• Title/Summary/Keyword: Natural stream

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Ichthyofauna and Habitat Type of the Fish in Tamjin River System, Korea (탐진강 수계의 어류상과 어류의 서식형)

  • Nam, Dong-Woo;Cha, Seong-Sig;Choi, Chung-Gil;Lee, Jong-Bin;Lee, Hak-Young
    • Journal of Environmental Science International
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    • v.18 no.9
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    • pp.1001-1010
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    • 2009
  • To investigate the ichthyofauna and habitat type of the fish in Tamjin River system, Korea, fishes were collected with cast net ($5{\times}5\;mm$, $8{\times}8\;mm$) and dip net ($4{\times}4\;mm$) at eight stations seasonally during five years from 2000 to 2004. 56 species belonging to 18 families were collected and 15 Korean endemic species( 26.8%) were investigated. While Coreoperca kawamebari was occurred at every station, the number of individuals and composition were decreased. Anguilla marmorata was not collected and the exotic species didn't appeared. Dominant species were Zacco platypus(34.2%), Squalidus gracilis majimae (9.4%), Microphysogobio yaluensis(8.1%), Zacco temmincki(6.8%) and Acheilognathus lanceolatus(5.1%). The surveyed stations were clustered into 3 groups: up stream, main stream and estuary. With the cluster analysis using the relative abundance of major fishes at each habitat, fishes were separated into 5 habitat types: U (upstream type), UM (up and main stream type), M (main stream), ME (main stream and estuarine type), and E (estuarine type).

The Analysis of Vegetation Characteristics According to Revetment Structure at Rural Small Streams (농촌지역 소하천의 제방형태에 따른 식생특성 분석연구)

  • Kim, Mi-Heui;Kang, Banghun;Kong, Min-Jae;Jeong, Myeong-Cheol;Son, Jin-Kwan
    • Journal of Wetlands Research
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    • v.17 no.4
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    • pp.359-369
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    • 2015
  • Stream ecosystems are highly valued natural resources, however, stream environments are currently under threat in several respects. We evaluated vegetation and ecological characteristics according to different revetment types. The distribution of vegetation differed with revetment type, with a 42~45 taxa found in natural revetments, and 23~38 taxa in vertical revetments. Thus, natural revetments host more diverse vegetation than vertical revetments. We also found more plants belonging to the families Labiatae and Cyperaceae growing in natural revetments than in vertical revetments. We proposed that habitat space be apportioned to introduce annual plants as part of stream restoration projects. And, we identified 7 families and 18 taxa of naturalized plants, majority taxa were either biennial or perennial. Moreover, naturalized ratio was higher in vertical(14.3%) than natural(12.1%), we proposed a plan to promote and improve natural streams and revetments. Furthermore, we applied a waterfront evaluation method developed by the Natural Resources Conservation Service of the USDA-NRCS, which confirmed that stream health can be improved in most regions by controlling naturalized plants and ensuring shrub and tree growth. We adopted a new method to remove naturalized plants and establish natural revetments to ensure shrub and tree growth to aid in small-stream restoration and improvement. In future studies, we hope to develop methods for small-stream restoration projects in rural areas.

The Riparian Vegetation of Close-to-Nature River${\cdot}$Streams in Korea

  • Kim, Chul;Yang, Hyo-Sik
    • Korean Journal of Plant Resources
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    • v.20 no.3
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    • pp.234-241
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    • 2007
  • The present study was undertaken to classify and describe the riparian vegetation of the 6 river${\cdot}$stream of Korea Peninsula. As a result the vegetation was divided into nineteen communities. The vegetation units obtained in the present study were as follow: A: Salix koreensis community, B: Salix gracilistyla community, C: Robinia pseudo-acacia community, D: Amorpha fluticosa community, E: Brousonnetia papyrifera community, F: Phyllostachys bambusoides community, G: Rubus corchorifolius community, H: Phramities japonica community, I: Phramites communis community, J: Miscanthus sacchariflorus community, K: Miscanthus sinesis var. purpurascens community, L: Artemisia princeps var. orientalis community, M: Humulus japonicus community, N: Zoysia japonica community, O: Inperata cylindrica var. koenigii community, P: Agropyron tsukushiense var. transiens community, Q: Juncos effusus var. decipiens community, R: Rumex crispus community, S: Persicaria hydropiper community. The vegetation characteristics of riversides was recovered in the surveyed results according to river${\cdot}$stream basin, in other words, 10 communities in the upper river${\cdot}$stream riparian, 15 communities in the middle river${\cdot}$stream riparian, 10 communities in the down river${\cdot}$stream riparian. The Phragmites japonica community in the upper and Phragmites communis community in the down was analyzed by common community of the 6 river${\cdot}$stream riparian, respectively, but none in the middle. The standing profile of vegetation across 6 river${\cdot}$stream was seen stepwise Phragmites japonica community, Salix gracilistyla community, Miscanthus sinensis var. purpurascens community, shrub community by natural waterway in the upper, Salix gracilistyla community, Phragmites communis community, Rumex crispus community, Miscanthus sacchariflorus community, Humulus japonicus community in the middle, Phragmites communis community in the down. The differences of distributional featurs of vegetation emerged from the riparian of the 6 river${\cdot}$stream, but don't from the 6 river${\cdot}$stream.

Review on the Improvement Works of Ecological Stream in Rural Areal - A Focused on Sijeon-ri Dogo-myeon Asan City - (농촌지역 하천정비공사 실태와 제언 -아산시 도고면 시전리를 대상으로-)

  • Nam, Yun-Cheol
    • Journal of the Korean Institute of Rural Architecture
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    • v.17 no.2
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    • pp.51-58
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    • 2015
  • 10 years ago, in Sijeon-ri, Dogo-myeon, Asan-si, the existing stream was repaired to develope Mt. Dogo trail and irrigation systems through road expansion pavement construction and small stream repair construction. The trees such as persimmon and willow are eliminated that rowed on both sides of the stream and dredging work to dig the rock and sand have been performed. As a result, wide asphalt road was built, also flood damage worries were reduced. 10 years passed and now, how did local residents think about the stream repaired before and after? Village residents, public officials, and the stream construction engineer were interviewed. Villagers indicated a problems that brook became a place where water peppers were taking over and water was stagnating due to the slow velocity so nothing could live and natural landscape like a wash place and the cascade disappeared, because rock and sand were taken out brought soil into the brook. Public officials and engineers were aware of the problems at the time of the stream. Now that construction is completed after 10 years, Both realistically and budgetary to restoration would be difficult. However, it is necessary to seek for waterfront space which can be restored or replaced by a part of the stream like similarly before. In addition, it is necessary to restore to the progression of a natural stream which connect with stairs(or slope) - small waterfalls - pools - wash place. In this paper, we hope to take a lesson from the Sijeon-ri model and make rural stream construction be prepared with consideration about not only distinct characteristics of specific area but also the opinion of local resident.

Residents'prefrences for Rural stream bank materials (농촌 마을내부 소하천의 하안재료에 대한 주민 선호도에 관한 연구)

  • 이춘석;류남형
    • Journal of Korean Society of Rural Planning
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    • v.3 no.2
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    • pp.81-89
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    • 1997
  • Still today, many streams are channelized and embanked in Korea. On the other hand, some urban streams are being restored to their natural shapes by landscape planners. It would be better to improve rural streams in a way that would not require restoration in later days. Then, one important question is what kind of embankments the residents prefer for what reasons. Five simulated photos showing from very natural to artificial embankments were used in surveying 90 residents of three villages. Major findings are ; 1. Residents regard safety(from flooding) is the most critical factor to be considered in selection of stream bank materials. 2. They think ideal materials are natural stones or concrete blocks as they look tidy. Concrete retaining walls or vegetated natural slopes are not regarded good. 3. The most preferred material is concrete retaining wall, and the least preferred is vegetated natural slope. They prefer concrete retaining wall which they do not think an ideal material, because it will make a safe bank. 4. Natural stone bank is most preferred for its apperance, and vegetated natural slpoe is most disliked as it may collapse and as it does not look clean.

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Seasonal Phosphorus Dynamics in a Forest Stream Water Following Different Harvests

  • Park, Byung Bae
    • Journal of Korean Society of Forest Science
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    • v.97 no.2
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    • pp.181-186
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    • 2008
  • Even small changes in phosphorus concentrations in stream water could cause eutrophication because of very low level of phosphorus concentrations in natural waters. I investigated the impact of strip cut and clear cut on phosphorus concentrations in stream water at the Hubbard Brook Experimental Forest and investigated stream water phosphorus concentrations as a function of flow rate and season (as well as cutting history). Mean phosphate concentrations in the control (undisturbed forest) increased $1.9{\mu}g\;L^{-1}\;to\;2.6{\mu}g\;L^{-1}$, while strip cut treatment increased phosphate concentrations in stream water $2.2{\mu}g\;L^{-1}\;to\;3.7{\mu}g\;L^{-1}$ during the same period. There was no significant effect of clear cut treatment on phosphate concentrations in stream water. No relationships were found between discharge rate and phosphate concentrations, but the magnitude of fluctuation were increased during two decades in undisturbed forest: $1-5{\mu}g\;L^{-1}$ from 1963 to 1975 and $1-12{\mu}g\;L^{-1}$ from 1983 to 1995. Based on this study, forest harvests with buffer zone will not make a problem by imported phosphate to cause eutrophication in natural water.

Modeling Transverse Velocity Profile in Natural Streams (자연하천의 유속 횡분포 모델링)

  • Seo, Il-Won;Baek, Gyeong-O
    • Journal of Korea Water Resources Association
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    • v.32 no.5
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    • pp.593-601
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    • 1999
  • The knowledge about structure of the velocity in the stream IS essential in the investigation of stream meandering, erosion and sediment transport, and dispersion of pollutants in the stream. In this study, theoretical velocity profile model in which transverse profile of the longitudinal velocity in the stream can be predicted using stream hydraulic data was developed. The proposed model was tested with the measured velocity data of the Nakdong river. The result shows that the numerical model simulates properly the general shalxc of the measured velocity profiles. The simulated profiles agree well with measurements, especially in the aspects of skewness and flatness.atness.

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Analysis of Natural Organic Matter (NOM) Characteristics in the Geum River (금강 수계 자연유기물 특성 분석)

  • Yu, Soon-Ju;Kim, Chang-Soo;Ha, Sung-Ryong;Hwang, Jong-Yeon;Chae, Min-Hee
    • Journal of Korean Society on Water Environment
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    • v.21 no.2
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    • pp.125-131
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    • 2005
  • Natural organic matter(NOM) is defined as the complex matrix of organic material and abundant in natural waters. It affects the performance of unit operations for water purification. Several kinds of analytical indicators such as DOC, specific ultraviolet absorbance(SUVA), apparent molecular weight (AMW), fractionation and high performance size exclusive chromatography(HPSEC) have been used to understand characteristics and variations of NOM. This study aims to evaluate the characteristics of NOM in the Geum River system comprising with stream flows and reservoirs. It was identified that SUVA denoting the portion of humic substance in water ranged within 1.60~3.36. Using resin adsorbents, dissolved organic carbon(DOC) was fractionated into three classes: hydrophobic bases(HOB), hydrophobic acids(HOA) and hydrophilic substances(HI). HI dominates in all samples, collectively accounting for more than 62% of the DOC. HOA was the second dominated fraction and it varied considerably but accounted for about 30% of the DOC. The distribution of high molecular weight(HMW) measured by HPSEC being used to determine the molecular weight distribution of aquatic humic substances was 40.1% and 38.7% in reservoir and stream flow, respectively. The distribution of low molecular weight(LMW) in stream flow was 13.2% higher than that in reservoir. And apparent molecular weight less than 1KDa, which include the molecular weight of hydrophilic organic matter, occupied with 69.2% and 68.2% in stream flow and reservoir, respectively. While the molecular weight of 1 to 100 KDa including humic substances ranged with 18.6% and 21.6% in stream flow and reservoir, respectively. Seasonal variation of refractory dissolved organic carbon was similar to that of SUVA.

Study on Feeding Habits of Micropterus salmoides in Habitat Types from Korea (서식처 유형에 따른 배스 Micropterus salmoides 식성의 차이)

  • Park, Jong Sung;Kim, Su Hwan;Kim, Hyun Tae;Kim, Jae Goo;Park, Jong Young;Kim, Hyeong Su
    • Korean Journal of Ichthyology
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    • v.31 no.1
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    • pp.39-53
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    • 2019
  • In order to compared the feeding habits of Micropterus salmoides according to the habitat types, the stomach content of a total of 306 M. salmoides were investigated from April to September 2016 in the stream and reservoir. As a result, the highest IRI (Index of relative importance) value in M. salmoides inhibiting the stream and reservoir were identified as fishes. However, the IRI value of crustaceans and insects as well as fishes in M. salmoides inhibiting the reservoir were high, showing a difference in IRI value of M. salmoides inhibiting the stream.

The Evaluation Perspective of Stream Weight in AHP (계층분석법을 이용한 하천의 중요도 평가기법)

  • Park, Tae-Sun
    • Journal of Korea Water Resources Association
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    • v.35 no.6
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    • pp.685-692
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    • 2002
  • It is very useful to estimate easily the various characteristics of streams and to manage objectively streams, as the order or grade among streams is determined by the natural characteristics and the degree of human utilization. With obtainable various statistics data and expert examination, we proposed the measurable evaluation index of "stream weight" considering the natural characteristics of streams, the utilization degree of streams and the social conditions of the regions crossed streams. The each stream weight is calculated as follows. Firstly, select the various factors which influence to streams in AHP. Secondly, determine the each weight of factors by the result of expert examination. Finally, sum up after multiplying the normalized factors by these two values. The stream weight can be used such divisions as the recognization of relative weight between streams, the determination of the stream management direction in the near future, the enhancement of the efficiency of stream management through the adjustment of the present stream grade and the determination of the management method concerned the stream weight as well.t as well.