• Korean Journal of Soil Science and Fertilizer
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• v.48 no.1
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• pp.15-21
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• 2015

The use of cover crops has a beneficial effect on sustainable soil management in pear orchards. We aimed to compare changes in soil chemical properties and biota with the use of different cover crops. We tested the effects of five cover plants, including hairy vetch, orchard grass, rattail fescue, rye, and perennial ryegrass. Use of different cover crops had a minimal impact on soil chemical properties through three year experiments. The aboveground biomass was greatest with the use of rye. The potential amounts of returnable N and P were highest when leguminous hairy vetch was used as a cover plant. Changes in the composition of the microbial community were investigated by phospholipid fatty acid (PLFA) analysis. Microbial PLFAs were highest with the use of rattail fescue and lowest with the use of hairy vetch. Minimal changes in the abundances of nematodes and microarthropods suggested that there was no bottom-up control in the soil ecosystem. The results also show that increases in aboveground biomass and nutrient content with the use of cover crops may not promote the abundance of soil organisms.

• Korean Journal of Ecology and Environment
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• v.57 no.1
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• pp.51-59
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• 2024

This note summarizes the application of zooplankton indices for water quality management and estimation based on main research topics of articles focusing on wetland ecosystems, topics that are remained poorly investigated in S. Korea. The aquatic ecosystem-based consists of indices that respond to different target environmental factors, including environmental disturbance. Among the major indicator species and biota, we reviewed that management strategy for the wetland environment has to be focused more on small-sizes, in terms of zooplankton ecology and indices. The ecology of zooplankton communities in freshwater ecosystem has been the focus of an increasing number of studies since 2019, and considerable progress has been made in understanding the major mechanisms involved in regulating their abundance, diversity and spatio-temporal patterns. Even though studies on the freshwater ecosystem in Korea have a long history, a few of studies on zooplankton biota were conducted at wetlands. We suggested the candidate zooplankton indices proposed by the U.S. EPA and EU to suit Korean conditions. In the step of selecting metrics, the best available metrics are species-related variables, such as composition and abundance, as well as richness and diversity. Overall, in spite of several limitations, the development of a plankton-based multivariate assessment method in Korea wetlands is possible using mostly field research data. Later, it could be improved based on qualitative metrics on zooplankton, and with the emergence of further survey data. The present information can be used as basic information for researchers who are dealing with aquatic environments and its interaction with organisms.

• Korean Journal of Environment and Ecology
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• v.32 no.4
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• pp.425-439
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• 2018

W investigated the environmental factors and inhabiting biota such as macrophytes and zooplankton in 43 sites located on Jeju Island from May and June 2017 to evaluate the spread and ecosystem risk of dotted duckweed (landoltia punctata) which was recently found for the first time in Jeju Island. Dotted duckweeds were found in a total of 18 sites which tended to show low biomass of aquatic macrophyte species other than the dotted duckweed. We conducted a pattern analysis using SOM (Self-Organizing Map), which extracts information through competitive and adaptive properties, to analyze the effect of inhabiting biota on aquatic macrophytes such as the dotted duckweed and environmental factors. The SOM analysis showed that the inhabiting biota such as the zooplankton affected the biomass of aquatic macrophytes than they did the environmental factors. In particular, the biomass of dotted duckweed was positively related to plant-attached species (Alona, Chydorus, and Pleuroxus). Considering that low density of aquatic macrophytes covers the streams and wetlands on Jeju Island because of irregular water source and sharp change of water depth, the dotted duckweeds are likely to play an essential role as the vital habitat for micro-biota including zooplankton in wetlands and streams on Jeju Island. Furthermore, considering that organic matters are utilized as the primary food source in the areas occupied by dotted duckweed, dotted duckweeds have the role of being both habitat and food source. Although the dense growth of dotted duckweed adversely affects growth and development of some aquatic plants due to the shadow effect, it is due to the dominance of floating plants on the water surface should not be regarded as the risk of the dotted duckweed. In conclusion, the dotted duckweeds have spread and settled in most of the water systems on Jeju Island, their impact on inhabiting biota and the aquatic environment was minor. It is necessary to monitor the distribution and spread of dotted duckweeds in the inland areas outside of Jeju Island in the future.

• Korean Journal of Environmental Biology
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• v.17 no.4
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• pp.407-414
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• 1999

Distribution of biota and removal efficiency of organic matter in natural wetland systems were examined from June to October 1998. The aquatic macrophyte communities were consisted of 13 families and 22 species. The composition of occurrence species were as follows: Phragmites communis Trinius are 35%, Persicaria thunbergii Nakai are 19%, Typha angustifolia L. are 17%, Bidens tripartita L. are 16%, Echinochloa crus-galli (L.) Beauv. are 12% and others are l％. The fauna collected from 5 sites consisted of total 6 classes of macroinvertebrates. The composition of occurrence classes were as follows: Insecta are 76%, O1igochaeta are 19%, Gastrapoda are 4％ and others are 1%. These included 18 families, 7 orders of Insects. The larve and mosquito and midges were found in wetlands. Preventive strategies are needed for the suppression of mosquito at the stage of wetland planning and design. In wetland, removal efficiency of dissolved organic carbon is low because of primary production and the background level of DOC in the wetland discharge seems to be 5 mgC/1, but those of BOD was ca. 50%. Wetlands receiving water of low concentration can not work as purification field.

• Korean Journal of Ecology and Environment
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• v.51 no.1
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• pp.40-59
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• 2018

This review summarizes the history of freshwater zooplankton research in Korean Society of Limnology and necessary future topics that are remain poorly investigated in South Korea based on main research topics of published articles focusing on lakes, reservoirs, rivers and wetland ecosystems. In Korea, a total 450 freshwater zooplankton species have been reported (85 species of cladocera, ca. 230 species of rotifera since 1939, and 138 species of copepoda), and they cover 10% of total zooplankton species list. In the present paper, we provide recent species list of zooplankton found in Korea and their taxonomic keys. Over periods of 45 years, there are 25 published papers for zooplankton biota in lentic ecosystems in Korean Journal of Ecology and Environment (KJEE). The ecology of zooplankton communities in rivers has focused on the mechanisms involved in regulating their abundance, diversity and spatio-temporal patterns of genus Bosmina and rotifers (genus Brachionus and Keratella) that are most frequently found from Korea. On the other hand, the studies on zooplankton in wetland has focused on Alona, Chydorus and Ceriodaphnia with special emphasis on their relationships with aquatic macrophytes. Even though studies on the freshwater ecosystem in Korea have a long history, a few of studies on zooplankton biota were conducted at rice paddy, Dumbeong and wetlands. During the last two decades, experimental advances in freshwater zooplankton ecology and understanding of structure and function of this biota were made from a series of articles mainly in journal of KJEE. For future studies, quantitative, experimental and interdisciplinary approaches would be key words to understand zooplankton ecology and their roles in aquatic ecosystems under changing environments, and we have suggested necessary zooplankton research fields and future directions.

• 한국약용작물학회:학술대회논문집
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• 2011.04a
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• pp.444-445
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• 2011

• 한국약용작물학회:학술대회논문집
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• 2011.09a
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• pp.366-367
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• 2011

• Journal of the speleological society of Korea
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• no.7
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• pp.15-24
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• 1998

Conservation is the optimum sustained use of natural resources; therefore, cave conservation must provide not only for the protection of the character, decoration and biota of caves, but also for the means whereby people might enjoy and understand the caves that are their heritage. A cave is a natural subterranean cavity into which a man can enter to a point where daylight cannot be seen. Caves are not only interesting physical entities that provide distinctive sensory and perceptual experiences and invoke a variety of responses, but they also provide unique opportunities for scientific study. Speleology is the study of caves, and in New Zealand it attracts workers from many disciplines of the universities and government research establishments.(omitted)

• Proceedings of the Korean Society of Applied Pharmacology
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• 1998.11a
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• pp.21-21
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• 1998

Many of world's most successful and commercially-valuable medicines have been derived, directly or indirectly, from natural product sources. Scientists seeks to continue this trend by drawing upon the unique and extensive biota to discover new molecules with potential for development as new medicines. In attempting to generate as much chemical diversity as possible, there is a strategic emphasis on maximizing diversity at five key stages of the process.

• Journal of Soil and Groundwater Environment
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• v.24 no.6
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• pp.16-25
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• 2019

Anthropogenic polycyclic aromatic hydrocarbons (PAHs) are formed by the incomplete combustion of fuels and industrial waste. PAHs can be widely exposed to the environment (water, soil and groundwater). PAHs are potentially toxic, mutagenic and/or carcinogenic. Fundamental studies such as biota uptake (e.g., earthworm and plant) of PAHs are highly needed. It is necessary to develop alternative ways to evaluate bioavailability of PAHs instead of using living organisms because it is time-consuming, difficult to apply in the field, and also exaction method is tedious and time-consuming. In this study, sorption behaviors of phenanthrene were evaluated to predict the fate of PAHs in soils. Moreover, bioaccumulation of PAHs in an artificially contaminated soil was evaluated using pea plant (Pisum sativum) as a bioindicator. A novel passive sampler, organic-diffusive gradient in thin-film (o-DGT) for PAHs was newly synthesized, tested as a biomimic surrogate and compared with plant accumulation. Sorption partitioning coefficient (K_P) and sorption capacity (K_F) were in the order of natural soil > loess corresponding to the increase in organic carbon content (f_oc). Biota-to-soil accumulation factor (BSAF) and DGT-to-soil accumulation factor (DSAF) were evaluated. o-DGT uptake was linearly correlated with pea plant uptake of phenanthrene in contaminated soil (R²=0.863). The Tenax TA based o-DGT as a biomimic surrogate can be used for the prediction of pea plant uptake of phenanthrene in contaminated soil.