• Korean Journal of Environment and Ecology
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• v.18 no.3
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• pp.306-315
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• 2004

Yangjae stream, stretching through Seocho-gu and Gangnam-gu, is a representative city stream with its environmentally friendly stream makeover project model, launched in 1995. The district of Gangnam-gu, the subject of this study, is under high pressure from the residents for its use as a huge residential areas close to the stream. The study has two main purposes. The first is to identify the condition and characteristic of utilization of Yangjae stream which is currently being increased in use by the stream restoration. Secondly, the study aims to suggest the environment-friendly management to accomplish arrangement of the naturally friendly stream based on the identification survey, The result from the user survey with 303 valid answer sheets show that the people from neighboring residential areas use this stream a lot doing exercising(51.8%) and taking a walk(24.4%) in their free time. Also regular use rate is high, and people are likely to use it alone(30.4%) or as a family(28.4%). With regard to the need of facility increase, even though the respondents required resting places in the shade(80.8%) most, overall, additional introduction of facilities was analyzed as unnecessary(78.8%). safety issue(22.0%) and a lack of convenience facilities(17.6%) and resting places in the shade(16.6%) are pointed as main problems while the users are generally satisfied(59.5%) with the stream. Improving walk-way and planting trees for shade on the slope were designed as a solution for these problems. For securing safety through improvement of walk-way, the scattering of pressure of current walk with building new walk using berms was presented. In order to increase safety on the walk-way(see above figure), the study proposes to build a new walk-way with berms to disperse excessive pressure. It also suggests the tree planting to provide shade in the stream and to make a provision for the planting of forest trees in the current law.

• International Journal of Highway Engineering
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• v.1 no.1
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• pp.107-119
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• 1999

The joints in the jointed concrete pavement provide a control against transverse or longitudinal cracking at slab, which may be caused by temperature or moisture variation during or after hydration. Without control of cracking, random cracks cause more serious distresses and result in structural or functional failure of pavement system. However, joints nay cause distresses due to its inherent weakness in structural integrity. Thus, the evaluation at joint is very important. and the joint-related distresses should be evaluated reasonably for economic rehabilitation. The purpose of this paper was to develop an evaluation system at joints of jointed concrete pavement using finite element analysis program, ILLI-SLAB, and nondestructive testing device. FWD. To develop an evaluation system for JCP, a sensitivity analysis was performed using ILLI-SLAB program with a selected variables which might affect fairly to on the performance of transverse joints. The most significant variables were selected from precise analysis. An evaluation charts were made for jointed concrete pavement by adopting the field FWD data. It was concluded that the variables which most significantly affect to pavement deflections are the modulus of subgrade reaction(K) and the modulus of dowel/concrete interaction(G), and limiting criteria on the performance of joints at JCP are 300pci. 500,000 lb/in. respectively. Using these variables and FWD test, a charts of load transfer ratio versus surface deflection at joints were made in order to evaluate the performance of JCP. Practically, Chungbu highway was evaluated by these evaluation charts and FWD field data for jointed concrete pavement. For Chungbu highway, only one joint showed smaller value than limiting criterion of the modulus of dowel/concrete interaction(G). The rest joints showed larger values than limiting criteria of the modulus of subgrade reaction(K) and the modulus of dowel/concrete interaction(G).

• Journal of Korean Society of Forest Science
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• v.81 no.1
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• pp.53-65
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• 1992

For elucidating effective methods of restoration of forest recreational sites where management goals are maintaining naturalness and conserving natural ecosystem, seeding, fertilization and soil surface treatment were used for four years at the devastated forest-floor. For restoration of forest-floor vegetation, factorial experiment was used with a split plot design(main plot : fertilization, subplot : soil surface${\times}$seeding) and a randomized complete block design (fertilization${\times}$seeding) at the Kwanaksan Aboretum, Anyang, Kyonggido. Results were summarized as follows : Soil surface softening with tipping and ripping and straw-mat mulching (70% coverage) treatment was effective on germination, survival and growth of seeded vegetation at devastated forest-floor. Especially, straw-mat mulching treatment was effective on soil surface stabilization and seedling's survival at eroded soil surface, while complete soil surface softening treatment was effective on germination, survival and early growth of tree species of late-successional series. Introducing seeds of native species of pioneer or early-successional series, with good growth capability in barren soil was effective on rapid restoration in devastated forest-floor with its soil surface previously compacted and its surviving seeds washed away. When the seeding and straw-mat mulching after partial soil surface softening with tipping and ripping treatment were employed, it took about three years to restore the devastated forest-floor where surface erosion had been undertaken for an extended period of time and where naturally surviving seeds of native species had been washed away. Softening treatment of soil surface was effective for about two years, and seeding and soil surface treatment increased number of seedlings and improved soil surface environment through fixing of movement of the fallen leaves. Fertilizing effect was not oberserved, mainly due to seeding exposure and poor physical condition including soil surface erosion, low soil water potential and drought, etc, at the field experimental site. However, application of nitrogen and phosphate fertilizers was effective on seedling survival of the species in late-successional series, while lime application adversely affected the seedling survival.

• Korean Journal of Environment and Ecology
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• v.36 no.5
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• pp.445-459
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• 2022

In this study, we investigated current vegetation and assessed the health of vegetation through the KERVI (Korea Estuary Riparian Vegetation Index) to monitor vegetation changes near estuaries due to the opening of the Nakdong River estuary. As the first investigation of the long-term monitoring, six areas near the Nakdong River estuary were surveyed twice in July and October 2021, and vegetation monitoring and a survey of species composition and distribution density of aquatic, riparian, and land plants were carried out. The survey identified 262 taxa, 82 families, 192 genera, 196 species, 3 subspecies, 26 varieties, and 1 form of vascular plants in the surveyed area. The results of the vegetation health assessment through KREVI showed that sites 1 and 6 were rated "Very good" in both surveys, sites 2 and 4 were rated "Very good" in the first survey and then "Good"in the second survey, and site 3 and 5 were rated one grade higher in the second survey than the first survey. The assessment showed that the health grades of most species in the survey area were generally high. Most of the potential natural vegetation after the opening of estuary gates to create a brackish water area is expected to consist of reed (Phragmites communisTrin.) communities. The area of the willow (Salix koreensisAndersson) community adjacent to the water area may be somewhat narrower, but the community will be maintained. In the case of freshwater areas in inland areas with very low salinity, reeds (Phragmites communisTrin.) are expected to occupy most of them, and some communities such as amur silver-grass (Miscanthus sacchariflorusBenth.) and cattails (Typha orientalisC. Presl) are expected to be distributed. We suggest establishing measures such as estuary gate operation to create healthy brackish water regions through long-term monitoring.

• Korean Journal of Environment and Ecology
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• v.33 no.3
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• pp.280-291
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• 2019

A. antiquum, first observed in Jeju Samdo Island in 1949, was designated as the Natural Monument No. 18 in December 1962 in recognition of its academic value. In Korea, it grows in nature only in Samdo in Jeju Island. Although its natural habitat was greatly damaged and almost destroyed due to firewood, stealing, etc. After the emancipation, it has been maintained by the transplantation and restoration. The site observed by this study has been managed as a restricted area since 2011. Since it has been about 20 years since the restoration of the native site in the 2000s, it is necessary to check the official management history records, such as the origin of transplantation and restoration to monitor the changes in the growth status and to control the habitat. As the results of this study, we have secured the records of cultural property management history, such as the identification of native species and the transplantation and restoration records. We also examined the change of the growth and development of A. antiquum 20 years after the restoration. There are no official records of the individuals transplanted to the restored natural habitat of A. antiquum in the 1970s and 1980s, and there was a controversy about the nativeness of those individuals that were restored and transplanted in 1974 since they were Japanese individuals. The studies of identifying native as the results of this study, we have secured the records of cultural property management history, such as the identification of native species and the transplantation and restoration records. We also examined the change of the growth and development of A. antiquum 20 years after the restoration. There are two sites in natural habitat in Samdo Island. A total of 65 individuals grow in three layers on three stone walls in a site while 29 individuals grow in two columns in the other site. A. antiquum grows in an evergreen broad-leaved forest dominated by Neolitsea sericea, and we did not find any other individuals of naturally growing A. antiquum outside the investigated site. This study checked the distribution of A. antiquum seedlings observed initially after the restoration. There were more than 300 seedling individuals, and we selected three densely populated sites for monitoring. There were 23 A. antiquum seedlings with 4 - 17 leaves per individual and the leaf length of 0.5 - 20 cm in monitoring site 1. There were 88 individuals with 5 - 6 leaves per individual and the leaf length of 1.3 - 10.4 cm in monitoring site 2 while there were 22 individuals with 5 - 9 leaves per individual and the leaf length of 4.5 - 12.1 cm in monitoring site 3. Although the natural habitat of A. antiquum was designated as a restricted public area in 2011, there is a high possibility that the habitat can be damaged because some activities, such as fishing and scuba diving are allowed. Therefore, it is necessary to enforce the law strictly, to provide sufficient education for the preservation of natural treasures, and to present accurate information about cultural assets.

• Journal of the Korean Institute of Landscape Architecture
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• v.37 no.2
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• pp.1-13
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• 2009

The purpose of this study was to look into the feasibility of site suitability focused on the potential for environmentally- and water-friendly recreation area development in a wide area(Nakdong River 35km) and to study new methods for providing basic data in regard to the recreation planning over a wide area as well as in application to other sites. The results of this study are as follows. Through classification by mesh method, the site of this study was classified into 42 grids, and by means of the analysis of evaluation indicators, 20 indicators were established and sorted into 4 types of significant recreation activity. According to the results of the analysis for each recreation activity type, there were 8 essentials for water-friendly recreation activity types based on water use while water-friendly recreation types for static activity included 12 sub-essentials. As a result of the first evaluation(the minimum required evaluation) by each classified grid, 32 of the 42 total grids were implemented by the minimum requirements. These grids were usually distributed evenly through the whole site. In terms of the second evaluation(specific site evaluation) results, 6 grids were highly suitable for recreational nature experiences and landscape ecological learning, 4 grids for developing water-friendly recreation for exercise, 1 grid for building water-friendly recreation based on water use, and 4 grids for planning water-friendly recreation for static activity. The results of the grid evaluation of this study could be extended to contiguous grids or reduced. Actual planning for a water-friendly recreation area must change the grid shape or size through boundary adjustments.

• Korean Journal of Ecology and Environment
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• v.33 no.4 s.92
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• pp.336-341
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• 2000

This study was conducted to clarify the habitat characteristics and distribution of seagrass. Zostera marina L. (Zosteraceae) in the brackish Hwajinpo Lake, Korea in June 1998 and July 2000. Z. marina beds were distributed along the sea-side cost of the lower lake mouth at 0.8 to 1.5m in death, and the seagrass bed area was about 3,200 m$^{2}$. Salinity, water temperature and pH were in the range of 8.0${\sim}$23.0$%_{o}$, 22.0${\sim}$23.7$^{\circ}C$ and 8.34${\sim}$8.62, respectively. Nutrient concentrations were generally now (TN: 24.34 ${\mu}$M, NH$_{4}$-N: 2.57 ${\mu}$M, NO$_{3}$-N: 0.56 ${\mu}$M, NO$_{2}$-N: 0.27 ${\mu}$M, TP: 2.08 ${\mu}$M, PO$_{4}$-P: 0.34 ${\mu}$M). Suspended particulate matters (SPM) concentration averaged 62.8 mg/l and particulate organic matter (POM) averaged 21.3 mg/l. Organic content of SPM averaged 33.9%. The beds substratum was composed of well-sorted, fine sand and its mean brain size was 3.13${\Phi}$. The Z. marina vegetation was almost submerged, and the morphological characteristics can be classified as steno-leaf phenotype by the shoot length, leaf width, and number of leaf vein. Shoot length and leaf width were 70.0${\sim}$126.5 cm and 5${\sim}$7 mm, respectively. Shoot densities ranged from 264 to 296/m$^{2}$, and the plants biomass was estimated at 332.6 to 373.0 g dw/m$^{2}$. Therefore, the habitats of Z. marina in Korea were recognized in a brackish lake, and morphological characteristics appeared to be variable.

• Journal of the Korean Institute of Traditional Landscape Architecture
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• v.32 no.3
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• pp.69-81
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• 2014

Herman $F{\ddot{u}}rst\;P{\ddot{u}}ckler-Muskau$ is one of important figures in German landscape architecture who designed both Muskau Park and Branitz Park and published garden book Andeutungen ${\ddot{u}}ber$ Landschaftgartenerei (Hints on Landscape Gardening) in 1834. He was a German nobleman who governed Muskau estates while working as both a writer and a landscape gardener. German landscape gardening was grounded on Romanticism, which was represented in diverse ways such as the reconciliation between man and nature, the liberation of reason, and the pursuit of liberty. The intellectuals came to have an interest on landscape gardening since the garden carried the cultural connotation such as the idealized epitome of nature. This study is to investigate how his idea of landscape gardening had been developed through his personal life and social background and to find out his landscape gardening theory and its unique gardening techniques. Finally, the inventive aspect of his garden theory and contemporary significances in practices were discussed. $P{\ddot{u}}cklers^{\prime}$ personal experience and social background provide us to understand the idea of garden. First, there was a mixture between reality and fantasy in his garden theory. It was due to the influence of Romanticism and literary garden. Second, his gardening mentality and technique were influenced by the late 18th century English garden practices, which emphasized the expressive aspects. Third, $P{\ddot{u}}cklers^{\prime}$ inner disposition and personal experience were represented in his garden design. Fourth, the intention of creating landscape garden for the local people might be a self realization of his contradictory characters between falling nobleman and liberal social leader. The significant value of $P{\ddot{u}}ckler^{\prime}s$ garden idea might be closely related in the dual nature of humanistic garden tradition and garden practice for social agenda. Therefore, his garden idea pursued of the comprehensive landscape strategies toward ideal communities and ethical spirits while concerning ecological, social, economic sustainable development of the region. Furthermore, his landscape gardening aims at the total landscape encompassing garden to region as well as the Gesamtkunst combing the beautiful with the useful. $P{\ddot{u}}ckler^{\prime}s$ holistic attitude gives us fresh insights and new directions to contemporary landscape theory and practice.

• Journal of Ecology and Environment
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• v.29 no.6
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• pp.511-520
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• 2006

The study analyzed the distribution of mammalia per altitude in Gamebong, the highest trail of Juwangsan National Park and confirmed the inhabitation of 22 different species inhabiting in the park. Starting from 200 m to 800 m above the sea level was segmented into 100 m unit. The result of analysis has shown that the Tamias sibiricus is the dominant specie throughout in all segments. Species confirmed to be inhabiting in all segments of research areas were Mustela sibirica, Caproelus pygargus and squirrel. By analyzing the confirmed Field Sign basing from the observation point, it has shown close relations between types of species and population following the increase in altitude (y=-0.0234 + 25.552, $R^2$=0.9296, $F_{0.05}$(1,4)=7.71, p<0.05). However, the result of analysis targeting nine species inhabiting in at least five out of six 100 m segmented units has shown that only two species, Apodemus sgrarius (y=-0.034X+25.2, $R^2$=0.905, $F_{0.05}$(1, 4)=38.169, p<.0.01) and Sciurus vulgaris (y=-0.0154X+ 12.819, $R^2$=0.781, $F_{0.05}$(1, 4)=14.270, p<0.05) were affected by the altitude. Therefore, it is judged that the distribution of species does not follow the altitude variation but follows the food conditions and the structure of habitat. The result of analysis of Box and Whisker Diagram had shown lowest quartile deviation($Q_U-Q_L$) in Nature Restoration Area that is located in $200{\sim}300m$ above the sea level, where hikers are prohibited from entering. In $500{\sim}600m$ above the sea level segment that has similar food environment and trail, it has shown the widest distribution. Further research is required on this segment for the excretion drops of Prionailurus bengalensis, a Grade II class of endangered species, were found on the trails.

• Korean Journal of Environmental Agriculture
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• v.21 no.1
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• pp.50-56
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• 2002

This experiment was carried out to obtain some information about overwintering, physiological and ecological characteristics of apple snails. Another purpose of this experiment was to characterize an appetite for rice plants by apple snails and to elucidate their choice of fresh green ones (vegetables, some other crops, weeds in rice fields). The freshwater snails were found with higher population at sites abundant organic compounds such as plant debris and at regions with high temperature. They also prefer calcium-rich water. This is a naturally occurring process. Apple snails were exceptionally veil-adapted to the south regions of Korea, especially Janghang, Jangseong and Haenam, even if the temperature of winter season is cold below 0$^{\circ}C$. Apple snails were not very selective in their food choice and eat almost everything available in their environment. A snail have something called a radula in its mouth for grinding up its food. A apple snail also chews on fruits and young succulent plant barks. In case of reproduction. apple snails deposit about 157$\sim$784 (average of 321 eggs) milky white to pale orange colored eggs above the waterline. In approximately every 22.4 seconds a new egg appears. The total time needed to deposit a egg mass varies from 58 minutes$\sim$4 hours 13 minutes. Apple snails reproduct actively from May to June and from September to October. An appetite of apple snails for rice plants was the different depending on their size and glowing stage for rice plants. Apple snails had a great appetite of rice plants as well as dropwort, tomato, cabbage, radish, aquatic plants etc. They preferred to eat young rice plants and drastically quit eating rice plants of over 40 cm in height. Thus considering the food preference of apple snail for various plants including rice, they were thought to be a potentially strong predator in fields, especially, at regions with warmer winter.