• Journal of Korean Society of Forest Science
• /
• v.56 no.1
• /
• pp.82-89
• /
• 1982

The author of this paper has participated for research on soil conservation and watershed management for two years as an associate Personnel at the Inter-American Institute for Co-operation on Agriculture (IICA-OAS), in Jamaica. This paper is fundamentally based on the author's experience of researches as well as the results of studies with the references cited. The island of Jamaica having $11,440km^2$ was divided into 33 groups of watersheds and eighteen watersheds were identified as severely disturbed areas of mostly upstream. There are approximately 164,000 ha of land in urgent need of rehabilitation and protection including a 36,900 ha of five watersheds first priority needed. A national programme of watershed management to conserve all the watersheds, particularly those inhabited by small farmers is urgently necessary.

• Journal of Environmental Impact Assessment
• /
• v.18 no.4
• /
• pp.235-243
• /
• 2009

Wetlands considered to be an important natural resources because they provide biodiversity and habitat for species to breed and survive. In this regard, many countries in the world provide wetlands and have policies and laws to protect them. In Korea we hosted RAMSAR COP-10 at Changwon in 2008 representing Korea's endeavor to wetland protection. But, in the process of development Wetlands are easy target to be lost due its easy access and the laws and regulations to protect them are relatively weak. Thus, this research focused on the introduction of No Wetland Loss(NWL) and we can achieve wetland protection in the economy market ways. Thus, NWL should consider 1) a clear definition of NWL and harmony and consensus of introduction of NWL, 2) considering most wetlands be private we need a financial support for securing wetlands, 3) inventories for wetlands in Korea, draw a line of demarcation, technic to evaluate wetlands, 4) wetland restoration considering function of ecosystem not total amount of wetlands. Wetland protection should be a part of Basic Law of Water Management which in its progress and we need further studies on wetland protection because of watershed management, deserted agricultural paddies, etc.

• Journal of Korean Society of Forest Science
• /
• v.111 no.1
• /
• pp.72-80
• /
• 2022

In this study, intention type was assigned to determine appropriate conservation and use of the Baekdudaegan Protection Area. To determine intention type, 84 indices were integrated into 7 types: the Natural Environment Protection District, Natural Scenic District, Agriculture and Forestry Promotion District, Living Environment Protection District, Education/Culture/Arts Promotion District, Recreation/Tourism Promotion District, and Disaster Management District. Intention types were decided by comparing the occupying proportion of the intention types for each watershed segment in which the Seoraksan, Taebaeksan, and Sockrisan region boundaries were included. Weight values were applied to each of the seven intention types because each type did not play an equal role in the target regions. Most regions were classified as Natural Environment Protection intention types because the Baekdudaegan area is regulated with strong forestry and environmental protection acts; thus, the weight values related to nature protection were higher than those for other types. To supplement the results from this study, additional research is needed to determine the intention type and weight for each region, and it will also be necessary to integrate sociocultural factors and field survey data.

• Journal of the Korean Association of Geographic Information Studies
• /
• v.9 no.4
• /
• pp.215-223
• /
• 2006

The Total Maximum Daily Load(TMDL) Act just implemented as a new tool of watershed based water quality management, in Korea. Thus, there are a number of pending questions to resolve for successful settlement of the TMDL. The allocation of pollution source is a exceedingly sensitive issue on local development planning. The simple area-based allocation (SAA) is conventional method to allocate the administrational pollution information to watershed based information. The SAA has a limitation that it can't consider the characteristics of spatial distribution of pollution source and it has caused more uncertainty of TMDL. This study was performed to reduce the uncertainty of watershed-based pollution information using the spatial distribution-based allocation(SDA). In the specific area where pollution source is concentrated such as urbanized region, it has been certified that SDA could reduce a tolerance of pollution information dramatically. As a result of study, SDA is expected a effective tool for TMDL and to solve the conflict between development and protection.

• KSCE Journal of Civil and Environmental Engineering Research
• /
• v.26 no.1B
• /
• pp.89-98
• /
• 2006

In this study, a method for flood runoff analysis in main channel connected with interior floodplain, is applied for evaluation of hydraulics of Sapgyo lake for the purpose of flood protection by considering tidal effect of West Sea and runoff from the watershed. Especially, operational condition of sluice gate was explicitly modeled in conjunction with various runoff scenarios from watershed. The change in hydraulics of main channel and interior floodplain was found to be predominantly affected by tidal effect, and explicit modeling of gate operation made possible the evaluation of hydraulic characteristics of different alternatives. Until now, such an analysis was not made due to the lack of models with such capability, however, with the proposed method, it is possible to perform such an analysis and is thought that the proposed method can be a valuable tool for flood protection planning.

• Environmental Engineering Research
• /
• v.14 no.4
• /
• pp.200-210
• /
• 2009

The modern era of water quality modeling in the United States began in the 1960s. Pushed by advances in computer technology as well as environmental sciences, water quality modeling evolved through five broad periods: (1) initial model development with mainframe computers (1960s - mid 1970s), (2) model refinement and generalization with minicomputers (mid 1970s - mid 1980s), (3) model standardization and support with microcomputers (mid 1980s - mid 1990s), (4) better model access and performance with faster desktop computers running Windows and local area networks linked to the Internet (mid 1990s - early 2000s), and (5) model integration and widespread use of the Internet (early 2000s - present). Improved computer technology continues to drive improvements in water quality models, including more detailed environmental analysis (spatially and temporally), better user interfaces and GIS software, more accessibility to environmental data from on-line repositories, and more robust modeling frameworks linking hydrodynamics, water quality, watershed and atmospheric models. Driven by regulatory needs and advancing technology, water quality modeling will continue to improve to better address more complicated water bodies and pollutant types, and more complicated management questions. This manuscript describes historical trends in water quality model development in the United States, reviews current efforts, and projects promising future directions.

• Journal of Korean Society on Water Environment
• /
• v.23 no.6
• /
• pp.985-992
• /
• 2007

There are about 40,000 chemicals used in Korea and 300 new types of chemicals are added to the list every year, influencing quality of air, soil and water. Water quality standards that serve as the basis for water quality management have been proved inefficient and insufficient compared to those of advanced countries. This study aims to improve the existing water quality standards. Most importantly, the water quality standards need to take into account not only protection of human health but also aquatic resources. To that end, water quality criteria need to be set by monitoring each watershed every year and conducting risk assessment. Criteria for human health are set at $10^{-6}$ cancer risk level, and for aquatic life at conservative level, adopting the methodology of the U.S. and Australia, respectively. After carrying out technical and economic feasibility studies, more conservative criteria will be used to decide final water quality standards. The development of this system to establish integrated water quality standards for both human health and aquatic resources protection is urgently needed.

• Korean Journal of Ecology and Environment
• /
• v.39 no.2 s.116
• /
• pp.187-197
• /
• 2006

A mathematical modeling program called Hydrological Simulation Program-FORTRAN (HSPF) developed by the United States Environmental Protection Agency(EPA) was applied to the Yongdam Watershed to examine its applicability for loading estimates in watershed scale. It was run under BASINS (Better Assessment Science for Integrating point and Nonpoint Sources) program, and the model was validated using monitoring data of 2002 ${\sim}$ 2003. The model efficiency of runoff was high in comparison between simulated and observed data, while it was relatively low in the water quality parameters. But its reliability and performance were within the expectation considering complexity of the watershed and pollutant sources and land uses intermixed in the watershed. The estimated pollutant load from Yongdam watershed for BOD, T-N and T-P was 1,290,804 kg $yr{-1}$, 3,753,750 kg $yr{-1}$ and 77,404 kg $yr{-1}$,respectively. Non-point source (NPS) contribution was high showing BOD 57.2%, T-N 92.0% and T-P 60.2% of the total annual loading in the study area. The NPS loading during the monsoon rainy season (June to September) was about 55 ${\sim}$ 72% of total NPS loading, and runoff volume was also in a similar rate (69%). However, water quality was not necessarily high during the rainy season, and showed a decreasing trend with increasing water flow. Overall, the BASINS/HSPF was applied to the Yongdam watershed successfully without difficulty, and it was found that the model could be used conveniently to assess watershed characteristics and to estimate pollutant loading in watershed scale.

• Korean Journal of Agricultural and Forest Meteorology
• /
• v.12 no.3
• /
• pp.197-206
• /
• 2010

To provide baseline information essential for assessing environmental impacts of monsoon rainfalls in a mountainous watershed under mixed land use, we investigated spatiotemporal variations in water quality using a combined approach of seasonal water quality survey and intensive storm samplings. Biannual water sampling at nine locations encompassing major land use types showed generally lower electrical conductivity and Cl- concentrations during the typical wet period compared to the dry period, indicating rainfall-induced dilution of dissolved ions. Total metal concentrations, however, were significantly higher during the monsoon period, probably associated with rainfall-induced increases in suspended sediments. Intensive storm sampling during a small monsoon rainfall event (18 mm) and an extreme event (452 mm) showed rapid changes in both suspended sediments and dissolved solutes in an agricultural stream draining the Haean Basin where arable lands have expanded rapidly over the recent decades. By contrast, a nearby forest stream derived from North Korea showed little responses to the small event compared to larges changes during the extreme event. In the agricultural stream total Pb concentrations showed significant positive relationships with suspended sediments. Although limited sampling frequency and locations require a cautious interpretation, the overall results suggest that expansion of agricultural fields in steep mountainous watersheds can increase the susceptibility of soil erosion and its off-site environmental impacts under increasing rainfall variability and extremes.

• Journal of Environmental Science International
• /
• v.7 no.4
• /
• pp.451-460
• /
• 1998

The objectives of this study Is to evaluate the total runoff yield, peak flow and peak flow travel time depending on the urbanization, return period and rainfall patterns at the downstream of Manchon urban watershed in TaeGu City. SWM(Storm Water Management Model) is used for runog analysis based on 5 different steps of urbanization and 4 different types of Hufrs quartile according to 8 return periods. It is analyzed that the order of total runoff yield according to raiun patterns is Huffs 4, Huffs 2. Huffs 3 and Huffs 1 quartile, that of peak flow magnitude is Huffs 2, Huffs 1, Huffs 4 and Huffs 3 quartile at present development ratio. under the 60, 70, 80 and 90ft of urbanization to the 50% of urbanization by means of the rainfall patterns, the mean Increasing ratio of total runoff yield for each case is 4.55, 11.43, 16.07 and 20.02%, that of peak flow is 5.82, 13.61, 17.15 and 18.83%, the mean decreasing ratio of peak flow travel time Is 0.00, 2.44, 5.07 and 6.26%, the mean increasing ratio of runoff depth Is 4.51, 11.42, 16.02 and 20.05% respectively. the mean increasing ratio of total runoff yield by means of each and 19.71%. Therefore, as the result of this study. it can be used for principal data as to storm sewage treatment and flood damage protection planning in urban small watershed.