• Korean Journal of Soil Science and Fertilizer
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• v.42 no.1
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• pp.21-28
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• 2009

Detailed information on soil characteristics is of great importance for the use and conservation of soil resources that are essential for human welfare and ecosystem sustainability. This paper introduces soil inventory of Korea focusing on national soil database establishment, information systems, use, and future direction for natural resources management. Different scales of soil maps surveyed and soil test data collected by RDA (Rural Development Administration) were computerized to construct digital soil maps and database. Soil chemical properties and heavy metal concentrations in agricultural soils including vulnerable agricultural soils were investigated regularly at fixed sampling points. Internet-based information systems for soil and agro-environmental resources were developed based on 'National Soil Survey Projects' for managing soil resources and for providing soil information to the public, and 'Agroenvironmental Change Monitoring Project' to monitor spatial and temporal changes of agricultural environment will be opened soon. Soils data has a great potential of further application in estimation of soil carbon storage, water capacity, and soil loss. Digital mapping of soil and environment using state-of-the-art and emerging technologies with a pedometrics concept will lead to future direction.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.18 no.4
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• pp.206-213
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• 2013

Glass eels (Anguilla japonica) are caught in the west coast of Korea on their migratory route from the breeding grounds in the Mariana Trench along the North Equatorial Current and the Kuroshio Current. To identify the food source of natural glass eels, we analyzed the stable C and N isotopes of glass eels caught in April 2012 and investigated possible food sources in the survey area. In particular, with respect to the stable C and N isotopes of particulate organic matter, we extended the surveying area to the northern parts of East China Sea as well as the west coast of Korea. The stable C and N isotope ratios of the glass eels caught in the west coast were found to be $-20.7{\pm}0.1$‰ and $5.0{\pm}0.2$‰, respectively. The stable C and N isotope ratios of the particulate organic matter in the west coast of Korea, in which the glass eels are assumed to eat the particulate organic matter as food source, were estimated to be $-24.0{\pm}0.3$‰ and $2.8{\pm}0.4$‰, respectively. Similar data were obtained from the northern part of the East China Sea, $-24.5{\pm}0.5$‰ and $0.8{\pm}0.3$‰. The stable isotope ratios showed values differing from the stepwise increasing rates up the food web in natural aquatic ecosystem, showing that particulate organic matter in the west coast of Korea and East China Sea was not served as the glass eels food source. This result suggested that the glass eels caught in the west coast might not assimilate nutrition from the marine environment during long migration.

• Journal of Wetlands Research
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• v.25 no.3
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• pp.184-195
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• 2023

To develop an effective management plan for Ambrosia trifida L., an invasive alien plant in Korea, we assessed the potential of Ophraella communa LeSage as a biological control agent. This involved investigating the host specificity of the herbivore Ophraella communa LeSage, its annual travel distance, and the impact of this insect on the fitness of Ambrosia trifida L. We confirmed the host plant preference of Ophraella communa LeSage. The travel distance of this insect was determined by monitoring its appearance in selected Ambrosia trifida L. communities without these insects at distances of 10, 20, 30, and 100 meters, based on the locations where the presence of Ophraella communa LeSage was observed. The growth, reproductive, and physiological responses of Ambrosia trifida L. were measured according to feeding by Ophraella communa LeSage. As a result, Ophraella communa LeSage fed on only three taxa and moved short distances within a radius of 30 m per year from the host. The feeding behavior of the herbivore had a negative impact on the growth, reproductive, and physiological responses of Ambrosia trifida L. And the plant's growth and reproduction improved with increasing distance from the herbivore. Furthermore, the introduction of herbivores was able to control over 90% of Ambrosia trifida L. when the coverage of the Ambrosia trifida L. group was below 50%. However, the effectiveness of the removal decreased when the coverage exceeded 90%. These results are likely to be utilized by Ophraella communa LeSage as an ecological control agent. It is advantageous to introduce them in spring (May) when the coverage is low to maximize the effectiveness of control.

• Korean Journal of Environment and Ecology
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• v.37 no.4
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• pp.235-250
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• 2023

This study was carried out to identify the vascular flora of Mt. Bonghwa in the Baekdudaegan Mountain range, located on the border between Namwon City and Jangsu Country in Jeollabuk Province and Hamyang Country in Gyeongsangnam Province and use them as basic data for the conservation of plant diversity and prevention of the spread of alien plants. Specimens deposited at the Herbarium of Korea National Arboretum (KH) were reexamined, and 15 field surveys were conducted from April 2020 to July 2023. The result revealed a total of 466 taxa, consisting of 97 families, 279 genera, 409 species, 16 subspecies, 32 varieties and 9 forms, Of which, eight taxa were endemic plants, and one taxon, Aconitum coreanum (H.Lév.), belonged to the vulnerable (VU) on the national red list species. Moreover, there were 57 floristic target species, including 1 taxon of grade V, 9 taxa of grade III, 14 taxa of grade II, and 33 taxa of grade I, whereas there were 24 taxa of alien plants and 1 taxon of ecosystem disturbance species. In the usefulness survey, 353 taxa were for food, 3 for textiles, 71 for medicinal use, 21 for ornamental use, 108 for pasture use, 2 for industrial use, 7 for miscellaneous use, and 11 for timber plants.

• Korean Journal of Environmental Agriculture
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• v.40 no.4
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• pp.279-289
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• 2021

BACKGROUND: Recently, the golden apple snail, Pomacea canaliculata has been used as an environmentally-friendly weed-control agent in rice farming. Although effective for this particular style of farming, P. canaliculata can be destructive to other crops. The objective of this study was to identify overwintering as well as regional and seasonal distribution characteristics of P. canaliculata. Notably, winter is typically fatal for P. canaliculata. However, owing to increasing average global temperatures, we assessed the ability of P. canaliculata to survive through uncharacteristically warm winters. METHODS AND RESULTS: To examine the distribution and overwintering regions of P. canaliculata, We conducted a survey from April 2020 to May 2021 on environmentally-friendly rice fields, agricultural waterways, and streams in 23 cities belonging to 8 provinces. In addition, because air temperature may influence the distribution density of P. canaliculata, we analyzed the winter temperature data (http://weather.rda.go.kr). CONCLUSION(S): In 2021, overwintering of P. canaliculata (1-3 individuals/m²) was observed in the Goheung and Yeongam regions in Jeonnam. Overwintering of P. canaliculata was observed in fewer regions in 2021 than in 2020; this fact may be attributed to the lower minimum temperatures measured in 2021 (approximately 8℃ lower) than those in 2020. Our results suggest that overwintering occurs as long as overnight temperatures are ≥ -15℃, but can take place if temperatures are as low as -19℃.

• The Korean Journal of Quaternary Research
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• v.17 no.2
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• pp.163-163
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• 2003

The study area, Kwangneung Experiment Forest (KEF) is located on the west-central portion of Korean peninsula and belongs to a cool-temperate broadleaved forest zone. At the old-growth deciduous forest near Soribong-peak (533.1m) in KEF, we have established a permanent plot and a flux tower, and the site was registered as a KLTER site and also a KoFlux site. In this study, we aimed to present basic ecological characteristics and synthetic data of carbon budgets and flows, and some monitoring data which are essential for providing important parameters and validation data for the forest dynamics models or biogeochemical dynamics models to predict or interpolate spatially the changes in forest ecosystem structure and function. We made a stemmap of trees in 1 ha plot and analyzed forest stand structure and physical and chemical soil characteristics, and estimated carbon budgets by forest components (tree biomass, soils, litter and so on). Dominant tree species were Quercus serrata and Carpinus laxiflora, and accompanied by Q. aliena, Carpinus cordata, and so on. As a result of a field survey of the plot, density of the trees larger than 2cm in DBH was 1,473 trees per ha, total biomass 261.2 tons/ha, and basal area 28.0 m2/ha. Parent rock type is granite gneiss. Soil type is brown forest soil (alfisols in USDA system), and the depth is from 38 to 66cm. Soil texture is loam or sandy loam, and its pH was from 4.2 to 5.0 in the surface layer, and from 4.8 to 5.2 in the subsurface layer. Seasonal changes in LAI were measured by hemispherical photography at the l.2m height, and the maximum was 3.65. And the spatial distributions of volumetric soil moisture contents and LAIs of the plot were measured. Litterfall was collected in circular littertraps (collecting area： 0.25m2) and mass loss rates and nutrient release patterns in decomposing litter were estimated using the litterbag technique employing 30cm30cm nylon bags with l.5mm mesh size. Total annual litterfall was 5,627 kg/ha/year and leaf litter accounted for 61% of the litterfall. The leaf litter quantity was highest in Quercus serrata, followed by Carpinus laxiflora and C. cordata, etc. Mass loss from decomposing leaf litter was more rapid in C. laxiflora and C. cordata than in Q. serrata litter. About 77% of C. laxiflora and 84% of C. cordata litter disappeared, while about 48% in Q. serrata litter lost over two years. The carbon pool in living tree biomass including below ground biomass was 136 tons C/ha, and 5.6 tons C/ha is stored in the litter layer, and about 92.0 tons C/ha in the soil to the 30cm in depth. Totally more than about 233.6 tons C/ha was stored in DK site. And then we have drawn a schematic diagram of carbon budgets and flows in each compartment of the KEF site.

• Journal of Environmental Science International
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• v.19 no.3
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• pp.343-351
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• 2010

Since the effect of environmental education at class using textbooks or materials related to environment is limited, the importance of activities for field experience is getting increased day by day. Thereby, the education tends to change into the type of education providing students with direct environmental experience. Students attending the science high school have excellent aptitude and ability for science and will lead the development of science in the future. Now it is urgent to develop various experiential programs which are helpful for them to establish desirable values on environment. However, the field of environmental education that allows science high school students equipped with ample environmental knowledge to improve environment sensitivity and have proper environment awareness is quite restricted as of now. Natural exploration activities are the programs which provide science high school students having lack of chance for environmental education with good opportunities to contact nature and also play significant roles in arousing their interest in issues related with environment. Therefore, it is thought that they will let science high school students explore the natural features of Korea, understand the importance of preserving environment and ecosystem profoundly, and encourage environmental awareness and will of environmental practice. Thereupon, with the study subjects of 121 first and second graders at U Science High School, this article analyzed their recognition of the necessity for environmental education and environmental pollution problems before and after the natural exploration activities, and conducted a survey on their satisfaction after the natural exploration activities and analyzed it. The result of this research is as follows. First, it was shown that the natural exploration activities were effective to raise the science high school students' awareness of issues related with environmental pollution. Second, the natural exploration activities had effect upon enhancing the students' willingness of environmental practice. Third, there was statistically significant correlation between the science high school students' satisfaction with the natural exploration activities and their achievement in the science subject. Fourth, there also was a statistically non or weakness significant correlation between their satisfaction with the natural exploration activities and preference for the science subject. In particular, it was found that students preferring biology indicated higher satisfaction.

• Korean Journal of Environmental Biology
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• v.34 no.3
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• pp.151-160
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• 2016

To understand size fractioned chlorophyll a and material cycles of coastal ecosystem in Uljin marine ranching area (JMRA) of East Sea, 4 times of survey were conducted from April to November 2008. Picoplankton, nanoplankton and netplankton in the surface of UMRA fluctuated with an annual mean of $0.26{\mu}g\;L^{-1}$ between the lowest value of $0.03{\mu}g\;L^{-1}$ and the highest value of $0.87{\mu}g\;L^{-1}$, annual mean $1.32{\mu}g\;L^{-1}$ between $0.11{\mu}g\;L^{-1}$ and $5.60{\mu}g\;L^{-1}$, annual mean $0.45{\mu}g\;L^{-1}$ between no detected (nd) and $4.68{\mu}g\;L^{-1}$, respectively. And the relative ratio of picoplankton, nanoplankton and netplanktons on the phytoplankton biomass was on annual average 12.9%, 65.0% and 22.1%, respectively. The 10 m layer was similar to the surface. The relative ratio of pico- and nano-plankton was higher throughout the year. That is, the material cycle of UMRA consists of a microbial food web rather than traditional food chain at a lower trophic levels. Primary production is deemed to have a higher possibility of being adjusted by top-down dynamics, such as micro-zooplankton grazing pressure rather than nutrients supply.

• Journal of the Korean association of regional geographers
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• v.13 no.2
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• pp.129-142
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• 2007

The Purpose of this study is to evaluate the value of abandoned paddy fields as wetland ecosystems and their suitability as habitats for various species. Physical and chemical characteristics of soils and the change of vegetation in paddy fields were analysed -with the passage of time after cease of cultivation. The results of analyses for soil characteristics, vegetation succession, and functional values of abandoned paddy fields as wetlands were as follows: First, top soils become coarser as years after abandonment increase. Second, as the years of abandonment passed. there were significant differences in organic matter, available phosphorate and calcium, while not in magnesium and cation exchange capacity(CEC). Third, species increased from early stage till middle stage, and decreased in late stage. In similarity analysis of species composition, sites were classified into three groups according to the stage of succession. Upper and lower terraces at Daetgol were classified as early stage of succession. The 1st, 2nd and 3rd terraces at Nonbanggol were in middle stage, while tile 4th and 5th were in late stage. Forth, according to evaluation sheets of MoE and RAM(Rapid Assessment Method) standards, me overall average of functional value of Nonbanggol site were 2.13, classified as "common".

• Ecology and Resilient Infrastructure
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• v.2 no.2
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• pp.108-117
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• 2015

This study was carried out to assess problems related to legislative regulations and guidelines concerning some biological assessment systems applied to stream corridor in Korea. We comparatively reviewed the law of stream corridors and the guidelines for master plan concerned, and the law of water quality and health assessment criteria for the aquatic ecosystem concerned. Stream environments were not managed effectively due to the absence of detail regulations and the criteria for stream assessment. A biological assessment system was not equivalently integrated within the management of water resources in process implementation of projects resulting from the dualistic management system for stream corridors in Korea. The current biological assessment system was reflected to mainly physical habitats or only oriented to some aquatic species correlated with water quality. This system was also recognized as part of environment impact assessment based on an intensive survey method of most biological taxa. Conclusively rapid and quantitative assessment techniques based on advanced organisms, such as vegetation, fish and birds, etc. should be urgently provided for considering as representative indicators of stream conditions in Korea.