Some Modified Biometrical Diversity and Evenness Indices

2020 ◽  
pp. 451-459
Author(s):  
G. Madhusudan ◽  
P. Srivyshnavi ◽  
B. Sarojamma ◽  
M. Naresh ◽  
R. Abbaiah ◽  
...  
Keyword(s):  
Evenness Indices

scholarly journals Assessment of plankton community and environmental conditions in São Sebastião Channel prior to the construction of a produced water outfall

1999 ◽  
Vol 47 (1) ◽  
pp. 29-46 ◽  
Author(s):  
Sônia Maria Flores Gianesella ◽  
Miryam Bertha Burda Kutner ◽  
Flávia Marisa Prado Saldanha-Corrêa ◽  
Mayza Pompeu
Keyword(s):  
Produced Water ◽  
Plankton Community ◽  
Anthropogenic Influence ◽  
Oil And Grease ◽  
Entire Area ◽  
Sampling Points ◽  
Evenness Indices ◽  
Zooplankton Communities ◽  
Neighboring Area ◽  
High Diversity

Plankton community and hydrological conditions were assessed as a part of ao environmental diagnosis in São Sebastião Channel, before the building of a submarine outfall of produced water from the oil maritime terminal of PETR08RÁS. Samples were collected in twenty oceanographic stations located in the oil terminal neighboring area, during the springtime of 1991. Oissolved inorganic nutrients and chlorophyll-a concentrations observed indicate an oligo-mesotrophic environment. Phenols and sulfides were absent, 800 values, except for three sampling points, were characteristic of unpolluted environments, although oil and grease were found in half of the sampled stations. Phytoplankton and zooplankton communities presented high diversity and evenness indices for the entire area. Phytoplankton was dominated by phytoflagel1àtes and zooplankton was dominated by copepods, mostly Paracalanus quasimodo. Plankton community composition was similar to that from adjacent regions under low anthropogenic influence.

scholarly journals Abundance, diversity and distribution of macrophyte communities in neighboring lakes of different trophic states and morphology in north-central Greece

2011 ◽  
Vol 63 (3) ◽  
pp. 763-774 ◽  
Author(s):  
Chrisoula Pirini ◽  
Vasiliki Karagiannakidou ◽  
Savvas Charitonidis
Keyword(s):  
Environmental Factors ◽  
Aquatic Vegetation ◽  
Floristic Composition ◽  
Diversity Indices ◽  
North Central ◽  
Wetland Ecosystems ◽  
Central Greece ◽  
Clear Differentiation ◽  
Evenness Indices

The role of aquatic vegetation in wetland ecosystems is closely related with their abundance, diversity and distribution, which in turn represents synergy of various environmental factors. The floristic composition of the aquatic vegetation in two neighboring lakes (Vegoritida and Petron) in north-central Greece was investigated by means of 160 relev?s, which were recorded using the Braun-Blanquet method. The analysis of relev?s based on TWINSPAN clustering showed the existence of 10 plant communities from the Lemnetea, Potametea, Phragmito-Magnocaricetea and Juncetea maritimi classes. The most important environmental factors for the vegetation differentiation in the study area, according to the ordination diagram, are light intensity and water depth of the habitats. The plant species diversity was quantified with species richness, Shannon Diversity and evenness indices at a scale of each relev?, with a sampling size of 20 m2. There was a clear differentiation between the relev?s at the more eutrophic Petron Lake and those at Vegoritida Lake. The mean plot diversity was also calculated for each plant community, to enable comparison of the diversity indices among the communities at the plot level.

scholarly journals The Biodiversity–Biomass Relationship of Aquatic Macrophytes Is Regulated by Water Depth: A Case Study of a Shallow Mesotrophic Lake in China

2021 ◽  
Vol 9 ◽  
Author(s):  
Fei Ma ◽  
Lei Yang ◽  
Tian Lv ◽  
Zhenjun Zuo ◽  
Haocun Zhao ◽  
...  
Keyword(s):  
Water Depth ◽  
Aquatic Macrophyte ◽  
Interspecific Interactions ◽  
Species Identity ◽  
Community Biomass ◽  
Macrophyte Communities ◽  
Macrophyte Community ◽  
Evenness Indices ◽  
Aquatic Macrophyte Community ◽  
The Relationship

The relationship between biodiversity and productivity (or biomass production) (BPR) has been a popular topic in macroecology and debated for decades. However, this relationship is poorly understood in macrophyte communities, and the mechanism of the BPR pattern of the aquatic macrophyte community is not clear. We investigated 78 aquatic macrophyte communities in a shallow mesotrophic freshwater lake in the middle and lower reaches of the Yangtze River in China. We analyzed the relationship between biodiversity (species richness, diversity, and evenness indices) and community biomass, and the effects of water environments and interspecific interactions on biodiversity–biomass patterns. Unimodal patterns between community biomass and diversity indices instead of evenness indices are shown, and these indicate the importance of both the number and abundance of species when studying biodiversity–biomass patterns under mesotrophic conditions. These patterns were moderated by species identity biologically and water depth environmentally. However, water depth determined the distribution and growth of species with different life-forms as well as species identities through environmental filtering. These results demonstrate that water depth regulates the biodiversity–biomass pattern of the aquatic macrophyte community as a result of its effect on species identity and species distribution. Our study may provide useful information for conservation and restoration of macrophyte vegetation in shallow lakes through matching water depth and species or life-form combinations properly to reach high ecosystem functions and services.

Molecular Analysis of Bacterial Community Structure and Diversity in Unimproved and Improved Upland Grass Pastures

1999 ◽  
Vol 65 (4) ◽  
pp. 1721-1730 ◽  
Author(s):  
Allison E. McCaig ◽  
L. Anne Glover ◽  
James I. Prosser
Keyword(s):  
Community Structure ◽  
Bacterial Community ◽  
Bacterial Community Structure ◽  
Sequence Similarity ◽  
Soil Samples ◽  
Operational Taxonomic Units ◽  
16S Ribosomal Dna ◽  
Pcr Products ◽  
Evenness Indices ◽  
Low Coverage

ABSTRACT Bacterial community structure and diversity in rhizospheres in two types of grassland, distinguished by both plant species and fertilization regimen, were assessed by performing a 16S ribosomal DNA (rDNA) sequence analysis of DNAs extracted from triplicate soil plots. PCR products were cloned, and 45 to 48 clones from each of the six libraries were partially sequenced. Phylogenetic analysis of the resultant 275 clone sequences indicated that there was considerable variation in abundance in replicate unfertilized, unimproved soil samples and fertilized, improved soil samples but that there were no significant differences in the abundance of any phylogenetic group. Several clone sequences were identical in the 16S rDNA region analyzed, and the clones comprised eight pairs of duplicate clones and two sets of triplicate clones. Many clones were found to be most closely related to environmental clones obtained in other studies, although three clones were found to be identical to culturable species in databases. The clones were clustered into operational taxonomic units at a level of sequence similarity of >97% in order to quantify diversity. In all, 34 clusters containing two or more sequences were identified, and the largest group contained nine clones. A number of diversity, dominance, and evenness indices were calculated, and they all indicated that diversity was high, reflecting the low coverage of rDNA libraries achieved. Differences in diversity between sample types were not observed. Collector’s curves, however, indicated that there were differences in the underlying community structures; in particular, there was reduced diversity of organisms of the α subdivision of the class Proteobacteria (α-proteobacteria) in improved soils.

QUANTIFYING SPATIAL PATTERN WITH EVENNESS INDICES

2005 ◽  
Vol 15 (2) ◽  
pp. 507-520 ◽  
Author(s):  
Laura X. Payne ◽  
Daniel E. Schindler ◽  
Julia K. Parrish ◽  
Stanley A. Temple
Keyword(s):  
Spatial Pattern ◽  
Evenness Indices

A quantitative analysis of the state of knowledge of turtles of the United States and Canada

2013 ◽  
Vol 34 (1) ◽  
pp. 11-23 ◽  
Author(s):  
Jeffrey E. Lovich ◽  
Joshua R. Ennen
Keyword(s):  
United States ◽  
Endangered Species ◽  
Conservation Status ◽  
Endangered Species Act ◽  
The United States ◽  
The Body ◽  
Scientific Disciplines ◽  
Evenness Indices ◽  
Access To Knowledge ◽  
Number Of Citations

The “information age” ushered in an explosion of knowledge and access to knowledge that continues to revolutionize society. Knowledge about turtles, as measured by number of published papers, has been growing at an exponential rate since the early 1970s, a phenomenon mirrored in all scientific disciplines. Although knowledge about turtles, as measured by number of citations for papers in scientific journals, has been growing rapidly, this taxonomic group remains highly imperiled suggesting that knowledge is not always successfully translated into effective conservation of turtles. We reviewed the body of literature on turtles of the United States and Canada and found that: 1) the number of citations is biased toward large-bodied species, 2) the number of citations is biased toward wide-ranging species, and 3) conservation status has little effect on the accumulation of knowledge for a species, especially after removing the effects of body size or range size. The dispersion of knowledge, measured by Shannon Weiner diversity and evenness indices across species, was identical from 1994 to 2009 suggesting that poorly studied species remained poorly-studied species while well-studied species remained well studied. Several species listed as threatened or endangered under the U.S. Endangered Species Act (e.g., Pseudemys alabamensis, Sternotherus depressus, and Graptemys oculifera) remain poorly studied with the estimated number of citations for each ranging from only 13-24. The low number of citations for these species could best be explained by their restricted distribution and/or their smaller size. Despite the exponential increase in knowledge of turtles in the United States and Canada, no species of turtle listed under the Endangered Species Act has ever been delisted for reason of recovery. Therefore, increased knowledge does not necessarily contribute appreciably to recovery of threatened turtles.

Diversity, relative abundance, new locality records, and updated fish fauna of the Ross Sea region

2013 ◽  
Vol 25 (5) ◽  
pp. 619-636 ◽  
Author(s):  
Stuart M. Hanchet ◽  
Andrew L. Stewart ◽  
Peter J. McMillan ◽  
Malcolm R. Clark ◽  
Richard L. O'Driscoll ◽  
...  
Keyword(s):  
Ross Sea ◽  
Fish Fauna ◽  
Demersal Fish ◽  
Fish Distribution ◽  
Distribution Data ◽  
Mesopelagic Fish ◽  
Species List ◽  
The North ◽  
Evenness Indices ◽  
Total Species

AbstractTwo surveys were carried out in the Ross Sea region during February and March 2004 and 2008 from the New Zealand RVTangaroa. Fishes were sampled on the continental shelf and slope of the Ross Sea, and on adjacent seamounts to the north, mainly using a large demersal fish trawl and a large mesopelagic fish trawl. Parts of the shelf and slope were stratified by depth and at least three random demersal trawls were completed in each stratum, enabling biomass estimates of demersal fish to be calculated. Fish distribution data from these two surveys were supplemented by collections made by observers from the toothfish fishery. A diverse collection of over 2500 fish specimens was obtained from the two surveys representing 110 species in 21 families. When combined with previous documented material this gave a total species list of 175, of which 135 were from the Ross Sea shelf and slope (to the 2000 m isobath). Demersal species-richness, diversity and evenness indices all decreased going from the shelf to the slope and the seamounts. In contrast, indices for pelagic species were similar for the slope and seamounts/abyss but were much lower for the shelf.

scholarly journals Assessment of Plant Biodiversity at 3 Different Elevation of Protected Forest of Subtropical Pine Forest of Meghalaya

2021 ◽  
Vol 10 (11) ◽  
pp. 157-169
Author(s):  
Damonmi E. Dkhar Afaq Majid Wani
Keyword(s):  
High Elevation ◽  
Economic Importance ◽  
Pine Forest ◽  
Herbaceous Species ◽  
Shrub Species ◽  
Pinus Kesiya ◽  
Medicinal Value ◽  
Indigenous Forest ◽  
Evenness Indices ◽  
Occurrence Of Species

The study and survey which was carried out to identify and assess diversity of plant species of sub tropical pine forest of Meghalaya was conducted during 2020-2021 at three different elevation stands located at 982 m (low-elevation stand), 1485 m (mid-elevation stand) and at 1816 m (high-elevation stand). Pinus kesiya was found to be the most dominant from all the three stand. A total of 34species of trees belonging to 19 families were recorded which consisted a total number of 857 individuals of trees, 14 species of shrubs belonging to 10 families recorded a total number of 866 individuals, and an overall occurrence of 20 species of herbaceous species belonging to 13 families recorded a total number of 670 individuals. Elaeagnus conferta was maximum for IVI in both high and mid elevation stand while Lantana camara showed maximum IVI in the low elevation. The herbaceous species diversity, richness and evenness indices was highest in high elevation and lowest in the low elevation, while herbaceous species of dominance showed a reverse trend. Tree and shrub species of the three elevation stand were quite similar in the mid and low elevation stand. The diversity richness of indigenous forest shows considerable variation in occurrence of species between different altitudes. Most of the species in the study area have medicinal value and socio-economic importance. Therefore, there is a need for necessary action towards sustainability of forest and conservation of species at large.

scholarly journals Community Analysis and Water Quality of Benthic Macroinvertebrates at Gwangseok stream in Korea

2019 ◽  
Vol 4 (1) ◽  
pp. 97-100
Author(s):  
Man Kyu Huh
Keyword(s):  
Water Quality ◽  
Benthic Macroinvertebrates ◽  
Community Analysis ◽  
Macroinvertebrate Community ◽  
Biotic Index ◽  
Benthic Macroinvertebrate ◽  
Biological Water ◽  
Evenness Indices ◽  
Biological Water Quality

The study was to investigate species composition and biological water quality of benthic macroinvertebrates among localities at Gwangseok stream, Jinhae city in Korea. The identified benthic macroinvertebrates were 781 individuals belonged to 19 species, 14 families, 8 orders, 5 classes and 3 phyla. The value of dominance index (DI) was varied from 0.184 (St. C) to 0.333 (St. A) with a mean of 0.235. DI was significantly different among the four regions. Beck-Tsuda's Biotic Index (BI) was varied from 7 (St. D) to 20 (St. C) with a mean of 14. Total ecological score of benthic macroinvertebrate community (TESB) was varied from 12 (St. D) to 38 (St. B) with a mean of 26.3. Average ecological score of benthic macroinvertebrate community (AESB) was varied from 1.714 (St. D) to 1.900 (St. B) with a mean of 1.821. Benthic macroinvertebrate index (BMI) ) was varied from 22.354 (St. A) to 26.474 (St. D) with a mean of 39.756. Shannon-Weaver index (H´) for mammals at the upper regions (St. A and St. B) was higher than those of low regions (St. C and St. D). Berger-Parker’s index (BPI) was varied from 0.218 (St.. C) to 0.346 (St. A). Richness (R1) was different from each other and R2 was not shown significant differences (p < 0.05). Evenness indices (E1-E5) for four stations were different from each other, however there were not shown significant differences (p < 0.05).

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