• Journal of Plant Biology
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• v.22 no.1_2
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• pp.45-51
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• 1979

From 32 angiosperm species, pollen surface characters such as sculpture pattern, roughness, oil abundance and stickiness were subjectively scored, and compared with size and weight of the grains, and pollination mechanisms. There was a linear relationship between size and weight of the grains. Animal-pollinated grains showed significantly higher roughness, oil abundance and stickiness than wind-pollinated grains. In the former, the grain size was highly correlated with roughness and oil abundance. No such relationship was found in the latter. It was suggested, therefore, that the large the animal-pollinated grains, the greater is the stickiness required, where the stickiness depends on the surface soil abundance and roughness. No functional significance of the sculpture pattern could not be detected in this study.

• The Bulletin of The Korean Astronomical Society
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• v.44 no.1
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• pp.68.4-68.4
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• 2019

It is inferred that many stars in the Galactic halo or bulge were once members of globular clusters (GCs), which are now dissolved. To distinguish the GC-originated stars, which can provide valuable information on the origin of the bulge and halo, from the in situ field stars, the Na abundance plays an important role. However, the interstellar Na in certain directions can unnecessarily enhance the estimate of the Na abundance from stellar spectra due to blended Na D lines unless the spectral resolution is very high, which allows to resolve the lines from the interstellar Na. In this study, we present a means of correcting the Na abundance affected by the interstellar Na in the low-resolution of the Sloan Digital Sky Survey stellar spectra.

• Asian-Australasian Journal of Animal Sciences
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• v.2 no.3
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• pp.548-549
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• 1989

• Korean Journal of Environmental Biology
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• v.29 no.4
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• pp.312-320
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• 2011

In order to estimate a better methodological factor to understand phytoplankton ecology between abundance and bio-volume of phytoplankton, each 1,160 phytoplankton data, including abundance, classification and chlorophyll $a$ concentration were collected in Korean coastal waters of Incheon (Yellow sea), Tongyeong (South sea), and Ulsan (East sea). Based on these data, phytoplankton bio-volume can be calculated through a geometric model. The correlation coefficient between abundance and chlorophyll $a$ concentration was higher than the coefficient between biovolume and chlorophyll $a$ concentration, because a small size phytoplankton has relatively dense chlorophyll contents compared with the proportion of chlorophyll in a large size phytoplankton. Thus, the interpretation using abundance to understand phytoplankton ecology in Korean coastal waters may be more effective than that using bio-volume.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.8 no.3
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• pp.243-250
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• 2003

The spatio-temporal distribution of zooplankton community was investigated in Kyeonggi Bay with monthly samples from February 2001 to December 2001 at 5 stations along a transect between Incheon coastal waters and Seongap-Do. Monthly mean abundance of total zooplankton ranged from 1,100(Feb.)∼404,200 indiv./㎥ (Aug.) and annual mean abundance of total zooplankton was 55,000 indiv./㎥. The spatial mean abundance of total zooplankton varied from 114,600 indiv./㎥ (Incheon coastal waters) to 16,500 indiv./㎥ (Seongab-Do). Zooplankton abundance was higher in the inner bay than in the outer bay. Noctiluca scintillans, Acartia hongi, Oithona davisae, Paracalanus crassirostris, Paracalanus indicus and Oikopluera spp. were dominant species in Kyeonggi Bay and they contributed 95％ of annual mean abundance of total zooplankton. Most of dominant species distributed widely in study area throughout the year, however seasonal abundance peak only happened in inner part of the Bay. This pattern suggests that the spatio-temporal distribution of zooplankton is affected by the variations of water temperature and phytoplankton standing stock.

• Ocean and Polar Research
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• v.30 no.4
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• pp.509-518
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• 2008

Distribution of bacterial abundance and production was investigated in seawater around Saemangeum dike 7 times during March, $2007{\sim}July$, 2008. In the inner area of the dike, salinity variation was great due to river runoff from Mangyung and Dongjin Rivers and high chlorophyll a (chl a) concentrations up to $124.3{\mu}g\;l^{-1}$ was found. In the outer area of the dike, salinity was higher than in the inner area of the dike, and chl a was lower up to 10 times than in the inner area of the dike. Thus, the area of Saemangeum showed meso- to hypereutrophic conditions. Bacterial abundance and production ranged from 0.3 to $4.3{\times}10^9\;cells\;l^{-1}$ and from 5.2 to $570 pmol\;l^{-1}h^{-1}$ in outer area of the dike, respectively, while in the inner area of the dike bacterial abundance and production was 3 to 4 times higher ($0.4{\sim}12.7{\times}10^9\;cells\;l^{-1}$ and $12.3{\sim}1309\;pmol\;l^{-1}h^{-1}$, respectively) than those in the outer area. In both areas, bacterial abudance and production was highest in summer and lowest in winter. However, the variations of bacterial parameters was very large in each season. These large variations seemed to be related with the supply of organic matter. Bacterial abundance and production showed significant negative correlations with salinity in the inner area, suggesting that allochthonous organic matter input by river runoff could be an important factor in regulating the distribution of bacterial abundance and production. In addition, bacterial production also correlated positively with chl a in the inner area, suggesting that autochthonous substrate might be another regulating factor of bacterial growth in the area. These results suggest that the supply of both allochthonous organic substrates introduced by river runoff and autochthonous substrates produced by phytoplankon could be important in regulating bacterial growth and utilization of organic matter in the area. Thus, to manage water quality in the inner area of dike, it seems to be important to lower the load of both organic and inorganic nutrients from adjacent rivers.

• Journal of Korean Society on Water Environment
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• v.21 no.6
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• pp.584-594
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• 2005

The spatio-temporal abundance pattern of algae in Lake Paldang from 2002 to 2004 was investigated. The concentration of chlorophyll a representing algal biomass had fluctuated intensively throughout the year. Among three years, the highest algal biomass was shown in 2002, and typical growth peak of concentration of chlorophyll a was occurred in spring and autumn. There had been frequent rainfall in spring drought period in 2003 and it resulted in the decrease of the algal biomass. The distribution pattern of four algal groups on the surface water of Lake Paldang showed different abundance by season and by water area. In particular, different algal growth characteristics by water areas were observed. Influences of various environmental parameters on algal abundance in four water areas of Lake Paldang were analyzed statistically. From the results of Peason correlation analysis, it was understood that the kinds and affects of environmental parameters were different according to water areas and seasons. Based on the factors analysis of environmental parameters on the concentration of chlorophyll a, stepwise regression models whose independent variables were the factors produced by factor analysis and dependent variable was the concentration of chlorophyll a were derived by water areas and seasons. As a whole, factors related with organics and photosynthesis were revealed to have high affects to algal abundance, whereas limiting nutrients such as phosphorus and nitrogen showed little affect in Lake Paldang.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.44 no.6
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• pp.717-731
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• 2011

To clarify relationships between the abundance and biological characteristics of Pacific salmon Oncorhynchus spp., we analyzed spatiotemporal changes in fork length, body weight, and an index of relative abundance (catch per unit effort, CPUE) for pink salmon (O. gorbuscha), chum salmon (O. keta), and sockeye salmon (O. nerka) collected by research gill-nets from the T/V Oshoro-maru and the T/V Hokusei-maru of Hokkaido University in the North Pacific during 1953-2007. Populations of each species were distributed throughout the western Bering Sea, eastern Bering Sea (EB), western North Pacific (WNP), central North Pacific (CNP), eastern North Pacific (ENP), and Okhotsk Sea. Since 1970, the average body size of chum salmon at ocean ages 0.3-0.4 has generally declined in the WNP and CNP. However, the average body sizes of sockeye and pink salmon have not shown temporal changes. Chum salmon showed significant negative (positive) correlations between CPUE and body size for populations in CNP (ENP) at ocean ages 0.2-0.3 (age 0.1) for both sexes. In general, sockeye salmon also showed significant negative (positive) correlations between CPUE and body size for populations in the EB at ocean ages X.2-X.3 (age X.1) for both sexes, except in CNP at age 2. Our results suggest that better growth by chum and sockeye salmon in the early periods of their ocean life histories might produce higher abundance. This higher abundance, which might also be affected by overlapping distributions among Pacific salmon species and populations in certain seas, in turn appears to cause density-dependent declines in growth in the following ocean life history period due to the limited carrying capacity of the seas. To understand complex dynamics in Pacific salmon species in the North Pacific Ocean, research on interactions among species and populations is needed.

• Korean journal of applied entomology
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• v.50 no.3
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• pp.209-214
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• 2011

Changes in insect communities are one of the best indicators of environmental changes. A survey was conducted using the Flight Interception Trap (FIT) method to check the changes of species composition and abundance of silphids at Mt. Sokrisan National Park from April to October in 2003 to 2007. A total of 9,704 individuals of six silphid species were examined by FIT. Among them, Nicrophorus quadripunctatus was the most dominant species with 8,763 (90.3%) individuals. There were only 971 (9.7%) individuals of the other five species. The seasonal abundance of silphids peaked in July and August. The annual abundance has decreased gradually since 2004. Therefore, the changing patterns of species composition and abundance of silphids checked by long-term monitoring could be used as environmental indicators which indirectly show the environmental changes of Mt. Sokrisan National Park.

• Ocean and Polar Research
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• v.43 no.3
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• pp.99-111
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• 2021

Occurrence of epiphytic dinoflagellates (EPDs) in coastal waters off Jeju was first reported in 2011 based on 45 substrate samples from 24 macroalgal species. When re-analyzing, the extreme heterogeneous distribution of whole and genus-specific EPDs was reconfirmed across the sampling stations and substrate macroalgal species, as well as even across substrate samples of the same species. Abundance maximum of an EPD genus (cells g-wwt^-1) at a fixed surface-to-volume ratio (SA/V ratio) of the macroalgal species increased as the SA/V ratio increased up to 500 (cm² cm^-3). However, the abundance maximum of Ostreopsis further increased even in the MG2 (morphological group 2) macroalgae with the SA/V ratios over 500. The number of substrate macroalgal species on the plane of the MG and sampling station was more or less evenly scattered than the average EPD abundance, which was primarily driven by Gambierdiscus and Ostreopsis. Of the total EPD abundance of the five stations, 90.6% were represented by the two most common and abundant genera, Gambierdiscus and Ostreopsis, each accounting for 41.6% and 49.0%. Spatially, 95.9% of the total EPD abundance was found in St. 4 and St. 5, of which St. 4 with higher water temperature had more Ostreopsis spp. (31.8%), and St. 5 with higher salinity had more Gambierdiscus spp. (27.3%). Thus, the environmental transition to favorable T-S condition to MG2, the thin filamentous macroalgal group with very high SA/V ratios, is thus likely to support further success in EPD genera led by Ostreopsis in the coastal waters of Jeju.