Indicators of species richness at the local scale in an alpine region: a comparative approach between plant and invertebrate taxa

2009 ◽  
Vol 19 (5) ◽  
pp. 1341-1352 ◽  
Author(s):  
Oliver-D. Finch ◽  
Jörg Löffler
Keyword(s):  
Species Richness ◽  
Local Scale ◽  
Alpine Region ◽  
Comparative Approach

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.

scholarly journals Testing biodiversity theory using species richness of reef-building corals across a depth gradient

2019 ◽  
Vol 15 (10) ◽  
pp. 20190493 ◽  
Author(s):  
T. Edward Roberts ◽  
Sally A. Keith ◽  
Carsten Rahbek ◽  
Tom C. L. Bridge ◽  
M. Julian Caley ◽  
...  
Keyword(s):  
Species Richness ◽  
Large Scale ◽  
Coral Species ◽  
Environmental Gradients ◽  
Abiotic Factors ◽  
Empirical Support ◽  
Null Model ◽  
Local Scale ◽  
Small Scale ◽  
Energy Availability

Natural environmental gradients encompass systematic variation in abiotic factors that can be exploited to test competing explanations of biodiversity patterns. The species–energy (SE) hypothesis attempts to explain species richness gradients as a function of energy availability. However, limited empirical support for SE is often attributed to idiosyncratic, local-scale processes distorting the underlying SE relationship. Meanwhile, studies are also often confounded by factors such as sampling biases, dispersal boundaries and unclear definitions of energy availability. Here, we used spatially structured observations of 8460 colonies of photo-symbiotic reef-building corals and a null-model to test whether energy can explain observed coral species richness over depth. Species richness was left-skewed, hump-shaped and unrelated to energy availability. While local-scale processes were evident, their influence on species richness was insufficient to reconcile observations with model predictions. Therefore, energy availability, either in isolation or in combination with local deterministic processes, was unable to explain coral species richness across depth. Our results demonstrate that local-scale processes do not necessarily explain deviations in species richness from theoretical models, and that the use of idiosyncratic small-scale factors to explain large-scale ecological patterns requires the utmost caution.

scholarly journals A global model of island species–area relationships

2019 ◽  
Vol 116 (25) ◽  
pp. 12337-12342 ◽  
Author(s):  
Thomas J. Matthews ◽  
François Rigal ◽  
Kostas A. Triantis ◽  
Robert J. Whittaker
Keyword(s):  
Species Richness ◽  
Structural Equation ◽  
Negative Relationship ◽  
Equation Model ◽  
Local Scale ◽  
Ecological Process ◽  
Global Pattern ◽  
Island Species ◽  
Species Area ◽  
Globally Distributed

The increase in species richness with island area (ISAR) is a well-established global pattern, commonly described by the power model, the parameters of which are hypothesized to vary with system isolation and to be indicative of ecological process regimes. We tested a structural equation model of ISAR parameter variation as a function of taxon, isolation, and archipelago configuration, using a globally distributed dataset of 151 ISARs encompassing a range of taxa and archipelago types. The resulting models revealed a negative relationship between ISAR intercept and slope as a function of archipelago species richness, in turn shaped by taxon differences and by the amount and disposition of archipelago area. These results suggest that local-scale (intra-archipelago) processes have a substantial role in determining ISAR form, obscuring the diversity patterns predicted by island theory as a function of archipelago isolation. These findings have implications for the use and interpretation of ISARs as a tool within biogeography, ecology, and conservation.

Diving behavior reduces genera richness of lice (Insecta, Phthiraptera) of mammals

2007 ◽  
Vol 52 (1) ◽  
Author(s):  
Bernadett Felső ◽  
Lajos Rózsa
Keyword(s):  
Species Richness ◽  
Body Mass ◽  
Comparative Approach ◽  
Diving Behavior ◽  
Taxonomic Richness ◽  
Entire Life ◽  
Confounding Variables ◽  
The Mean ◽  
The Difference ◽  
Aquatic Mammals

AbstractLice of mammals spend the entire life cycle in the host hair, thus, the microclimate found near the mammal skin is likely to influence the structure of louse communities. Here we use a comparative approach to examine the effect of mammals’ diving behavior on the taxonomic richness of their lice. We compared the mean genera richness of lice, and — as potential confounding variables — the mean species richness of host, and the mean body mass of host between diving clades and their non-diving sister clades. Louse genera richness was significantly lower in clades of aquatic mammals than on their non-diving sister clades. Host species richness was not significantly different between these clades. Body mass was significantly higher in clades of aquatic mammals, however, the direction of this difference cannot explain the difference in parasite taxonomic richness. This study suggests that mammals’ diving behavior can effectively shape their ectoparasite communities.

Patterns of sponge distribution in Cagarras Archipelago, Rio de Janeiro, Brazil

2004 ◽  
Vol 84 (4) ◽  
pp. 681-687 ◽  
Author(s):  
Leandro C. Monteiro ◽  
Guilherme Muricy
Keyword(s):  
Cluster Analysis ◽  
Species Richness ◽  
Quantitative Data ◽  
Rio De Janeiro ◽  
Qualitative Data ◽  
Scuba Diving ◽  
Local Scale ◽  
Wave Action ◽  
Vertical Walls ◽  
The City

The structure and distribution of the sponge community in five sites and four habitats in Cagarras Archipelago, Rio de Janeiro, Brazil, are described. The archipelago has three major islands (Cagarra, Palmas, and Comprida), and four islets. Qualitative samples were taken by SCUBA diving in the three islands and in two islets, and quantitative samples were taken in Palmas Island only. Cluster analysis using Jaccard's coefficient on qualitative data grouped the two islets (Cagarra Bank and Cagarra Islet), which are more exposed to wave action, and the three islands formed a group of relatively sheltered sites. Cluster analysis using Bray–Curtis coefficient on quantitative data from different habitats in Palmas Island allowed distinction of three groups of samples: overhangs, shallow horizontal surfaces (6 m depth), and vertical walls plus deeper horizontal surfaces (17 m depth). Sponge abundance was greater in overhangs (61·2 ind m−2), which were dominated by Protosuberites sp. and Clathrina conifera. Abundance was reduced in vertical walls (31·1 ind m−2) and deep horizontal surfaces (16·8 ind m−2). Pachychalina sp. dominated the deep horizontal surfaces and Clathrina conifera was dominant in overhangs. Values of Shannon's diversity in overhangs, vertical walls (both with H′=2·1 bits ind−1) and deep horizontal surfaces (H′=1·7 bits ind−1) were moderate and similar, whereas in shallow horizontal surfaces the sponges were both less diverse (H′=0·37) and less abundant (8·5 ind m−2). Shallow horizontal surfaces were dominated by Hymeniacidon heliophila. The reduced species richness of the sponge community in Cagarras Archipelago when compared with other sites in Brazil and elsewhere is probably due in part to the pollution from the city of Rio de Janeiro. Wave action appears to reduce the number of sponge species at a local scale, whereas substrate inclination affects more strongly the species composition and abundance than the diversity of sponges.

Sign in / Sign up

Export Citation Format

Share Document