• Korean Journal of Fisheries and Aquatic Sciences
• /
• v.44 no.6
• /
• pp.612-621
• /
• 2011

The influences of inland pollution sources because of rainfall events on the bacteriological water quality in Geoje Bay, a major shellfish production area in Korea, were investigated. The sanitary status of sea water and shellfish after rainfall events was also evaluated. The flow rates of 13 streams around Geoje Bay showed 6 to 7-fold increases after 15 to 21 mm of rainfall. Peak pollution was observed in the Naegan Stream, the Gandeok Stream and the Seojeong Stream. The calculated impact area of inland pollution sources was 3.1 $km^2$ immediately after 15 mm of rainfall and expanded to 3.5 $km^2$ after 24 hours. These calculations of impacted area matched results from fecal coliform analyses with sea water. The distance between the major pollution source in the bay (the Gandeok Stream) and the station with the worst bacteriological water quality immediately after 15 mm of rainfall, which was below the Korean standard, was 0.8 km in a straight line; this distance increased to 2.0 km after a period of 24 hours. The area impacted by inland pollution sources after a 15 mm rainfall event was wider than after a 21 mm rainfall. Although the flow rate from inland pollution sources was higher, the concentration of fecal coliform in the discharged water was lower after higher rainfall events. These observations corresponded with the results of fecal coliform analyses with sea water samples. According to the evaluation of the influences of inland pollution sources and fecal coliform analyses on sea water and shellfish samples in Geoje Bay, pollutants from inland sources did not reach the boundary line of the shellfish growing area after rainfall events of 15 or 22 mm. The bacteriological water quality of the shellfish growing area in Geoje Bay met the Korean standard and US NSSP requirements for approved shellfish growing areas.

• The Korean Journal of Ecology
• /
• v.17 no.1
• /
• pp.37-47
• /
• 1994

A study was conducted to examine the leaf expansion forms and to analyze the leaf growth in early growing season of 1992 in a temperate deciduous forest in central region of Korea. After the winter bud scale fell off, the expansion forms of 11 woody species were divided into 3 groups, spreading fan form, opening form from half folding, and unrolling form from main vein. The ratios of leaf area at the end of growing season to that of leaf expantion time varied among species, and were related closely to expansion forms. The leaves reached to full size between the third ten days of April and the middle ten days of May, except for a few species. Leaf weight, however, increased steadily during the growing season. Specific leaf area (SLA) increased rapidly for 10-20 days after leaf expansion and decreased rapidly for 10 days after reaching maximum values, and thereafter decreased slowly. The SLA values of trees were smaller than $200cm^2/g$, but those of subtree and shrub were larger than $200cm^2/g$.

• 한국공간정보시스템학회:학술대회논문집
• /
• 2007.06a
• /
• pp.355-358
• /
• 2007

This paper is aimed that preparing to make good plan for great city ports, like Gwangyang port which is growing rapidly in Asia as a hub port. But I am worrying about the capacity of Gwangyang bay area to serve very great mission for the future, continuously. I hope that we are able to make good circumstances for our great ports. In this Gwangyang bay, we can realize that we may have some solutions for the traffic jam, because of the finite bay area. So I analyzed the rate of traffic jam that was derived from so many great ships to come and use the Gwangyang bay area. As a result, in recent year, 2005, 2006, ratio was growing rapidly, so we need so we need good works for this region.

• Proceedings of the KSRS Conference
• /
• 2002.10a
• /
• pp.702-707
• /
• 2002

Three periods of land-use maps of the Suomo Basin were drawn from topographic maps (1970a) and Landsat TM/ETM images (1986a and 1999a). The area of each kind of land use was calculated from the three maps. From 1970 to 1999, the area of forestland decreased 17%, the area of sparse forestland increased 8%, and the area of grassland increased 10%. The transferring trend of the land-use is that forestland turned into sparse forestland and brush land, and the brush land degenerated into grassland based on the transferring matrixes from 1970 to 1986, and from 1986 to 1999. According to the local government record and statistical data, forest cover rate had been increasing from 1970 to 1998, but the amount of growing stock had been declining. From 1957 to 1998, the amount of growing stock declined from 423m$^3$/ha to 177m$^3$/ha.

• Journal of Korean Society of Forest Science
• /
• v.76 no.1
• /
• pp.27-32
• /
• 1987

Stomatal morphological characteristics (shape, density and length) were investigated for 8 ornamental woody species growing in the campus of Sangji College on Usandong, Wonju, Kangwondo. Stomata of Forsythia koreana, Syringa dialata, Zedkova serrata and Chaenomeles sinensis were classified as irregular-celled type (anomocytic), those of Vibrunum sargentii, Liriodendron tulipifera and Magnolia kobus as parallel-celled type (paracytic). For Forsythia koreana, stomatal length was not greatly changed as the leaf blade, growing larger. Number of stomata per unit leaf area was decreased, but number of stomata per single leaf was increased as the leaf blade, growing larger. For Taxus cuspidata, stomatal length was increased, but number of stomata per unit needle area was decreased as the needle, growing larger.

• Journal of Plant Biology
• /
• v.37 no.3
• /
• pp.309-316
• /
• 1994

To make regional comparisons of water status of pitch pine, the temporal changes of water status in pitch pine were investigated at different areas; urban Seoul (heavily polluted area), surburb of Seoul (lightly polluted area), and rural area (control). The effects of air pollutants, acid rain and chemical properties of soil on water deficit in pitch pine were also investiaged. Water content of needles growing at polluted areas were usually lower than that at unpolluted area. Water saturation deficit of needles growing at polluted areas were usually higher than that at unpolluted area especially in dry season. These results indicated that water in needles growing at polluted areas were usually more deficient than that at unpolluted area, and were more deficient in April than other months. At polluted areas, the older the needles were, the more quickly transpirated the water in the needle was. At unpolluted areas, however, water in old needles was not so quickly transpirated as those at polluted areas. Water potential of needles of pitch pine seedlings treated with simulated acid rain (SAR) of pH 3.5 decreased more quickly than that of needles treated with SAR of pH 5.6. Loss of water through epicuticular layer was greater in the following order: magnesium deficiency＋100 $\mu$M aluminium>100$\mu$M aluminium>magnesium deficiency>control. In addition to Mg deficiency and Al toxicity, growth decline of pitch pine widely occurring in polluated Seoul could to a large extent be due to cuticle degredation and abnormal vertical distribution of fine roots, which lead to water stress, particularly in dry seasons.

• Journal of The Korean Society of Agricultural Engineers
• /
• v.59 no.2
• /
• pp.91-99
• /
• 2017

The objective of this research was to investigate runoff characteristics of suspended solid (SS) and chemical oxygen demand (COD) from a paddy field watershed during storm events in the growing and non-growing seasons. Average of event mean concentration (EMC) of pollutants were 56.9 mg/L for SS and 23.9 mg/L for COD in the non-growing season and 50.3 mg/L for SS and 11.9 mg/L for COD in the growing season. The average EMC of SS in the study area was much lower than that in the uplands irrespective of cultivation, suggesting that paddy fields control soil erosion. This may be because flooding and wet soil in the growing season, and rice straw residue and stubble on the topsoil in the non-growing season reduce soil erosion. The changing tillage practice from fall tillage to spring tillage avoids soil erosion due to shortening of the tilled fallow period. However, the average EMC of COD in the non-growing season was about twice as much that in the growing season likely due to the runoff of organics like rice straw residues. The relationship between SS and COD loads and stormwater runoff volume was expressed by power function. The exponent for SS was higher than that for COD, suggesting that SS load increased with stormflow runoff more than COD load did. The mean SS and COD loads per storm during the non-growing season were much lower than those in the growing season, and therefore non-point source pollution in the growing season should be managed well.

• Journal of agriculture & life science
• /
• v.45 no.3
• /
• pp.35-41
• /
• 2011

The objective of this study was to estimate domestic potential wood supply according to geographical and forest management conditions. In order to separate available wood supply area, analysis was conducted by separating natural, theoretical, geographical and technical supply area. Natural supply area was separated by extract stocked land from forest using digital stock map. Theoretical, geographical and technical supply area was separated by considering protection area, slope, streamside and road. Growing stock was calculated by using species and age-class of digital stock map. Potential wood supply was estimated by calculating growing stock of technical supply area. The results of growing stock of each supply area was shown that growing stock was from 244,150 to 596,248 thousand $m^3$. According to the results of this study, it was found that potential wood supply are likely to be over- or underestimated depending on the considered level of geographical and forest management conditions. Provincial potential wood supply was highly ranked in order of Gyeongbuk, jeonnam, Gyeongnam and Gangwon province.

• Magazine of the Korean Society of Agricultural Engineers
• /
• v.41 no.1
• /
• pp.52-59
• /
• 1999

Paddy rice is semi-tropical crop and requires warmirrigation water. If mean water temperature at the water source during the growing period is below 18$^{\circ}C$, sime kinds of water warming mechanism should be taken. In this study irrigation water temperature is measured and preventive measures to cold water damage on paddy rice are suggested. Field observations were performed at 100ha field area downtream of the Unmoon reservoir during the growing season of 1997. Land use, canal system, water temperature at irrigation canals. reservoir, and paddy fields were observed. In addition, growth and yield of the rice at selected plots were observed. Accordingly to the record, cold water damage occurred in this area due to the cold irrigation water supply in 1996. It did not occur because of the effective irrigation water management practice in 1997. However, several preventive measures such as pontoon intake system, using existing weir and construting a new warming pond, are suggested to prevent cold water damage in the future. If a new warming pond is construted to raise irrigation water temperature by 2 $^{\circ}C$, a pond area of 2.94 ha is required.

• Korean Journal of Remote Sensing
• /
• v.36 no.5_4
• /
• pp.1245-1254
• /
• 2020

In this study, the limitations of the existing water level detection algorithm using CCTV images were recognized and the water level detection algorithm was improved by applying the Region growing technique. It applied three techniques (Horizontal projection profile, Texture analysis, and Optical flow) to estimate the water area, and the results were analyzed in a comprehensive analysis to select the initial water area. The water level was then continuously detected by the Region growing technique, referring to the initial water area. As a result, it was possible to confirm that the exact level of water was detected without being affected by environmental factors compared to the existing level detection algorithm, which had frequent mis-detection phenomena depending on the surrounding environmental factors. In addition, the water level was detected in the video showing flooded roads in urban areas, not in the video of the river. These results are believed to be able to supplement the difficulty of monitoring at all times with limited manpower by automatically detecting the level of water through numerous CCTV footage installed throughout the country, and to contribute to laying the foundation for preventing disasters caused by torrential rains and typhoons in advance.