Diversity of waterbirds wintering in Douz wetlands (south Tunisia): factors affecting wetland occupancy and species richness

2018 ◽  
Vol 33 (5) ◽  
pp. 917-925 ◽  
Author(s):  
Foued Hamza ◽  
Slaheddine Selmi
Keyword(s):  
Species Richness ◽  
Factors Affecting ◽  
South Tunisia

Factors affecting species richness and beta diversity of vascular plants on small islands in the Wenzhou region of eastern China

2017 ◽  
Vol 37 (2) ◽  
Author(s):  
王金旺 WANG Jinwang ◽  
魏馨 WEI Xin ◽  
陈秋夏 CHEN Qiuxia ◽  
李效文 LI Xiaowen ◽  
杨升 YANG Sheng
Keyword(s):  
Species Richness ◽  
Beta Diversity ◽  
Vascular Plants ◽  
Eastern China ◽  
Small Islands ◽  
Factors Affecting

scholarly journals Algae in sphagnum epiphyton from the mires of the Subpolar Urals

2017 ◽  
Vol 23 (1) ◽  
pp. 3-16
Author(s):  
Irina Sterlyagova ◽  
Julia Shabalina
Keyword(s):  
Species Richness ◽  
Species Diversity ◽  
Sea Level ◽  
High Abundance ◽  
Algal Communities ◽  
Factors Affecting ◽  
Subpolar Urals ◽  
Main Factors

Abstract Species diversity of algal communities of sphagnum epiphyton was studied in six mountain and plain mires of the Subpolar Urals (Russia). A total of 154 species and intraspecific taxa from six divisions were identified. The highest species richness was recorded for Bacillariophyta (96 taxa) and Charophyta (33) divisions. Species Kobayasiella parasubtilissima, Tabellaria flocculosa and Eunotia lunaris had high abundance. Dominant communities were often formed by Eunotia lunaris, E. mucophila, Kobayasiella parasubtilissima and Pinnularia subcapitata. CCA analysis showed that conductivity and altitude above the sea level are the main factors affecting the development of algae in the studied mires.

Effects of Water Transported Sediment on Corticolous Lichen Communities

1986 ◽  
Vol 18 (4) ◽  
pp. 339-347 ◽  
Author(s):  
S. L. Beckelhimer ◽  
T. E. Weaks
Keyword(s):  
Water Quality ◽  
Spatial Distribution ◽  
Species Richness ◽  
Physical Factors ◽  
Ohio River ◽  
Small Stream ◽  
Factors Affecting ◽  
Multivariate Technique ◽  
Lichen Community ◽  
Heavy Loads

AbstractThe spatial distribution of corticolous lichens was studied along Big Seven Mile Creek (Cabell County, West Virginia, U.S.A.), a small stream that was periodically inundated by floodwaters carrying heavy loads of sediment. Lichen communities located at 0, 1.0 and 1.5 km from the confluence with the Ohio River were compared using step-wise discriminant analysis, a multivariate technique. Of the physical factors tested, the results indicated that the sediment on the tree boles was the most important factor separating the three stations and bole heights. Species richness was established to be an important mensurational variable separating stations, bole heights, and parallel and perpendicular transects. Changes observed in lichen community structure are assumed to have resulted from microclimatic variation brought about primarily by sedimentation associated with flooding. Failure of the physical factors and biotic variables to separate tree bole aspects (faces of boles in respect to the stream) indicate that abrasion and current-induced exfoliation are not important factors affecting lichen communities in the study area. Corticolous lichens occurring along streams subject to periodic inundation may represent a useful indicator in studies of flooding, water quality, and/or sedimentation in watersheds.

Factors affecting species richness of marine elasmobranchs

2013 ◽  
Vol 22 (8) ◽  
pp. 1703-1714 ◽  
Author(s):  
Cástor Guisande ◽  
Bernardo Patti ◽  
Antonio Vaamonde ◽  
Ana Manjarrés-Hernández ◽  
Patricia Pelayo-Villamil ◽  
...  
Keyword(s):  
Species Richness ◽  
Factors Affecting

Blackfly (Diptera, Simuliidae) communities and species richness estimation in Carpathian montane streams

2013 ◽  
Vol 8 (7) ◽  
pp. 681-692 ◽  
Author(s):  
Andrej Štangler ◽  
Jozef Halgoš ◽  
Pavel Beracko
Keyword(s):  
Species Richness ◽  
Environmental Factors ◽  
Species Composition ◽  
Flow Speed ◽  
Factors Affecting ◽  
Typical Species ◽  
Species Richness Estimation ◽  
West Carpathians ◽  
Montane Streams ◽  
First Time

AbstractThe present work gives the result of blackfly fauna research of the Slovenský raj (West Carpathians, Slovakia). Our aim was to describe the composition of blackfly communities, find indicator species for communities, describe environmental factors affecting communities and determine the potential changes in species richness. Research was carried out in 2007 and 2008. The presence of 22 species of blackflies was confirmed at 20 sites in the area of Slovenský raj. 12 species were recorded for the first time in this area. The potential for further increase in diversity was calculated by a nonparametric estimation of species richness. Two main groups of sites with their typical blackflies communities were indentified using a TWINSPAN analysis. The presence of Simulium ornatum, S. variegatum and S. argyreatum was typical in larger streams in broad valleys. The absence or low abundance of these species was typical for smaller streams in canyons. Based on the species composition of blackflies communities, we identified 6 groups of sites: 1. anthropogenically disturbed submountain rivers (typical species: Simulium ornatum, S. reptans, S. equinum), 2. undisturbed metarhithral (typical species: Simulium bertrandi, S. codreanui, S. costatum, S. vernum, S. argenteostriatum, S. degrangei, S. argyreatum, S. variegatum), 3. undisturbed hyporhithral (typical species: Simulium trifasciatum, S. tuberosum), 4. undisturbed epirhithral (typical species: Prosimulium hirtipes, P. rufipes), 5. hypocrenal (typical species: Simulium cryophilum, S. monticola) and 6. anthropogenically disturbed epirhithral (typical species: Simulium brevidens, S. maximum). The most important environmental factors explaining differences in species composition like altitude, flow speed, pH, conductivity, oxygen saturation, sulphates concentration and presence of riparian vegetation were identified by the CCA analysis.

Sign in / Sign up

Export Citation Format

Share Document