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- Insect conservation on islandsPublication . Gerlach, Justin; Borges, Paulo A. V.; Fattorini, Simone; Porch, Nick; Wilkins, Vicky
- Protected areas and insect conservationPublication . Fattorini, Simone; Dapporto, Leonardo; Borges, Paulo A. V.
- Species and trait abundance distributions as tools for understanding disturbance effects and community assembly in applied ecologyPublication . Ulrich, Werner; Borges, P.A.V.; Fattorini, Simone; ter Steege, Hans; Gotelli, Nicholas; Magurran, Anne; Marquet, Pablo; Schrader, Julian; Matthews, Thomas; Gutierrez, JesusABSTRACT: Species abundance distributions (SADs) depict the order of species based on their ranked abundances. While they have been central to much theoretical work in community ecology, their practical value in applied ecology is still debated. Supported by a meta-analysis of 1153 publications on SADs, we review the state of the art in the practical use of SADs and provide a conceptual framework for the study of SADs in an applied context. Of the studies sourced through the meta-analysis, only 5% had a truly applied focus; 93% of these studies dealt with the influence of agricultural practices, forest management, pollution or other forms of disturbance on the shape of the SAD. We found little support for previous claims that disturbance shifts species abundance distributions from a lognormal to a steep logseries form. Some species-rich communities, such as tropical forests, are well fit by a logseries even in the absence of disturbance, and steep, uneven SADs may be more representative of dispersal-limited communities under neutral dynamics. Policy implications. Further insight into the links between disturbance and species abundance may come from the recognition that the species abundance distribution (SAD) is a special case of a broader concept, the trait abundance distribution (TAD), which can provide indirect information on resource utilisation and niche partitioning. An analysis of the changes in SADs and TADs, together with environmental data, should allow for a better understanding of the assembly and functioning of ecological communities in both applied and basic ecology.
- Use of cover data to model species abundance distributions through continuous probability functionsPublication . Moradi, Halime; Prado, Paulo; Oldeland, Jens; Borges, P.A.V.; Fattorini, SimoneABSTRACT: Species abundance distribution (SAD) models describe the abundances of the species within ecological communities. SAD modelling has been developed using frequency distributions that require the use of count data (number of individuals). However, many organisms, such as most plants, cannot be counted. Instead, abundance is estimated using cover values. We show here how SAD approaches conceived for modelling frequency distributions based on counts can be modified to deal with continuous distributions and provide an application using relative plant cover as a continuous measure of abundance. We applied several SAD models using continuous probability functions to investigate how plant SADs changed along a wide (2,500 m) elevational gradient in the Alborz Mountains (Iran). We found that most communities were adequately fitted by the Weibull distribution, whose parameters changed along the gradient in response to the interplay between biotic and environmental filtering processes. The use of continuous probability functions in SAD modelling should be encouraged in research dealing with plant communities and other organisms for which counting individuals is theoretically or practically impossible.