The age of the Tashinga Formation (Karoo Supergroup) in the Mid-Zambezi Basin, Zimbabwe and the first phytosaur from mainland sub-Saharan Africa
Paul M. BarrettLara SciscioPia A. VigliettiTimothy J. BroderickCelina A. SuarezGlenn R. SharmanAndrew S. JonesDarlington MunyikwaSteve F. EdwardsKimberley E. J. ChapelleKathleen N. DollmanMichel ZondoJonah N. Choiniere
22
Citation
79
Reference
10
Related Paper
Citation Trend
Keywords:
Mainland
Biome
Biome
Settlement (finance)
Cite
Citations (0)
Biomes are large-scale biotic communities (ecosystems) distinguished by specific ecological functionality and evolutionary origins. They can be studied and delimited using functional variables but also using physiognomic and vegetation-textural surrogates. Biomes are spatially explicit units, and as such, they can be seen as complexes of biotic communities at various hierarchical levels, including zonobiomes, global biomes, continental biomes, and regional biomes. Each of these categories has its characteristic own set of ecological drivers. Walter's zonobiome system is possibly the most common biome system coined to explain the diversity of large-scale biotic communities on Earth. It is a bioclimatic approach, recognising the role of climatic factors driving the zonal biome patterns at large scales. It also provides for biomes driven by other factors, such as soils and hydrology, called azonal biomes. This chapter aims to revisit the usefulness of the zonal/azonal conceptual framework in the ocean-dominated Southern Hemisphere. It puts significant emphasis (at the large-scale biome levels) on the climato-genetic drivers, modern tools of bioclimatology, and sources of bioclimatic data. By doing so, this chapter is also a prelude to the formulation of a new zonobiome system, serving as a basis for a Global Hierarchical Biome System.
Biome
Cite
Citations (0)
Biome conservatism is often regarded as common in diversifying lineages, based on the detection of low biome shift rates or high phylogenetic signal. However, many studies testing biome conservatism utilise a single-biome-per-species approach, which may influence the detection of biome conservatism. Meta-analyses show that biome shift rates are significantly lower (less than a tenth), when single biome occupancy approaches are adopted. Using New Zealand plant lineages, estimated biome shifts were also significantly lower (14–67% fewer biome shifts) when analysed under the assumption of a single biome per species. Although a single biome approach consistently resulted in lower biome shifts, it detected fewer instances of biome conservatism. A third of clades (3 out of 9) changed status in biome conservatism tests between single and multiple biome occupancy approaches, with more instances of significant biome conservatism when using a multiple biome occupancy approach. A single biome approach may change the likelihood of finding biome conservatism because it assumes biome specialisation within species, falsely recognises some biome shift types and fails to include other biome shift types. Our results indicate that the degree of biome fidelity assumed has a strong influence on analyses assessing biome shift rates, and biome conservatism testing. We advocate analyses that allow species to occupy multiple biomes.
Biome
Conservatism
Occupancy
Cite
Citations (6)
Biome
Environmental change
Global Change
Cite
Citations (2)
Biome
Cite
Citations (10)
Abstract Aim Recent studies in southern Africa identified past biome stability as an important predictor of biodiversity. We aimed to assess the extent to which past biome stability predicts present global biodiversity patterns, and the extent to which projected climatic changes may lead to eventual biome changes in areas with constant past biome. Location Global. Taxon Spermatophyta; terrestrial vertebrates. Methods Biome constancy was assessed and mapped using results from 89 dynamic global vegetation model simulations, driven by outputs of palaeoclimate experiments spanning the past 140 ka. We tested the hypothesis that terrestrial vertebrate diversity is predicted by biome constancy. We also simulated potential future vegetation, and hence potential future biome patterns, and quantified and mapped the extent of projected eventual future biome change in areas of past constant biome. Results Approximately 11% of global ice‐free land had a constant biome since 140 ka. Apart from areas of constant Desert, many areas with constant biome support high species diversity. All terrestrial vertebrate groups show a strong positive relationship between biome constancy and vertebrate diversity in areas of greater diversity, but no relationship in less diverse areas. Climatic change projected by 2100 commits 46%–66% of global ice‐free land, and 34%–52% of areas of past constant biome (excluding areas of constant Desert) to eventual biome change. Main conclusions Past biome stability strongly predicts vertebrate diversity in areas of higher diversity. Future climatic changes will lead to biome changes in many areas of past constant biome, with profound implications for biodiversity conservation. Some projected biome changes will result in substantial reductions in biospheric carbon sequestration and other ecosystem services.
Biome
Global biodiversity
Cite
Citations (16)
Biome
Cite
Citations (89)
The file contains BIOME 6000 reconstructions of vegetation at 0, 6, and 21ka at individual sites, where the original published nomenclature for individual regions has been converted to a globally-applicable standardized classification (BIOME 6000 Consolidated Name). Two other standardized classifications are also given: common biome names between BIOME 6000 and the BIOME 4.2 model (BIOME 4.2 BIOME 6000 common names) and the megabiome scheme used by Harrison and Bartlein (2012) (MegaBiome Scheme 2). Additional information to translate BIOME 4.2 outputs into either BIOME 6000 Consolidated Names or BIOME 4.2 BIOME 6000 common names is also given.
Biome
Cite
Citations (42)
Biomes are important constructs for organizing understanding of how the worlds' major terrestrial ecosystems differ from one another and for monitoring change in these ecosystems. Yet existing biome classification schemes have been criticized for being overly subjective and for explicitly or implicitly invoking climate. We propose a new biome map and classification scheme that uses information on (i) an index of vegetation productivity, (ii) whether the minimum of vegetation activity is in the driest or coldest part of the year, and (iii) vegetation height. Although biomes produced on the basis of this classification show a strong spatial coherence, they show little congruence with existing biome classification schemes. Our biome map provides an alternative classification scheme for comparing the biogeochemical rates of terrestrial ecosystems. We use this new biome classification scheme to analyse the patterns of biome change observed over recent decades. Overall, 13% to 14% of analysed pixels shifted in biome state over the 30-year study period. A wide range of biome transitions were observed. For example, biomes with tall vegetation and minimum vegetation activity in the cold season shifted to higher productivity biome states. Biomes with short vegetation and low seasonality shifted to seasonally moisture-limited biome states. Our findings and method provide a new source of data for rigorously monitoring global vegetation change, analysing drivers of vegetation change and for benchmarking models of terrestrial ecosystem function.
Biome
Terrestrial ecosystem
Environmental change
Cite
Citations (77)
The knowledge of biomes as large-scale ecosystem units has benefited from advances in the ecological and evolutionary sciences. Despite this, a universal biome classification system that also allows a standardized nomenclature has not yet been achieved. We propose a comprehensive and hierarchical classification method and nomenclature to define biomes based on a set of bioclimatic variables and their corresponding vegetation structure and ecological functionality. This method uses three hierarchical biome levels: Zonal biome (Macrobiome), Biome and Regional biome. Biome nomenclature incorporates both bioclimatic and vegetation characterization (i.e. formation). Bioclimate characterization basically includes precipitation rate and thermicity. The description of plant formations encompasses vegetation structure, physiognomy and foliage phenology. Since the available systems tend to underestimate the complexity and diversity of tropical ecosystems, we have tested our approach in the biogeographical area of the Neotropics. Our proposal includes a bioclimatic characterization of the main 16 Neotropical plant formations identified. This method provides a framework that (1) enables biome distribution and changes to be projected from bioclimatic data; (2) allows all biomes to be named according to a globally standardized scheme; and (3) integrates various ecological biome approaches with the contributions of the European and North American vegetation classification systems. Taxonomic reference : Jørgensen et al. (2014). Dedication : This work is dedicated to the memory of and in homage to Prof. Dr. Salvador Rivas-Martínez.
Biome
Cite
Citations (8)