• 제목/요약/키워드: Simpson's indices

검색결과 24건 처리시간 0.021초

Diversity of Subcortical Arthropod Communities in Tropical and Temperate Forests

  • 조재천
    • Animal cells and systems
    • /
    • 제1권4호
    • /
    • pp.577-581
    • /
    • 1997
  • Species diversity of subcortical arthropod communities were assessed in two tropical regions and two temperate regions. In the tropics, communities of subcortical arthropods were more diverse in La Selva, Costa Rica, than on Barro Colorado Island, Panama. Costa Rican communties yielses higher values of both Shannon and Simpson diversity indices than Panamanian communities. Compared to Panamanian communities, Costa Rican ones supported higher measures of both species richness and evenness. Between the two temperate regions, communities of subcortical arthropods in Korea scored consistently higher values of both Shannon and Simpson indices than the ones in eastern Massachusetts, U.S.A. When individual diversity components were compared, however, Korean communities yielded exceptionally high evenness measures but lower species richness than the communities in the U.S.A. Unusually high evenness values of Korean subcortical arthropods were due to extremely low population densities of all component species.

  • PDF

Investigation Plant Species Diversity and Physiographical Factors in Mountain Forest in North of Iran

  • Hashemi, Seyed Armin
    • Journal of Forest and Environmental Science
    • /
    • 제26권1호
    • /
    • pp.1-7
    • /
    • 2010
  • Species diversity is one of the most important specifications of biological societies. Diversity of organisms, measurement of variety and examination of those hypotheses that are about reasons of diversity are such as affairs that have been desired by the ecologists for a long time. In this research, diversity of plant species in forest region, numbers of 60 sample plots in 256.00 square meters have been considered in random - systematic inventory was considered. In each sample plot, four micro-plots in 2.25 square meters in order to study on herbal cover, were executed that totally 240 micro-plots were considered. At each plot six diversity indices in relation to physiographic factors (slope, geographical aspect and altitude from the sea level) were studied. The results indicate that species diversity is more in the northern direction and also species diversity in slops less than 30% has the most amounts. Factor of altitude from the sea level did not have meaningful relation with species diversity. Through study on correlation of the numbers of species in sample plots with indices and also process and role of indices in different processors of analysis, Simpson's reciprocal index was suggested as suitable index in this type of studies.

Deciphering Diversity Indices for a Better Understanding of Microbial Communities

  • Kim, Bo-Ra;Shin, Jiwon;Guevarra, Robin B.;Lee, Jun Hyung;Kim, Doo Wan;Seol, Kuk-Hwan;Lee, Ju-Hoon;Kim, Hyeun Bum;Isaacson, Richard E.
    • Journal of Microbiology and Biotechnology
    • /
    • 제27권12호
    • /
    • pp.2089-2093
    • /
    • 2017
  • The past decades have been a golden era during which great tasks were accomplished in the field of microbiology, including food microbiology. In the past, culture-dependent methods have been the primary choice to investigate bacterial diversity. However, using culturein-dependent high-throughput sequencing of 16S rRNA genes has greatly facilitated studies exploring the microbial compositions and dynamics associated with health and diseases. These culture-independent DNA-based studies generate large-scale data sets that describe the microbial composition of a certain niche. Consequently, understanding microbial diversity becomes of greater importance when investigating the composition, function, and dynamics of the microbiota associated with health and diseases. Even though there is no general agreement on which diversity index is the best to use, diversity indices have been used to compare the diversity among samples and between treatments with controls. Tools such as the Shannon-Weaver index and Simpson index can be used to describe population diversity in samples. The purpose of this review is to explain the principles of diversity indices, such as Shannon-Weaver and Simpson, to aid general microbiologists in better understanding bacterial communities. In this review, important questions concerning microbial diversity are addressed. Information from this review should facilitate evidence-based strategies to explore microbial communities.

Some Proposed Indices of Structural Regeneration of Secondary Forests and Their Relation to Soil Properties

  • Aweto, Albert Orodena
    • Journal of Forest and Environmental Science
    • /
    • 제37권4호
    • /
    • pp.292-303
    • /
    • 2021
  • Studies that relate the structure of tropical regrowth vegetation to soil properties are generally lacking in the literature. This study proposes three indices for assessing the structural regeneration of secondary forests. They are: (1) the tree diameter class, (2) the plant life form and (3) the woody/herbaceous plants ratio indices. They were applied to assess the regeneration status of forest regrowth vegetation (aged 1-10 years), derived savanna regrowth vegetation in south western Nigeria, and to secondary forests in different stages of succession in Columbia and Venezuela, Bolivia, Mexico in South and Central America and semi-arid savanna in Ethiopia and seasonal deciduous forest successional stages in India. In all the cases, the indices increased with increasing age of regrowth vegetation and hence, with increasing structural complexity of regenerating vegetation. The tree diameter class index increased from 32.1% in a 9-year secondary forest to 69.0% in an 80-year-old secondary forest in Columbia and Venezuela and from 0.4% in a 1-year fallow to 20.9% in 10-year regrowth vegetation in southwestern Nigeria. In semi-arid savanna in northern Ethiopia, the woody/herbaceous plants ratio index increased from 18.1% in a 5-year protected grazing enclosure to 75.1% in 15-year protected enclosure, relative to the status of 20-year enclosure. The indices generally had correlations of 0.6-0.90 with species richness and Simpson's/Margalef's species diversity, implying that they are appropriate measures of ecosystem development over time. The proposed indices also had strong and positive correlations with soil organic carbon and nutrients. They are therefore, significant indicators of fertility status.

보행성 딱정벌레류의 다양성 및 풍부도에 관한 연구 -경북 상주시 갑장산- (Diversity and Abundance of Ground-beetles (Coleoptera) in Mt. Gabjangsan, Korea)

  • 박종균;연화순;담휴착
    • 한국토양동물학회지
    • /
    • 제8권1_2호
    • /
    • pp.32-36
    • /
    • 2003
  • 상주시에서 위치한 갑장산(805.7 m)을 대상으로 고도 200m부터 800m까지 100m 간격으로 7개의 시험구를 설정하여 2001년 8월부터 2001년 10월까지 당밀을 이용한 pitfall trap를 설치하여 고도별, 계절별 다양도 및 우점도 지수를 알아보았다. 그 결과 먼지벌레와, 딱정벌레과 그리고 송장벌레과에 속한 곤충들이 채집되었고, 전체 6,304개체 중 먼지 벌레과가 6,163개체로 98% 이상을 차지하였다. 고도 200m부터 700m까지 점차적으로 개체수의 증가추세를 보이다가 800m에서 급격하게 감소하였다. 고도 700m에서 심슨의 우점도지수는 0.66으로 가장 높게 나타났으며, 800m에서 0.47로 가장 낮게 나났다. 반면 심슨의 다양도 지수는 800m에서 0.53으로 가장 높게 나타났다. 계절별 우점도 및 다양도 지수는 0.54에서 0.55로 큰 차이를 발견할 수 없었으며, 과 별 다양도지수는 먼지벌레과에서 가장 높았다.

  • PDF

Diversity and Composition of Tree Species in Madhupur National Park, Tangail, Bangladesh

  • Rahman, Md. Rayhanur;Hossain, Mohammed Kamal;Hossain, Md. Akhter
    • Journal of Forest and Environmental Science
    • /
    • 제35권3호
    • /
    • pp.159-172
    • /
    • 2019
  • Madhupur National Park (MNP) is one of the last remaining patches of old-growth natural Sal forest left in Bangladesh where the forest is tropical moist deciduous type. A study was revealed to assess the tree species diversity and composition in this area. For determining tree species the study was conducted through extensive random quadrat survey methods with $20m{\times}20m$ sized plots. Results of the study indicated that there were 139 tree species belonging to 100 genera and 40 families. The quadrat survey assessed the basal area, stem density, diversity indices and importance value index of the tree species having ${\geq}5cm$ D.B.H (Diameter at Brest Height). The basal area and stem density of the tree species were $20.689{\pm}1.08m^2/ha$ and $1412.93{\pm}64.27stem\;ha^{-1}$ while, diversity indices, i.e. Shannon-Wiener's diversity, Simpson's evenness, Margalef's species richness and Pielou's dominance indices indicated poor diversity in comparison to that of other PAs (Protected Areas) in South-Eastern region of Bangladesh. The structural composition based on height and D.B.H through reverse-J shaped curve indicated higher regeneration and recruitment but removal of trees of large growth classes. Sal (Shorea robusta) was the most dominant tree species that accounts 75% of the total tree individuals in the natural forest patches. However, some associates of Sal, i.e. Bhutum (Hymenodictyon orixensis), Gadila (Careya arborea), and Kusum (Schleichera oleosa) etc. were seemed to be rare in MNP.

독도의 토양 선충상 (Soil Nematode Fauna in Dokdo Island of Korea)

  • 김동근;박병용;류영현
    • 식물병연구
    • /
    • 제18권4호
    • /
    • pp.381-386
    • /
    • 2012
  • 독도 생태 연구의 일환으로 2008-2009년 2개년간 독도의 토양을 채집하고 선충의 종류, 밀도, 식이습성군, 생태지수 등의 연구를 수행하였다. 독도에서 총 31종의 선충이 발견되었으며 평균 밀도는 $m^2$당 239,500마리(26,000-836,000)였고 biomass는 $103.9mg/m^2$(3.0-388.6)였다. 중요도는 Acrobeloides 속이 Prominence value(PV) 117.8로 가장 높았고 다음으로 Rhabditidae(PV = 81.9), Prismatolaimus(PV = 39.0), Aphelenchoides(PV = 31.4) 순이었다. Feeding Group별로는 세균성선충이 전체 선충 중에서 밀도로는 77%, biomass로는 62%를 차지하여 가장 중요한 그룹이었고 다음으로는 식물기생성선충과 식균성선충류였다. 동도 참소리쟁이에서 발견된 뿌리썩이선충은 신종으로 추정된다. 독도 선충의 생태적 분석 결과 Shannon and Wiener 지수(2.46), Simpson's diversity 지수(0.86), 종 균일도(0.73), 종 풍부성(1.30)을 볼 때 독도의 선충상은 종이 풍부하고, 다양한 것이 특징이며, 독도만의 독특한 생태계를 유지하고 있다고 하겠고 이것은 경작되지 않고 자연 그대로 보존된 원시적 환경의 특징이다. 이번의 조사 결과는 독도의 생태적 모니터링에 기초자료로 활용되어질 수 있을 것이다.

이앙답(移秧畓)에서 제초제(除草劑)의 혼합(混合), 조합처리(組合處理)가 제초효과(除草效果) 및 벼 수량(收量)에 미치는 영향 (Effects of Mixture and Systematic Application of Herbicides on Weed Control and Yield in Transplanted Rice)

  • 김제규;구연충;이종훈
    • 한국잡초학회지
    • /
    • 제2권1호
    • /
    • pp.20-30
    • /
    • 1982
  • 본(本) 시험(試驗)은 1981년(年) 작물시험장(作物試驗場) 답작포장(畓作圃場)에서 Indica${\times}$Japonica 원록교잡종(遠綠交雜種)인 태백(太白)벼(수원(水原) 287호(號))를 기계이앙(機械移秧)하여 제초제(除草劑)의 살초효과((殺草効果) 증대(增大)를 위한 기초연구(基礎硏究)로서 제초제종류(除草劑種類)에 따른 초종(草種)의 다양화(多樣化)와 초종구성(草種構成)의 유사성정도(類似性程度)를 조사(調査), 분석(分析)하여 제초제(除草劑)를 혼합(混合) 또는 조합처리(組合處理)하거나 혼합제초제(混合除草劑)를 만들 때 약제선택(藥劑選擇)에 필요(必要)한 정보(情報)를 얻고자 우점초종(優占草種)이 피, 올방개, 올챙고랭이이며 이들의 우점도(優占度)가 각각(各各) 89%, 5%, 3%였던 시험포장(試驗圃場)에서 실시(實施)하였던 바 그 결과(結果)를 요약(要約)하면 다음과 같다. 1. 약해(藥害)는 혼합제초제(混合除草劑)가 단일제초제(單一除草劑)에 비(比)하여 더 많은 경향(傾向)이었다. 2 단일제초제(單一除草劑)의 사용(使用)보다는 살초(殺草) spectrum이 서로 다른 두가지의 유효성분(有效成分)을 혼합(混合)한 혼합제초제(混合除草劑)를 사용(使用)하는 것이, 또 벼 이앙(移秧) 전후(前後)에 제초제(除草劑)를 한번 사용(使用)하는 것보다는 이쾌전후(移快前後)와 생육중기(生育中期)에 제초제(除草劑)를 두번 조합처리(組合處理)하는 것이 제초효과면(除草効果面)에서 더 우수(優秀)하였다. 3. 제초제처리(除草劑處理)에 의한 초종(草種)의 다양화(多樣化) 정도(程度)는 Simpson 지수(指數)가 높은 Butachlor(3.5G)/SL-49(7G), Butachlor(3.5G)/Pyrazolate(6G) 및 Perfluidone(5G)과 같은 제초제(除草劑)는 잡초군락(雜草群落) 단순화(單純化)시키는 경향(傾向)이며, Simpson 지수(指數)가 낮은 Perfluidone(5G) + Chloromethoxynil(7G), Butachlor(6G) fb Perfluidone(5G), 및 Butachlor(4G)/Naproanilide(6G)와 같은 약제(藥劑)는 초종(草種)을 다양화(多樣化)시키는 경향(傾向)이었다. 4. 초종구성유사성계수(草種構成類似性係數)로 볼 때 제초효과(除草効果)를 가장 높일 수 있는 약제(藥劑)는 초종구성(草種構成)이 크게 달랐던 Perfluidone(5G)과 Chloromethoxynil(7G), Bifenox(7G) 및 Butachlor(6G)의 혼합제초제(混合除草劑)로 추정(推定)되며, Perfluidone(5G)은 타(他) 약제(藥劑)와의 유사성계수(類似性係數)가 대체(大體)로 낮은 경향(傾向)이었다. 5. 제초효과(除草效果)가 우수(優秀)하고 벼 수량(收量)(현미중(玄米重))이 손 제초구(除草區)와 비슷하였던 처리(處理)는 Perfluidone(5G), Butachlor (3G)/Chloromethoxynil(6G), Perfluidone(5G) + Chloromethoxynil(7G), Butachlor(6G) fb Bentazon(40 E. C) 및 Butachlor(6G) fb Perfluidone(5G) 처리(處理)였다.

  • PDF

차세대 염기서열 분석법을 이용한 된장과 간장의 미생물 분포 및 바이오마커 분석 (Comparative Microbiome Analysis of and Microbial Biomarker Discovery in Two Different Fermented Soy Products, Doenjang and Ganjang, Using Next-generation Sequencing)

  • 하광수;정호진;노윤정;김진원;정수지;정도연;양희종
    • 생명과학회지
    • /
    • 제32권10호
    • /
    • pp.803-811
    • /
    • 2022
  • 우리나라 전통 콩 발효식품은 탄수화물을 주식으로 하는 한국인의 식생활에 중요한 단백질 급원임에도 불구하고 콩 발효식품의 미생물 다양성과 군집 구조에 대해서는 거의 알려진 바가 없다. 본 연구는 16S rDNA 유전자 서열 분석 기반의 차세대 염기서열 분석법을 이용하여 한국 전통 발효식품인 된장과 간장의 미생물 군집 구조를 밝히고자 하였다. Alpha-diversity 분석 결과 미생물 다양성 지표인 Shannon과 Simpson에서 된장과 간장의 미생물 다양성에 통계학적인 차이가 있는 것으로 나타났으나, 종 풍부도 지표인 ACE, CHAO, Jackknife에서는 차이가 없는 것으로 나타났다. 된장과 간장의 미생물 분포 분석 결과 된장과 간장의 공통적인 우점균은 Firmicutes로 나타났으나, 속 수준에서의 미생물 분포를 분석한 결과 된장에서 Bacillus, Kroppenstedtia, Clostridium, Pseudomonas가 간장보다 높은 비율을 차지하고 있는 것으로 나타났으며, 간장에서는 Tetragenococcus, Chromhalobacter, Lentibacillus, Psychrobacter와 같은 호염성 또는 내염성 세균이 된장보다 높은 비율을 차지하는 것으로 나타났다. 된장과 간장의 미생물 군집구조에 통계학적인 차이가 있는지 확인하기 위해 paired-PERMANOVA 분석을 수행하였으며, 그 결과 통계학적으로 매우 유의한 수준의 차이가 있는 것으로 나타났다. 된장과 간장의 미생물 군집구조 차이에 큰 영향을 미치는 biomarker를 분석하기 위해 LEfSe 분석을 수행하였으며, 그 결과 Bacillus와 Tetragenococcus가 된장과 간장의 미생물 군집 구조에 차이를 나타내는 biomarker로 분석되었다.

산림 내에서 곤충의 현존도와 식충목 4 종의 풍부도간의 상관 관계 (Relationships between Invertebrate Availability and the Abundance of Three Species of Shrews and the Shrew-mole in Managed Forests)

  • Lee, Sang Don
    • The Korean Journal of Ecology
    • /
    • 제18권4호
    • /
    • pp.441-449
    • /
    • 1995
  • The abundance of coarse woody debris (CWD) has been hypothesized to increase niche for forest dwelling insectivores, concentration of nutrients, and the diversity of invertebrates. However, no abjective assessment based on replication in the field has yet been done. this study was carried out to test the relationships between invertebrate availability and the abundance of four insectivores (Sorex trowbridgii, S. vagrans, S. monticolus and Neurotrichus gibbsii) in western Washington, USA. Pitfall traps were used to determine abundance and diversity of invertebrates. Abundance of insectivores was not different between habitats except for S. vagrans which was more abundant in habitats with low amounts of CWD than in habitats with high amounts of CWD. Simpson’s diversity index computed for invertebrates did not differ between habitats. There were no significant relationships between the diversity indices of invertebrates and the abundance of shrews. Shrew abundance and the Coleoperan beetles also did not show any significant relationship. The results suggested insectivores might select a wide range of prey items in addition to surface-active invertebrates.

  • PDF