• 제목/요약/키워드: Rare sub-community

검색결과 6건 처리시간 0.019초

Responses of Soil Rare and Abundant Sub-Communities and Physicochemical Properties after Application of Different Chinese Herb Residue Soil Amendments

  • Chang, Fan;Jia, Fengan;Guan, Min;Jia, Qingan;Sun, Yan;Li, Zhi
    • Journal of Microbiology and Biotechnology
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    • 제32권5호
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    • pp.564-574
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    • 2022
  • Microbial diversity in the soil is responsive to changes in soil composition. However, the impact of soil amendments on the diversity and structure of rare and abundant sub-communities in agricultural systems is poorly understood. We investigated the effects of different Chinese herb residue (CHR) soil amendments and cropping systems on bacterial rare and abundant sub-communities. Our results showed that the bacterial diversity and structure of these sub-communities in soil had a specific distribution under the application of different soil amendments. The CHR soil amendments with high nitrogen and organic matter additives significantly increased the relative abundance and stability of rare taxa, which increased the structural and functional redundancy of soil bacterial communities. Rare and abundant sub-communities also showed different preferences in terms of bacterial community composition, as the former was enriched with Bacteroidetes while the latter had more Alphaproteobacteria and Betaproteobacteria. All applications of soil amendments significantly improved soil quality of newly created farmlands in whole maize cropping system. Rare sub-communitiy genera Niastella and Ohtaekwangia were enriched during the maize cropping process, and Nitrososphaera was enriched under the application of simple amendment group soil. Thus, Chinese medicine residue soil amendments with appropriate additives could affect soil rare and abundant sub-communities and enhance physicochemical properties. These findings suggest that applying soil composite amendments based on CHR in the field could improve soil microbial diversity, microbial redundancy, and soil fertility for sustainable agriculture on the Loess Plateau.

Chemical Water Quality and Fish Component Analyses in the Periods of Before- and After-the Weir Constructions in Yeongsan River

  • Kwak, Sang Do;Choi, Ji-Woong;An, Kwang-Guk
    • Journal of Ecology and Environment
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    • 제39권1호
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    • pp.99-110
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    • 2016
  • The objective of this study was to analyze chemical water quality, ecological characteristics of fish compositions, and ecosystem health before- (Bwc; 2008-2009) and after-the weir construction (Awc; 2011-2012) at Juksan Weir and Seungchon Weir of Yeongsan River watershed. Suspended solids (SS) and chlorophyll-a (Chl-a) in Juksan Weir increased, whereas nutrients such as total nitrogen (TN) and total phosphorus (TP) decreased in the epilimnetic water. In Juksan and Seungchon weirs, fish species distribution analysis in the periods of Bwc and Awc showed that sensitive species were rare and tolerant species were dominant in the community. In the analysis of trophic guild, relative abundance of carnivore species are increased to 22% and 12%, respectively, after the constructions of Seungchon Weir and Juksan Weir. Mann-Whitney U-tests of nonparametric statistical analysis indicated that omnivore and carnivore species had significant differences (p < 0.05) between the Bwc and Awc. The massive population growth of an exotic species, Micropterus salmoides, was evident in Seungchon Weir to influence on the structures of fish communities. The model values of mean Index of Biological Integrity (IBI), based on fish assemblages, were < 15, which indicates "poor" condition in the river health, and the significant difference of IBI values was not found between the Bwc and Awc.

2009년 안면도 지역 고농도 PM2.5 특성에 관한 수치 연구 (Numerical Study on the Characteristics of High PM2.5 Episodes in Anmyeondo Area in 2009)

  • 전원배;이화운;이순환;박재형;김현구
    • 한국환경과학회지
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    • 제23권2호
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    • pp.249-259
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    • 2014
  • This paper investigates the characteristics of high $PM_{2.5}$ episodes occurred at Anmyeondo area in spring time, 2009. The monthly mean $PM_{2.5}$ concentration during April was the highest in the year and especially, high levels of $PM_{2.5}$ exceeding standard regulation level were sustained consecutively during 5 to 13 April. To analyze more detailed $PM_{2.5}$ characteristics, numerical simulations were carried out using CMAQ(Community Multi-scale Air Quality) with IPR(Integrated Process Rate) and DDM-3D(Decoupled Direct Method). $PM_{2.5}$ level was lower in daytime than that in nighttime due to vigorous vertical mixing during daytime. The chemical composition was showed that ratio of primary ion components such as sulfate($SO_4{^{2-}}$), nitrate($NO_3{^-}$) and ammonium($NH_4{^+}$) were nearly half of total amount of $PM_{2.5}$. Aerosol and transport process dominantly contributed to $PM_{2.5}$ concentration in Anmyeondo area and contribution rate of local emissions was nearly zero since Anmyeondo area has rare anthropogenic PM emission sources. DDM-3D analysis result showed that $PM_{2.5}$ in Anmyeondo area was influenced by emissions from Shanghai and Shandong region of China.

울릉도 자생 큰연령초의 분포와 자생지의 생태적 특성 (Ecological Characteristics and Distribution of Native Trillium tschonoskii in Ulleung Island)

  • 안영희;이성제;이상현
    • 생약학회지
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    • 제38권2호통권149호
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    • pp.157-163
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    • 2007
  • Trillium tschonoskii Maxim. is a kind of 64 endangered plant species designated by the Ministry of Environment in Korea. It is very a rare native plant throughout the country. Therefore, this study was conducted to investigate the native T. tschonoskii in Ulleung Island for their distribution and ecological characteristics. They were mostly distributed valley, mid-slope of the mountain from 186 to 458 m altitude. They had a little low light conditions as they faced west, north west, south west, south-south west, north-north east and east-east north. They were provided with slightly humid condition. Aerial humidities of these quadrates were variable as 21.5-71%. They were located on the variable slopes of 5 to 43 degrees. Soil humidity was slightly dry. Native sites were semi-shaded because tree layer such as Tilia insularis, Zelkova serrata, okamotoanum etc.and sub-tall tree layer such as Ligustrum foliosum, Comellia japonica, Tilia insularis, Callicarpa japonica and so on were grown near by. Woody plants such as A. Okamotoanum, Sorbus commixta, Fagus japonica var. multinervis etc. were frequently observed. These environmental conditions were suitable that T. tschonoskii grows up naturally because of high Percentage as 52.78% of blooming individuals in this study. These native sites were classified with three communities, T. tschonoskii-Majanthemum dilatatum community, T. tschonoskii-Anthriscus sylvestris community and T. tschonoskii-Hepatica maxima community in accordance with altitude and aerial humidity. The best way ffr the preservation of T. tschonoskii habitats and maintainance of its recent population is maintained in recent environmental condition and ecological condition without any management by human-being.

노조의 사회적 책임에 관한 연구 -LG전자 노동조합 사례를 중심으로- (A Study on the Union Social Responsibility(USR) focused on LG Electronics Union)

  • 김성건;김중화
    • 디지털융복합연구
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    • 제12권2호
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    • pp.193-202
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    • 2014
  • 기업이 살아남기 위해서는 이윤을 추구해야 하는 것 뿐 만 아니라 사회적 책임이 요구된다. 이러한 사회적 책임은 비단 기업 뿐 만이 아니라 기업의 하위시스템인 노동조합에도 사회적 책임이 요구된다. 그러나 이러한 노조의 사회적 책임(Union Social Responsibility, 이하 USR)에 대한 실행사례와 이에 대한 연구는 미미한 것이 사실이다. 노동조합이 지속적으로 생존하고 그 역할을 다하기 위해서는 조합원들만의 기대를 충족시키는 것은 기본이고, 비노조원, 지역사회 등 노동조합과 관련된 이해관계자들의 기대를 충족시켜야 한다. 이에 본 연구에서는 노조의 사회적 책임에 대해 우리나라에서는 선도적이라 할 수 있는 LG전자 노동조합의 USR사례를 살펴보았다. LG전자 노동조합은 2010년 USR을 도입하면서 노동운동의 변화를 추진하였고, 지역사회와 취약계층에 대한 봉사와 파업 자제를 통한 산업평화 확립, 환경보호 등과 같은 내용의 USR을 실천하였으며, 국내 사업장 뿐 만 아니라, LG그룹 내부 및 해외사업장에도 이를 전파하였다. 본 연구에서는 이러한 LG전자 노동조합의 사례를 통해 사회적 존재로서의 노동조합의 새로운 길에 대해 모색하고자 한다.

방글라데시의 생물다양성 보전 및 세계자연유산 (Biodiversity Conservation & World Natural Heritage in Bangladesh)

  • ;이상돈
    • 환경영향평가
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    • 제26권5호
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    • pp.376-384
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    • 2017
  • 방글라데시는 인도히말라야와 인도차이나 경계에 위치한 아열대 몬순기후지역이며 생물다양성 핫스팟으로 알려져 있다. 식생은 활엽수림, 침엽수 및 혼효림으로 구성되어 있으며 습지와 망그로브로 이루어져 있다. 자연경관은 많은 강과 해안선 및 언덕과 농업 산림으로 이루어진 수려한 경관이다. 전 세계적인 선라반이라 불리는 망그로브가 있으며, 이 지역은 방글라데시와 인도 중간에 위치하고 있으며, 1999년 유네스코 세계자연유산지역이다. 망그로브의 62%가 방글라데시에 위치하고 있으며, 많은 동식물이 존재한다. 그러나 많은 사람으로 인해 자연환경이 변화고 있으며, 벌채림이 증가하고, 자연서식자가 감소된다. 이런 이유로 많은 종이 멸종에 처하게 되고 사라진 종도 많다. 이 지역 사람들은 직간접적으로 자연자원에 이익을 얻게 되며, 현재 생태관광이 주 수입원이다. 자연자원의 보호를 위해 정부는 각종 법령을 제정하고 있으며 많은 NGO가 생물다양성과 생태계 보전을 위해 노력하고 있다. 그럼에도 불구하고 현재 접경지역을 통한 오염물질과 자연재해는 방글라데시의 큰 위협요인이다.