• Journal of the Korean Society of Hazard Mitigation
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• v.8 no.4
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• pp.111-118
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• 2008

Riparian buffer zone prevents sediment entry into drainage channels or as a protection from runoff and wind erosion. However, Studies about its removing effect according to Riparian buffer zone are shorted now. In this study, using the SWAT model, Byongseong watershed is built on the Arcview GIS. Using the function of the filter strip in SWAT model, it is also examined about the variation of sediment yield. As a simulation result, the case of constructing riparian buffer zones at subbasins near the outlet shows generally high efficiency on removing sediment yield. In addition, according to the scenario analysis of changing riparian buffer zone width, it is thought that 5-10m riparian buffer zone width is the highest efficiency on removing sediment yields generated from Byeongseong watershed.

• Journal of the Korean Institute of Landscape Architecture
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• v.28 no.5
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• pp.39-47
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• 2000

This study is to investigate the conditions closely related to the establishment of vegetation in the riparian zone: the soil condition, an important factor along with climate and light. Especially, the soil structure of the microtopographical formations in the specific area known as the riparian microtopographical zone investigated. In addition, the effect of the riparian microtopographical features on the ground water level, soil moisture content, and vegetation was studied. The results of this study are as follows; 1) At all sample sites, below the sand layer, a gravel layer is always present. This is the result of past floods. 2) Although Salix koreensis experiences frequent disturbances such as increase in river level and floods, this vegetation establishes itself in the most secure are in the microtopographical zone. 3) The growth of Phragmites japonica is closely related to the underground water level. 4) It is clear that Miscanthus sacchariflorus grows concentrated in dry areas. 5) The soil accumulation conditions differ according to the soil moisture content of each microtopgraphical feature. Accordingly, the moisture content of the soil is clearly different within the microtopographical zone. The continuous and long-term investigation and research on the relation of riparian reproduction and the relevance with location surrounding factors are necessary in the future.

• Journal of the Korean Institute of Landscape Architecture
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• v.27 no.4
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• pp.39-49
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• 1999

Urban streams have, recently, been straightened and widened to alleviate flooding problem. As a result, the stream have been modified inadvertently for ecological functions and microtopography. In this study, we investigated riparian vegetation and microtopography of the tributaries of Han River before and after the monsoon rain in summer. The purpose of this study was to relate the stream microtopography to the distribution of riparian vegetation. The stream microtopography was investigated for its scale and pattern. Vegetation was investigated from 131 plots by Braun-Blanquet method. The distribution of riparian vegetation was significantly correlated with the stream microtopography. Various herbaceous species occurred at stream bank slop, high terrace and channel side. However, at channel side and concave part of terrace where soils were in high moisture level, only a few wetland species were dominated. The complexity of the microtopography in the stream corridors led to heterogeneous riparian vegetation. The vegetation showed more stability against flooding at the stream corridors with natural and complex microtopography than at the urban-type stream corridors with simple topographical features. The results showed that the development of riparian vegetation was influenced by the changes in microtopography, which was primarily determined by the shape and characteristics of channel. It seemed that a close-to-nature river system would be restored more readily with an understanding of microtopographical features affecting the distribution of riparian vegetation.

• Journal of Korean Society on Water Environment
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• v.26 no.6
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• pp.910-918
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• 2010

In recent years, riparian buffer system has been known as one of the effective best management practices. However, establishment of riparian buffer system in aspect of plant species and its position in the riparian buffer zone has not been investigated due to lack of efficient evaluation method for the analysis of water quality improvement with established riparian buffer system. To solve this problem, the SWAT-REMM prototype was developed by the researchers in Canada. But, SWAT-REMM model can not consider the $NO_3-N$ load into riparian buffer system through subsurface flow. Thus to solved this problem, Fortran code of SWAT-REMM model was modified. This modified SWAT-REMM system was applied to the Bonggok watershed. Three riparian buffer scenarios, 15 m, 10 m, 5 m width for tree and grass, were made to evaluate the effects of riparian buffer system on water quality improvement. Reduction efficiency of T-N by riparian buffer system of 15 m wide was the greatest (6 ~ 37%, depending on subwatershed characteristics) among 3 scenarios. It indicates that the reduction efficiency of T-N load has increasing-tendency, as buffer width increasing. The results obtained from the analysis showed that wide buffer zones are found to be more effective in reducing non-point pollutant than narrow buffer zones in the riparian buffer zone system. Hence, the SWAT-REMM model could be efficiently used for evaluation and design the most effective riparian buffer systems to reduce pollutant loads to the watershed although many limitations still exist in SWAT-REMM model.

• Journal of Ecology and Environment
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• v.36 no.4
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• pp.235-243
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• 2013

In Korea, where the plain land is greatly deficient as a mountainous nation, most of riparian zones were transformed into agricultural fields and urban areas. Excessive use of the land, which is close to river, makes the rivers enduring severe pollution stresses. Disappearance of riparian buffer, which plays a function of filter in the riverside, appears as a main factor aggravating water pollution of rivers. In this respect, it is imperative to restore the lost riparian vegetation. This study found out restoration models of riparian vegetation from the Bongseonsa stream, which has remnant riparian vegetation patches as a conservation reserve. Feasible reference information applicable for restoration of riparian vegetation was shown in the species level in the order of herb, shrub, and tree and sub-tree zones as far away from the waterway. Those information could contribute to restoring integrate and healthy rivers and streams beyond simple landscaping differently from the other restoration projects when they will be applied to the restoration project to be carried out in the future. In addition, the spatial range of river and stream, background that riparian zone disappeared in Korea, and application plan of the obtained reference information were discussed.

• Journal of Environmental Science International
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• v.17 no.2
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• pp.149-162
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• 2008

Aquatic and riparian vegetation of river ecosystems are very important both in ecological and management perspectives. Vegetation surveys were conducted to understand the characteristics of riparian vegetation in the mid and lower reaches of the Nakdong River, Korea. A total of 68 families and 260 species were identified at eleven survey sites. The numbers of taxa were similar to those reported in a previous survey in 1996,but the percentage of naturalized plants increased more than two times compared to that in the previous survey. Survey sites near Yangsan Bridge and Nambu Park in Yangsan showed the highest percentage of naturalized plant species. Urbanization indices of the survey sites were high at 18.8% on average. Therophytes were the most dominant plant life form at the survey sites with 39.2% of total plants identified, followed by phanerophytes (19.2%), hemicryptophytes (18.9%), aquatic plants (13.9%), cryptophytes (5.8%), and chamaephytes (3.1%). The relative composition of hemicryptophytes decreased whereas those of therophytes and chamaephytes increased compared to those in the survey in 1996. This may be due to increase in dryness of riparian soils or degradation of riparian areas. Plant compositions at sites near Jeokpo Bridge and Hwoicheon suggest that the composition and distribution of riparian vegetation are affected by land use pattern surrounding riparian areas or human accessibility to the areas.

• Proceedings of the Korea Water Resources Association Conference
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• 2005.05b
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• pp.1274-1279
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• 2005

The complex vegetation and plant species distributions within riparian corridors influence plant species diversity patterns at both local and regional scales and further reflect both natural and anthropogenic disturbances. Because of these characteristics, riparian zones are often the ecosystem level component that are most sensitive to changes of the surrounding environment; they provide early indications of environmental change and can be viewed as the important source in the watershed. The objectives of this study were two concepts: first, document the composition and dominance of plant communities of riparian areas in the stream, second, compare species composition and temporal diversity between stations in riparian areas of the Ian Stream. The flora was composed to total 158 kinds of the vascular plants as 49 family, 54 genera, 145 species, 12 varieties, 1 forma When the naturalized plant were applied to the recent classification system 280 kinds, the naturalization rate was $10.8\% higher than that of mean value($10.3\%$) of the Korean mountain district. Furthermore, urbanization index (UI) was $6.1\%$. The dominant vegetation communities were distributed in the habitats of three compartments from upstream to downstream. The vegetations were included Phragmites japonica, Salix gracilistyla, S. hulteni and Robinia pseudo-acacia in the riparian area, and Persicaria sieboldii, Stellaria alsine var. undulata, Draba nemorosa var. hebecarpa, Capsella bursa-pastoris, Lepidium apetalum, Bidens frondosa, Trigonotis peduncularis and Hemistepta lyrata in the sandbank or the riparian area, and Equisetum arvense, Humulus japonicus, Persicaria perfoliata, Trifolium repens, Artemisia princeps var. orientalis, Lactuca indica var. laciniata, Avena fatua, Agropyron yesoense, Oenothera odorata, Viola mandshurica, Rumex crispus in banksides, respectively.

• Journal of Forest and Environmental Science
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• v.34 no.1
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• pp.31-45
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• 2018

At present the biodiversity of the riparian forest is under threat due to various anthropogenic pressures. Hence study was conducted along the three unprotected zones of riparian forest in Dikhu river, Nagaland, north-east India in order to compared the diversity, distribution and population structure of riparian trees. In each zone $100{\times}100m^2$ plot were marked and subdivided into 20 plots of $10{\times}10m^2$. 10 plots on each side of the river were taken randomly covering 0.02 ha. Only tree with dbh ${\geq}10cm$ and dbh above 1.5 m above ground level were recorded as individual species. A total of 29 tree species belonging to 18 families were recorded from the three zones of the river. Tree species richness was highest at the middle zone (19) followed by upper (14) and lower zone (7). The most abundant species and family recorded at upper, middle and lower zones were Melia azaderach of Euphorbiaceae ($380\;stems\;ha^{-1}$), Terminalia chebula of Euphorbiaceae ($432.5\;stems\;ha^{-1}$) and Duabanga grandiflora of Lythraceae ($365\;stems\;ha^{-1}$) respectively. The ranges of diversity indices observed in the three zones were: Shannon-Wiener index (1.25-0.73), Simpson diversity index (0.42-0.93), Evenness index (0.47-0.37) and Index of co-dominance (0.75-0.94). Rest of other indices were also estimated and compared. Distribution of trees shows the contagious pattern common in the upper and middle zones and regular in the lower zone. The girth size class analysis demonstrated that the riparian forest is in less mature succession stage. This study emphasize the need for management and conservation of riparian forest by developing policy to declare the riparian zone as protected area to prevent further degradation and loss of biodiversity from these unregulated zones along the river.

• Journal of Environmental Impact Assessment
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• v.21 no.6
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• pp.903-916
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• 2012

We need to use aesthetic landscape assessment(ALA) as the means of riparian buffer zone(RBZ) management. This study verified the political validity of designation policy of RBZ and land purchase policy. The purpose of this study was to propose RBZ landscape management strategies through ALA of RBZ in Gyeongan Stream for the better attractive and healthy riparian landscapes. The natural type landscape units(LUs) covered 40.9% of the entire area and the cultivated land type LUs covered 20.58%. Landscape assessment consisted of landscape quality and landscape integration assessment. The criteria for assessing landscape quality(LQ) were naturalness, interest, uniqueness, and landscape function. LQ was ranked into five grades using a matrix. The landscape integration assessment consisted of an inner integration assessment in each LU and outer integration assessment among LUs. To review the propriety of designating the riparian area and the riparian ecological belt, differences in ecological appraisal and aesthetic valuation were reviewed through a t-test, Oneway ANOVA, and logistic analysis. The results of ALA, 29.15% of the entire area scored at grade 1 in LQ, while 31.95% scored at grade 5, indicating that grade 5 areas occupied a high share. Surveyed areas were divided into designated RBZ and undesignated RBZ. Results indicated that designated RBZ scored grade 1 in LQ took up 33.2% of the total, significantly higher than the 23.3% taken up by undesignated RBZ. When examined according to buffer distance, grade 1 areas within 50m took up 50.2% of the total area, lower than the 32.7% at buffer distances of 500m-1km. Results indicated a 1% statistically significant difference. Accordingly, analysis was undertaken for the expansion of designation of the riparian area and the selection of appropriate land for formation of a riparian ecological belt, and was designated at priority 1 and 2 for land purchase. This study can also contribute to the formation of a riverine eco-belt through discovery of design factors for upgrading the ecology, aesthetics, and landscape of the riparian area and application in determining land purchase priorities.

• Journal of Environmental Science International
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• v.26 no.12
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• pp.1341-1353
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• 2017

This study aimed to identify the aquatic and riparian factors associated with the presence/absence of the Eurasian otter in the Nakdong river basin, where the species is relatively more abundant than other otter species. Environmental factors and presence records were collected. Geographical Information System technology and chi-square test were used to compare environmental gradients in aquatic and riparian factors between presence and absence sites. Aquatic habitat attributes were evaluated with natural riverside sandbars and channel crossing artificial structures, the ratio of channel width to alluvial plain width, riverbed substrate, and flow diversity. Riverbank characteristics, bank materials, man-made embankment types, and land use/land cover of inland and riverside areas were selected as riparian habitat attributes. Compared to the aquatic attributes, riparian attributes were highly significant when assessing otter presence and absence sites, suggesting that conservation of suitable riparian areas to provide maternity and resting areas for otter species is essential in the Nakdong river basin. None of the aquatic attributes examined were statistically significant when evaluating otter presence or absence. These results indicate that the presence of suitable riparian area for resting and reproduction habitats is more critical to the presence of Eurasian otter than food availability in aquatic areas. To inform implementation of effective conservation actions, broad-scale factors, such as watershed attributes, would be needed to further assess habitat conditions of the Eurasian otter.