• The Korean Journal of Ecology
• /
• v.17 no.3
• /
• pp.299-310
• /
• 1994

Intraspecific clonal interactions have important influences on a population structure of the cellular slime mold (CSM). This study was to investigate whether or not evolutionary change in a population could be induced by clonal competition, and to elucidate how various clones in a population evolve in a homogeneous environment of laboratory culture. The characteristic clones of Polysphondylium pallidum which had different resource consumption rates (RCR) and mating types I and II were selected for study. Investigation was conducted for 4 experimental time interval $(T_0-T_4)$; one experimental time interval took almost 10-14 days from inoculation to havest of fruiting bodies. Two sets of 50 clones were cultured from 50 clones at To, and RCR variations of the population were compared between $(T_0\;and\;T_4)$ for each set of clones. Each clone of the CSM had a diverse resource consumption rate, or growth rate, in a homogeneous and limited Cerophyl agar plate despite the passage of 48-56 generations from the beginning of the experiment. Diverse clones with different growth rate could coexist in one site of the homogeneous agar plate as well as heterogeneous soil microenvironment. When there was high clonal diversity of RCR, a clone in a population had high chances to encounter other clones with resultant increased clonal competition. In one set, 26 of 37 clones of mating type I were changed to mating type Il for the 4 experimental time intervals, which indicated that the rate of competitive exclusion among clones during total experiment from $(T_0\;to\;T_4)$ was 0.703. In another set, 31 of 37 clones of mating type I were changed to mating type II , having the rate of competitive exclusion 0.838. The frequency of each of mat~ng types changed by 0.93-1.29% in each successive generation. The competitive exclusion among clones occurred by 1.26-1.75% when approximately $2.6{\times}10^8$ bacterial cells were provided as food and thereafter one generation of myxamoebae of CSM elapsed at room temperature. This finding implicated that in the vegetative state of P, pallidurn there was 1.26-1.75% probabil~ty of evolutionary change per generation changing from one clone to another clone.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
• /
• v.19 no.1
• /
• pp.8-34
• /
• 2014

We reviewed foreign evaluation systems based on the macrobenthic and macroalgal communities and developed a system, composed of a set of ecological indices able to evaluate the functionality (FI, Functional Index; estimation of stability and productivity) and maturity (MI, Maturity Index; comparisons with biological parameters of natural reefs) of artificial reefs by comparing the status in the adjacent natural reefs in Korean coastal waters. The evaluation system was applied to natural and artificial reefs/reef-planned areas (natural reefs), established in the 5 marine ranching areas (Bangnyeong-Daechung, Yeonpyung, Taean, Seocheon and Buan) in the west coast of Korea. The FI ranged between 31.6 (Bangnyeong-Daechung) and 72.5% (Buan) and MI did between 53.1 (Seocheon) and 76.9% (Taean) in average. The evaluation of artificial reefs by the two indices, showed the most appropriate status in Taean. The FI between the adjacent artificial and natural reefs were in significant linear relationship ($r^2=0.83$, p=0.01). This indicated the local status of biological community may be critical in determining the functionality of the artificial reefs. We have suggested an integrative but preliminary evaluation system of artificial reefs in this study. The output from the evaluation system may be utilized as a tool for environment/resource managers or policy makers, responsible for effective use of funds and decision making. Given the importance, we need to use the options to enhance and improve the accuracy as follows: (1) continuous validation of the evaluation system and rescaling the criteria of indicators, (2) vigorous utilization of observation and experience through the application and data accumulation and (3) development and testing of brand-new indicators.

• Korean Journal of Environmental Biology
• /
• v.39 no.1
• /
• pp.100-107
• /
• 2021

Along with an increase in the frequency of high-concentration fine particulate matter in Korea, interest and research on ammonia (NH₃) are actively increasing. It is obvious that agriculture has contributed significantly to NH₃ emissions. However, studies on the long-term effect of fertilizer use on the ambient NH₃ concentration of agricultural land are insufficient. Therefore, in this study, NH₃ concentration in the atmosphere of agricultural land was monitored for 11 months using a passive sampler. The average ambient NH₃ concentration during the total study period was 2.02 ㎍ m^-3 and it was found that the effect of fertilizer application on the ambient NH₃ concentration was greatest in the month immediately following fertilizer application (highest ambient NH₃ concentration as 11.36㎍ m^-3). After that, it was expected that the NH₃ volatilization was promoted by increases in summer temperature and the concentration in the atmosphere was expected to increase. However, high NH₃ concentrations in the atmosphere were not observed due to strong rainfall that lasted for a long period. After that, the ambient NH₃ concentration gradually decreased through autumn and winter. In summary, when studying the contribution of fertilizer to the rate of domestic NH₃ emissions, it is necessary to look intensively for at least one month immediately after fertilizer application, and weather information such as precipitation and no-rain days should be considered in the field study.

• Korean Journal of Environmental Biology
• /
• v.33 no.1
• /
• pp.75-82
• /
• 2015

To overcome the stream fragmentation and blockage of migration of fishes by dams and weirs, fishways are commonly installed. However, limited studies were conducted for effectiveness and suitability of fishways installed in Korean streams. In this study, we investigated fish usages (by time periods, locations and months) of the Ice Harbor type fishway installed in the Gongju weir using traps. The monitoring were monthly conducted from June to October, 2012. The number of individuals which used fishway in September and October decreased than in June to August. Although no statistical significance was identified, many numbers of species and individuals were occurred at the trap installed at the left end of fishway than others. Fishes of more diverse size classes occurred at this trap as well. The number of collected individuals and water level of weir were positively correlated though they showed low correlation coefficient. Conversely, occurrence rate of fishes smaller than 70 mm of total length decreased with increasing water level of weir. fishway usage time of fish were different depends on ecological characteristics of each species. Various sizes of fishes can use fishway for their upstream migration. These results are useful for establishing management and evaluation plans of Ice Harbor type fishway in S. Korea.

• Korean Journal of Plant Resources
• /
• v.33 no.5
• /
• pp.482-500
• /
• 2020

The purpose of this study was to identify the phytosociological vegetation structure through a sampling survey of Mt. Jirisan National Park. And it was conducted to provide the latest data for establishing a conservation and management plan for forest ecosystems. As a result of TWINSPAN classification, it was classified into 4 communities. Group I is the Fraxinus mandshurica - Acer pseudosieboldianum Community, group II is the Quercus serrata - Quercus variabilis Community, group III is the Quercus mongolica Community, group IV is the Pinus densiflora Community. Group I is dominated by Fraxinus mandshurica in the canopy layer, and Cornus controversa and Quercus mongolica compete and maintain dominance. Group II is dominated by Quercus variabilis and Quercus serrata in canopy layer, and Styrax obassia and Styrax japonicus compete in sub-tree layer. In group III, Quercus mongolica has a high dominance of 67% in canopy layer and 27% in the sub-tree layer, and Acer pseudosieboldianum competes with the Quercus mongolica in the sub-tree layer. In group IV, Pinus densiflora showed a high dominance of 74% in canopy layer. The sub-tree layer is dominated by Quercus mongolica, and is accompanied by competition between Carpinus tschonoskii and Fraxinus sieboldiana.

• Journal of Korea Foresty Energy
• /
• v.24 no.1
• /
• pp.13-27
• /
• 2005

In order to design new fertilizers for forests, seedlings of Pinus densiflora, Larix leptolepis Betula platyphylla var. japonica, and FQuercus acutissima were treated with different fertilizers, and nutrient concentrations in seedling components were analyzed. In general, nitrogen (N) and phosphorus (P) concentrations in seedling components increased after N and P application. Potassium (K) concentration in seedling components of Pinus densiflora and Quercus acutissima increased after N, P and K application. However, there were no significant changes in calcium (Ca), sodium (Na) and magnesium (Mg) concentrations. Nitrogen and P concentrations in seedling components increased with the amount of solid combination fertilizer and UF combination fertilizer. Potassium concentration for Pinus densiflora and Na and Ca concentrations for Larix leptolepis also increased with the amount of combination fertilizers. However, nutrient concentrations in seedling components showed no significant changes with different combination fertilizers.

• Journal of Ecology and Environment
• /
• v.35 no.2
• /
• pp.123-129
• /
• 2012

Salt marsh is an important transitional zone among terrestrial, riverine, and marine ecosystems and is a productive habitat that interacts extensively with adjacent landscape elements of estuarine and coastal ecosystems. Nowadays, in addition to various human activities, a variety of natural processes induce changes in salt marshes. This study aims to provide background information to restore disturbed salt marshes and to propose their ecological restoration using seed banks. The study area is a prepared area for the Gwangyang Container Port located in the southern Korea. This area was formed by accumulating mud soils dredged from the bottom of the forward sea. This land was created in a serial process of preparing the Gwangyang container port and the salt marsh was passively restored by seeds buried in mud soil dredged from seabed. As a result of stand ordination based on vegetation data collected from the land, stands were arranged according to tolerance to salinity in the order of $Suaeda$ $maritima$, $Salicornia$ $europaea$, and $Phragmites$ $communis$ communities on the Axis 1. Landscape structure of the projected area was analyzed as well. Edges of the projected area were divided from the marginal waterway by the dike. Four types of vegetation appeared on the dike: $Alnus$ $firma$ plantation, $Robinia$ $pseudoacacia$ plantation, $Lespedeza$ $cyrtobotrya$ plantation, and grassland. In the more internal areas, two types of vegetation sequences appeared: $Aster$ $tripolium$ community-$Suaeda$ $glauca$ community-$Salicornia$ $europaea$ community sequence and $Aster$ $tripolium$ community-$Suaeda$ $maritima$ community-$S.$ $europaea$ community sequence. Mixed community showed the highest species diversity (H' = 0.86) and $S.$ $europaea$ community showed the lowest (H' = 0.0). Evenness is the highest in Mixed community (J' = 2.26) and the lowest in $S.$ $maritime-S.$ $europaea$ community (J' = 0.0). Several plant communities were successfully established on the land created by mud soil dredged from the bottom of Gwangyang Bay. Moreover, community diversity in this area approached a similar level with those from other studies involving natural salt marshes. Therefore, restoration effect based on community diversity obtained in our study can be evaluated as a successful achievement. In this respect, although most salt marshes in Korea and other places worldwide have been destroyed or disturbed by excessive land use, feasibility of seed bank as a restoration tool is greatly expected.

• Journal of Environmental Science International
• /
• v.24 no.11
• /
• pp.1405-1415
• /
• 2015

This study is conducted to determine the damage, distinguish the types and identify the restoration by that type for 13 Korea national parks out of 21. There are 21 Korea national parks are in Korea covering 6.67% of the country or $6,656km^2$ ($3,902km^2$ on land and $2,754km^2$ in the sea) currently since the area around Jirisan ($440km^2$) was designated as the first Korea national parks in 1967. With the cancellation of entrance admission on Korea national parks since 2007, annual visitors to the Korea national parks have grown from 37 millions in 2008 to 46 millions by 2013 and continue to grow due to numerous leisure activities, alpine activities and social changes. As such, Korea national parks are natural resource with high value to be conserved and are attracting significant attention as recreational spaces for people at the same time. On the other hand, there have been issues of soil erosions or disturbed vegetation due to increased number of visitor to the national parks. Korea national parks area damage to its type and damage characteristics to analyse the 13 Korea national parks out of 21 on July 2012 March, Korea national parks over the subjects of the National Park from damaged area status Survey analysis by the Korea National Park Service. As a result, 203 million units in the 16 Korea national parks damaged land of the reform package during ecological trail (including non-regular hiking trails) 153 (77.66%), damaged valleys 20(9.14%) independent damaged area, 13 disconnected ecological axis(7.61%), closed trail(2.03%) (3.55%), and line type damage(like a non-regular hiking trails) appears to be a high ratio. Korea national parks damaged land of the results identified, by contrast ratio and the annual number of visitors Bukhansan national park(49.26%), Gyeongju national park(23.65%) damaged land rates, such as Seorasan national park(4.93%), Songnisan national park (4.43 %), Gyeryongsan national park(3.45%), and the annual number of visitors be similar result. The National Park Service has been reporting on damages and restorations but damages and their types have not been established yet. Damages have been generally studied and categorized on hiking trails due caused by heavy traffic on them but the reports were limited on hiking trails only. Since damage to the Korea national parks are not limited on the hiking trails, it is necessary to determine damages in various aspects. Thus, in this study, damage types, spatial characteristics, causes and restorations are analyzed based on the survey results of damages to national parks in order to provide a basis for the efficient management and operation of the Korea national parks.

• Korean Journal of Environment and Ecology
• /
• v.27 no.6
• /
• pp.666-675
• /
• 2013

This research was carried out from March 2009 to July 2012 to explicate the height change based breeding-ecological characteristics of Titmice that were breeding in the artificial nests installed in the Halla Mountain. The first egg-laying day was delayed as the height of the area under investigation increased, and it turned out that the decrease in temperature due to the elevated height had influence on that delay (p<0.05). Generalizing the annual results of the analyses, we see that there was no significant correlation occurring between the average temperatures and egg-laying days in the breeding season (April~June) (p>0.05). The rate of artificial nest use was not different among areas and among year, but between the species, Parus major and Parus varius. There were differences in clutch sizes among species (p>0.05), but no differences in heights and years (p<0.05). The hatching-, fledging-, and breeding-success rates were 67.3%, 99.5%, and 67.0% respectively in 2011, and 71.3%, 96.8%, 69.0% respectively in 2012, from which we can tell that the fledging-success rate was high but the hatching- and breeding-success rates were similar. Though we confirm that temperature changes due to height differences had influence on breeding periods, but we cannot identify a significant correlation with other breeding-ecological characteristics. Thus, in order to more precisely explicate the influence of temperature changes due to heights on Titmice's breeding, long-term research is needed in terms of the investigation of microclimatic factors and food resource.

• Journal of Korea Foresty Energy
• /
• v.23 no.2
• /
• pp.9-20
• /
• 2004

Growth and nutrients of Xinjiang poplar (Populus alba var. pyramidalis) seedlings treated with fertilizers and soil amendments were examined in nursery and windbreak at Dengkou after 6 months of treatments in Inner Mongolia, China. Soil water content was $10\%$ higher than that at most soils in desert. Height and diameter growth and foliar nitrogen (N) concentration were higher at N and nitrogen plus phosphorus (N+P) fertilizer treatments than other treatments. However, there were no differences in foliar P concentration among treatments in windbreak and foliar P concentration was higher at control than at other treatments in nursery. Yuho treatment increased height and diameter growth. Nitrogen appeared an influenciug factor for early growth of Xinjiang poplar, and P had a minor affect on growth. More long-time studies were needed to elucidate the effects of fertilizers and soil amendments on growth and nutrients of Xinjiang poplar.