tilia amurensis had significant positive association with A. pseudosieboldianum, A. pictum subsp. mono and Fraxinus mandshurica but negative association with F. rhynchophylla. Being compared with other major canopy tree species in the study forest, the target species of A. pseudosieboldianum and C. cordata had strong regeneration strategies, partially characterized by large number of saplings and pole sized trees and high ratio of live crown, which indicated high shade tolerance to survive in the limited amount of light under the canopy. Even though A. pseudosieboldianum and C. cordata do not reach and occupy the canopy layer mainly due to the inherent growth form, they would have highest competitive potentiality to prosper and dominate in the midstory of the natural deciduous forest.

• Korean Journal of Ichthyology
• /
• v.27 no.2
• /
• pp.116-132
• /
• 2015

Freshwater fish fauna and community structure were investigated at 44 stations in upper reach of the Nakdong river, Korea from March to October 2014. During the surveyed period 42 species and 4 types belonging to 34 genera and 14 families were collected. In this collection fishes of Cyprinidae were 17 species and 4 types, most numerous possessing 43.2% of all. There were 17 Korean endemic species including Kichulchoia multifasciata, 3 endangered species such as Koreocobitis naktongensis, Lethenteron reissneri and Brachymystax lenok tsinlingensis and 2 exotic species such as Lepomis macrochirus and Micropterus salmoides. Fish species transferred from other native rivers were 9 species including Hemibarbus mylodon, Coreoleuciscus slpendidus Han river type, Opsariichthys uncirostris amurensis, Iksookimia koreensis and Liobagrus andersoni. Dominant species based on the number of individuals was Rhynchocypris oxycephalus (21.44%) and sub-dominant species were Zacco koreanus NE type (18.55%). The community analysis revealed that the structure of fish community in upper reach of the Nakdong river was very stable and diverse in having diversity 1.101, evenness 0.670, dominance 0.400 and species richness 4.454. Fish community was divided into 5 groups based on similarity indices among surveyed stations such as uppermost, upper I, upper II, mid-upper, middle reach group.

• Korean Journal of Environment and Ecology
• /
• v.32 no.2
• /
• pp.154-164
• /
• 2018

We investigated the ichthyofauna and fish community structure of the Mudeungsan National Park, Korea from 2014 to 2016 to prepare a conservation plan. We collected 21 species of 6 families collected from 8 survey stations through skimming nets and cast nets during the period. The dominant and subdominant species were Zacco temminckii (43.0%) and Rhynchocypris oxycephalus (15.1%), respectively. The other abundant species were Z. platypus (11.2%), Pungtungia herzi (10.1%), Squalidus gracilis majimae (8.9%), and Z. koreanus (4.5%). Among the fish collection, 13 species (61.9%) were Korean endemic species, but, endangered species and exotic species were not found. Similarity indices based on species composition and abundance showed the clear division of the fish community into two river systems (Yongsan River drainage system (St. 1-7) and Seomjin River drainage system (St. 8)). The Youngsan River system was further divided into the uppermost (St. 1, 2, 4, 6, and 7) and the upper-middle (St. 3 and 5) regions. The number of species appearing in a year was similar at 19 to 20 throughout the survey period. However, the individual number of fish in 2015 (2,670) was 20% less than that of 2014 (3,366) and 2016 (3,429), respectively. The probable reason for this decline is the rapid decline of stream level in 2015 compared to the other years. During the survey period, river works were undergoing at 3 out of 8 stations, having created disturbance in fish habitat and especially impacted on benthic fishes.

• Korean Journal of Environment and Ecology
• /
• v.35 no.3
• /
• pp.265-276
• /
• 2021

This study investigated the characteristics of fish communities and river health in the Sincheon stream of Imgin River between April and October 2019. The survey collected 3,677 objects in 30 species belonging to 12 families from 23 survey stations. The dominant and subdominant species were Zacco platypus (28.4%) and Oryzias sinensis (13.6%), respectively, followed by Z. koreanus (11.8%), Rhynchocypris oxycephalus (11.7%), Carassius auratus (9.6%), and Pseudorasbora parva (7.9%) in that order. Among the fish species collected, 10 (33.3%) were endemic species in Korea. The exotic species were 5 (16.7%), including Micropterus salmoides, Lepomis macrochirus, Cyprinus carpio (Israeli type), Poecilia reticulata, and Xiphophorus maculatus. The land-locked species included Cottus koreanus and Rhinogobius brunneus, while C. koreanus was a climate change-sensitive species. The dominance of the fish community was low, and the diversity was high in the Sincheon mainstream, Sudongcheon and Cheongdamcheon, whereas Dongducheon and Sangpaecheon showed higher dominance and low diversity. The river health was very good and good in the uppermost and Sudongcheon areas, whereas the upper stream was normal, and the middle and lower streams were poor and very poor, respectively. The water quality was also mostly poor or very poor from the midstream to the downstream, and only Sudongcheon was very good. Therefore, the water quality had a great impact on fish habitat and eventually affected river health significantly. Although the water quality of Shincheon has improved each year, the introduction of several foreign species had a very negative effect. Improvement of river health in Shincheon requires water quality improvement and management of exotic fish species.

• Korean Journal of Environment and Ecology
• /
• v.34 no.6
• /
• pp.530-542
• /
• 2020

This study surveyed the central mountain area of Demilitarized Zone (DMZ) from March to October 2018 to reveal the appearance patterns of freshwater fish. We collected 7,744 individuals of 43 species in 12 families with skimming nets and cast nets in 12 stations during the survey. The dominant species was Zacco koreanus (30.3%), and the subdominant species was Z. platypus (18.5%), followed by Rhynchocypris oxycephalus (10.0%), R. steindachneri (6.7%), Microphysogobio yaluensis (5.9%), Acheilognathus signifer (4.5%), Pungtungia herzi (4.2%), and Orthrias nudus (2.6%). Among the collected species, four were legally protected. They included Hemibarbus mylodon, which was a natural monument, and Lethenteron reissneri, A. signifer, and Pseudopungtungia tenuicorpa, which were class II endangered wildlife designated by the Ministry of Environment. Twenty Korean endemic species (46.5%) and one exotic species, Micropterus salmoides, were also collected. Additionally, three climate-change sensitive species, R. kumgangensis, Ladislavia taczanowskii, and Cottus koreanus, and three landlocked species, L. reissneri, C. koreanus, and Rhinogobius brunneus appeared. The dominant species in each station were Z. koreanus (15 stations), Z. platypus (four stations), R. oxycephalus (four stations), and C. koreanus (one station). The species dominance index decreased from upstream to downstream (mainstream of Gimhwanamdae Stream), while the species diversity index and the species richness index increased. The community structure of the rivers was divided into the uppermost stream, upper stream, Han River, and Imjin River. Compared to antecedent surveys, this study collected the highest number of species. Two new species (Sarcocheilichthys variegatus wakiyae and Micropterus salmoides) were caught, while six species (Siniperca scherzeri, Leiocassis ussuriensis, Brachymystax lenok tsinlingensis, Rhodeus ocellatus, Abbottina springeri, Aphyocypris chinensis) did not appear. Gimhwanamdaecheon Stream has high biological value with the inhabitation of many species, including species under legal protection and high diversity and richness index scores. This paper also discussed a protection plan for this area.

• Korean Journal of Ecology and Environment
• /
• v.46 no.3
• /
• pp.460-470
• /
• 2013

Forest vegetation of Choksangsan area in the Deogyusan National Park is classified into mountain forest vegetation. Mountain forest vegetation is subdivided into deciduous broad-leaved forest, valley forest, coniferous forest, afforestation and other vegetation. Including 103 communities of mountain forest vegetation and 8 communities of other vegetation, the total of 111 communities were researched; the mountain forest vegetation classified by physiognomy classification are 36 communities deciduous broad-leaved forest, 26 communities of valley forest, 10 communities of coniferous forests, 31 plantation and 8 other vegetation. As for the distribution rate for surveyed main communities, Quercus mongolica, Quercus variabilis communities account for 65.96 percent of deciduous broad-leaved forest, Fraxinus mandshurica community takes up 22.50 percent of mountain valley forest, Pinus densiflora community holds 63.27 percent of mountain coniferous forest holds. In conclusion, minority species consisting of Quercus mongolica, Fraxinus mandshurica, Quercus serrata, Pinus densiflora, and Quercus variabilis are distributed as dominant species of the uppermost part in a forest vegetation of Choksangsan in Deogyusan National Park. In addition, because of vegetation succession and climate factors, numerous colonies formed by the two species are expected to be replaced by Quercus mongolica, Carpinus laxiflora and Fraxinus mandshurica which are climax species in the area.

• Korean Journal of Environment and Ecology
• /
• v.31 no.2
• /
• pp.188-201
• /
• 2017

Based on a total of 272 vegetation data collected by the ZM school phytosociological study method, the composition and structural characteristics of the forest vegetation in the Sogwang-ri forest genetic resource reservoir located in Uljin-gun, Gyeongsangbuk-do were compared using the table comparison method and the TWINSPAN method, And their ecological characteristics were analyzed. The types of forest vegetation were classified into 7 types, and it was divided into two major groups, 'Slope and Ridge type', which characterized by Quercus mongolica, Pinus densiflora for. erecta, Lespedeza bicolor etc. and 'valley and concave slope', which characterized by Cornus controversa, Fraxinus mandshurica, Morus bombycis, Hydrangea serrata for. acuminata etc. The hierarchy of the vegetation unit was 2 community groups, 4 communities, and 6 subcommunities. The structural characteristics such as the total percent cover, species importance value, species diversity of the constituent species per unit area($/100m^2$) of each type of forest vegetation were also identified. In order to understand the spatial distribution of forest vegetation, 1/5,000 large-scale physiognomic vegetation map was created by the uppermost dominant species. The composition and structural characteristics of Geumgang pine(P. densiflora for. erecta) forest, which is a core community of protected area by natural and anthropogenic influences, appear as a subtype of Quercus mongolica forest, which is a potential natural vegetation, Appropriate maintenance measures seemed urgently needed.