• Korean Journal of Environment and Ecology
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• v.34 no.3
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• pp.249-258
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• 2020

This study aims to provide reference material for effective forest management techniques at the catchment scale, based on the field investigation of large woody debris (LWD) in 11 streams within a third-order forest catchment in Gangwon Province, Korea. To achieve this aim, we analyzed the morphological features of LWD pieces, and the storage and distribution status of LWD by stream order throughout the entire investigation. As a result, a total of 1,207 individual pieces of LWD were categorized into three types as follows: (ⅰ) 1,142 pieces (95%) as only trunk and 65 pieces (5%) as a trunk with root wad, (ⅱ) 1,015 pieces (84%) as non-thinned and 192 pieces (16%) as the thinned, and (ⅲ) 1,050 pieces (87%) as conifer and 157 pieces (13%) as broadleaf. Additionally, in-stream LWD loads (㎥/ha) decreased with increasing stream order, yielding 105.4, 71.3, and 35.6 for first-, second-, and third-order streams, respectively. On the other hand, the ratio of LWD jams to the total LWD volume increased with increasing stream order, yielding 11%, 43%, and 49% for first-, second-, and third-order streams, respectively. Finally, a comparison of the in-stream LWD load with previous studies in several countries around the world indicated that in-stream LWD load was positively correlated with forest stand age even though the climate, topography, forest soil type, forest composition, stand growth rate, disturbance regime, and forest management practices were different. These results could contribute to understanding the significance of LWD as a by-product of forest ecosystems and an indicator of riparian forest disturbance. Based on this, we conclude that advanced forest management techniques, including treatment of thinning slash and stand density control of riparian forest by site location (hillslope and riparian zone, or stream order), should be established in the future, taking the forest ecosystem and the aquatic environment from headwater streams to low land rivers into consideration.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.17 no.4
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• pp.203-224
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• 2012

Definition of estuary and its administrative boundaries is needed for the practical management of estuarine environment. However, the majority of Korean estuaries are lack of scientific data required for defining the administrative boundaries. For this reason, a systematic way to set the boundaries has not been developed so far. This study proposed adaptive and comprehensive criteria in defining the boundary of an estuary based on the available data which includes physiochemical, geographical and topographical characteristics and regional data such as land uses and socio-economic conditions. An estuary boundary is defined with a sequential manner. First of all, according to the estuarine circulation pattern, 463 estuaries in Korea were classified into open estuaries and closed estuaries. Then an individual belonging to each type of estuary is defined an water zone boundary considering the physiochemical, geographical and topographical characteristics and land uses. Finally, a land zone boundary is set along the catchment. According to the proposed criteria, we have delineated 274 estuarine management zones in Korea on a trial basis and found that it was possible to set a boundary reasonably considering the difference of level of available data and regional characteristics in each estuary.

• Journal of the Korean Geographical Society
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• v.32 no.4
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• pp.445-462
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• 1997

This study was conducted to analyze the spatial and temporal characteristics of stream water quality and to charify the management of watershed environment from the standpoint of hydrological geography. To achieve the purpose of the study, the Wangsook River was chosen. As the result of this study, the specific conclusions were drawn. 1. In general, WT(water temperature) of the downstream is higher than that of the upstream. The value of winter WT measured in densely populated area is higher than that measured under the natural conditions. The seasonal variation of WT at upstream sites is greater than that of downstream. 2. Rhe water quality of main channel is dependent on that of tributaries. Especially, the values of pH, EC, TDS in main channel depend upon those of tributaries. Among the tributaries of the Wangsook river, the Jingun-chon and Yongam-chon have mostly influence on the water quality of the main channel. 3. Generally, the values of COD measured in the Wangsook River are over the 5th Grade considering from a point of water quality standards of inland lake. However, BOD, phosphorus and nitrogen concentrations have to be measured to clear the water quality conditions of the river. 4. The regional people who live in the catchment of Wangsook river have different perception about the water pollution of the river. The regional people lacks in the understanding of the Wangsook river cause a bad influence upon the hydrological management of watershed environment.

• Journal of the Korean Institute of Landscape Architecture
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• v.43 no.4
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• pp.98-111
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• 2015

Urban environmental problems such as flooding, depletion of ground water, pollution of urban streams and the heat island effect caused by urban development and climate change can be mitigated by the improvement of the urban water cycle. For the effective planning of water cycle management it is necessary to establish aerial Hydrotope Maps, with which we can estimate the status and change of the water allowance for any site. The structure of the German water balance model BAGLUVA, which is based on soil and vegetation, was analyzed and the input data and boundary condition of the model was compared with Korean data and research results. The BAGLUVA Model consists of 5 Input categories (climate, land use, topography, soil hydrology and irrigation). The structure and interconnection of these categories are analyzed and new concepts and implementation methods of topographic factor, maximum evapotranspiration ratio, effective rooting depth and Bagrov n parameter was compared and analyzed. The relation of real evapotranspiration ($ET_a$)-maximum evapotranspiration ($ET_{max}$) - precipitation (P) was via Bagrov n factor represented. The aerial and land use oriented Hydrotope Map can help us to investigate the water balance of small catchment areas and to set goals for volume of rainwater management and LID facilities effectively in the city. Further, this map is a useful tool for implementing water resource management within landscape and urban planning.

• Proceedings of the Korea Water Resources Association Conference
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• 2015.05a
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• pp.227-227
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• 2015

The Wairarapa Valley occupies a predominantly rural area in the lower North Island of New Zealand. It supports a mix of intensive farming (dairy), dry stock farming (sheep and beef cattle) and horticulture (including wine grapes). The valley floor is traversed by the Ruamahanga River, the largest river in the Wellington region with a total catchment area of 3,430 km2. Environmental, cultural and recreational values associated with this Ruamahanga River are very high. The alluvial gravel and sand aquifers of the Wairarapa Valley, support productive groundwater aquifers at depths of up to 100 metres below ground while the Ruamahanga River and its tributaries present a further source of water for users. Water is allocated to users via resource consents by Greater Wellington Regional Council (GWRC). With intensifying land use, demand from the surface and groundwater resources of the Wairarapa Valley has increased substantially in recent times and careful management is needed to ensure values are maintained. This paper describes the approach being taken to manage water resources in the Wairarapa Valley and redefine appropriate limits of sustainable water use. There are three key parts: Quantifying the groundwater resource. A FEFLOW numerical groundwater flow model was developed by GWRC. This modelling phase provided a much improved understanding of aquifer recharge and abstraction processes. It also began to reveal the extent of hydraulic connection between aquifer and river systems and the importance of moving towards an integrated (conjunctive) approach to allocating water. Development of a conjunctive management framework. The FEFLOW model was used to quantify the stream flow depletion impacts of a range of groundwater abstraction scenarios. From this, three abstraction categories (A, B and C) that describe diminishing degrees of hydraulic connection between ground and surface water resources were mapped in 3 dimensions across the Valley. Interim allocation limits have been defined for each of 17 discrete management units within the valley based on both local scale aquifer recharge and stream flow depletion criteria but also cumulative impacts at the valley-wide scale. These allocation limits are to be further refined into agreed final limits through a community-led decision making process. Community involvement in the limit setting process. Historically in New Zealand, limits for sustainable resource use have been established primarily on the basis of 'hard science' and the decision making process has been driven by regional councils. Community involvement in limit setting processes has been through consultation rather than active participation. Recent legislation in the form of a National Policy Statement on Freshwater Management (2011) is reforming this approach. In particular, collaborative consensus-based decision making with active engagement from stakeholders is now expected. With this in mind, a committee of Wairarapa local people with a wide range of backgrounds was established in 2014. The role of this committee is to make final recommendations about resource use limits (including allocation of water) that reflect the aspirations of the communities they represent. To assist the committee in taking a holistic view it is intended that the existing numerical groundwater flow models will be coupled with with surface flow, contaminant transport, biological and economic models. This will provide the basis for assessing the likely outcomes of a range of future land use and resource limit scenarios.

• Parasites, Hosts and Diseases
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• v.56 no.2
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• pp.205-210
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• 2018

Waterborne parasitic protozoa, particularly Giardia lamblia and Cryptosporidium spp., are common causes of diarrhea and gastroenteritis worldwide. The most frequently identified source of infestation is water, and exposure involves either drinking water or recreation in swimming pools or natural bodies of water. In practice, studies on Cryptosporidium oocysts and Giardia cysts in surface water are challenging owing to the low concentrations of these microorganisms because of dilution. In this study, a 3-year monitoring of Cryptosporidium parvum, Giardia lamblia, and Naegleria fowleri was conducted from August 2014 to June 2016 at 5 surface water sites including 2 lakes, 1 river, and 2 water intake plants. A total of 50 water samples of 40 L were examined. Cryptosporidium oocysts were detected in 22% of samples and Giardia cysts in 32%. Water at the 5 sampling sites was all contaminated with Cryptosporidium oocysts (0-36/L), Giardia cysts (0-39/L), or both. The geometric mean concentrations of Cryptosporidium and Giardia were 1.14 oocysts/L and 4.62 cysts/L, respectively. Thus, effective monitoring plans must take into account the spatial and temporal parameters of contamination because they affect the prevalence and distribution of these protozoan cysts in local water resources.

• Korean Institute of Interior Design Journal
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• v.23 no.5
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• pp.104-111
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• 2014

This study puts its purpose on presenting an integral system of representative urban landscapes, public design and colors, in practicing urban design in the context of local identity. An integral design of public design that successfully plans and executes local identity, and changes recognition of integral management of urban design, is suggested as followings. Firstly, when the catchment area is divided in metropolitan area, it should be reset according to the natural environment condition regardless of administrative area system like city and county. It is the method to classify the metropolitan area by researching and analyzing geographical condition, weather condition, soil and vegetation in detail and subclassify it by the visual commonness of natural environment. Secondly, it is necessary to access the urban landscape, public design and urban color from the overall aspect emphasizing the plan for each field and local identity. They should be practiced by the role and category of each field on the basis of consistent design strategy and instruction but the cooperation system is required as a process to reinforce and specify the mutual limit. Thirdly, the artificial structure is constructed through artificial adjustment depending on the urban formation process and the development time point. Therefore, it is necessary to pay attention to the rapid urban development, the change speed and the landscape formation of each age. It is necessary to classify the type of artificial landscape by age and form similarity and separate the area that should be generalized and controlled by entire metropolitan area form the area that should be specialized by basic local government.

• Journal of Korean Society of Water and Wastewater
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• v.22 no.2
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• pp.233-238
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• 2008

Recently, rainwater harvesting facilities have increasingly constructed mainly in elementary schools and government buildings. Nevertheless, few methods are available for efficient planning and design of rainwater harvesting facilities by considering the weather conditions and purpose of rainwater management in each site, which may lead to a construction of uneconomic facilities. The current method estimates the size of rainwater storage tank by multiplying the size of building or plottage with a certain ratio and has many limitations. In this study, we first developed a method for planning and design of rainwater storage facilities using $Rainstock^{TM}$ model, which is based on mass balance, and economic analysis. Then, the model was applied for the design of a rainwater harvesting facility in a building with the catchment area of $1,000m^2$. The model calculation indicated that the economic feasibility of rainwater harvesting depends on not only the size of storage tank but also the water usage rate. When the water usage rate is $1m^3/day$, the rainwater harvesting facility is not cost-effective regardless of the size of the storage tank. With increasing the water usage rate, the economical efficiency of the facility was improved for a specific size of the storage tank. Based on the model calculation, the optimum tank sizes for $5m^3/day$ and $10m^3/day$ of water usage rates were $24m^3$ and $57m^3$, respectively. It is expected that the model is useful for optimization of rainwater storage facilities in planning and designing steps.

• Tunnel and Underground Space
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• v.17 no.5
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• pp.360-371
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• 2007

This paper presents an application of drainage control and slope stability by GIS-based hydrological modeling to control the surface water from an operational point of view. This study was carried out on a region of Pasir open-pit coal mine, Indonesia. A detailed topographical survey was performed at the study area to generate a reliable DEM (Digital Elevation Model). Hydrology tools implemented in ArcGIS 9.1 were used to extract the characteristics of drainage system such as flow direction, flow accumulation and catchment area from DEM. The results of hydrological modeling and spatial analysis showed that current arrangement of pumping facility is not suitable and some vulnerable places to erosion exist on the bench face due to concentrated surface runoff. Finally, some practical measures were suggested to optimize the design of drainage system and to monitor the slope stability by the surface water management at the study region during heavy rainfall.

• Journal of Soil and Groundwater Environment
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• v.7 no.4
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• pp.40-47
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• 2002

The practices of the construction and management of the petroleum and hazardous chemical compound storage facilities in Korea were investigated extensively, and the problems were identified. The advanced technologies in the U.S.A were comparatively studied. Considering the effectiveness of leak prevention and applicability, the following measures were suggested. To prevent corrosion of a tank, a clad tank, an interior lining tank, or a double-wall tank were thought to be the most cost effective. For piping. use of non-metalic materials was suggested. A catchment basin seemed to be effective for preventing spills. For monitoring of leaks, constructions of more than one of detection systems, such as an automatic leak detection device. a vapor detection system, a groundwater monitoring system, or a double-wall monitoring system, were recommended.