Imperial College London

DrJamesRosindell

Faculty of Natural SciencesDepartment of Life Sciences (Silwood Park)

Senior Research Fellow
 
 
 
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Contact

 

+44 (0)20 7594 2242j.rosindell

 
 
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Location

 

W1.5KennedySilwood Park

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Summary

 

Publications

Citation

BibTex format

@article{Rosindell:2012,
author = {Rosindell, J and Jansen, PA and Etienne, RS},
journal = {Journal of Plant Ecology},
pages = {64--71},
title = {Age structure in neutral theory resolves inconsistencies related to reproductive-size threshold},
volume = {5},
year = {2012}
}

RIS format (EndNote, RefMan)

TY  - JOUR
AB - AimsNeutral theory consists of a suite of models that assume ecological equivalence among individual organisms. They have been most commonly applied to tropical forest tree communities either as null models or as approximations. Neutral models typically only include reproductive adults; therefore, fitting to empirical tree community data requires defining a reproductive-size threshold, which for trees is usually set arbitrarily to a diameter at breast height (DBH) of 100 mm. The inevitable exclusion of some reproductive adults and inclusion of some saplings cause a non-random sampling bias in neutral model fits. Here, we investigate this problem and resolve it by introducing simple age structure into a neutral model.MethodsWe compared the performance and sensitivity of DBH threshold of three variants of a spatially explicit neutral model: the traditional model, a model incorporating random sampling and a model with two distinct age classes—reproductive adults and saplings. In the age-structured model, saplings are offspring from adults that disperse according to a Gaussian dispersal kernel around the adults. The only extra parameter is the ratio of adults to saplings, which is not a free parameter but directly measurable. We used species–area relation- ships (SARs) to explore the predicted effect of saplings on the species richness at different scales in our model. We then evaluated the three model variations to find the parameters required to maintain the ob- served level of species richness in the 50-ha plot on Barro Colorado Island (BCI). We repeated our analysis filtering the data at differentINTRODUCTIONNeutral theory refers to a collection of neutral models each as- suming ecological equivalence between individuals (Bellminimum tree-size thresholds in order to find the effect this threshold has on our results. Lastly, we used empirical species–individual rela- tionships (SIRs) to test the pre-existing hypothesis that environmental filtering i
AU - Rosindell,J
AU - Jansen,PA
AU - Etienne,RS
EP - 71
PY - 2012///
SP - 64
TI - Age structure in neutral theory resolves inconsistencies related to reproductive-size threshold
T2 - Journal of Plant Ecology
VL - 5
ER -