Questioning Israel's Great Biodiversity—Relative to Whom? A Comment on Roll et al., 2009

2011 ◽  
Vol 57 (3) ◽  
pp. 183-192 ◽  
Author(s):  
Yoni Gavish
Keyword(s):  
Species Richness ◽  
Linear Regression ◽  
Unit Area ◽  
Biodiversity Hotspot ◽  
Biodiversity Hotspots ◽  
Species Area ◽  
C Value ◽  
Species Area Relationship ◽  
Z Value ◽  
Global Biodiversity

Each evolutionary-independent province has its own mainland species area relationship (SPAR). When using the power law SPAR (S = cAz), separate mainland SPARs are parallel in a log-log space (similar z value), yet they differ in species density per unit area (c value). This implies that there are two main SPAR-based strategies to identify biodiversity hotspots. The first treats all mainland SPARs of all provinces as if they form one global SPAR. This is the strategy employed by Roll et al. (2009) when questioning Israel's high biodiversity. They concluded that Israel is not a global biodiversity hotspot. Their results may arise from the fact that Israel's province, the Palaearctic, is relatively poor. Therefore, countries from richer provinces, whose mainland SPAR lies above the Palaearctic SPAR, are identified as global hotspots. The second strategy is to construct different mainland SPARs for each province and identify the provincial hotspots. In this manuscript I ask whether Israel's biodiversity is high relative to other countries within its province. For six different taxa, I analyzed data for Palaearctic countries. For each taxon, I conducted a linear regression of species richness against the country's area, both log transformed. The studentized residuals were used to explore Israel's rank relative to all other Palaearctic countries. I found that Israel lies above the 95th percentile for reptiles and mammals and above the 90th percentile for birds. Therefore, within the Palaearctic province, Israel is indeed a biodiversity hotspot.

Holy or Not, Israel is a Palaearctic Biodiversity Hotspot

2011 ◽  
Vol 57 (3) ◽  
pp. 207-211
Author(s):  
Yoni Gavish
Keyword(s):  
Species Richness ◽  
Species Turnover ◽  
Grid Cell ◽  
Biodiversity Hotspot ◽  
Statistical Prediction ◽  
Β Diversity ◽  
Α Diversity ◽  
Species Area ◽  
Prediction Limits ◽  
Global Biodiversity

In their rebuttal to my comment, Roll et al. (2011) defend their original conclusion, by questioning the theoretical framework on which I based my analysis. They stress the importance of the statistical prediction limits and the treatment of latitudinal location as a covariate. They also add an additional grid-cell-based analysis. Here, I claim that even if provincial species-area relationships (SPAR) are not parallel, they are still different. While relying on Roll et al.'s (2011) analyses, I show that for each taxon there is at least one other provincial SPAR that lies considerably above the Palaearctic SPAR, making Palaearctic countries less favorable to be identified as a global biodiversity hotspot. I further claim that prediction limits should not be used to answer the question in focus and that adding latitude as a covariate does not alter the results. Finally, I address the grid-cell analyses of Roll et al. (2011), claiming that Israel's diversity lies mainly in the species turnover between cells (i.e., β diversity) and not on the average species richness within cells (α diversity). Therefore I hold on to my former conclusion that at least for three taxa—birds, mammals, and reptiles—Israel is indeed a Palaearctic provincial hotspot.

scholarly journals The species-area-energy relationship in orchids

Lankesteriana ◽  
2015 ◽  
Vol 7 (1-2) ◽  
Author(s):  
Iva Schödelbauerová ◽  
Pavel Kindlmann ◽  
David Roberts
Keyword(s):  
Species Richness ◽  
Vegetation Index ◽  
Normalized Difference Vegetation Index ◽  
Unit Area ◽  
Relative Importance ◽  
Species Area ◽  
The Mean ◽  
Main Factors ◽  
Species Area Relationship ◽  
The Tropics

Area, energy available and latitude are the main factors influencing species richness: (1) species richness increases with area – the species-area relationship (SAR); (2) according to the species-energy rela- tionship (SER) the energy available to an assemblage (i.e. that which it can turn into biomass) at a particular spatial resolution influences the species richness; (3) there are more species per unit area in the tropics than in the temperate regions. To test the relative importance of area, energy available and latitude on species richness, we have collected data on species richness of orchids for various areas in the world and calculated the mean Normalized Difference Vegetation Index (NDVI) as a measure of energy availability in these areas. We show that area considered is always very important, and that latitude is more important than ener- gy available. 

Hot-Spot Facts and Artifacts-Questioning Israel's Great Biodiversity

2009 ◽  
Vol 55 (3) ◽  
pp. 263-279 ◽  
Author(s):  
Uri Roll ◽  
Lewi Stone ◽  
Shai Meiri
Keyword(s):  
Species Richness ◽  
Biological Diversity ◽  
Hot Spot ◽  
Flowering Plants ◽  
Prediction Intervals ◽  
Predicting Factors ◽  
Mediterranean Countries ◽  
Species Area ◽  
Expected Values ◽  
Species Area Relationship

Israel's biological diversity has been praised as being particularly rich in relation to its size; however this assumption was never tested when taking into account the empirical form of the species-area relationship. Here we compared the species richness of different countries to see if the Israeli diversity is exceptionally rich when area is accurately accounted for. We compared richness of amphibians, birds, mammals, reptiles, flowering plants, conifers and cycads, and ferns in all the world's countries. We further tested the effects of mean latitude, altitude span, and insularity on species richness both for all world countries and just for Mediterranean countries. For all taxa and in all tests, Israel lies within the prediction intervals of the models. Out of 42 tests, Israel's residuals lie in the upper decile of positive residuals once: for reptiles, when compared to all world countries, taking all predicting factors into account. Using only countries larger than 1000 km2, Israel was placed as top residual when compared to other Mediterranean countries for mammals and reptiles. We therefore conclude that Israel's species richness does not significantly exceed the expected values for a country its size. This is true when comparing it to either world or just Mediterranean countries. Adding more predicting factors does not change this fact.

Organisation de la richesse et de la composition floristiques d'îles de la Méditerranée occidentale (sud-est de la France)

1998 ◽  
Vol 76 (2) ◽  
pp. 321-331 ◽  
Author(s):  
Frédéric Médail ◽  
Éric Vidal
Keyword(s):  
Species Richness ◽  
Species Composition ◽  
Plant Species ◽  
Habitat Diversity ◽  
Mediterranean Islands ◽  
Plant Dispersal ◽  
Number Of Species ◽  
Continental Islands ◽  
Species Area ◽  
Species Area Relationship

The effects of physiographic variables (area, isolation, elevation, and substrate) and habitat diversity on plant species richness and composition have been investigated on some Mediterranean islands (southeastern France). The number of species - area relationship is significant but there are more diverse vegetation patterns on smallest islands (area smaller than 3.5 ha and, ultimately, 0.2 ha). Although the species composition is positively correlated to the distance from the continent, the effect of isolation is not so obvious because of the small distance of these continental islands from the continent. Some islands nearest to shore show very different plant species composition, suggesting a nonselective plant dispersal through some narrow stretches of sea. Habitat diversity represents one of the major explanatory factors of the species richness; nevertheless, it is not possible to settle between the two hypotheses effect of habitat diversity versus effect of area per se because of the correlation between the two factors. Key words: Mediterranean islands, insular biogeography, number of species - area relationship, isolation, habitat diversity, islets.

scholarly journals Wood ant assemblages of Formica rufa group on lake islands and in mainland woodland in Central Finland

2018 ◽  
Vol 29 (1) ◽  
pp. 21-29 ◽  
Author(s):  
Jouni Sorvari
Keyword(s):  
Species Richness ◽  
Occurrence Probability ◽  
Island Size ◽  
Formica Rufa ◽  
Wood Ants ◽  
Formica Rufa Group ◽  
Species Area ◽  
Island Community ◽  
Species Area Relationship ◽  
Formica Lugubris

Associations of island size and isolation on the occurrence and species richness of five wood ant species of the Formica rufa group (F. rufa, F. aquilonia, F. lugubris, F. polyctena and F. pratensis) was tested in the Lake Konnevesi archipelago in Central Finland. In addition, the species composition was compared to that of mainland forests of the same region. Island isolation had no associations with the wood ant occurrence in this archipelago, but for most species, increasing island size was positively associated with the occurrence probability. According to the findings among the five species, Formica lugubris is the best adapted for insular living. There was a positive species–area relationship as the species richness of wood ants increased with an increasing island size. The island community of wood ants was dominated by colonies of the monogynous (single queen) species whereas the mainland community was dominated by those of polygynous (multiple queen) species.

scholarly journals Correlation/causation in ecology: towards mechanistic explanations for the Species-Area Relationship

2016 ◽  
Author(s):  
Andersonn Prestes
Keyword(s):  
Species Richness ◽  
Positive Relationship ◽  
Abiotic Factors ◽  
Causal Explanations ◽  
Biotic And Abiotic Factors ◽  
Mechanistic Explanations ◽  
Species Area ◽  
Species Area Relationship ◽  
Per Se ◽  
Recurrent Patterns

There is a common intuition in biology that strict laws are very difficult to be found. Still, there are recurrent patterns in nature, suggesting broad generalizations and understanding of phenomena. The problem is that many generalizations in biology, especially in the form of correlations, might be decoupled from causality, weakening their power of explanation. Here, I bring an example on the Species-Area Relationship (SAR). The SAR is a well-known generalization in biology. The recurrent pattern states a positive relationship between area size and species richness. Understanding the mechanisms why there is a correlation between area and diversity remains a major challenge. I suggest an explicitly focus on mechanistic explanations for the SAR. I propose to use the integration, comparison and interpretation of other (associated or secondary) natural patterns in the searching for causal explanations. Area per se might not account for causality in species diversification or absolute species richness in larger regions. Biotic and abiotic factors of a given area might be studied in order to discover the causal underpinnings of the SAR.

Species and Generic Gamma-Scale Diversity in Shallow-Water Marine Amphipoda with Particular Reference to the Mediterranean

1996 ◽  
Vol 76 (1) ◽  
pp. 195-202 ◽  
Author(s):  
A.A. Myers
Keyword(s):  
Species Richness ◽  
Mediterranean Sea ◽  
Late Miocene ◽  
Evolutionary History ◽  
Amphipod Species ◽  
Species Area ◽  
Species Area Relationship ◽  
The Mediterranean ◽  
Shallow Seas

Major hotspots of amphipod species richness and of species and generic endemicity can be recognized in shallow seas. Recognition of ‘hotspots’ for amphipods must take account of the species-area relationship but not of latitude. The richness and endemicity of amphipods in the Mediterranean Sea is shown to be high when compared with other shallow seas This indicates a long in situ evolutionary history and is therefore not compatible with the hypothesis that the Mediterranean fauna was extirpated in the late Miocene.

scholarly journals Consequences of land-use change and the wildfire disaster of 2017 for the central Chilean biodiversity hotspot

2021 ◽  
Vol 21 (2) ◽  
Author(s):  
Andreas Ch. Braun ◽  
Fabian Faßnacht ◽  
Diego Valencia ◽  
Maximiliano Sepulveda
Keyword(s):  
Land Use ◽  
Species Richness ◽  
Land Use Change ◽  
Plant Species ◽  
Habitat Loss ◽  
Plant Species Richness ◽  
Biodiversity Hotspot ◽  
Anthropogenic Pressure ◽  
Biodiversity Hotspots ◽  
Central Chile

AbstractCentral Chile is an important biodiversity hotspot in Latin America. Biodiversity hotspots are characterised by a high number of endemic species cooccurring with a high level of anthropogenic pressure. In central Chile, the pressure is caused by land-use change, in which near-natural primary and secondary forests are replaced and fragmented by commercial pine and eucalyptus plantations. Large forest fires are another factor that can potentially endanger biodiversity. Usually, environmental hazards, such as wildfires, are part of the regular environmental dynamic and not considered a threat to biodiversity. Nonetheless, this situation may change if land-use change and altered wildfire regimes coerce. Land-use change pressure may destroy landscape integrity in terms of habitat loss and fragmentation, while wildfires may destroy the last remnants of native forests. This study aims to understand the joint effects of land-use change and a catastrophic wildfire on habitat loss and habitat fragmentation of local plant species richness hotspots in central Chile. To achieve this, we apply a combination of ecological fieldwork, remote sensing, and geoprocessing to estimate the spread and spatial patterns of biodiverse habitats under current and past land-use conditions and how these habitats were altered by land-use change and by a single large wildfire event. We show that land-use change has exceeded the wildfire’s impacts on diverse habitats. Despite the fact that the impact of the wildfire was comparably small here, wildfire may coerce with land-use change regarding pressure on biodiversity hotspots. Our findings can be used to develop restoration concepts, targeting on an increase of habitat diversity within currently fire-cleared areas and evaluate their benefits for plant species richness conservation.

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