• Journal of the Korean Institute of Traditional Landscape Architecture
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• v.35 no.2
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• pp.77-86
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• 2017

A study on the population ecology of gregarious Wisteria habitat was conducted in Beomeosa temple, Busan. The area has been protected since it was designated as No. 176 natural monument in 1966. Such a large habitat of native wisteria (Wisteria floribunda DC.) in Korea is very rare so that it has a very high academic value. However, there are no high-resolution researches on the distribution and ecology of wisteria in the Gregarious Wisteria Habitat of Beomeosa Temple. The study aimed to identify the distribution and characteristics of wisteria populations in the Wisteria habitat. The study identified the distribution of Wisteria, RCC, the climbing direction, the plant and flora in the research area in the Gregarious Wisteria Habitat of Beomeosa Temple in Busan and the surrounding areas based on an on-site research. As a result, the total number of the wisteria populations in the research area was confirmed to be 1,158 and the RCC of wisteria was on average 69.0 mm (${\pm}45.5$) and in maximum 365 mm. In terms of the climbing direction, the number of wisteria that climbs clockwise or counterclockwise was determined to be 40. It was identified that there are 28 taxa of the climbing plant species and the wisteria of the same kind was the most favorable. The populations were found to be dispersed adjacent to the valleys, and were found to be maintained by constant disturbance. 76.6 % of the population was found to be distributed in the valley forest, and the Carpinus tschonoskii-Pseudosasa japonica forest, Pueraria lobata community and Pinus densiflora forest were found to be relatively dispersed. The study proposed to conduct the follow-up researches to preserve the wisteria that is spreading in this research area, the wisteria with the highest RCC and regional habitat through continuous monitoring; and maintain the protection area of No. 176 natural monument; and discussed the management measures and approaches that reflect the habitat.

• Economic and Environmental Geology
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• v.3 no.1
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• pp.25-34
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• 1970

Very few articles are available on geologic structure and genesis of Sangdong scheelite-deposits in spite of the fact that the mine is one of the leading tungsten producer in the world. Sangdong scheelite deposits, embedded in Myobong slate of Cambrian age at the southem limb of the Hambaek syncline which strikes $N70{\sim}80^{\circ}W$ and dips $15{\sim}30^{\circ}$ northeast, comprise six parallel veins in coincide with the bedding plane of Myobong formation, namely four footwall veins, a main vein, and a hangingwall vein. Four footwall veins are discontinuous and diminish both directions in short distance and were worked at near surface in old time. Hangingwall vein is emplaced in brecciated zone in contact plane of Myobong slate and overlying Pungchon limestone bed of Cambrian age and has not been worked until recent. The main vein, presently working, continues more than 1,500 m in both strike and dip sides and has a thickness varying 3.5 to 5 m. Characteristic is the distinct zonal arrangement of the main vein along strike side which gives a clue to the genesis of the deposits. The zones symmetrically arranged in both sides from center are, in order of center to both margins, muscovite-biotite-quartz zone, biotite-hornblende-quartz zone and garnet-diopside zone. The zones grade into each other with no boundary, and minable part of the vein streches in the former two zones extending roughly 1,000 m in strike side and over 1,100 m in dip side to which mining is underway at present. The quartz in both muscovite-biotite-quartz and biotite-hornblende-quartz zones is not network type of later intrusion, but the primary constituent of the special type of rock that forms the main vein. The minable zone has been enriched several times by numerous quartz veins along post-mineral fractures in the vein which carry scheelite, molybdenite, bismuthinite, fluorite and other sulfide minerals. These quartz veins varying from few centimeter to few tens of centimeter in width are roughly parallel to the main vein although few of them are diagonal, and distributed in rich zones not beyond the vein into both walls and garnet-diopside zone. Ore grade ranges from 1.5~2.5% $WO_3$ in center zone to less than 0.5% in garnet-diopside zone at margin, biotite-hornblende-quartz zone being inbetween in garde. The grade is, in general, proportional to the content of primary quartz. Judging from regional structure in mid-central parts of South Korea, Hambaek syncline was formed by the disturbance at the end of Triassic period with which bedding thrust and accompanied feather cracks in footwall side were created in Myobong slate and brecciated zone in contact plane between Myobong slate and Pungchon limestone. These fractures acted as a pathway of hot solution from interior which was in turn differentiated in situ to form deposit of the main vein with zonal arrangement. The footwall veins were developed along feather cracks accompanied with the main thrust by intrusion of biotite-hornblende-quartz vein and the hangingwall vein in shear zone along contact plane by replacement. The main vein thus formed was enriched at later stage by hydrothermal solutions now represented by quartz veins. The main mineralization and subsequent hydrothermal enrichments had probably taken place in post-Triassic to pre-Cretaceous periods. The veins were slightly displaced by post-mineral faults which cross diagonally the vein. This hypothesis differs from those done by previous workers who postulated that the deposits were formed by pyrometasomatic to contact replacement of the intercalated thin limestone bed in Myobong slate at the end of Cretaceous period.

• Journal of the Korean Institute of Traditional Landscape Architecture
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• v.37 no.2
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• pp.20-29
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• 2019

The purpose of this study is to verify and reconstruct the record information for big old trees of Jeju on the basis of the precise map of Jeju island in 1918 which was produced 100 years ago. For the analysis of high altitude, coordinate system and georeferencing were performed by selecting representative points using ArcGIS. We extracted digitized information by using point extraction method and extracted attribute information based on legend type and relative size in map. Based on the map of the past 100 years ago, the present situation of the big old tree in Jeju was analyzed and their characteristics were analyzed. In addition, based on the information of the protected big old trees in present, we discussed the characteristics of past tree (1918), present tree (2019), and contribution of big old tree in Jeju landscape and vegetation. As a result, 1,013 individuals were distributed in Jeju Island 100 years ago. Even when it was intensive in the use of timber, the big old trees were protected, and contributed as a representative component of Jeju's unique landscape. The remaining distribution of Jeju's big old tree is 159 trees. As in the past, distribution has been confirmed around the lowlands, but declines in numbers are found throughout the island. The major factors for the decline of individuals are large-scale development projects such as reaching the limit of life, natural disturbance (typhoon, disease, pest, drought, etc.). However, it is presumed that a large number of individuals have played a leading role in shaping the current forests as contributing to important species sources in the restoration process of Jeju vegetation. However, it is presumed that a large number of individuals (405) have played a leading role in forming the present forest by contributing to the species pool in the restoration process of Jeju vegetation.

• Korean Journal of Environment and Ecology
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• v.33 no.5
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• pp.578-586
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• 2019

The purpose of this study was to investigate the change of spatial distribution of Korean red pine (Pinus densiflora Siebold & Zucc.) in Hallasan National Park by surveying the distribution and crown density and analyzing by the elevation, slope, orientation, and regional habitat in 2006 and 2015. The total area of the Korean red pine forest was 1,259.9 ha in 2015, which increased by 51.4 ha, or 4.1%, compared to 1,208.5 ha in 2006. For the past 10 years, the area of sparse density with crown density of 11% to 40% of Korean red pine increased by 59.8 ha, the area of moderate density with crown density of 41% to 70% increased by 59.0 ha, and the area of dense density with 71% or more crown density increased by 67.3 ha. In terms of the altitude above sea level, the Korean red pine forest area between 1,010 m and 1,400 m was the largest at 1,003.0 ha or 79.6% of the total area in 2015. The area between 1,100 m and 1,300 m increased, and the area of dense density decreased significantly while the areas of moderate density and sparse density increase. There was no notable change according to the land slope, and the area increased from 2006 regardless of the slope. By direction, 56.4% were distributed in the southwest and southeast directions centered on the south-facing slope with the increase of 27.8 ha over the 10 years while the northwest and northeast directions centered on the north-facing slope decreased by 7.6 ha. Regarding the distribution change of the Korean red pine forest by the region, the Yeongsil area showed an increase of 25.5 ha, or 49.6% of the total area increase, in 2006 while the Ibseog-oreum area including the right side on the Sanbeoleum mountain valley increased by 20.4 ha. The distribution in the Gaemideung area that includes Jogeundeule increased by 7.4 ha while that of Sogbat in Sungpanak Trail decreased by 1.9 ha. This study analyzed the changes in the distribution area and crown density of the Korean red pine forest according to the altitude, slope, direction, and regional habitat in Hallasan National Park. The expansion of Korean red pine forest distribution was limited to the areas where the grass and the shrub was the dominating vegetation structure, or the forest gap was created by the disturbance. On the other hand, the distribution area of the Korean red pine forest surrounded by deciduous broad-leaved forests or mixed vegetation structure is considered to result from the change in density more than the area due to competition with deciduous broad-leaved trees.

• Korean Journal of Environment and Ecology
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• v.35 no.1
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• pp.48-67
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• 2021

Plant species exhibit current characteristics as a result of interactions with environmental conditions. The plants of Viola sp. have selected chasmogamous flowers with vigorous vegetative propagation or development of cleistogamous flowers as an adaptation strategy. Viola websteri is distributed on the Korean peninsula and the eastern part of Jilin Province, China. The center and edge of the distribution are expected to exhibit different population-dynamics. It is necessary to investigate the cause of its current limited distribution even though V. websteri has a mixed-mating strategy. Firstly, We examined the vegetation environment of habitats and evaluated its characteristics. Growth characteristics were examined through plant phenology. We then evaluated the population structure, characteristics of chasmogamous flowers, and productivity of cleistogamous flowers. Moreover, we compared population sizes between 2014 and 2018. Most habitats were located in deciduous broadleaf mixed forests adjacent to valleys. V. websteri produced chasmogamous flowers with self-incompatibility in April-May and cleistogamous flowers in June-September. The cleistogamous flower production is a strategy ensuring seed production under uncertain environmental fluctuations; these were approximately twice as numerous as chasmogamous flowers. The population structure was distinguished into stable and very unstable regions. There were sites where the population experienced a sharp decline in the 2018 compared to that of 2014. This large decline was found in the edge populations. The habitats had different microsites depending on the natural disturbances of drought and the matrix constituting the habitat, thus supporting various plants. Ensuring the production of seeds through cleistogamous flowers, it was determined that rapid seedling re-establishment and population replenishment were possible when the natural disturbance factor was removed. Environmental factors did not equally affect all populations or individuals. Therefore, it was expected that it would be able to persisted in a long time, despite the rapid decrease in the number of individuals in the population regionally. Local extinction and re-establishment are likely to repeat according to environmental change. We propose the additional population investigation based on this works are required. We also suggest a need to assess the long-term population dynamics and the genetic characteristics of chasmogamous flowers and cleistogamous flowers to establish and implement effective conservation strategies.

• Korean Journal of Environment and Ecology
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• v.36 no.4
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• pp.368-380
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• 2022

Biomonitoring of an invasive alien crayfish species, Procambarus clarkii (Girard, 1852), was performed from February to October 2021, along with environmental DNA analysis, at five locations including Wanju-gun, Hampyeong-gun, Naju-si, Gurye-gun, and Cheongju-si. For the investigation, an umbrella-shaped trap for adults and a hand net for young crayfish were used, and 8 to 10L of freshwater was collected for eDNA analysis. The current status and past distributional records of crayfish in Korea were analyzed along with benthic macroinvertebrates at each survey site. As a result of the investigation, a total of 122 individuals were identified, and Hampyeong-gun recorded the largest number of populations with 59 individuals (48.36%) and the highest environmental DNA (eDNA). The frequency of appearance of P. clarkii was highest in May. The ratio of females to males was 21:5, and the body size was 72.2±21.1mm for female, 80.5±15.6mm for male, and 25.3±9.8mm for young crayfish. P. clarkii introduced into Korea is mainly spreading in the southwest region and it has not been observed in Seoul where there had been a record of appearance in the past. No external symbiosis (Branchiobdellida) of P. clarkii has been identified, and P. clarkii that has appeared in Korea was presumed to be imported from Japan. There are more than eight kinds of exotic crayfish distributed in Korea, and among them, the marbled crayfish (P. virginalis) was identified as a harmful species to the ecosystem of Korea by the Ministry of Environment in 2021. The identified species of benthic macroinvertebrates inhabiting the survey area where P. clarkii has appeared were 69 belonging to 39 families, 15 orders, five classes, and three phyla. Among them, Odonata were the most abundant (16 spp.; 24.62%), followed by Coleoptera (11 spp.; 16.92%) and Hemiptera (11 spp.; 16.92%). In the survey area, one Korean endemic species (Rhoenanthus coreanus), one species (Helophorus auriculatus) classified as Near Threatened (NT) on the Korean Red List, and six species of Crustaceans appeared. In the functional feeding group, the predators appeared predominantly while in habitat oriented group, the climbers appeared to be abundant. It was confirmed that P. clarkii in the survey area prefers an area rich in aquatic vegetation with waterside vegetation, and has high resistance to turbid water quality. The omnivore invader P. clarkii is expected to maintain a competitive relationship with carnivorous benthic macroinvertebrates that are predominant in the same species, and is expected to continue to generate ecosystem disturbance along the food chains.