• The Korean Journal of Ecology
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• v.16 no.4
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• pp.477-487
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• 1993

To investigate phenological differences among species, and relationship between phenology and air temperatures, we surveyed foliation and flowering times of several woody plants in two temperate forests, Namhansansung and Taegwallyong area, for three years, 1991, 1992 and 1993. In Namhansansung area, the leaves of Quercus mor~golica, Rhododendron mucronulatum, Prunus levezlleana and Symplocos chinensis for. pilosa expanded in the early season(about 10 April), and those of Quercus variabilis, Quercus dentata and Maackia amurensis in the late season(about 5 May). The foliation time of the earliest species(Rhododendron mucronulatum) was 27 days earlier than thzt of the latest(Maackia amurensis, Quercus variabilis and Quercus dentata). In Taegwallyong area, the leaves of Staphylea bumalda and Rhamnus yoshinoi foliated on 25 April and those of Rhus verniciflua and Fraxinus rhynchophylla on 25 May. The annual mean air temperature of Narnhansansung area was $5.5^{\circ}C$ higher than that of Taegwallyong area. Foliation times of the same species were earlier in the former: the differences between two areas were 8~24 day among species. In contrast, flowering times of the same species were 0~22 days earlier in the former. It is concluded that the budding time of leaves was related to year day index(YDI), and foliation time of leaves was related to Nuttonson's index(Tn).

• The Korean Journal of Ecology
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• v.20 no.3
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• pp.163-168
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• 1997

Taxa of the herbivorus insect larvae and their foodplant species were surveyed in a temperate forest of Namhansansung Area, Sungnam City, Kyonggi Province, in 1994-1996 growing season, Sixty two taxa of insect larvae fed on leaves of 18 woody species in 11 families during three growing season. Larvae began to be detected from the mid-April when the leafing time began. The number of larvae taxa reached to the maximum value(32 taxa) early in May, 1994. It was the time that the value of specific leaf area reached to the maximum. It decreased up to 3-4 taxa in the mid-June. Taxa of insect larvae were different year by year even in the same season. Most of larvae fed on various plant species, suggesting that they were generalist or polyphagous species. Fagaceae, Betulaceae, Ulmaceae, Rosaceae. Aceraceae, Ericaceae, Oleaceae and Styracaceae were fed on by many taxa of insect larvae, while Euonymus spp. (Celastraceae). Lindera obtusiloba(Lauraceae) and Symplocos chinensis for. pilosa(Symplocaceae) were mainly fed on by a few taxon.. Erannis, Calospilos and Phigalia were observed to feed on various species, but Illiberis, Pryeria and Chalocosia fed on only Rosaceae, Euonymus spp.(Cerastraceae) and Symplocos chinensis for. pilosa(Symplocaceae), respectively. An unidentified larva was observed only on Lindera obtusiloba (Lauraceae).

• Weed & Turfgrass Science
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• v.4 no.4
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• pp.338-347
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• 2015

Reinforcement cells are used to aid grass growth and taken together, this serves to extend greenery beyond the conventional spaces of lawns, tree pits, gardens, and parks, and is advantageous to urban cities since space for greening is often limited. Drought has variable effects on plant life and the resilience of turf to drought resistance also varies with species. Changes in photosynthetic ability were more pronounced for media rather than grass species. The media of sand without organic matter was found to be least suited for drought resistance. Normalized difference vegetation index (NDVI) and digital image analysis (DIA) data were generally in favour of Zoysia species as oppose to A. compressus. In A. compressus, selective traits such as, a more extensive root system and lower specific leaf area (SLA) were not an underlying factor that assisted this grass with enhanced drought resistance. Generally, WUE was found to be strongly related to plant characterises such as overall biomass, photosynthetic features as well as the lushness indexes, and specific leaf area. This study found a strong relationship between WUE and a suite of plant characteristics. These traits should serve as useful selection criteria for species with the ability to resist water stress.

• The Korean Journal of Ecology
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• v.27 no.2
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• pp.79-86
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• 2004

An extensive study of the vegetation characteristics of the Hamersley Ranges, a mountainous desert area of north-west Australia, facilitated the comparison of plant species diversity measures with mountainous deserts of other parts of the world. Alpha diversity was defined as the number of species co-existing at local scales and was found to average 18 species per 0.1 ha for the Hamersley Ranges. This was found to be similar to seven other mountainous deserts in North and South America, and southern Africa. Variation in alpha diversity between these deserts was found to considerably lower than within deserts, suggesting that local processes control species richness at local scales. Beta diversity, defined here as turnover in species composition at various spatial scales, can be measured in many ways. For the Hamersley Ranges, Wilson's β ranged from 1.2 to 1.6 for five sites along a topographic gradient, whereas Whittaker's β between different plant communities was found to average 0.93. Comparable data was not found for other desert areas, but comparisons to non-desert areas suggest beta diversity within landscapes is relatively high and is likely to reflect the considerable landform heterogeneity of the Hamersley Ranges. 55∼70% of species were shared between different landscapes of the Hamersley Ranges; comparisons to other regions suggest beta diversity at this scale is relatively low. Gamma diversity, the number of species over large spatial extents, was successfully compared using regression analysis of the log-log species - area relationship. This revealed that the northern Sonoran desert has significantly less species than the Nama (inland) Karoo and Hamersley Ranges over medium spatial extents, but species numbers were similar at a regional scale. Several constraints to the valid comparison of species diversity were identified, including lack of standardisation of sampling techniques, the wide range of measures employed, general lack of published data, and the influence of the various components of spatial scale on most diversity measures. Recommendations on how to improve future comparative work are provided.

• Journal of the Korean Institute of Landscape Architecture
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• v.31 no.2
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• pp.94-101
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• 2003

The purpose of this paper is to analyze the correlation between Death Rate of Trees (DRT) and the Physiological Characteristics of Trees(PCT) in POSCO Gwangyang works, which is a reclaimed area. To analyze the DRT, 15 species of deciduous trees were selected, for example Ulmus davidiana var., Zelkova serrata, Melia azedarach var. etc. Though there were numerous factors to affect the growing of trees, 5 PCT were considered to be main factors, soil salt tolerance, wind salt tolerance, water needs, transplanting difficulty, and nutrient needs. According to two kinds of soil-base: mound and pot area, we tested the relationship between 5 PCT and DRT by use of t-test and multiple regression analysis. The results are as follows. 1. The DRT of Acer palmatum, Cornus kousa, Magnolia kobus, Liriodendron tulipifera, and Albizzia julibrissin were high by more than 20%. On the other hand, Chionanthus retusa, Ulmus davidiana var. japonica Celtis sinensis, and Lagerstroemia indica were low by less than 10% in the DRT and are considered to be species suitable for planting in reclaimed areas. 2. The DRT of trees in pot areas was meaningfully higher than in mound areas; for this reason the mound technique is desirable as a soil-base for planting in reclaimed areas. 3. In the pot area, the independent variables, in the order of soil salt tolerance, wind salt tolerance, transplanting difficulty, had an effect on the DRT more significantly than in mount area. On the other hand, wind salt tolerance and soil salt tolerance affected the DRT in mount areas. This means that soil salt tolerance, wind salt tolerance, and transplanting difficulty have to be considered as significant factors to the DRT. Although the researchers tried to interpret how the PCT affected the DRT in order to analyze the relationship between the two in reclaimed areas, it was neglected at an experimental level. Therefore, future research should work on this aspect in detail.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.9 no.1
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• pp.20-29
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• 2004

Macrobenthos species-area relationship was investigated and empirical models were estimated to enable comparisons among species numbers of different sample size. The study aims to choose a way to predict cumulative relative species number (CRSN) in a given sample size Saemangeum, located in the west coast of South Korea, were visited in Apr., May and Aug.,2002 and a total of 261 biological samples from 87 stations were obtained by employing a quantitative sediment sampler, Smith-McIntyre grab and design of 3 replicates at each station. Relative species numbers (%) were baselined at sample size of 1000 $\textrm{cm}^2$ and the patterns of CRSN along the axis of sample size were measured and observed. In correlation analysis performed on a set of abiotic and biotic variables, log-transformed CRSN showed the only significant relationship with log-transformed density. Based on the result, three models, Log CRSN 2000, Log CRSN 3000 and Log CRSN were produced. The former two were devised to predict CRSN at 2000 and 3000 $\textrm{cm}^2$ respectively, and the latter at various sample sizes and samplers (all p-values were <0.001). Database from other studies (intertidal or subtidal macrofaunal samples from Kyonggi Bay and Saemangeum) were used to evaluate validity of the models. Observed CRSN below sample size of 3000 $\textrm{cm}^2$ fell under the range of 95% prediction interval and this was appeared to provide reliability of the models below that sample size.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.7 no.2
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• pp.62-67
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• 2004

Forest community structure analysis in the Seooreung area, Goyang-si was carried out to supply basic data for reasonable management and conservation. The forest vegetation of the Seooreung area was classified into Alnus japonica community, Quercus mongolica - Carpinus laxiflora community, Quercus serrata community, and Pinus densiflora community. The dominant species in the area were in the order of Quercus mongolica, Quercus serrata, Robinia pseudoacacia, Quercus variabilis, Quercus aliena, Styrax japonica, Pinus rigida, and Alnus hirsuta. According to the DBH analysis result, Pinus densiflora was dominance species in Tomb area. Pinus rigida had a density of normal distribution style in the entire forests, therefore, their dominance are expected to continue for now. However, Quercus serrata is expected to extend their influence in the future in competition with Pinus rigida. Quercus mongolica had a density of normal distribution style in the Quercus mongolica - Carpinus laxiflora community, therefore, their dominance are expected to continue for now. Carpinus laxiflora is expected to extend their influence in the future in competition with Quercus mongolica. The relationship between the distribution of dominant species of forest vegetation and soil condition in Seooreung area was investigated by analyzing soil nutrition and moisture gradient. Alnus hirsuta community was distributed in the mesic and medium nutrition area and Quercus mongolica - Carpinus laxiflora community in the serix and relative good nutrition area. Pinus densiflora community was distributed in the serix and poor nutrition area and Quercus serrata community in the subserix and medium nutrition area.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.37 no.5
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• pp.423-432
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• 2004

In coastal area of Inchon, dredging and the disposal of dredged material for sea-wall construction and reclamation have increased in recent years. These activities may impact the benthic environment and result in changes in benthic communities, but little information is available on the extent and direction of these changes. We investigated whether there have been changes in the dominant macrobenthic species and benthic community over the last decade, and explored the relationship between environmental variables and spatial patterns of macrobenthic community structure. We sampled macrobenthos and recorded environmental variables in the coastal habitats of Inchon in March and June 2004. In total, 212 macrobenthic species were recorded during this study, predominately crustaceans $(34{\%})$, mollusks $(32{\%})$ and polychaetes $(21{\%})$. The mean density of macrobenthos was $1,393\;ind./m^{2}$.The most abundant species was Amphioplus japonicus $(20.5{\%})$, followed by Heteromastus filiformis $(14.4{\%})$, Theora fragilis $(8.2{\%})$ and Ampharete sp. $(4.0{\%})$. Over the past decade the dominant macrobenthic species in this area shifted. Multivariate analysis (multidimensional scaling) revealed significant differences in community structure among three regions: the middle part of the sampling area (B), site 8 (C) and other sites (A). Mean density varied significantly among the three regions, but no differences in the number of species and diversity (H') were observed. The distribution of the macrobenthic community was affected by environmental variables such as percentage sand content and sediment kurtosis. Species that were important in different areas included A. japonicus in region A, Raeta puchella in region B and T. fragilis in region C. The important species in regions B and C were filter-feeding bivalves, and the abundance of these species may be related to the increase in percentage sand content. We suggest that the sediment composition (percentage sand content) may be an important factor in determining the dominant species and structure of the macrobenthic communities in coastal Inchon. Long-term monitoring programs are necessary to understand ongoing changes in the benthic communities of this area.

• Fisheries and Aquatic Sciences
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• v.21 no.3
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• pp.12.1-12.15
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• 2018

A preliminary investigation of length-weight relationship, condition factor and reproductive ecology of African pike fish, Hepsetus odoe, was conducted between June to August 2010 in Lake Eleiyele. A total of 90 samples of the fish species were caught by fishermen using gill nets. The results obtained showed that fish species had isometric growth pattern (contrary to negative allometry expected) with the growth exponent, b value of 2.64, that is not statistically different from 3 and with high statistical power of 0.866 when tested. The mean condition factor, K, was found to be 2.6, indicating that the fish species were in good condition in the study area. For reproductive biology, mean fecundity and gonadosomatic index were found to be 1349 eggs and 3.53% respectively. This study was necessary to fill the knowledge gap and provide information for management and conservation of the investigated species in the lake system. This study recommended that further research needs to be conducted because the sampling was carried out in the rainy season period and within a quarter of a year.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.67 no.4
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• pp.285-295
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• 2022

The trapping efficacy of five commercially available sex pheromones manufactured in Korea, the Netherlands, North America, China, and Costa Rica was evaluated to determine the population dynamics of Spodoptera frugiperda and Mythimna loreyi and their relationships with the weather parameters of maize fields in Miryang, Gyeongnam Province, Korea in 2019. The results show that the sex pheromone manufactured in Costa Rica were more efficient at capturing S. frugiperda and M. loreyi than those manufactured in other countries. The lowest number of S. frugiperda moths were captured using sex pheromones manufactured in the Netherlands. We noted that more than four population peaks of both the moth species and weather parameters influenced the moth population dynamics in Miryang. A positive relationship was observed between the population of S. frugiperda and weather parameters, such as mean temperature, rainfall, and relative humidity, for sex pheromones manufactured in Korea. Furthermore, a positive relationship was recorded between the population of M. loreyi and wind speed for the sex pheromone manufactured in Korea. The results of this study suggest that the sex pheromones manufactured in Costa Rica are the best solution for the efficient capture of S. frugiperda and M. loreyi under typical weather conditions in the southern parts of Korea. In addition, the outcomes of this study are discussed in terms of population dynamics and integrated pest management for S. frugiperda and M. loreyi as alternatives to chemical management by maize producers. Further studies related to the continuous improvement in the capture efficiency of both moth species using sex pheromones are now needed.