Diversity and community structure of Ephemeroptera in freshwater stream of Megamalai hills, Tamil Nadu, India

ENTOMON ◽  
2021 ◽  
Vol 46 (4) ◽  
pp. 279-284
Author(s):  
S. Barathy ◽  
T. Sivaruban ◽  
Srinivasan Pandiarajan ◽  
Isack Rajasekaran ◽  
M. Bernath Rosi

In the study on the diversity and community structure of Ephemeroptera in the freshwater stream of Chinnasuruli falls on Megamalai hills, a total of 523 specimens belonging to thirteen genera and five families were collected in six month periods. Of the five families, Teloganodidae and Leptophlebiidae exhibited high diversity and Caenidae showed low diversity. Choroterpes alagarensis (Leptophlebiidae) is the most dominant species. Diversity indices such as Shannon and Simpson indices showed that diversity was maximum in November and December and it was minimum in August and January. Canonical Correspondence Analysis revealed that rainfall, water flow, turbidity, and air temperature were the major stressors in affecting the Ephemeropteran community structure.

Zoodiversity ◽  
2021 ◽  
Vol 55 (6) ◽  
pp. 451-458
Author(s):  
G. Kopij

The line transect method has been employed to assess species diversity, population densities and community structure of birds breeding in a mosaic of Kalahari Woodland and farmland, NE Namibia. The transect, 4.5 km long, was surveyed in 2014 and 2015. The total annual rainfall in 2014 was much higher than in 2015 (427 mm vs. 262 mm). In total, 40 breeding species in 2014, and 46 in 2015 were recorded. Six species were dominant in 2014 (Cape Turtle Dove, Laughing Dove, Emerald-spotted Dove, Blue Waxbill, and White-browed Scrub Robin) and only three species in 2015 (Cape Turtle Dove and Blue Waxbill and Yellow-fronted Canary). Although the cumulative dominance in 2014 almost doubled that in 2015, the Community Index in both years was almost identical. Also diversity indices and evenness index were very similar in both years compared. Granivorous birds were the most numerous feeding guild. Their contribution was similar in 2014 and 2015 (46.7 % vs. 43.4 %). Two other feeding guilds, insectivores and frugivores, comprised together more than 50 % in both years. The number of bird species and species diversity were not influenced by the differential rainfall. However, contrary to expectations, population densities of most bird species (at least the more numerous ones) were higher in the year with lower than in the year with higher rainfall. The number of species and species diversity was similar in the farmland and in neighbouring Kalahari Woodland in a pristine stage. However, population densities of most species were lower in the farmland than in the pristine woodland.


2017 ◽  
Vol 72 ◽  
pp. 545-552 ◽  
Author(s):  
Davi Butturi-Gomes ◽  
Miguel Petrere ◽  
Henrique C. Giacomini ◽  
Silvio Sandoval Zocchi

Author(s):  
M. Rajkumar ◽  
Jun Sun ◽  
I. R. Jenkinson ◽  
M.M. Rahman

A twelve-month investigation was undertaken on how copepod community structure varied in relation to environmental factors in the Coleroon estuary, south-east India. Sampling was monthly, from Station 1 in the sea to Station 4 in the Vettar backwaters. Canonical correspondence analysis (CCA) was applied to elucidate the environmental factors affecting the copepod community. A total of 104 copepod species in 38 genera and 26 families were recorded, with the Calanoids, Acartia erythraea and Oithona brevicornis being the most dominant. At all four stations, both these species loaded near the intercept of CCA axes 1 and 2, perhaps reflecting that they were autochthonous. Most species occurred in distinct seasonal patterns. Abundances ranged from 13 × 103 to 215 × 103 (ind. m−3). Coleroon waters showed high diversity (bits/ind.), from 5.29 at Station 3 to 4.97 at Station 4. Abundance correlated positively with temperature and salinity and negatively with rainfall, dissolved oxygen concentration (DO) and pH. Species diversity correlated strongly with abundance (P < 0.01). Abundance and diversity were highest during the summer, and both correlated positively with salinity. Temperatures (air and water), salinity, pH and DO varied in the ranges 26–36°C, 25–34.2°C, 9–38, 7.0–8.7 and 3.0–6.8 ml l-1, respectively. Nitrate, nitrite, phosphate and silicate (µM) varied in the ranges: 4.7–64.5, 0.4–14.1, 0.2–12.9 and 9.3–148, respectively.


Author(s):  
P.Y. Guo ◽  
H.T. Shen ◽  
J.H. Wang

This paper reports on the phytoplankton community, its composition, structure and distribution in Changjiang estuary from February 1999 to March 2000. Two hundred and eight species were identified in the dry and flood periods. Diatoms, with 143 species observed, was the most abundant phytoplankton group, accounting for 68.75% of the total phytoplankton species number. Skeletonema costatum was dominant among all the species. The phytoplankton of Changjiang estuary in China was divided into five ecological categories: freshwater species, estuary brackish water species, inshore low salinity species, inshore widespread species and off-sea high salinity species. During the dry period, the major phytoplankton populations in the surface layer were estuary inshore and offshore populations, distinguished from the composition of the bottom layer. The community structure was similar in the two layers during the flood period. The phytoplankton species diversity was calculated for Simpson, Shannon–Weaver diversity and evenness indices, and found to be higher in the dry period, due to the simple dominant species and low spatial heterogeneity in the flood period. Higher phytoplankton abundance was observed in the surface layer during the flood period. The phytoplankton species distribution, coinciding with the dominant species distribution, varied with salinity, and their abundance correlated significantly with nutrients and light.


2021 ◽  
Vol 886 (1) ◽  
pp. 012047
Author(s):  
A Achmad ◽  
U Damayanti ◽  
R I Maulany

Abstract Lower mountain forest in the complex of Mount Bulusaraung Bantimurung Bulusaraung National Park, is a one of bird’s habitat in the South Sulawesi. This area is a tourist destination, especially mountain climbing activities. Thus, it is necessary to know the diversity of animals, especially birds on this hiking trail, so that the information can be used to support ecotourism activities. This study aims to analyze the diversity of bird species in the complex of Bulusaraung Mountain, Bantimurung Bulusaraung National Park in order to support ecotourism activities. This research was conducted from April to June 2018. Data was collected using the line transect method on three lines, namely the Balleanging, Kattokaddaro and Tompobulu lines. The second and third paths are hiking trails, while the rest are trails leading to community agricultural areas. The geographical position of the transect line was recorded using GPS. The GIS method was used to generate a bird watching trail map. Data analysis was carried out to calculate the individual density and frequency of bird presence. In addition, the species diversity indices, species evenness indices, and species richness indices were also calculated. The results showed that there were 44 species of birds found in the study area, which were 16 species in the Balleanging line, 27 species in the Kattokaddaro line and 37 species in the Tompobulu line. The highest bird species diversity indices value was found on the Tompobulu line (H' = 2.93), while on the Kattokaddaro line it was H' = 2.73 and the Balleanging H' = 2.55. The results of this study will support the management strategy in Bantimurung Bulusaraung National Park in order to harmonize the conservation of biological resources through ecotourism activities that involve local communities to increase their economic income.


Author(s):  
Xianhua Xie ◽  
Yuanlin Ma ◽  
Zuguo Yu ◽  
Guosheng Han

Species diversity in microbiome is a cutting-edge concept in metagenomic research. In this study, we propose a multifractal analysis for metagenomic research. From the chaos game representation (CGR) visualization of simulated and real metagenomes, we find that there exists self-similarity in the visualization of metagenomes. Then we compute the multifractal dimensions for simulated and real metagenomes. For simulated metagenomes, we also compute their diversity indices, such as species richness indices, Shannon&rsquo;s diversity indices and Simpson&rsquo;s diversity indices respectively for varying value of . Fom the Pearson correlation coefficients between their multifractal dimensions and traditional species diversity indices, we find that the correlation coefficients between the multifractal dimensions and species richness indices and Shannon diversity indices reach their maximums at respectively. The correlation coefficients between the multifractal dimensions and Simpson&rsquo;s diversity indices reach their maximums at nearly. So the traditional diversity indices can be unified by the frame of multifractal analysis. These results coincided with the similar results in macrobial ecology. Finally, we apply our methods to real metagenomes of 100 infants&rsquo; gut microbiomes when they are newborn, 4 months and 12 months. Our results show that multifractal dimensions of infants&rsquo; gut microbiomes can discriminate the age difference.


1978 ◽  
Vol 29 (2) ◽  
pp. 141 ◽  
Author(s):  
GCB Poore ◽  
JD Kudenov

The distribution of soft-bottom macrobenthos in the Yarra River and Hobsons Bay, Vic.,is examined in terms of temporal changes in abundance and diversity, and related to selected environmental variables. Hierarchical classification was used to divide the stations into three zones: upstream river stations; downstream river stations with muddy bay stations; and sandy bay stations. The faunas of the river and the central muddy basin of Port Phillip Bay are similar although several common Bay species were absent in the river, probably as a result of competition and lowered salinity and dissolved oxygen. Faunal diversity of the Yarra River was lower than that of Hobsons Bay and is lower than that of equivalent areas in the northern hemisphere. Seasonality in species composition or diversity was not observed. The dominant river species, Theora fragilis (Bivalvia), was more abundant in the lower river than anywhere in Port Phillip Bay. Its life expectancy and density were lowest at stations further up the river. Species diversity seems more predictable in highly diverse communities lacking dominant species than in communities of low diversity dominated at all times by one or two species.


2015 ◽  
Vol 6 (1) ◽  
pp. 47 ◽  
Author(s):  
Suprapto Suprapto

Perairan Tarakan termasuk daerah penangkapan sumber daya ikan demersal dan udang cukup potensial di KalimantanUtara. Tingginya tingkat eksploitasi ikan demersal dengan menggunakan trawlmenyebabkan keragaman jenisnya rendah. Penelitian ikan demersal dilakukan di perairan Tarakan pada bulanMei,Agustus dan Nopember 2012. Tujuan penelitian adalah untuk memperoleh indeks keanekaragaman jenis ikan demersal. Data spesies ikan demersal dikumpulkan dari hasil tangkapan jaring trawl yang dioperasikan oleh kapal motor 20GT dengan metode sapuan area. Hasil penelitian menunjukkan bahwa jumlah taksa ikan demersal sebanyak 86 spesies yang tergolong kedalam45 famili. Komposisi jenis hasil tangkapan trawl didominasi oleh famili Leiognathidae (ikan petek), Sciaenidae (ikan gulama), Harpadontidae (ikan nomei),Apogonidae (ikan serinding) danMullidae (ikan bijinangka). Status keanekaragaman jenis termasuk dalamkategori sedang dengan indeks “Shanon-Wiener” (H’)berkisar antara 1,7-2,5 sedangkan indeks kekayaan “Margalef” (R1 ) berkisar antara 7-8. Penyebaran spesies ikan demersal bersifat sedang dengan indeks kemerataan jenis (E) rata-rata sebesra 0,5.Kelimpahan ikan demersal tidak ada yang dominan, ditunjukkan oleh nilai indeks kemerataan jenis “Pielou” (E) rata-rata sebesar 0,4.Tarakan and adjacent waters is one of potentially fishing ground of demersal fish resources in north Kalimantan. High exploitation by trawler tend to decreased of biodiversity of demersal fish in this area. Research has been conducted in the waters of Tarakan duringMay, August and November 2012. The aim of this research is to get species diversity indices of demersal fish, which is expected to be useful as one of the data capacity for sustainable fisheries management policy. Data obtained by using trawl fishing gear with a sweept area method.The results showed that demersal fish species richness 86 species, belonging to 45 families. Dominant family are Leiognathidae, Sciaenidae, Harpadontidae, Apogonidae andMullidae. Result of analysis indicate that species diversity in Tarakan waters in the medium category. Status of biodiversity consist of: range value diversityindices “Shanon-Wiener” (H’) was 1.7 to 2.5; species richness indices of “Margalef” (R1 ) are between 7-8; evenness indices of “Pielou” (E 1) was 0,5 and dominant indices “Pielou” (E) an average of 0.4.


Sign in / Sign up

Export Citation Format

Share Document