Species richness

About: Species richness is a research topic. Over the lifetime, 61672 publications have been published within this topic receiving 2183796 citations.

Structure and Dynamics

Abstract: This chapter analyzes the structure and dynamics of the tree community of Ogawa Forest Reserve (OFR).The main focus is on the relationships between species richness and size structure in local stands, and an explanation is proposed of how the high species richness of OFR is maintained (or how it might be lost). The study used the 1987 and 1997 census data of trees with a diameter at breast height (DBH) ≥ 5 cm (see Chapter 5). The 1987 data were used for the static analyses, and the data from both years were used for the analyses of community dynamics.

Habitat complexity and invertebrate species richness and abundance in tropical seagrass meadows

Abstract: Two potential measures of habitat complexity, plant species number and aboveground plant biomass, are considered in relation to the species richness and abundance of motile macroinvertebrates inhabiting tropical sea- grass (Thalassia testudinum (Konig)) meadows. Plant species number was not significantly related to either invertebrate species number or abundance and therefore does not appear to adequately represent habitat complexity for the invertebrate species being considered. However, aboveground plant biomass is significantly correlated with both invertebrate species number and abundance and appears to be a reasonable measure of habitat complexity for these species. A consideration of several alternative explanations for these results suggests that the significant correlation between aboveground plant biomass and inverte- brate species number probably results from the addition of cryptic species which inhabit protected habitats that are formed among the foliose branches of certain plant species when they are very dense. The significant aboveground plant biomass-invertebrate abundance correlation is most likely due to the protection from predators that thick vegetation provides, but may also be partly a result of the greater plant surface area that is available for habitation in heavily vegetated areas. The results of this first step toward quantifying relationships among plants and animals in seagrass meadows clearly indicate that experimental studies are needed to differentiate conclusively among the competing explanations which seek to explain community organization in seagrass meadows.

SESAM – a new framework integrating macroecological and species distribution models for predicting spatio‐temporal patterns of species assemblages

Abstract: Explaining the spatial and temporal distribution of biological diversity on Earth has been a research focus since the days of Alexander von Humboldt, Augustin Pyramus de Candolle, Alfred Russel Wallace and Charles Darwin, and it remains one of the major focuses in biogeography and macroecology Understanding the processes governing the distribution and assembly of biological communities has become a prerequisite for successfully predicting how the world will look in the wake of global environmental changes Currently, two distinct predictive spatial modelling approaches prevail (Ferrier & Guisan, 2006), which rely on two theoretical paradigms The first paradigm focuses directly on realized properties of species assemblages (eg Brown, 1995), such as richness, and the methods used include macroecological modelling (MEM; see Gotelli et al, 2009) The second paradigm focuses on aggregate properties of individual constituent species, used to reveal the properties of assemblages (eg Lortie et al, 2004; Ackerly & Cornwell, 2007) and applies species distribution modelling (SDM; see Guisan & Thuiller, 2005; Elith & Leathwick, 2009) to a spatial stack of species The properties of species assemblages include the number of co-occurring species (richness), inter-specifc abundance patterns, and compositional (eg community types), functional and structural characteristics Hereafter, all of our examples use species richness, the simplest measure of biodiversity and the most commonly considered property of species assemblages (Whittaker et al, 2001) In MEM, species richness is predicted directly, either based on theoretical expectations or from various factors thought to control the number of species able to coexist in a geographical unit (Fig 1, top) The main controlling factors are typically hypothesized to be available energy, environmental heterogeneity, disturbance or history, with scale effects and some level of stochasticity (Whittaker et al, 2001; Currie et al, 2004; Mittelbach et al, 2007; Field et al, 2009; Gotelli et al, 2009) The same approach can be used to model any other property of communities, although different hypotheses and explanatory variables are likely to apply to each property MEM is typically Department of Ecology and Evolution, University of Lausanne, Lausanne, Switzerland, Center for Macroecology, Evolution and Climate, University of Copenhagen, Copenhagen, Denmark

Recovery of Faunal Communities During Tropical Forest Regeneration

Abstract: As mature tropical forests are cleared, secondary forests may play an important role in the con- servation of animal species, depending on how fast animal communities recover during forest regeneration. I reviewed published studies on the recovery of animal species richness and composition during tropical forest regeneration. In 38 of the 39 data sets I examined, conversion of forest to agriculture or pasture substantially reduced species richness. Given suitable conditions for forest recovery, the species richness of the animal taxa considered can be predicted to resemble that of mature forests roughly 20-40 years after land abandonment. At least for ants and birds, however, recovery of species composition appears to take substantially longer than recovery of species richness. Because species richness for many taxa appears to recover relatively rapidly in secondary forests, conservation of secondary forests may be an effective investment in future diversity. The slower recovery of species composition indicates, however, that some species will require stands of mature forest to persist.