• 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.

• Ocean Science Journal
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• v.43 no.3
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• pp.135-146
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• 2008

The monthly distribution of zooplankton communities in Han River estuary was investigated at two stations from July 1998 to June 1999. Monthly mean abundance of total zooplankton varied remarkably, with the range from 20 $indiv.{\cdot}m^{-3}$ to 19,600 $indiv.{\cdot}m^{-3}$. During the study period, dominant species of zooplankton community were dinoflagellate Noctiluca scintillans, copepods Paracalanus indicus, Paracaanus crassirostris, Acartia hongi, Acartia ohtsukai, and meroplanton cirriped larvae. According to tidal states, relative high abundance occurred at high tide without regard to season. The temporal distribution of abundance implied that the reduced salinity probably limited the zooplankton populations and the fluctuations of salinity were an important factor in the variation of abundance. However, the results of salinity tolerance test shows that the variations in salinity do not directly influence the decrease of abundance. This study shows that the relatively high abundance of zooplankton near high tide seems to be related with the expansion of abundant zooplankton inhabiting Incheon coastal waters through tidal currents.

• Korean Journal of Ecology and Environment
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• v.56 no.2
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• pp.172-186
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• 2023

Small ponds, which exhibit unstable succession pattern of plankton community, are less well studied than large lakes. Recently, the importance of small ponds for local biodiversity conservation has highlighted the necessity of understanding the dynamics of biological community. In the present study, we collected zooplankton from three small reservoirs with monthly basis and analyzed their seasonal dynamics. To understand the complicated zooplankton community dynamics of small reservoirs, we categorized zooplankton species into four groups (LALF Group, Low Abundance Low Frequency; LAHF Group, Low Abundance High Frequency; HALF Group, High Abundance Low Frequency; HAHF Group, High Abundance High Frequency) based on their occurrence pattern (abundance and frequency). We compared the seasonal pattern of each group, and estimated community diversity based on temporal beta diversity contribution of each group. The result revealed that there is a relationship between groups with the same abundance but different occurrence frequencies, and copepod nauplii are common important component for both abundance and frequency. On the other hand, species included with LALF Group throughout the study period are key in terms of monthly succession and diversity. LALF Group includes Anuraeopsis fissa, Hexarthra mira and Lecane luna. However, groups containing species that only occur at certain times of the year and dominate the waterbody, HALF Group, hindered to temporal diversity. The results of this study suggest that the species-specific occurrence pattern is one key trait of species determining its contribution to total annual biodiversity of given community.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.8 no.1
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• pp.14-28
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• 2003

The macrobenthic faunal community of Gwangyang Bay comprised 154 species and showed the overall mean density of 1,286 individuals/$m^2$. Polychaetes were the most important component of the macrofaunal community in species richness, abundance and biomass. The dominant species in abundance were poly-chaetes like Tharyx sp.(44.8%), Lumbrineris longifolia(14.0%), Heteromastus filiformis(3.6%), a mussel Mytilus edulis, and an amphipod crustacean Corophium sinense. The abundance and biomass in the western part of the bay were lower than in the channel regions and mouth of the bay. The community indices showed the same trend in the spatial distribution with the abundance and species richness. The study area can be divided into seven station groups； five station groups in the eastern part, two groups in the channel and open mouth part of the bay.

• 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.

• 한국해양학회지
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• v.25 no.4
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• pp.189-204
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• 1990

In the KODOS (Korea Deep Ocean Study)-89 area, western part of clarion-Clipperton fracture zones in the northeastern equatorial Pacific, magnate nodules and sediments were sampled during the 'Farnella' cruise in Oct., 1989. Bulk chemical and mineralogical analyses have been made on a suit of ferromanganese nodules and sediments to study the origin and distribution pattern of the nodules. The nodules are classified into three groups based on their origin: diagenetic nodules with high Mn/Fe ratio, Cu, Ni, Zn, Mg, todorokite contents and rough surface texture; hydrogenetic nodules with high Fe, Co, vernadite contents and smooth surface texture; and transitional nodules with intermediate characters between diagenetic and hydrogenetic nodules. Study area is divided into four zones according to the origin and abundance of nodules: far north area where nodules are hydrogenetic and intermediate in abundance; north area where nodules are diagenetic and low in abundance; south area where nodules are diagenetic and intermediate in abundance; seamount area where nodules are hydrogenetic and high in abundance. distribution pattern of manganese nodules in the KODOS-89 area seems to be controlled by latitudinal variation of productivity in water column and sea bottom morphology.

• Korean Journal of Environmental Biology
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• v.24 no.1 s.61
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• pp.67-80
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• 2006

The effect of environmental forcing on picophytoplankton distribution pattern was investigated in the tropical and subtropical western Pacific (TSWP) and the East Sea in September, 2002, and the continental shelf of the East China Sea (C-ECS) in August, 2003. The abundance of picophytoplankton populations, Synechococcus, Prochlorococcus and picoeukaryotes were determined by flow cytometry analyses. Picophytoplankton vertical profiles and integrated abundance $(0\sim100\;m)$ were compared with these three physiochemically different regions. Variation patterns of integrated cell abundance of Synechococcus and Prochlorococcus in these three regions showed contrasting results. Synechococcus showed average abundance of $84.5X10^{10}\;cells\;m^{-2}$, in the TSWP, $305.6X10^{10}\;cells\;m^{-2}$ in the C-ECS, and $125.4X10^{10}\;cells\; m^{-2}$ in the East Sea where increasing cell concentrations were observed in the region with abundant nutrient. On the other hand, Prochlorococcus showed average abundance of $504.5X10^{10}\;cells\;m^{-2}$ in the TSWP, $33.2x10^{10}\;cells\;m^{-2}$ in the C-ECS, and $130.2X10^{10}\;cells\;m^{-2}$ in the East Sea exhibiting a distinctive pattern of increasing cell abundance in oligotrophic warm water. Although picoeukaryotes showed a similar pattern to Synechococcus, the abundance was 1/10 of Synechococcus. Synechococcus and picoeukaryotes showed ubiquitous distribution whereas Prochlorococcus generally did not appear in the C-ECS and the East Sea with low salinity environment. The average depth profiles for Synechococcus and Prochlorococcus displayed uniform abundance in the surface mixed layer with a rapid decrease below the surface mixed layer. for Prochlorococcus, a similar rapid decreasing trend was not observed below the surface mixed layer of the TSWP, but Prochlorococcus continued to show high cell abundance even down to 100 m depth. Picoeukaryotes showed uniform abundance along $0\sim100\;m$ depth in the C-ECS, and abundance maximum layer appeared in the East Sea at $20\sim30\;m$ depth.

• The Korean Journal of Ecology
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• v.11 no.1
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• pp.1-15
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• 1988

Studies on species compostion, promary production of benthic algal assemblage were carried out along a channel of the salt marsh near Inch'on, Kyonggi Bay, Korea. Possible biological, physical and KDICical factors controlling the aglal assemblage were also examined. The oveall diatoms were encountered one hundred and thirty-seven taxa, of which the dominant species were Paralia sulcata and Cymatosira belgica. These two species accounted for 32.6% relative abundance throughout the study period. Diatom taxa had no clear seasonal pattern in abundance analysis. But at the algal blooming period in spring, euglenoids occurred with a high abundance. The chlorophyll a content of benthic algae showed definite seasonal pattern. The algal biomass of the appeared to influence the spatial fluctuation in the algal biomass of the channel was regulated primarily by water content of sediment. Grazing by zoobenthos apperaed to influence the spatial fluctuation in the algal biomass of the sediment surface. The algal photosynthesis was measured in the laboratory with oxygen method. Photo-synthetic rate was independent of the temperature under the lower irradiance. The gross production from March to November was estimated to be 190g C/m2 at the channel slope. Photosynthetic efficiency was 0.37% on the basis of the photosyntherically active radiation for the study period.

• Korean Journal of Environmental Biology
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• v.30 no.1
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• pp.64-70
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• 2012

This study compares the abundance and community structure of zooplankton organisms from the littoral and pelagic regions, and considers particularly trophic levels vs. zooplankton abundances. Zooplankton samples, collected every 3 months over a year from 2010 to 2011 at 29 temperate lakes and reservoirs, which belong to two different river basins (Youngsan and Seomjin River). The spatial pattern of rotifers was similar to that of total zooplankton abundance. This reflected the fact that rotifers strongly dominated the zooplankton community. There were considerable spatial variations in total zooplankton abundance (ANOVA, p<0.01), while there were no significant differences both in littoral and pelagic regions in abundance of zooplankton (ANOVA, p=0.205). The mean abundance of zooplankton in eutrophic systems was much higher than that of mesotrophic systems, while significant difference in number of species and diversity index were not shown in both trophic systems.

• Ocean Science Journal
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• v.40 no.3
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• pp.109-117
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• 2005

Daily changes in phytoplankton abundance and species composition were monitored from July to September 2003 (n=47) to understand which factors control the abundance at a station in Jangmok Bay. During the study, the phytoplankton community was mainly composed of small cell diatoms and dinoflagellates, and the dominant genera were Chaetoceros, Nitzschia, Skeletonema and Thalassionema. Phytoplankton abundance varied significantly from $6.40{\times}10^4$ to $1.22{\times}10^7$ cells/l. The initially high level of phytoplankton abundance was dominated by diatoms, but replacement by dinoflagellates started when the NIP ratio decreased to <5.0. On the basis of the N/P and Si/N ratios, the sampling periofd could be divided into two: an inorganic silicate limitation period (ISLP, $14^{th}$ $July-12^{th}$ of August) and an inorganic nitrogen limitation period (INLP, $13^{th}$ of August - the end of the study). Phosphate might not limit the growth of phytoplankton assemblages in the bay during the study period. This study suggests that phytoplankton abundance and species composition might be affected by the concentrations of inorganic nutrients (N and Si), and provides baseline information for further studies on plankton dynamics in Jangmok Bay.