scholarly journals The system of faunacomponents conception and its application to qualify the degree of naturalness of fish assemblages

2007 ◽  
pp. 93-101
Author(s):  
Péter Sály

The increase of species richness in communities of natural biogeographic regions in an anthropogenic way can be expressed as biogeographic pollution. Where there is contaminated fauna, one must investigate how this occured. I studied how the members of Hungarian fishfauna could be present resident and have managed to workout a so-called system of fauna component conception which is suitable for this requirement.The expression of ’faunacomponent’ includes other expressions. That kind of species belong to a certain faunacomponent that reached the studied area in the same way. Species reached the studied area without an anthropogenious contribution are qualified as native fauna components. These kind of species are endemic species, occasional species and settlers. In contrast to native faunacomponents, some kind of human influence is always detectable in connection with the way reached the studied area by non-native species. Accordingly, group of non-native species includes directly or indirectly facilitated settlers, species that are introduced accidentally and those introduced intentionally. It is obvious that classifying a given species could be construed solely in connection with a certain area.Applying Shannon diversity index I have initiated the assemblage natural index (ANI) in order to show a way how to use the system of faunacomponent conception in practice. ANI refers to the degree of naturalness of faunistical samples. If ANI > 1 it means there are not any non-native species and ANI < 1 it means there are some non-native species in the sample respectively. In the latter case ANI decreases proportionally with the number of non-native species and specimens. In that special case when only one specimen of only one non-native species can be found in the faunistical sample ANI = 1.

2016 ◽  
Vol 51 (8) ◽  
pp. 958-966 ◽  
Author(s):  
Anderson Pedro Bernardina Batista ◽  
José Márcio de Mello ◽  
Marcel Régis Raimundo ◽  
Henrique Ferraço Scolforo ◽  
Aliny Aparecida dos Reis ◽  
...  

Abstract: The objective of this work was to analyze the spatial distribution and the behavior of species richness and diversity in a shrub savanna fragment, in 2003 and 2014, using ordinary kriging, in the state of Minas Gerais, Brazil. In both evaluation years, the measurements were performed in a fragment with 236.85 hectares, in which individual trees were measured and identified across 40 plots (1,000 m2). Species richness was determined by the total number of species in each plot, and diversity by the Shannon diversity index. For the variogram study, spatial models were fitted and selected. Then, ordinary kriging was applied and the spatial distribution of the assessed variables was described. A strong spatial dependence was observed between species richness and diversity by the Shannon diversity index (<25% spatial dependence degree). Areas of low and high species diversity and richness were found in the shrub savanna fragment. Spatial distribution behavior shows relative stability regarding the number of species and the Shannon diversity index in the evaluated years.


2015 ◽  
Vol 7 (15) ◽  
pp. 8272 ◽  
Author(s):  
Girish Gogoi ◽  
Vipin Parkash

<p>Hollongapar Gibbon Wildlife Sanctuary is comprised of five distinct compartments.  A total of 138 species of gilled mushrooms belonging to 48 genera, 23 families, five orders of the class Agaricomycetes, division Basidiomycota, have been collected and analyzed. The order Agaricales was was found with the highest number of species (113), followed by Russulales (14), Polyporales (5), Cantharellales (4) and Boletales (2). The species <em>Coprinellus disseminatus </em>and <em>Megacollybia rodmani</em> have shown the highest (8.26) and the lowest density (0.05), respectively.  A total of 24 species, e.g., <em>Termitomyces albuminosus, Marasmius curreyi, Marasmiellus candidus, Leucocoprinus medioflavus, Mycena leaiana, Hygrocybe miniata, Collybia chrysoropha, Gymnopus confluens</em> were common with frequency percentage of 11.9, whereas <em>Megacollybia rodmani</em> with less frequency percentage (2.4) was found only in few quadrates of the sanctuary.  The highly abundant species were <em>Termitomyces medius</em> (91.7) and <em>Coprinellus disseminatus </em>(86.8), and less abundant species were <em>Psilocybe wayanadensis</em> (1.0) and <em>Lepiota</em> sp. (1.0) in the study site.  The order of the species richness index (<em>R</em>) compartment wise was 2&gt;3&gt;4&gt;5&gt;1. Both the Shannon diversity index and Simpson diversity index of agarics was maximum (1.88, 0.98) in compartment 2, whereas minimum (1.72, 0.95) in compartment 1 and 5, respectively.  Moreover, the compartment 2 was found very much similar with compartment 3 and very less similar with compartment 1.</p><div> </div>


2020 ◽  
Author(s):  
Annissa Muhammed ◽  
Eyasu Elias

Abstract Background: This study aimed to determine the effects of landscape change on floristic composition, diversity, and structure in the Bale mountains national park, which faces a critical challenge from anthropogenic factors. The park is one of the 34 International Biodiversity Hotspots that comprise a variety of life forms. The vegetation data were collected systematically from 96 sample plots laid along 24 line transects. Vegetation composition and landscape structural analysis were made using R software version 3.5.2 and FRAGSTATS version 4.2.1, respectively.Results: Patch number was strong and positively affected species richness (r = -0.90, p < 0.05) and Shannon diversity index (r = -0.96, p < 0.01), and basal area (r = -0.96, p < 0.001), whereas mean patch size was strong and positively influenced species richness (r = 0.95, p < 0.05), diversity (r = 0.87, p < 0.05), and basal area (r = 0.82, p < 0.05). The overall species richness, Shannon diversity index, and Margalef index were significantly higher in the edge habitat than the interior at p < 0.05. However, the mean basal area of woody species in the interior habitat (11.16 ± 1.82 m2 ha-1) was significantly higher than the edge (3.99 ± 0.54 m2 ha-1) at p < 0.05.Conclusion: This study revealed that the park was a biologically diverse and ecologically significant area that provides a variety of ecological and economic benefits to the surrounding communities. Though its habitats are changing alarmingly and urgent restoration and conservation action need to be taken to reverse this situation.


2020 ◽  
Vol 35 (1) ◽  
pp. 11-20
Author(s):  
Tulsi Raj Adhikari ◽  
Shubha Ratna Shakya ◽  
Shambhu Adhikari ◽  
Indra Prasad Subedi

The study assesses the diversity of ground-dwelling ants (Hymenoptera: Formicidae) in Phulchowki Hill, Lalitpur, Nepal focusing their species richness altitudinally and seasonally. Ants were sampled from June 2018 to February 2019using pitfall traps, bait traps and hand collection methods covering an altitudinal range from 1500 m to 2700 m in five selected sites (1500 m, 1800 m, 2100 m,2400 m, and 2700 m). A total of 1443 specimens representing four subfamilies, 12genera and 18 morph species were collected. Formicinae (57.58%) was recorded as the most abundant subfamily followed by Myrmicinae (38.53%), Ponerinae (2.21%) and Pseudomyrmicinae (1.66%). Camponotus was the most speciose (4morphospecies) genus and was most abundant in all seasons. The highest Similarity index (0.667) was recorded between the first and second sites among five sites. Species richness (16), Shannon diversity index (1.504) and abundance (631) were the highest in autumn. Similarly, species richness (12), Shannon diversity index (1.399) and species evenness (0.563) were recorded highest at 2100 m altitude, while species abundance (519) was maximum at 1500 m.


2021 ◽  
Author(s):  
Wakshum Shiferaw

AbstractThe study aimed to assess (i) the effects of Prosopis juliflora invasion on the diversity of plant species, and floristic composition at Awash Fentale and the Amibara districts of the Afar region and (ii) the effects of P. juliflora invasion on the regeneration potential of native woody species. Sample collection was performed in habitats of P. juliflora thicket, P. juliflora mixed with native species stands, non-invaded woodlands, and open grazing lands. A stratified random sampling technique was used for data collection. Among species of plants, the highest proportion of species, 87 (27.4%), was recorded under non-invaded woodlands, but the lowest proportion of species, 70 (22%), was recorded under open grazing lands. The invasion level of P. juliflora caused significantly reduced Shannon diversity index. The mean values of Shannon diversity index and species richness under P. juliflora mixed with native species (H’=2.22, R=14) and non-invaded woodlands (H’=2.23, R=13) were significantly higher than P. juliflora thicket (H’=1.96, R=12) and open grazing lands (H’=1.84, R=10). In this study, 102 trees ha-1native woody species were recorded under P. juliflora thicket, but 1252 trees ha-1native species were recorded under non-invaded woodlands. If the present effects of the invasion of P. juliflora on native species diversity were to continue coupled with a drier climate, plant diversity of the Afar flora region will be highly affected. As a result the ecosystem services will be under threat. Thus, the participation of all stakeholders and multidisciplinary research approaches should be designed for the management of invaded rangelands to reverse the situation.


2022 ◽  
Author(s):  
Muhidin Tahir ◽  
Yemane G. Egzabher ◽  
Meheretu Yonas ◽  
Kidane Giday ◽  
Hayal Lemma ◽  
...  

Abstract This research was conducted in Afro-alpine vegetation of Abohoy Gara Mountain in northern Ethiopia with the aim of analyzing floristic composition along elevational gradients, threats and conservation methods. Data were collected from 53 quadrats (15 m x 15 m) laid at 100 m interval along parallel vertical transects spaced at 500m to each other to record shrubs and trees, whereas 1 m x 1 m plots were used to record herbs. Cover abundance data were used to do community analysis using R version 3.1.2 software. Analysis of variance (ANOVA) was employed to determine significant level of species richness; abundance and Shannon diversity index along elevational gradient, whereas pearson’s correlation test was applied to check the relationship between environmental variables with species richness, species abundance and Shannon diversity index (H’) using SPSS v20. Ninety-seven plant species composed of 82 genera under 40 families were recorded. The mean number of plant species showed significant difference along elevational gradient (P < 0.05). Besides, significant (P < 0.05) negative correlation of elevation with the plant richness, abundance as well as Shannon diversity index had been observed. Based on dominant species, a total of five plant communities were identified. The maximum plant diversity occurred in community type III (3.79), whereas the least plant diversity occurred in community type IV and community type V. Vegetation cover and species composition of Abohoy Gara Mountain is being endangered by agricultural expansion, over grazing and logging of wood for construction material. Hence, it needs application of complementary on-site and offsite conservation approaches. This calls for further joint management of the Abohoy Gara Mountain by the local people and administrative bodies in the overall conservation actions that can save and rehabilitate the plant resources and their habitats.


Entropy ◽  
2021 ◽  
Vol 23 (4) ◽  
pp. 464
Author(s):  
Frank Nielsen

We generalize the Jensen-Shannon divergence and the Jensen-Shannon diversity index by considering a variational definition with respect to a generic mean, thereby extending the notion of Sibson’s information radius. The variational definition applies to any arbitrary distance and yields a new way to define a Jensen-Shannon symmetrization of distances. When the variational optimization is further constrained to belong to prescribed families of probability measures, we get relative Jensen-Shannon divergences and their equivalent Jensen-Shannon symmetrizations of distances that generalize the concept of information projections. Finally, we touch upon applications of these variational Jensen-Shannon divergences and diversity indices to clustering and quantization tasks of probability measures, including statistical mixtures.


Author(s):  
Sumayyah Aimi Mohd Najib

To determine the soil erosion in ungauged catchments, the author used 2 methods: Universal Soil Loss Equation model and sampling data. Sampling data were used to verify and validate data from model. Changing land use due to human activities will affect soil erosion. Land use has changed significantly during the last century in Pulau Pinang. The main rapid changes are related to agriculture, settlement, and urbanization. Because soil erosion depends on surface runoff, which is regulated by the structure of land use and brought about through changes in slope length, land-use changes are one of many factors influencing land degradation caused by erosion. The Universal Soil Loss Equation was used to estimate past soil erosion based on land uses from 1974 to 2012. Results indicated a significant increase in three land-use categories: forestry, built-up areas, and agriculture. Another method to evaluate land use changes in this study was by using landscape metrics analysis. The mean patch size of built-up area and forest increased, while agriculture land use decreased from 48.82 patches in 1974 to 22.46 patches in 2012. Soil erosion increased from an estimated 110.18 ton/km2/year in 1974 to an estimated 122.44 ton/km2/year in 2012. Soil erosion is highly related (R2 = 0.97) to the Shannon Diversity Index, which describes the diversity in land-use composition in river basins. The Shannon Diversity Index also increased between 1974 and 2012. The findings from this study can be used for future reference and for ungauged catchment research studies.


<em>Abstract.</em>—We examined fish assemblage responses to urban intensity gradients in two contrasting metropolitan areas: Birmingham, Alabama (BIR) and Boston, Massachusetts (BOS). Urbanization was quantified by using an urban intensity index (UII) that included multiple stream buffers and basin land uses, human population density, and road density variables. We evaluated fish assemblage responses by using species richness metrics and detrended correspondence analyses (DCA). Fish species richness metrics included total fish species richness, and percentages of endemic species richness, alien species, and fluvial specialist species. Fish species richness decreased significantly with increasing urbanization in BIR (<em>r </em>= –0.82, <EM>P </EM>= 0.001) and BOS (<em>r </em>= –0.48, <EM>P </EM>= 0.008). Percentages of endemic species richness decreased significantly with increasing urbanization only in BIR (<em>r </em>= – 0.71, <EM>P </EM>= 0.001), whereas percentages of fluvial specialist species decreased significantly with increasing urbanization only in BOS (<em>r </em>= –0.56, <EM>P </EM>= 0.002). Our DCA results for BIR indicate that highly urbanized fish assemblages are composed primarily of largescale stoneroller <em>Campostoma oligolepis</em>, largemouth bass <em>Micropterus salmoides</em>, and creek chub <em>Semotilus atromaculatus</em>, whereas the highly urbanized fish assemblages in BOS are dominated by yellow perch <em>Perca flavescens</em>, bluegill <em>Lepomis macrochirus</em>, yellow bullhead <em>Ameiurus natalis</em>, largemouth bass, pumpkinseed <em>L. gibbosus</em>, brown bullhead <em>A. nebulosus</em>, and redfin pickerel <em>Esox americanus</em>. Differences in fish assemblage responses to urbanization between the two areas appear to be related to differences in nutrient enrichment, habitat alterations, and invasive species. Because species richness can increase or decrease with increasing urbanization, a general response model is not applicable. Instead, response models based on species’ life histories, behavior, and autecologies offer greater potential for understanding fish assemblage responses to urbanization.


2016 ◽  
Vol 12 (3) ◽  
pp. 119-130 ◽  
Author(s):  
A.H.D. Janabi ◽  
A.S. Biddle ◽  
D. Klein ◽  
K.H. McKeever

Exercise has a significant effect on different physiological systems in the body of human and animals. Only limited numbers of published studies in laboratory animals or humans have shown the effect of exercise on the gut microbiota, and no studies have shown this effect in horses. In this study, 8 horses (4 mares, 4 geldings) were exercise trained for 12 weeks, and 4 additional mares were used as a parallel seasonal control. To identify bacterial community changes over time for both groups, rectal faecal samples were collected, DNA was extracted, and the 16S rRNA gene (V3-V4) was sequenced using the Illumina Miseq platform. One-way ANOVA, Shannon diversity index, and Principal Coordinate Analysis (PCoA) were used to identify differences between and among samples. The exercise training group showed significant changes in the levels of Bacteroidetes, Proteobacteria, and Spirochaetes phyla (P<0.05), while there were no changes in the gut microbiota of the seasonal control group through the three months of the study (P>0.05). Moreover, with training two genera significantly changed in their relative abundance over time, namely Clostridium and Dysgonomonas (P<0.05). Dysgonomonas spp. was significantly changed in abundance during the exercise training period (P<0.05). Also Treponema spp. showed significant changes during the exercise training period (P<0.05). Shannon diversity index was decreased (P<0.05) in the exercise group at the beginning of the study, but then returned to pre-training levels. PCoA showed significant separation between time points of the exercise training group as far as the levels of genera and species (P<0.05) represented. Our results show that exercise training influences the gut microbiota, especially at the beginning of training.


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