• Title/Summary/Keyword: richness

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Seasonal Variation in Macroalgal Community Structure around the Byeonsan Peninsula, Korea (변산반도 해조류 군집구조의 계절적 변동)

  • Han, Su Jin;Lee, Ji Hee;Jeon, Da Vine;Oh, Ji Chul;Kim, Bo Yeon;Park, Seo Kyoung;Choi, Han Gil;Nam, Ki Wan
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.47 no.3
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    • pp.274-282
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    • 2014
  • We examined seasonal variation in the structure of marine macroalgal communities at five sites around the Byeonsan Peninsula, Korea, from January to October 2011. Sixty eight species were identified, including 11 green, 17 brown and 40 red algae. Species richness was highest at Gyeokpo (51 species) followed by Sambal (47), Gosapo (34), Byeonsan (33), and Habgoo (18). Seaweed biomass ranged from 12.98 to 145.33 g dry $wt/m^2$, with maximum and minimum biomasses at Gyeokpo and Habgoo, respectively. Sargassum thunbergii was the representative alga species occupying 47.89% of the total biomass. The dominant seaweeds were S. thunbergii, Corallina pilulifera, Ulva spp, Gracilaria vermiculophylla, and Carpopeltis affinis. No distinctive vertical distribution of seaweeds was found because S. thunbergii, Ulva spp, and G. vermiculophylla were all distributed from high to low shore. Community indices were as follows: dominance index (DI), 0.44-0.61; richness index (R), 6.27-10.35; evenness index (J'), 0.38-0.59; and diversity index (H'), 1.48-1.71. Gyeokpo had the most biomass and highest species richness, and the lowest percentage of Ulva species. However, species richness declined at Gyeokpo, from 78 to 51 species within 10 years, implying that eutrophication and sedimentation from Mankyeong and Dongjin rivers have reduced the stability of seaweed communities.

Evaluation of Habitat Function of National Park Based on Biodiversity and Habitat Value (보호지역의 지정 및 관리를 위한 국립공원의 서식처 기능 평가 -생물종다양성과 서식처 가치에 기반하여-)

  • Ryu, Ji-Eun;Choi, Yu-Young;Jeon, Seong-Woo;Sung, Hyun-Chan
    • Journal of the Korean Society of Environmental Restoration Technology
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    • v.21 no.5
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    • pp.39-60
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    • 2018
  • National parks are designated for the purpose of maintenance, conservation and utilization of different habitats. Therefore, it is necessary to select habitats of a high value as a protected area in order to balance conservation and development. However, the existing national park boundary adjustment and new designation criteria only focused on the endangered species and protected area, without proper evaluation of the habitat value of actual species. Therefore, this study aims to quantitatively evaluate habitat function in terms of biodiversity and habitat value, so that it can be referred to for the designation and boundary adjustment of national parks. We assessed species diversity and habitat values for each of the habitat types, for mammals only, as they are able to choose preferred habitats. In order to evaluate biodiversity, we used Maxent to derive species richness map and used InVEST's Habitat quality model to evaluate habitat value. As a result of evaluation, species richness was high in the national park boundary area. Also, even if the same edge is adjacent to the development area depending on the land cover, the species richness is low. Compared with Wolaksan and Sobaeksan National Park, the species richness and habitat value of the northern area, which is connected with other forests, were higher than those of the southern area where roads were developed. Therefore, it is expected that the use of the result of this study for the national park boundary adjustment and management will enhance the function of the national park as a habitat.

The Effect of Media Richness, Social Presence, and Life Satisfaction on Continuance Usage Intention or Withdrawal Intention of SNS Users via Relative Deprivation (매체 풍요도, 사회적 존재감 및 생활 만족도가 상대적 박탈감을 통해 SNS 이용자의 이용 지속 의도 또는 이탈 의도에 미치는 영향)

  • Lee, Un-Kon
    • Journal of Distribution Science
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    • v.14 no.10
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    • pp.165-178
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    • 2016
  • Purpose - This study aims to empirically verify the impact of media richness, social presence, and prior life satisfaction on various continual usage or withdrawal behaviors of SNS users via both a positive path of satisfaction and a negative path of relative deprivation. By identifying these causal paths, we observe dynamic interactions of SNS user psychology in a balanced view, and provide some implications about design principles for SNS providers. Research design, data, and methodology - We developed 16 hypothesis based on media richness theory, social presence theory, social comparison theory, the literature about relative deprivation, and the literature about the various reactions of IS users. The rich SNS media, social presence recognition among peer SNS users, and prior life satisfaction could generate positive experience, attitude, and virtuous behavioral intentions among SNS users. At the same time, rich media, low social presence, and low prior life satisfaction could generate relative deprivation and could increase withdrawal behavioral intentions such as refusal to provide information, misrepresentation of information, and removal of uploaded information in SNS. Scenario surveys were conducted to collect data from potential SNS users. Data from 357 surveys were collected and analyzed through a PLS algorithm to test the hypotheses. Results - Media richness, social presence, and prior life satisfaction could significantly increase perceived enjoyment, satisfaction, and behavioral intention of continual usage and knowledge sharing. They also could significantly decrease refusal and misrepresentation intention. Relative deprivation is significantly decreased only by prior life satisfaction. Relative deprivation could not significantly decrease satisfaction, but it could significantly increase misrepresentation and removal intention, which could be regarded as information distortion intention. Conclusions - SNS providers should focus on developing rich media and social presence support because these two variables could impact the positive experiences of SNS users. Moreover, the positive experiences could heavily influence SNS user behavior. Some management is needed to prevent relative deprivation and its consequences of misrepresentation and removal intention. SNS providers should prevent SNS users from excessive image misrepresentation and removal as this information distortion could be the source of relative deprivation.

Potential impact of climate change on plant invasion in the Republic of Korea

  • Adhikari, Pradeep;Jeon, Ja-Young;Kim, Hyun Woo;Shin, Man-Seok;Adhikari, Prabhat;Seo, Changwan
    • Journal of Ecology and Environment
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    • v.43 no.4
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    • pp.352-363
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    • 2019
  • Background: Invasive plant species are considered a major threat to biodiversity, ecosystem functioning, and human wellbeing worldwide. Climatically suitable ranges for invasive plant species are expected to expand due to future climate change. The identification of current invasions and potential range expansion of invasive plant species is required to plan for the management of these species. Here, we predicted climatically suitable habitats for 11 invasive plant species and calculated the potential species richness and their range expansions in different provinces of the Republic of Korea (ROK) under current and future climate change scenarios (RCP 4.5 and RCP 8.5) using the maximum entropy (MaxEnt) modeling approach. Results: Based on the model predictions, areas of climatically suitable habitats for 90.9% of the invasive plant species are expected to retain current ecological niches and expand to include additional climatically suitable areas under future climate change scenarios. Species richness is predicted to be relatively high in the provinces of the western and southern regions (e.g., Jeollanam, Jeollabuk, and Chungcheongnam) under current climatic conditions. However, under future climates, richness in the provinces of the northern, eastern, and southeastern regions (e.g., Seoul, Incheon, Gyeonggi, Gyeongsangnam, Degue, Busan, and Ulsan) is estimated to increase up to 292%, 390.75%, and 468.06% by 2030, 2050, and 2080, respectively, compared with the current richness. Conclusions: Our study revealed that the rates of introduction and dispersion of invasive plant species from the western and southern coasts are relatively high and are expanding across the ROK through different modes of dispersion. The negative impacts on biodiversity, ecosystem dynamics, and economy caused by invasive plant species will be high if preventive and eradication measures are not employed immediately. Thus, this study will be helpful to policymakers for the management of invasive plant species and the conservation of biodiversity.

Potential impact of climate change on the species richness of subalpine plant species in the mountain national parks of South Korea

  • Adhikari, Pradeep;Shin, Man-Seok;Jeon, Ja-Young;Kim, Hyun Woo;Hong, Seungbum;Seo, Changwan
    • Journal of Ecology and Environment
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    • v.42 no.4
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    • pp.298-307
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    • 2018
  • Background: Subalpine ecosystems at high altitudes and latitudes are particularly sensitive to climate change. In South Korea, the prediction of the species richness of subalpine plant species under future climate change is not well studied. Thus, this study aims to assess the potential impact of climate change on species richness of subalpine plant species (14 species) in the 17 mountain national parks (MNPs) of South Korea under climate change scenarios' representative concentration pathways (RCP) 4.5 and RCP 8.5 using maximum entropy (MaxEnt) and Migclim for the years 2050 and 2070. Results: Altogether, 723 species occurrence points of 14 species and six selected variables were used in modeling. The models developed for all species showed excellent performance (AUC > 0.89 and TSS > 0.70). The results predicted a significant loss of species richness in all MNPs. Under RCP 4.5, the range of reduction was predicted to be 15.38-94.02% by 2050 and 21.42-96.64% by 2070. Similarly, under RCP 8.5, it will decline 15.38-97.9% by 2050 and 23.07-100% by 2070. The reduction was relatively high in the MNPs located in the central regions (Songnisan and Gyeryongsan), eastern region (Juwangsan), and southern regions (Mudeungsan, Wolchulsan, Hallasan, and Jirisan) compared to the northern and northeastern regions (Odaesan, Seoraksan, Chiaksan, and Taebaeksan). Conclusions: This result indicates that the MNPs at low altitudes and latitudes have a large effect on the climate change in subalpine plant species. This study suggested that subalpine species are highly threatened due to climate change and that immediate actions are required to conserve subalpine species and to minimize the effect of climate change.

Effects of reforestation approaches, agroforestry and woodlot, on plant community composition, diversity and soil properties in Madhupur Sal forest, Bangladesh

  • Hasan, Mohammad Kamrul;Islam, Md. Tariqul;Akter, Rojina;Roshni, Nasima Akther
    • Journal of Ecology and Environment
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    • v.46 no.3
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    • pp.204-217
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    • 2022
  • Background: Increasing land demands for food production have led to biodiversity loss and land degradation in the Madhupur Sal forest. Reforestation activities such as agroforestry and woodlot plantation support the conservation of diversity, restoration of forest and prevention of soil erosion in degraded natural Sal forest. Knowing about these reforestation activities, this study is needed to compare the species composition, richness, and soil nutrients of these two plantation activities to the natural Sal forest in the degraded Madhupur Sal forest in Bangladesh. Results: The analysis showed that in between the reforestation activities, the highest Shannon-Wiener index (1.79), evenness (0.60) and Simpson's index (0.79) were found in the agroforestry site compared to the woodlot plantation site. On the contrary, the highest species richness (n = 14), tree basal area (19.56 m2 ha-1), Margalef's index (1.96) were recorded in woodlot plantation than in the agroforestry site. We observed that at 0-15 cm depth, soil organic matter (2.39%), total nitrogen (0.14%), available phosphorous (62.67 ㎍ g-1) and exchangeable potassium (0.36 meq/100 g) in agroforestry plots were significantly higher compared to other forest sites. At topsoil (15-30 cm depth), soil organic matter (1.67%) and available phosphorous (21.09 ㎍ g-1) were found to be higher in agroforestry site. Conclusions: Both reforestation approaches improved soil function, although woodlot plantation had the higher species richness. Therefore, plantation activities by the sustainable implementation of these two practices are the best alternative to restore the biodiversity, richness and conserve soil fertility in the Madhupur Sal forest of Bangladesh.

The Print Richness of Early Childhood Classroom (유아교실의 문식성 환경에 대한 연구)

  • Kim, Jung Wha;Lee, Moon Jung
    • Korean Journal of Child Studies
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    • v.28 no.3
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    • pp.101-113
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    • 2007
  • The present study investigated the print richness of early childhood classrooms and examined differences in classroom literacy environment by teacher demographics. The 117 participants were teachers of kindergartens and daycare centers. They responded to a 33-item questionnaire constructed by Wolfersberger et al.(2004). Questionnaire categories included literacy items pertaining to classroom environment and literacy items pertaining to teacher-student interactions. Major findings were that the classroom literacy environment was usually satisfactory. The age and career of teachers was the predictor of the classroom literacy environment, especially 'providing the classroom with literacy tools' and 'arranging literacy tools in the classroom space'.

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Effects of Experimental Drought on Soil Bacterial Community in a Larix Kaempferi Stand

  • Kim, Beomjeong;Choi, Byoungkoo
    • Journal of Forest and Environmental Science
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    • v.34 no.3
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    • pp.258-261
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    • 2018
  • Drought alters soil microorganisms; however, it is still not clear how soil microbes respond to severe drought conditions. In this study, the responses of soil bacterial community to experimental drought in a coniferous stand were examined. Six $6m{\times}6m$ plots with three replicates of control and drought treatments were delimited. PCR amplification and Illumina sequencing were conducted for cluster analysis of soil bacterial community and species richness and species diversity was analyzed. Along the 393 days of simulated drought from July 2016 to October 2017, soil bacterial species diversity slightly increased whereas species richness decreased in both control and roof plots. Moreover, soil bacterial species richness more decreased in roof plots than in controls. Combining these results, soil bacterial activity might have been altered by simulated drought.

Use of Emotion Words by Korean English Learners

  • Lee, Jin-Kyong
    • English Language & Literature Teaching
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    • v.17 no.4
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    • pp.193-206
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    • 2011
  • The purpose of the study is to examine the use of emotion vocabulary by Korean English learners. Three basic emotion fields, pleasure, anger, and fear were selected to elicit the participants' responses. L1 English speakers' data was also collected for comparison. The major results are as follows. First, English learners responded with various inappropriate verb forms like I feel~, I am~ while the majority of English native speaking teachers responded with subjunctive forms like I would feel~. In addition, L2 English learners used mostly simple and coordination sentences. Second, the lexical richness, measured through type/token ratio, was higher in English L1 data than in English L2 data. The proportion of emotion lemmas reflects the lexical richness or the diversity of the emotion words. Lastly, L2 English learners' responses focused on a few typical adjectives like happy, angry and scared. This structural and semantic distinctiveness of Korean English learners' emotion words was discussed from pedagogical perspectives.

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CORRELATION FUNCTIONS OF THE APM CLUSTERS OF GALAXIES

  • PARK CHANGBOM;LEE SUNGHO
    • Journal of The Korean Astronomical Society
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    • v.31 no.2
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    • pp.105-108
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    • 1998
  • We have found that the two-point correlation function of the APM clusters of galaxies has an amplitude much higher than that claimed by the APM group. As the richness limit increases from R = 53 to 80, the correlation length increases from 17.5 to 28.9 $h^{-1}Mpc$. This indicates that the richness dependence of the APM cluster correlation function is also much stronger than what the APM group has reported. The richness dependence can be represented by a fitting formula ro = 0.53dc + 0.01, which is consistent with the Bahcall's formula ro = 0.4dc. We have tried to find the possible reason for discrepancies. However, our estimates for the APM cluster correlation function are found to be robust against variation of the method of calculation and of sample definition.

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