• Journal of Ecology and Environment
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• v.37 no.3
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• pp.147-153
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• 2014

Structural heterogeneity results in different spatial distributions of microcrustaceans. Thus, in ecosystems with excessive macrophyte development, it may be difficult to determine the microcrustacean species composition. Given the importance of microcrustaceans in the food web, the elucidation of microcrustacean diversity is essential. In vegetated habitats, bluegill sunfish can prey on microcrustaceans, and therefore have a potential role as microcrustacean monitoring agents. In the present study, we compared microcrustacean species compositions in the field with those in the guts of bluegill, in Jangcheok Lake, South Korea. Our results showed that the number of microcrustacean species was higher in bluegill guts than in the field. Further, microcrustacean species, such as Daphnia galeata, Graptoleveris testudinaria, Leydigia leydigii, Rhynchotalona sp., and Simocephalus exponisus, were found only in bluegill guts. Our findings verify the validity of the fish gut analysis to monitor microcrustacean species compositions and to clarify spatial distributions of microcrustacean species in structurally heterogeneous ecosystems with excessive macrophyte development.

• Bulletin of the Korean Chemical Society
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• v.24 no.2
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• pp.209-218
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• 2003

Ecosystems in the Keweenaw Peninsula region of Lake Superior, USA, were disturbed by over 500 million tons of copper-rich mine tailings during the period 1850-1968. Metals leaching from these mine residues have had dramatic effects on the ecosystems. Vast acreages of exposed tailings that are over 100 years old remain unvegetated because of the combination of metal toxicity, absence of nutrients, and temperature and water stress. Therefore, it is important to characterize and fractionate solid copper phases for assessing labile forms of copper in soils and sediments contaminated by the mining wastes. X-ray diffraction analyses indicate that calcite, quartz, hematite, orthoclase, and sanidine minerals are present as major minerals, whereas cuprite,tenorite, malachite, and chalcopyrite might be present as copper minerals in the mining wastes. Sequential extraction technique revealed that carbonate and oxide fractions were the largest pools of copper (ca. 50-80%) in lakeshore and wetland stamp sands whereas the organic matter fraction was the largest reservoir (ca. 32%) in the lake sediments. The concentrations of iron and copper were inversely correlated in the oxide fraction suggesting that copper may occur as a surface coating on iron oxides. As particle size and water contents decrease, the percent of the copper bound to the labile carbonate fraction increases.

• Proceedings of the Zoological Society Korea Conference
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• 2001.10a
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• pp.136.3-137
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• 2001

No Abstract, See Full Text

• Asian Journal of Turfgrass Science
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• v.10 no.2
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• pp.143-150
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• 1996

The removal rates of gross production and organic matters were investigated in the Lake Paldangho. In 1995 and 1996, soils and litter sarraples were collected and annual mean production and removal rates were calculated. Communities in the Lake Paldangho were Phragrnites communis, Miscanthus sacchariflorus, Typha aegustata and Scirpas tahernaemoutani. Removal constants of aquatic plant communities estimated by the mathematical theoretical models, were 0.826, 0.567, 0.571 and 0.751, respectively. The durations of reaching half of initial organic amounts were 0.839 yeras, 1.221 years, 1.213 years and 0.922 years respectively at the steady state of removal and accumulation for organics For organics, the rapidity of removal were more speedy P. communis, S.tahernaemontani, T. augustata, M sacehariflorus in order. The times needed for 99% removal were 6.051 years, 6.651 years, 8.752 years and 8.811 years, respectively. Key wotds:Gross production, Organic matters, Lake Paldangho, Phragmites communis, Mis-ca ethus sacchariflorus, Typha angustata, Scirpus tahernaemoutani., Removal constants.

• Korean Journal of Ecology and Environment
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• v.38 no.spc
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• pp.8-11
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• 2005

Carbon stable isotope ratios of producers varied in lake ecosystems. In tile present study, we tried to estimate the seasonal variations of carbon isotope ratios of phytoplankton and benthic diatoms in a strongly acidic lake ecosystem. Lake Katanuma is a volcanic, strongly acidic lake (average pH of 2.2), located in Miyagi, Japan. Only two algal species dominate in Lake Katanuma; Pinnularia acidojaponica as a benthic diatom, and Chlamydomonas acidophila as a green alga. Carbon isotope values of P. acidojaponica varied seasonally, while those of particulate organic matter, which were mainly composed of C. acidophila remained fairly stable. The differences suggested that $CO_2$ gas was more frequently limited for P. acidojaponica than C. acidophila, since high density patches of benthic diatoms were sometimes observed on the lake sediment. Generally, carbon concentration mechanisms (CCMs)of microalgae can fix bicarbonate in lakes, and affect the carbon isotope values of microalgae. While, in Lake Katanuma, CCMs of the microalgae may scarcely function because of high $CO_2$ gas concentration and low pH. This is the reason for low seasonal amplitude of carbon isotope values of phytoplankton relative to those in other lakes.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.25 no.5
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• pp.77-88
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• 2022

This study aims to understand the relationship between the distribution of fish species in the two water ecosystems and the habitat factors according to the survey period targeting Gwanggyo Lake Park in the city. There are studies on the appearance and distribution of species by applying eDNA to freshwater ecosystems. However, in the domestic, streams are the target, and studies on the relationship between species distribution and habitat environment in two water environments are lacking. We conducted to analyze the species list and relationship with habitat factors using eDNA research in May and October at 21 points in Gwanggyo Lake Park, Suwon City, which were connected to lakes and streams. As a result, there was no species difference in the water environment according to the survey period. However, the total number of reads during the spawning season(May) was 3,126,482, which was more than double that after the spawning season(October). Tolerant species appeared in Woncheon Lake with a slow or stagnant flow, but there was no significant correlation between species and habitat factors depending on the survey period. On the other hand, intermediate and sensitive species appeared in the Woncheon stream with high flow. There was a significant correlation between the low temperature during the spawning season and the high dissolved oxygen content after the spawning season(P<0.001, Tem.: 20.7±2.6℃, DO: 8.6±1.7). It is expected that environmental DNA will be used to survey species and suggest monitoring methods according to the survey period.

• Asian Journal of Turfgrass Science
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• v.11 no.2
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• pp.125-137
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• 1997

Five dictyostelid cellular slime molds were isolated from the littoral grassland ecoystems of the lake Paldangho, safeguard of waterworks, Kyounggi-do, South Korea. They were Poiysphoadylium violceum, Dictyosielium aureo-stipes var. aureo-stipes D crassicaule, D macrocephalum and D gigauteum. P. violaceum was dominant species. It live on the low nutrient and barren soils as the littoral zone destabilized in surface soils, litters and chemicals by inundation an rain precipitation. Key words: Cellular slime mold, Littoral grassland ecosystem.

• Asian Journal of Turfgrass Science
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• v.10 no.2
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• pp.159-166
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• 1996

To estimate removal rate of phosphorus in aquatic grassland ecosystems of Paldangho, this investigation was conducted along with the coast of a lake. The experimental results may be summarized on communities of Typha angustata, Miscanthus sacchriflorus Phragmites communis and Scirpus tabernaemontani as follows. The annual production of phosphorus for the litters in T. angustata, M saccharsflorus, P. cam-munis and S. taiernaemontani grasslands were 10.252 g /$m^2$, 3.833 g /$m^2$, , 2.656 g /$m^2$, and 5.210 g /$m^2$, respectively. The ratio of annual production of P accumulated on surface soils in a steady state provides estimates of the removal rate r, The estimated removal rates r of P were 0.58, 0.78, 0.68 and 0.59 in T. angustata, M. sacchariflorus, P. communis and S. tabernaemontani grasslands re- spectively. The removal and accumulation of 50, 95 and of 99% of its steady state level, the estimates for P of T. angustata were 1.195, 5.173 and 8.623 years, in M. sacchariflorus were 0.880, 3.842, and 6.403 years, and in P. cammunis were 1.014, 4.390, and 7.316 years respectively, In S. tabernaemontani grassland required period were 1.178,5.099 and 8.500. Key words:T. angustata, S. tabernaemantani, P. communis, S. tabernaemontani, Paldangho, Removal rate, Phosphorus.

• ALGAE
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• v.37 no.4
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• pp.301-316
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• 2022

The red alga Compsopogon caeruleus can generally be found in tropical and subtropical waters worldwide. In addition to its natural habitats, this species may be found in waters that receive abnormally hot water, e.g., from powerhouses. To date, the presence of C. caeruleus has not been observed in thermally polluted lacustrine ecosystems in Poland, which has a moderate climate. The thalli of this red alga were found growing on Vallisneria spiralis in Lichenskie Lake. Importantly, this paper presents a previously unknown relationship between the temperature (20, 25, 30, 35, and 40℃) and oxygen requirements of C. caeruleus (based on ex situ measurements of O₂ consumption by thalli). Surprisingly, 35℃ can be the optimum temperature for C. caeruleus, and this temperature is higher than the values reported by some previous thermal analyses by approximately 10℃. Additionally, we reviewed and mapped the distribution of this nonnative and mesophilic red alga in natural / seminatural water ecosystems in Europe. Finally, we propose that the occurrence of C. caeruleus mature thalli can be a novel, simple and easy-to-recognize bioindicator of artificially and permanently heated waters in moderate climate zones by a regular discharge of postindustrial water.

• Korean Journal of Environmental Biology
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• v.22 no.1
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• pp.227-232
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• 2004

Hydrological and biological studies on ecosystems of the lakes 'etang de Berre' and 'etang de Vaime', the four rivers flowing into these lakes, and the Mediterranean Sea are carried out during the whole two-year period. The phytoplankton population of the lakes 'etang de Berre' and 'etang de Vaine' is larger than that of the seawater or freshwater populations of four neighbouring rivers. This is due to the increasing nutriments such as phosphate, nitrate, and silicate flowing into the lakes from the four rivers. The superfluous phytoplanktons in the lakes flow into the Mediterranean Sea via the Caronte Canal. Phytoplanktons multiplicated by phosphate of lake 'etang de Berre' can produce 10,160 tons of assimilated carbon per year, and those multiplicated by nitrate produce 18,450 tons of assimilated carbon per year. According to Steeman Nielsen's primary production estimation, phytoplanktons produce about 45,000 tons of carbon per year through assimilation in lake'4tang de Berre' and 10,000 tons of carbon per year in lake 'etang de Vaime'. The amount of carbon produced by phytoplanktons and the amount of phosphate, and nitrate are different according to the sea, river, and estuary.