scholarly journals Diatom Species Richness in Algal Flora of Pamir, Tajikistan

2018 ◽  
Vol 14 (3) ◽  
pp. 301 ◽  
Author(s):  
Toirbek Niyatbekov ◽  
Sophia Barinova

The main objective of this study was to quantify the diatom floral richness and analyze the diversity structure in Pamir aquatic habitats. We revealed 455 species (552 with infraspecific taxa) of diatom algae compiled from reference studies in 1930-1983 that was done for the first time, and our data after many floristic surveys conducted in the field during 2000-2015. Floristic analysis of the total species richness revealed 65 rare and 22 species new for Pamir algal flora, and has allowed us to identify prevailed Classes, Orders, and Families in the diatoms. Only four genera are prevailing and contain about 30% of total richness. The Pinnularia species from them are representing extremely large numbers (39). They prefer fresh, clear, circumneutral-water habitats in natural aquatic objects with developed phytoperiphytonic communities, included many rare species and can be peculiarities of the Pamir diatom flora.

ZooKeys ◽  
2018 ◽  
Vol 741 ◽  
pp. 219-254 ◽  
Author(s):  
Pavel S. Nefediev ◽  
Gyulli Sh. Farzalieva ◽  
Ivan H. Tuf ◽  
Khozhiakbar Kh. Nedoev ◽  
Saparmurad T. Niyazov

The total species richness in the myriapod assemblages of the lowland Altais near Charyshskoe Village, Altai Province, southwestern Siberia, Russia is estimated to be at least 19 species from ten genera, eight families, five orders, and two classes. The following species are new to SW Siberia: Lithobius (Ezembius) ostiacorum Stuxberg, 1876,L. vagabundusStuxberg, 1876, and L. (Monotarsobius) nordenskioeldii Stuxberg, 1876, while L. (E.) proximus Sseliwanoff, 1880 and L. (M.) insolens Dányi & Tuf, 2012 are recorded for the first time from the Altai Province of Russia. A species ofStrigamiawhich is morphologically similar to Strigamia cf. transsilvanica (Verhoeff, 1928) has been found in the study area but its true specific identity is yet to be determined. The seasonal dynamics of myriapod assemblages in terms of the species diversity, density, sex-age structure, and vertical distribution along the soil profile have been studied with regard to the different slope exposures.


2008 ◽  
Vol 38 (7) ◽  
pp. 1807-1816 ◽  
Author(s):  
Björn Nordén ◽  
Frank Götmark ◽  
Martin Ryberg ◽  
Heidi Paltto ◽  
Johan Allmér

Partial cutting is increasingly applied in European temperate oak-dominated forests for biofuel harvesting, and to counteract succession in protected stands. Effects on biodiversity of these measures need to be carefully evaluated, and species-rich but neglected taxa such as fungi should be considered. We studied the effects of partial cutting on fungal fruiting bodies on woody debris. In 21 closed canopy forests rich in large oaks in Sweden, on average 25%–30% of the basal area was cut. Fruiting bodies were counted and some were collected in treated and control plots before and after treatment. We found 334 basidiomycete and 47 ascomycete species. Species richness of basidiomycetes declined significantly more in treated plots (on average 26%) than in control plots (on average 13%) between seasons. Species richness of ascomycetes increased by 17% in control plots and decreased by 2% in treated plots. Total species richness was significantly reduced on fine woody debris (1–10 cm in diameter), but not on coarse woody debris (>10 cm). Overall species composition did not change significantly as a result of partial cutting, but red-listed species tended to decrease more in treated plots. We suggest that approximately 30% of the stands should not be thinned, and dead stems and fallen branches should not be removed, to favor saproxylic fungi and their associated fauna.


2007 ◽  
Vol 50 (6) ◽  
pp. 1033-1042 ◽  
Author(s):  
Yzel Rondon Súarez ◽  
Sabrina Bigatão Valério ◽  
Karina Keyla Tondado ◽  
Alexandro Cezar Florentino ◽  
Thiago Rota Alves Felipe ◽  
...  

The influence of spatial, temporal and environmental factors on fish species diversity in headwater streams in Paraguay and Paraná basins, Brazil was examined. A total of 4,605 individuals were sampled, distributed in 60 species. The sampled streams in Paraná basin presented a larger total species richness (42) than Paraguay streams (40). However the estimated richness was larger in Paraguay basin (53) than Paraná streams (50). The streams of Paraná basin had a greater mean species richness and evenness, while more individuals per sample were found in the Paraguay basin. Difference between the sub-basins were found in the Paraguay basin, while for the basin of Paraná, richness and evenness vary significantly between the sub-basins, but the number of individuals varied seasonally. The most important environmental factors to species diversity and abundance were altitude, water temperature, stream width and stream depth for both the basins.


2020 ◽  
Vol 10 (1) ◽  
Author(s):  
Tanya A. Petruff ◽  
Joseph R. McMillan ◽  
John J. Shepard ◽  
Theodore G. Andreadis ◽  
Philip M. Armstrong

Abstract Historical declines in multiple insect taxa have been documented across the globe in relation to landscape-level changes in land use and climate. However, declines have either not been universally observed in all regions or examined for all species. Because mosquitoes are insects of public health importance, we analyzed a longitudinal mosquito surveillance data set from Connecticut (CT), United States (U.S.) from 2001 to 2019 to identify changes in mosquito community composition over time. We first analyzed annual site-level collections and metrics of mosquito community composition with generalized linear/additive mixed effects models; we also examined annual species-level collections using the same tools. We then examined correlations between statewide collections and weather variables as well as site-level collections and land cover classifications. We found evidence that the average trap night collection of mosquitoes has increased by ~ 60% and statewide species richness has increased by ~ 10% since 2001. Total species richness was highest in the southern portion of CT, likely due to the northward range expansion of multiple species within the Aedes, Anopheles, Culex, and Psorophora genera. How the expansion of mosquito populations in the northeast U.S. will alter mosquito-borne pathogen transmission in the region will require further investigation.


Hacquetia ◽  
2015 ◽  
Vol 14 (2) ◽  
pp. 307-318 ◽  
Author(s):  
Evagelos Baliousis

Abstract The floristic investigation of the Ionian island of Kalamos resulted in the addition of 275 specific and infraspecific taxa, which are reported here, to a present total of 502 taxa. For each newly recorded taxon local distribution and habitat types are presented. Convolvulus pentapetaloides and Malcolmia graeca subsp. hydraea are reported for the first time from the Ionian islands. Some of the new records concern rare taxa in Greece or regional endemics, which are, therefore, chorologically significant, such as Alkanna corcyrensis, Stachys ionica, Heptaptera colladonioides. A brief description of some of the vegetation types of the island is given. The results of floristic analysis and phytogeographical aspects demonstrate the pronounced Mediterranean character of the island’s flora.


2007 ◽  
Vol 144 (3) ◽  
pp. 465-486 ◽  
Author(s):  
CHRISTOPHER J. CLEAL

The South Wales Coalfield has the most complete Westphalian macrofloral record anywhere on the Variscan Foreland or adjacent basins, with 135 biodiversity-meaningful morphospecies having been recognized. All of the standard macrofloral biozones of the Westphalian Stage have been recognized, although a detailed comparison with the Central Pennines Coalfields has indicated some discrepancies in the relative positions of the biozonal boundaries. Total Species Richness progressively increases through the Langsettian Substage, and then remains relatively stable through most of the Duckmantian and Bolsovian substages. There is a distinct reduction in Total Species Richness towards the top of the Bolsovian Substage, but this partially recovers in the middle Asturian Substage with the appearance of a range of marattialean ferns, and medullosalean and callistophytaleans pteridosperms. There is no evidence of any significant drop in Total Species Richness towards the top of the succession, indicating that conditions at this time were relatively stable. The change from coastal floodplain to alluvial braidplain conditions in middle Bolsovian times correlates with a marked increase in the proportion of medullosalean remains being preserved in the adpression record, reflecting an expansion of the clastic-substrate habitats.


2019 ◽  
Vol 88 (1) ◽  
pp. 42-53 ◽  
Author(s):  
Bernhard A. Huber ◽  
Anne Chao

Ratio-like approaches for estimating global species richness have been criticised for their unjustified extrapolation from regional to global patterns. Here we explore the use of cumulative percentages of ‘new’ (i.e., not formally described) species over large geographic areas (‘megatransects’) as a means to overcome this problem. In addition, we take into account undetected species and illustrate these combined methods by applying them to a family of spiders (Pholcidae) that currently contains some 1,700 described species. The raw global cumulative percentage of new species (‘new’ as of the end of 2008, when 1,001 species were formally described) is 75.1%, and is relatively constant across large biogeographic regions. Undetected species are estimated using the Chao2 estimator based on species incidence data (date by species and locality by species matrices). The estimated percentage of new species based on the date by species matrices is 76.0% with an estimated standard error (s.e.) of 2.6%. This leads to an estimated global species richness of about 4,200 with a 95% confidence interval of (3,300, 5,000). The corresponding values based on locality by species matrices are 84.2% (s.e. 3.0%) and 6,300 with a 95% confidence interval of (4,000, 8,600). Our results suggest that the currently known 1,700 species of Pholcidae may represent no more than about 25–40% of the total species richness. The impact of further biasing factors like geography, species size and distribution, cryptic species, and model assumptions needs to be explored.


Author(s):  
Konstantinos Tsiamis ◽  
Akira F. Peters ◽  
Dawn M. Shewring ◽  
Aldo O. Asensi ◽  
Pieter Van West ◽  
...  

This paper provides a comprehensive checklist of the marine benthic macroalgal flora of Ascension Island (tropical South Atlantic Ocean), based on both new collections and previous literature. 82 marine macroalgae were identified from our work, including 18 green algae (Ulvophyceae), 15 brown algae (Phaeophyceae) and 49 red algae (Rhodophyta). Among our collections, 38 species and infraspecific taxa are reported for the first time from Ascension Island, including seven green, three brown and 28 red macroalgae, raising the total number of seaweeds recorded in Ascension so far to 112 taxa in species and infraspecific level. No seagrasses have been recorded at Ascension Island.


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