303 species, each with at. least 1 stem. In 1990.

Richness = the number of species. Evenness or relative abundance = extent to which numbers of individuals of different species are equal or skewed. Speciation generates new species and adds to species richness. Extinction reduces species richness.

Generally exclude accidental species in the count. Does not take into account abundance patterns among the various species. Species counts depend on the sample size or sample area (rarely do you get every one!) Equilibrium model of island biogeography (MacArthur & Wilson, 1967) # of species (species richness) on an island is determined by immigration and emigration of species. Larger islands and islands closer to mainland will have greater species richness.

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SPECIES ABUNDANCE, DIVERSITY, RICHNESS STUDIES: BIBLIOGRAPHY

1. Volterra, Vito. “Fluctuations in the abundance of a species considered mathematically.” (1926): 558.  Dynamics of predator species and prey species are used to develop a nonlinear model for the interpretation of specie abundance data. Full text pdf provided.
2. Colautti, Robert I., Igor A. Grigorovich, and Hugh J. MacIsaac. “Propagule pressure: a null model for biological invasions.” Biological Invasions 8.5 (2006): 1023-1037.  Invasion ecology must explain the ability of species to establish in, spread to, or become abundant in novel communities and the susceptibility of habitats to the establishment or proliferation of invaders. Abundant invaders generally occupy similar habitats as native species, while abundant species tend to be less affected by enemies. Germination success and reproductive output are significantly positively associated with invasiveness when results from both stages were combined. We also found that propagule pressure was a significant predictor of both invasiveness and conclude that propagule pressure should serve as the basis of a null model for studies of biological invasions when inferring process from patterns of invasion.
3. Brown, James H., David W. Mehlman, and George C. Stevens. “Spatial variation in abundance.” Ecology 76.7 (1995): 2028-2043. The abundance of bird species varies in a systematic way over the geographic range, exhibiting positive spatial autocorrelation at small distances and a tendency to increase from the edges toward the center of the range. The magnitude and pattern of spatial variation in local population density has important implications for basic ecology and biogeography, especially for the dynamics and regulation of abundance on both space and time, the limits and internal structure of the geographic range, and the interspecific variation in abundance observed within local communities.
4. Yoccoz, Nigel G., James D. Nichols, and Thierry Boulinier. “Monitoring of biological diversity in space and time.” Trends in ecology & evolution 16.8 (2001): 446-453.  Monitoring programmes are being used increasingly to assess spatial and temporal trends of biological diversity, with an emphasis on evaluating the efficiency of management policies. Recent reviews of the existing programmes, with a focus on their design in particular, have highlighted the main weaknesses: the lack of well-articulated objectives and the neglect of different sources of error in the estimation of biological diversity. We review recent developments in methods and designs that aim to integrate sources of error to provide unbiased estimates of change in biological diversity and to suggest the potential causes.
5. Connor, Edward F., and Earl D. McCoy. “The statistics and biology of the species-area relationship.” The American Naturalist 113.6 (1979): 791-833. 
6. Lawton, John H. “Range, population abundance and conservation.” Trends in ecology & evolution 8.11 (1993): 409-413. Several patterns in the distribution and abundance of organisms have now been documented. They include broad (but not universal) positive correlations between range sizes and population abundances; a decline in the proportion of sites occupied and in average population densities from the centre to the edge of a species’ range, with either unimodal or multimodal peaks of abundance and occupancy in the core of the range; and intriguing, but still poorly documented phylogenetic effects on both range size and abundance. All these patterns require further work to establish their generality, and all of them lack generally agreed explanations. They are important, however, not only theoretically but also practically, because of the constraints and opportunities they appear to provide for the management and conservation of species.
7. Roberts, Callum M., and Rupert FG Ormond. “Habitat complexity and coral reef fish diversity and abundance on Red Sea fringing reefs.” Marine Ecology Progress Series (1987): 1-8.
8. Gascon, Claude, et al. “Matrix habitat and species richness in tropical forest remnants.” Biological conservation 91.2-3 (1999): 223-229. The abilities of species to use the matrix of modified habitats surrounding forest fragments may affect their vulnerability in fragmented landscapes. We used long-term (up to 19-year) studies of four animal groups in central Amazonia to test whether species’ abundances in the matrix were correlated with their relative extinction proneness in forest fragments. The four groups, birds, frogs, small mammals, and ants, had varying overall responses to fragmentation: species richness of small mammals and frogs increased after fragment isolation, whereas that of birds and ants decreased. For all four groups, a high proportion of nominally primary-forest species were detected in matrix habitats, with 8–25% of species in each group found exclusively in the matrix. The three vertebrate groups (birds, small mammals, frogs) exhibited positive and significant correlations between matrix abundance and vulnerability to fragmentation, suggesting that species that avoid the matrix tend to decline or disappear in fragments, while those that tolerate or exploit the matrix often remain stable or increase. These results highlight the importance of the matrix in the dynamics and composition of vertebrate communities in tropical forest remnants, and have important implications for the management of fragmented landscapes.

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Species Abundance Biology in the Climate Change era  

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