scholarly journals The Weighted Gini-Simpson Index: Revitalizing an Old Index of Biodiversity

2012 ◽  
Vol 2012 ◽  
pp. 1-10 ◽  
Author(s):  
Radu Cornel Guiasu ◽  
Silviu Guiasu
Keyword(s):  
Relative Abundance ◽  
Joint Distribution ◽  
Concave Function ◽  
Phylogenetic Distance ◽  
Simpson Index ◽  
Additive Partitioning ◽  
Number Of Species ◽  
Conservation Values ◽  
Species Being ◽  
Additive Partitioning Of Diversity

The distribution of biodiversity at multiple sites of a region has been traditionally investigated through the additive partitioning of the regional biodiversity into the average within-site biodiversity and the biodiversity among sites. The standard additive partitioning of diversity requires the use of a measure of diversity, which is a concave function of the relative abundance of species, such as the Gini-Simpson index, for instance. Recently, it was noticed that the widely used Gini-Simpson index does not behave well when the number of species is very large. The objective of this paper is to show that the new weighted Gini-Simpson index preserves the qualities of the classic Gini-Simpson index and behaves very well when the number of species is large. The weights allow us to take into account the abundance of species, the phylogenetic distance between species, and the conservation values of species. This measure may also be generalized to pairs of species and, unlike Rao’s index, this measure proves to be a concave function of the joint distribution of the relative abundance of species, being suitable for use in the additive partitioning of biodiversity. The weighted Gini-Simpson index may be easily transformed for use in the multiplicative partitioning of biodiversity as well.

IMMEDIATE AND LONG-TERM EFFECTS OF INSECTICIDE APPLICATION ON PARASITOIDS IN JACK PINE STANDS IN QUEBEC

1972 ◽  
Vol 104 (2) ◽  
pp. 263-270 ◽  
Author(s):  
Peter W. Price
Keyword(s):  
Relative Abundance ◽  
Jack Pine ◽  
Ground Vegetation ◽  
Long Term Effects ◽  
Aerial Application ◽  
Insecticide Application ◽  
Number Of Species ◽  
Adult Parasitoid ◽  
Pine Stands

AbstractParasitoid populations were sampled before, and for 4 years following, an aerial application of the insecticide phosphamidon to control a sawfly outbreak. Adult parasitoid mortality was high because of spraying, but a reservoir of parasitoids in host cocoons remained to repopulate the treated areas. In moister sites the number of species decreased and their relative abundance changed, but moderate numbers of parasitoids remained 4 years after spraying. In a dry site with little ground vegetation, none of the species present before spraying remained by the fourth year.

scholarly journals Odonates from Bodoquena Plateau: checklist and information about endangered species

2017 ◽  
Vol 17 (3) ◽  
Author(s):  
Ricardo Koroiva ◽  
Marciel Elio Rodrigues ◽  
Francisco Valente-Neto ◽  
Fábio de Oliveira Roque
Keyword(s):  
Endangered Species ◽  
Iucn Red List ◽  
Red List ◽  
Mato Grosso ◽  
Number Of Species ◽  
Red List Species ◽  
Data Deficient ◽  
First Time ◽  
Species Being ◽  
Mato Grosso Do Sul

Abstract Here we provide an updated checklist of the odonates from Bodoquena Plateau, Mato Grosso do Sul state, Brazil. We registered 111 species from the region. The families with the highest number of species were Libellulidae (50 species), Coenagrionidae (43 species) and Gomphidae (12 species). 35 species are registered in the IUCN Red List species, four being Data Deficient, 29 of Least Concern and two species being in the threatened category. Phyllogomphoides suspectus Belle, 1994 (Odonata: Gomphidae) was registered for the first time in the state.

The subgenus Tipula (Pterelachisus) in Finland (Diptera: Tipulidae)—species and biogeographic analysis

Zoosymposia ◽  
2009 ◽  
Vol 3 (1) ◽  
pp. 245-261 ◽  
Author(s):  
JUKKA SALMELA
Keyword(s):  
Central Europe ◽  
Wide Spread ◽  
Positive Relation ◽  
Boreal Species ◽  
National Responsibility ◽  
South Eastern ◽  
Number Of Species ◽  
Area Of Occupancy ◽  
Species Being ◽  
Biogeographic Analysis

A total of 19 Finnish species of the subgenus Tipula (Pterelachisus) are presented. The highest species richnesses are observed in the southern, south eastern and eastern parts of the country and the lowest number of species are found in south western, western and northernmost Finland. This pattern is probably caused by the climate and the eastern Palaearctic origin of several species, but also by differences in forestry history between eastern and western Finland. 16 % of the species are red-listed (NT-VU); these species are confined to primeval heath forests or herb-rich forests and have small distribution areas. 42 % of the species are generally poorly known (NE-DD) and 42 % are rather wide-spread and common (LC). Furthermore, 26 % of the species are National Responsibility Species of Finland; these are boreal species, being absent or rare in Central Europe. The distribution of species in Finland and their area of occupancy is positively correlated. There is also a positive relation between the global range of any species and the extent of its regional occurrence in Finland.

Additive Partitioning of Diversity Reveals No Scale-dependent Impacts of Large Ungulates on the Structure of Tundra Plant Communities

Ecosystems ◽  
2010 ◽  
Vol 13 (1) ◽  
pp. 157-170 ◽  
Author(s):  
V. T. Ravolainen ◽  
N. G. Yoccoz ◽  
K. A. Bråthen ◽  
R. A. Ims ◽  
M. Iversen ◽  
...  
Keyword(s):  
Plant Communities ◽  
Additive Partitioning ◽  
Additive Partitioning Of Diversity

scholarly journals VI.—On the Microzoa Found in Some Jurassic Rocks of England

1886 ◽  
Vol 3 (6) ◽  
pp. 271-274 ◽  
Author(s):  
T. Rupert Jones ◽  
C. D. Shebborn
Keyword(s):  
The South ◽  
Number Of Species ◽  
South West ◽  
Jurassic Rocks ◽  
Being There ◽  
Species Being ◽  
Geological Magazine

In the Geological Magazine, Dec. II. Vol. II. 1875, p. 308, is a list of some English Jurassic Foraminifera, a large number of species being there noted as occurring in these rocks. We have lately received, by the friendly courtesy of the Rev. H. H. Winwood, F.G.S., and Horace B. Woodward, Esq., F.G.S., thirteen specimens of the Jurassic rocks from the south-west of England. One of these has yielded a most important series of Ostracoda. Whilst preparing a special monograph, we hasten to offer some preliminary notes on these interesting Jurassic Microzoa, at present merely noting the genera, in descending order of strata, and deferring the specific nomenclature for a subsequent opportunity.

scholarly journals Undercover speciation of wentletraps (Caenogastropoda: Epitoniidae) in the Southwestern Atlantic

Zootaxa ◽  
2017 ◽  
Vol 4286 (1) ◽  
pp. 41
Author(s):  
DIEGO G. ZELAYA ◽  
MARINA GÜLLER
Keyword(s):  
New Species ◽  
Atlantic Coast ◽  
Intraspecific Variability ◽  
Shell Morphology ◽  
Southwestern Atlantic ◽  
Number Of Species ◽  
Anatomical Characters ◽  
Three New Species ◽  
First Time ◽  
Species Being

Despite being one of the most speciose families, Epitoniidae still remains at present as one of the least understood gastropod families worldwide. This is a consequence of most of the species being only known from shell morphology, added to the wide intraspecific variability of this character and the fact that shell morphology has proven to have frequent examples of parallelisms and convergences among different (unrelated) species. Knowledge of other morphological and anatomical characters in this group is still in its first steps, and such information is currently available for a limited number of species, thus being difficult (when not impossible) to evaluate its taxonomic value. The aim of this study is to re-evaluate the diversity of Epitoniidae occurring in the Atlantic coast of Patagonia. As part of this study, the validity of only four of the six species described / reported from this area could be confirmed: Epitonium georgettinum, E. striatellum, E. fabrizioi and “Cirsotrema” magellanicum. In addition, three new species were recognized and are described herein: Epitonium evanidstriatum, “Cirsotrema” ctenodentatum and “Cirsotrema” strebeli. Information on the shell (including the protoconch), operculum, radula and jaw for these species is here provided, in most cases for the first time. A neotype for Scalaria magellanica is here designated. Furthermore, “Cirsotrema” georgeanum is here proposed as a replacement name for Scalaria fenestrata Strebel, 1908 (not Meneghini in de Stefani, 1875, nor Scalaria fenestrata Wöhrmann, 1889); and that taxon is regarded as a full species, instead of as a synonym of “Cirsotrema” magellanicum, as suggested in some previous publications. This study reveals that the usage of isolated (either morphological or anatomical) characters is usually insufficient for identifying some of the species from Patagonia; however, if these characters are combined, all species may be clearly recognized. 

scholarly journals Monitoring migratory birds in stopover habitat: assessing the value of extended duration audio recording

2020 ◽  
Author(s):  
Ellie Roark ◽  
Willson Gaul
Keyword(s):  
Species Identification ◽  
Relative Abundance ◽  
Migratory Birds ◽  
Survey Method ◽  
List Type ◽  
Point Counts ◽  
Migration Timing ◽  
Number Of Species ◽  
Extended Duration ◽  
Stopover Habitat

ABSTRACTBecause birds are frequently detected by sound, autonomous audio recorders (called automated recording units or ARUs) are now an established tool in addition to in-person observations for monitoring the status and trends of bird populations. ARUs have been evaluated and applied during breeding seasons, and to monitor the nocturnal flight calls of migrating birds. However, birds behave differently during migration stopover than during the breeding season. Here we present a method for using ARUs to monitor land birds in migration stopover habitat.We conducted in-person point counts next to continuously recording ARUs, and compared estimates of the number of species detected and focal species relative abundance from point counts and ARUs. We used a desk-based audio bird survey method for processing audio recordings, which does not require automated species identification algorithms. We tested two methods of using extended duration ARU recording: surveying consecutive minutes, and surveying randomly selected minutes.Desk-based surveys using randomly selected minutes from extended duration ARU recordings performed similarly to point counts, and better than desk-based surveys using consecutive minutes from ARU recordings. Surveying randomly selected minutes from ARUs provided estimates of relative abundance that were strongly correlated with estimates from point counts, and successfully showed the increase in abundance associated with migration timing. Randomly selected minutes also provided estimates of the number of species present that were comparable to estimates from point counts.ARUs are an effective way to track migration timing and intensity in remote or seasonally inaccessible migration stopover habitats. We recommend that desk-based surveys use randomly sampled minutes from extended duration ARU recordings, rather than using consecutive minutes from recordings. Our methods can be immediately applied by researchers with the skills to conduct point counts, with no additional expertise necessary in automated species identification algorithms.

scholarly journals Wildlife-Friendly Livestock Management Promotes Mammalian Biodiversity Recovery on a Semi-Arid Karoo Farm in South Africa

2021 ◽  
Vol 2 ◽  
Author(s):  
Matthew P. E. Schurch ◽  
Jeannine McManus ◽  
Stefan Goets ◽  
Lain E. Pardo ◽  
David Gaynor ◽  
...  
Keyword(s):  
South Africa ◽  
Species Richness ◽  
Relative Abundance ◽  
Positive Impact ◽  
Mammalian Species ◽  
Biodiversity Loss ◽  
Livestock Grazing ◽  
Predator Species ◽  
Livestock Farm ◽  
Number Of Species

Agriculture is an essential production system used to feed the growing human population, but at the same time has become a major driver of biodiversity loss and environmental degradation. Employing production methods that restore degraded landscapes can have a positive impact on biodiversity, whilst improving food production. We assessed how mammalian biodiversity, specifically richness and their relative abundances varied on five Karoo farms in South Africa that had been amalgamated and subjected to a transition from traditional livestock grazing techniques (sporadic rotational grazing and lethal predator control) to wildlife-friendly non-lethal predator management, using human shepherding of livestock under a high-density short-duration grazing regime. We used camera trap data collected over a 4-year period, to measure mammalian species richness, distribution and relative abundance on the wildlife-friendly farm to investigate temporal changes throughout the conversion from traditional farming practices. In the last year of the study (2019) additional cameras were used to provide a spatial comparison of mammalian species on the wildlife-friendly farm to two neighboring farms, a traditional livestock farm using lethal predator controls, and a game farm. We found that mammalian species richness increased year on year resulting in a significant increase of 24% over the duration of the study. Herbivores showed an increase of 33% in the number of species detected over the years, while predator species increased by 8%. The relative abundance and distribution of most species also showed increases as the conversion process took place. For example, 73% of the herbivore species detected throughout the study increased in their relative abundance. Similarly, 67% of all species showed an increase in the number of sites occupied over the years. In the final year of the study the wildlife-friendly farm had more mammalian species compared to the game farm and traditional livestock farm, with the latter two sites having a similar number of species when compared to the commencement of the conversion of the wildlife-friendly site. These broad improvements in mammalian biodiversity demonstrate that livestock production can benefit local mammalian biodiversity through a combination of herder grazing management and wildlife-friendly farming.

scholarly journals Composition and Genetic Diversity of the Nicotiana tabacum Microbiome in Different Topographic Areas and Growth Periods

2018 ◽  
Vol 19 (11) ◽  
pp. 3421 ◽  
Author(s):  
Xiao-Long Yuan ◽  
Min Cao ◽  
Xin-Min Liu ◽  
Yong-Mei Du ◽  
Guo-Ming Shen ◽  
...  
Keyword(s):  
Internal Transcribed Spacer ◽  
Growth Stage ◽  
Fungal Endophytes ◽  
Its Region ◽  
Diversity Indices ◽  
Fungal Communities ◽  
Phylogenetic Distance ◽  
Operational Taxonomic Units ◽  
Number Of Species ◽  
Two Stages

Fungal endophytes are the most ubiquitous plant symbionts on earth and are phylogenetically diverse. Studies on the fungal endophytes in tobacco have shown that they are widely distributed in the leaves, stems, and roots, and play important roles in the composition of the microbial ecosystem of tobacco. Herein, we analyzed and quantified the endophytic fungi of healthy tobacco leaves at the seedling stage (SS), resettling growth stage (RGS), fast-growing stage (FGS), and maturing stage (MS) at three altitudes (600, 1000, and 1300 m). We sequenced the internal transcribed spacer (ITS) region of fungal samples to delimit operational taxonomic units (OTUs) and phylogenetically characterize the communities. The results showed that the numbers of clustering OTUs at SS, RGS, FGS, and MS were 516, 709, 469, and 428, respectively. At the phylum level, species in Ascomycota and Basidiomycota had absolute predominance, representing 97.8% and 2.0% of the total number of species, respectively. We also found the number of fungi at the RGS and FGS stages was higher than those at the other two stages. Additionally, OTU richness was determined by calculating the Observed Species, Shannon, Simpson, Chao1, abundance-based coverage estimator (ACE), Good’s coverage and phylogenetic distance (PD)_whole_tree indices based on the total number of species. Our results showed RGS samples had the highest diversity indices. Furthermore, we found that the diversity of fungal communities tended to decrease with increasing altitude. The results from this study indicated that tobacco harbors an abundant and diverse endophytic fungal community, which provides new opportunities for exploring their potential utilization.

NEW MEASURES FOR COMPARING THE SPECIES DIVERSITY FOUND IN TWO OR MORE HABITATS

2010 ◽  
Vol 18 (06) ◽  
pp. 691-720 ◽  
Author(s):  
RADU CORNEL GUIASU ◽  
SILVIU GUIASU
Keyword(s):  
Shannon Entropy ◽  
Economic Value ◽  
Analytical Formula ◽  
Phylogenetic Distance ◽  
Simpson Index ◽  
Quadratic Index ◽  
The Rich ◽  
Ecological Importance ◽  
Weighted Entropy ◽  
Simple Analytical Formula

Both the weighted entropy, which generalizes the Shannon entropy, and the weighted quadratic index, which generalizes the Gini-Simpson index, are used for getting a unified treatment of some diversity measures proposed recently in ecology. The weights may reflect the ecological importance, rarity, or economic value of the species from a given habitat. The weighted measures, being concave functions, may be used in the additive partition of diversity. The weighted quadratic index has a special advantage over the weighted entropy because its maximum value has a simple analytical formula which allows us to introduce a normed measure of dissimilarity between habitats. A special case of weighted quadratic index is the Rich-Gini-Simpson index which, unlike the Shannon entropy and the classic Gini-Simpson index, behaves well when the number of species is very large. The weighted entropy and the weighted quadratic index may also be used to measure the global diversity among the subsets of species. In this context, Rao's quadratic index of diversity between the pairs of species, based on the phylogenetic distance between species, is obtained as a particular case and is generalized to measure the diversity among the triads of species as well.

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