• Korean Journal of Ecology and Environment
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• v.56 no.4
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• pp.384-392
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• 2023

Stomatal pore is an important physiological trait that is closely linked to photosynthesis and transpiration as carbon dioxide and water vapor move through it between the atmosphere and plants. The present study investigated stomatal traits, such as stomatal density, index and size, of herbaceous native and alien plant species living in a riparian park on the Nakdong River to understand how those traits vary and to know if successful settlement of alien plants is attributed to those traits. There was no difference in stomatal density, index and size between native and alien plants with kidney-shaped stomata, suggesting that an empty ecological niche is not an essential prerequisite for the successful settlement of alien plants. Stomatal density showed a negative correlation with leaf thickness and leaf dry weight content (LMDC), but there was no correlation with Specific leaf area (SLA). All plants with kidney-shaped stomata had amphistomatous leaves, and the density and size of dumbell-shaped stomata were lower than those of kidney-shaped stomata.

• Korean Journal of Ecology and Environment
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• v.37 no.2 s.107
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• pp.227-235
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• 2004

Fish fauna and community structure were surveyed in the Nakdong River, Gumi City, Kyeongpook province from April 2001 to July 2002. During the surveyed Period, 39 species, 32 genera belonging to 10 families were collected. Cyprinid fish occupied 64.1% (25 species) and cobitid fish had 7.7% (3 species). Fourteen species(35.9%) of observed species were known as endemic species. The exotic fish was Micropterus salmoides (2.5%) . The dominant species were Zacco platypus (relative abundance: 36.7%) and Opsariichthys uncirorstris amurensis (22.7%). Carassius aurafus and Microphysogobio rapidus were numerous (4.0${\sim}$4.3%). The rare species comprising less than 0.15% were Acheilognathus koreensis, Aphyocypris chinensis, Iksookimia longicorpus, Coreoleuciscus splendidus, Rhinogobius giurinus, Sarcocheilichthys variagatus wakiyae, Silurus asotus astus, and Channa argus. It was found that the population density of carnivorous Opsariichthys uncirostris amurensis increased drastically in the mid-reach of the Nakdong river since it had been introduced from the other native rivers in the middle 1990s. Gobiobotia nakdongensis inhabit riffle (water velocity : 0.43${\sim}$0.67 m $s^{-1}$) of which the river bed is mainly sand. This species is considered to be in need of conservation. As the result of analyzing fish community in the surveyed area, the species diversity, evenness and dominant indices were 1.008, 0.663 and 0.196 respectively. The findings showed that the tributary, which the waterside plants were abundant and had various habitats, had a higher species diversity (1.112) than the main river (0.787). Sand mining had been disturbing the river ecosystem of the study stations 3, 11, 13 & 14, and these stations showed a quite low species diversity (0.421 ${\sim}$0.574).

• Journal of agriculture & life science
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• v.44 no.3
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• pp.15-21
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• 2010

We estimated the biomass productivity and the storage potential of nitrogen, the major contributor of non-point source pollution, with four three-year-old four poplar clones in a riparian woody buffer established in the Anseong River in Anseong, Korea. Stem of Populus alba ${\times}$ P. glandulosa clone 72-31 and Populus deltoides ${\times}$ P. nigra clone Dorskamp showed the highest percentage of aboveground biomass components, followed by branch and leaf. Nitrogen content in aboveground biomass components of two poplar clones was the highest in leaf and the lowest in stem. Nitrogen content in leaf and branch of clone 72-31 was higher than that of clone Dorskamp, while it in stem was lower. Populus deltoides clone Ay48 showed the highest above-ground biomass productivity, which was estimated as $37.5ton\;ha^{-1}$ at age 3. However, clone 72-31 was the lowest in above-ground biomass productivity. Nitrogen storage potential in aboveground biomass of 3-year-old poplar clones was high in order of aboveground biomass. Clone Ay48 showed the highest nitrogen storage potential in aboveground biomass, which was estimated as $218.3kg\;ha^{-1}$ at age 3.

• Journal of the Korean Institute of Landscape Architecture
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• v.40 no.2
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• pp.1-14
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• 2012

The purpose of this study is to derive a desirable riverfront construction plan to me for the activities of citizens through the evaluation and analysis of the urban riverfront space from the perspective of universal design. Therefore, previous studies were examined in order to induce evaluation tools that bhve been grafted from the universal design concept; in addition, a field survey was conducted in Shincheon, Daegu, which was selected as the study target, in order to induce problems and improvement directions from the perspective of universal design. The major results can be summarized as follows. (1) In the 'fairness' aspect, all the items such as installation of integrated functional signage, showing pictures, symbols, foreign language signs, and restroom entrances signage were determined to be 'All Unsuitable' for all sections; and therefore, it is necessary to improve the fairness of usage for everybody. (2) In the 'Functionality(Usability)' aspect, all items such as installation of bicycle paths beside access roads, installation of integrated functional signs, and night light signs were determined to be 'All Unsuitable' for all sections; therefore, it is necessary to improve the functionalities of these facilities. (3) In the 'Convenience' aspect, all items such as the installation of bicycle parking areas, continuous rest facilities, and back and ann support(handles) at resting facilities were determined to be 'All Unsuitable' for many sections; therefore, it is necessary to improve these facilities for the convenience of usage. (4) In the 'Information(Recognizability)' aspect, all items such as showing pictures, symbols, foreign languages and installation of night light signs, and restroom entrances signage were determined to be 'All Unsuitable' for all sections; therefore, it is necessary to improve the recognizability to minimize misunderstandings and confusion. (5) In the 'Safety' aspect, all items such as the installation of safe pedestrian paths in parking areas, using anti-slip and shock absorption materials on restroom floors, and the continuous installation of pedestrian paths that are separate from bicycle paths were determined to be 'All Unsuitable' for all sections; therefore, it is necessary to improve the safety to prevent accidents. (6) In the 'Amenity' aspect, access roads, parking areas, hygiene facilities, convenience facilities, and waterside facilities for many sections were determined to be 'All Unsuitable'; therefore, it is necessary to conduct more concentrated hygiene management. (7) In the 'Accessibility(Mobility)' aspect, all items such as the installation of safe pedestrian paths in parking areas, and continuous pedestrian paths that are separate from bicycle paths were determined to be 'All Unsuitable' for all sections; therefore, it is necessary to improve the accessibility to provide safety and convenience. (8) In the 'Durability' aspect, access roads, parking areas, rest facilities, convenience facilities, fitness facilities, and waterside facilities were determined to be 'All Unsuitable' for many sections, therefore, it is necessary to improve sunken or damaged areas by inspecting facilities by section.

• Korean Journal of Environmental Biology
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• v.30 no.2
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• pp.107-120
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• 2012

This study was carried out to illiminate the diversity of vascular plants by making list of rheophyte and hydorphyte plants at Yugu stream. This study was conducted from Aug., 2009 to Sept. 2010 at 7 points. Based on the voucher specimens, vascular plants from investigated areas were 88 families 229 genera 290 species 3 subspecies 30 varieties 5 forms, totally 328 taxa. Korean endemic plants were 3 species such as Forsythia koreana (Rehder) Nakai (planted) and Paulownia coreana Uyeki (planted), and Weigela subsessilis (Nakai) L.H. Bailey. The rare and endangered plants were designated by Korea Forest Service were 4 taxa, such as Penthorum chinense Pursh, Acorus calamus L., Lilium callosum Siebold & Zucc. and Iris ensata var. spontanea (Makino) Nakai. Floristic special plants were totally 26 taxa, which were grade V of 2 taxa, grade IV of 2 taxa and grade III of 9 taxa. Naturalized plants were 27 taxa, that was 8.3% of whole discovered vascular plants in this area. Even naturalized plants has not influence on the vegetation of Yugu stream. Since village was composed along the stream and the roads and banks were linked, naturalized plants were flowed continuously into this region. So, strategy of the conservation for this region should be designed. Based on flora, 3 types of group were discriminated such as main stream type (4 points), branch stream type (2 points) and reservior type (1 point). Each group has difference in composition of plants.

• Journal of Korean Society of Steel Construction
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• v.25 no.6
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• pp.613-622
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• 2013

Numerous water gates have been constructed and are under construction for the control of water level because, due to the topographical characteristics of mountainous area, many small size rivers are developed in Korean peninsula. Among the water gates, movable water gates are more efficient to control water level than the fixed water gates. By the field application of the movable water gates, many problems associated with the fixed water gates have been mitigated. The problems include the bottom water pollution, the change of habitats for the riparian organisms, etc. This is the reason to increase the field application of movable water gates. In the paper we present the result of analytical investigation pertaining to the structural behavior of multistage overturning movable water gate which is one of the movable water gates. In the analytical investigations, the finite element analysis on the constructed water gate has been conducted for illustration purposes and it was found that the multistage movable water gate is much better than the fixed and/or existing movable water gates in the point of structural and environmental performances.

• Korean Journal of Ecology and Environment
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• v.40 no.2
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• pp.264-272
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• 2007

Runoff of non-point pollutants has affected bad influence to water quality of river as reaching within short time. For this reason, reducing them prior to reaching aquatic systems or treating them after collection from discharge process of pollutants are desirable for efficient treatment of pollutants. This study was carried out to develop an ecotechnological method to prevent further aggravation of water quality by non-point source through vegetation filter strips. This study has placed a focus on improving infiltration capacity of soil for the optimum condition of vegetation filter strips. Therefore, we used titled soil filter strips instead of vegetation filter strips in this study. The three types of soil tilter strips were used in a bench scale experiment before applying to the field. The reduction efficiency of pollutants in soil filter strips (SS $84.5{\sim}92.5%$, BOD $67.9{\sim}80.6%$, T-N $43.4{\sim}76.6%$, T-P $40.6{\sim}87.4%$, Cu $28.3{\sim}48.1%$ Fe $92.1{\sim}97.7%$, Pb $81.4{\sim}97.3%$) was much higher than that of the controled group. And non-point pollutants reduction efficiency by soil filter strip's forms was estimated to be distinguishing in order of bio material, mixture of sand and gravel and lastly the whole gravel. In the event, the whole reduction efficiency of pollutants on the soil filter strips disclosed good results.

• Ecology and Resilient Infrastructure
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• v.7 no.3
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• pp.171-180
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• 2020

With the increase in industrialization and urbanization, scarcity of space for leisure life has become an important issue. Opportunities such as natural scenery and ecological experiences provided by waterfront spaces around streams are fundamental factors in the development of the community and creation of a hydrophilic park. In the past, on-site surveys have been conducted using human resources to quantify the number of river visitors, but the accuracy of the results was not sufficient owing to limitations in expenses, manpower, space, and time. In this study, to overcome this problem, we estimated the number of visitors using the location information related to hydrophilic parks. The study areas were Samrak Ecological Park and Daejeo Ecological Park located downstream of the Nakdong River. We compared and analyzed the pattern of the visitors by using the large communication data and the visiting pattern based on GPS location information. The GPS location information is based on Google Popular Times and Kakao visitor data. When the GPS location data were used, the pattern for weekday and weekend visitors was clearer than when the large communication data were used. Therefore, it is expected to be similar to the result of GPS location information if the number of visitors is extracted under the condition of precision of pCELL size and residence time of 30 minutes or more when using future communication big data. In addition, if revisions such as the Personal Information Protection Act are made to extract more accurate data, by estimating the number of visitors based on GPS data, more accurate indicators of the number of visitors can be derived.

• Korean Journal of Ecology and Environment
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• v.53 no.4
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• pp.445-452
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• 2020

In this study, we carried out a distribution and migration boundary lines of chum salmon (Oncorhynchus keta) in the Milyang River. We measured the total length of dead chum salmons. As a results, 40 chum salmons were found during the study period, 25 dead salmons and 15 alive individuals. The ratio of female was 64%. We verified the migration boundary lines of chum salmons based on a sighting survey until detecting a structure that chum salmons are not able to migrate upstream. We discovered that chum salmons were not able to migrate up to 13 km in a mainstream of the Milyang River and up to 12 km in the Danjang stream (a tributary of the Milayang River) from upstream of the Yerim Bridge. Therefore, our results indicate that Milyang River should improve a river connectivity by demolishing weirs that disturb chum salmon's migration or installing appropriate fishways. Also, effective legislations are needed to retain naturality in spawning ground and micro-habitats to increase the survival rate of parrs and smolts.

• Korean Journal of Environmental Biology
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• v.29 no.4
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• pp.296-304
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• 2011

This study was carried out to investigate the relation between water quality and structure of the aquatic ecosystem in the Lake Gachang from February to December in 2010. The annual mean COD (Chemical Oxygen Demand) in Lake Gachang was 3.5 mg $L^{-1}$, indicating, level II of environmental standards and the trophic state was mesotrophic. The seasonal succession of phytoplankton showed that Bacillariophyceae was mostly dominant species throughout the year except August. In case of zooplankton, rotifers dominate in the most seasons, but copepod (Nauplii) in August. The macrophyte plants showed diverse species composition consisted of 9 varieties, 77 species, 64 genera, 34 families and 24 orders. Surveyed species of macroinvertebrates were classified into 1 phyla, 2 classes, 4 orders, 7 families, 9 species. The macroinvertebrates showed FFG (Functional Feeding Groups) such as GC (Gathering-Collector) and SH (Shedder). A total of 42 species of fish was collected including $Zacco$ $koreanus$ and $Coreoperca$ $herzi$. In this study, we investigated environmental factors including pollutant source, load, water quality and distribution characteristics of biota such as phytoplankton, zooplankton, macrophyte plants, macroinvertebrates, fish.