The roles of environmental factors on reptile richness in Iran

2014 ◽  
Vol 35 (2) ◽  
pp. 215-225 ◽  
Author(s):  
Mahboubeh Sadat Hosseinzadeh ◽  
Mansour Aliabadian ◽  
Eskandar Rastegar-Pouyani ◽  
Nasrullah Rastegar-Pouyani
Keyword(s):  
Species Richness ◽  
Environmental Factors ◽  
Biodiversity Hotspot ◽  
Spatial Analyses ◽  
Iranian Plateau ◽  
Distribution Maps ◽  
Richness Patterns ◽  
Southwest Of Iran ◽  
Zoogeographical Region ◽  
Reptilian Species

Iran is usually considered as a bridge between Oriental and African zoogeographical region, and also the 20th global biodiversity hotspot. Herpetofauna of the Iranian Plateau has a high diversity compared to other areas in the region and has always been interesting for herpetologists in terms of biogeography, ecology and zoogeography. In this study, distribution maps of 215 terrestrial reptilian species (of which 50 were endemic to Iran) were digitized and the species richness patterns were correlated with 13 environmental factors using spatial analyses methods. Our results showed that the hotspot regions for all reptilian species are concentrated on south and southwest of Iran. This result is consistent with the Irano-Anatolian biodiversity hotspot. Based on spatial analyses, species richness in the area is affected by seven environmental variables which are associated with temperature and probably interpreted as the most important factor on reptile richness in Iran.

scholarly journals Low predictive power of mid-domain effect to explain geographic species richness patterns in Palearctic songbirds

2007 ◽  
Vol 76 (3) ◽  
pp. 197-204 ◽  
Author(s):  
M. Aliabadian ◽  
C. S. Roselaar ◽  
R. Sluys ◽  
V. Nijman
Keyword(s):  
Species Richness ◽  
Predictive Power ◽  
Explanatory Power ◽  
Null Model ◽  
Species Range ◽  
Geometric Constraints ◽  
Diversity Patterns ◽  
Distribution Maps ◽  
Biogeographic Patterns ◽  
Richness Patterns

In the study of diversity patterns, the Mid-domain effect (MDE), which explains gradients in diversity solely on the basis of geometric constraints, has emerged as a null-model against which other hypotheses can be tested. The effectiveness, measured by its predictive power, of these MDE models appears to depend on the size of the study area and the range-sizes of the taxa considered. Here we test the predictive power of MDE on the species richness patterns of birds and assess its effectiveness for a variety of species range sizes. We digitised distribution maps of 889 species of songbird endemic to the Palearctic, and analysed the emergent biogeographic patterns with WORLDMAP software. MDE had a predictive power of 20% when all songbirds were included. Major hotspots were located south of the area where MDE predicted the highest species-richness, and some of the observed coldspots were in the centre of the Palearctic, contradicting the predictions of the MDE. MDE had little explanatory power (3-19%) for all but the largest range sizes, whereas MDE performed equal or better for the large-ranged species (20-34%) compared to the overall model. Overall MDE did not accurate explain species-richness patterns in Palearctic songbirds. Subsets of larger-range species did not always have a larger predictive power than smaller-range species or the overall model. Despite their low predictive power, MDE models can have a role to play in explaining biogeographic patterns but other variables need to be included in the model as well.

scholarly journals Palaeo-precipitation is a major determinant of palm species richness patterns across Madagascar: a tropical biodiversity hotspot

2013 ◽  
Vol 280 (1757) ◽  
pp. 20123048 ◽  
Author(s):  
Mijoro Rakotoarinivo ◽  
Anne Blach-Overgaard ◽  
William J. Baker ◽  
John Dransfield ◽  
Justin Moat ◽  
...  
Keyword(s):  
Species Richness ◽  
Biodiversity Hotspot ◽  
Major Determinant ◽  
Tropical Biodiversity ◽  
Palm Species ◽  
Richness Patterns

Effects of environmental factors on species richness patterns of herb layer in Eastern Zhongtiao Mountain

2005 ◽  
Vol 16 (3) ◽  
pp. 175-180
Author(s):  
Liu Qiu-feng ◽  
Kang Mu-yi ◽  
Wang Hao ◽  
Liu Quan-ru
Keyword(s):  
Species Richness ◽  
Environmental Factors ◽  
Herb Layer ◽  
Richness Patterns

scholarly journals The Effect of Climate and Human Pressures on Functional Diversity and Species Richness Patterns of Amphibians, Reptiles and Mammals in Europe

Diversity ◽  
2021 ◽  
Vol 13 (6) ◽  
pp. 275
Author(s):  
Mariana A. Tsianou ◽  
Maria Lazarina ◽  
Danai-Eleni Michailidou ◽  
Aristi Andrikou-Charitidou ◽  
Stefanos P. Sgardelis ◽  
...  
Keyword(s):  
Species Richness ◽  
Functional Diversity ◽  
Agricultural Land ◽  
Influential Factor ◽  
Climatic Variables ◽  
Quadratic Entropy ◽  
Functional Richness ◽  
Precipitation Seasonality ◽  
Rao’S Quadratic Entropy ◽  
Richness Patterns

The ongoing biodiversity crisis reinforces the urgent need to unravel diversity patterns and the underlying processes shaping them. Although taxonomic diversity has been extensively studied and is considered the common currency, simultaneously conserving other facets of diversity (e.g., functional diversity) is critical to ensure ecosystem functioning and the provision of ecosystem services. Here, we explored the effect of key climatic factors (temperature, precipitation, temperature seasonality, and precipitation seasonality) and factors reflecting human pressures (agricultural land, urban land, land-cover diversity, and human population density) on the functional diversity (functional richness and Rao’s quadratic entropy) and species richness of amphibians (68 species), reptiles (107 species), and mammals (176 species) in Europe. We explored the relationship between different predictors and diversity metrics using generalized additive mixed model analysis, to capture non-linear relationships and to account for spatial autocorrelation. We found that at this broad continental spatial scale, climatic variables exerted a significant effect on the functional diversity and species richness of all taxa. On the other hand, variables reflecting human pressures contributed significantly in the models even though their explanatory power was lower compared to climatic variables. In most cases, functional richness and Rao’s quadratic entropy responded similarly to climate and human pressures. In conclusion, climate is the most influential factor in shaping both the functional diversity and species richness patterns of amphibians, reptiles, and mammals in Europe. However, incorporating factors reflecting human pressures complementary to climate could be conducive to us understanding the drivers of functional diversity and richness patterns.

scholarly journals Arthropod community structure in pastures of an island archipelago (Azores): looking for local–regional species richness patterns at fine-scales

2004 ◽  
Vol 94 (2) ◽  
pp. 111-121 ◽  
Author(s):  
P.A.V. Borges ◽  
V.K. Brown
Keyword(s):  
Species Richness ◽  
Regional Scale ◽  
Local Scale ◽  
Local Species Richness ◽  
Β Diversity ◽  
Arthropod Species ◽  
Α Diversity ◽  
Local Species ◽  
Richness Patterns

AbstractThe arthropod species richness of pastures in three Azorean islands was used to examine the relationship between local and regional species richness over two years. Two groups of arthropods, spiders and sucking insects, representing two functionally different but common groups of pasture invertebrates were investigated. The local–regional species richness relationship was assessed over relatively fine scales: quadrats (= local scale) and within pastures (= regional scale). Mean plot species richness was used as a measure of local species richness (= α diversity) and regional species richness was estimated at the pasture level (= γ diversity) with the ‘first-order-Jackknife’ estimator. Three related issues were addressed: (i) the role of estimated regional species richness and variables operating at the local scale (vegetation structure and diversity) in determining local species richness; (ii) quantification of the relative contributions of α and β diversity to regional diversity using additive partitioning; and (iii) the occurrence of consistent patterns in different years by analysing independently between-year data. Species assemblages of spiders were saturated at the local scale (similar local species richness and increasing β-diversity in richer regions) and were more dependent on vegetational structure than regional species richness. Sucking insect herbivores, by contrast, exhibited a linear relationship between local and regional species richness, consistent with the proportional sampling model. The patterns were consistent between years. These results imply that for spiders local processes are important, with assemblages in a particular patch being constrained by habitat structure. In contrast, for sucking insects, local processes may be insignificant in structuring communities.

Sign in / Sign up

Export Citation Format

Share Document