Species abundance distribution pattern of microarthropod communities in SW Canada

It is still unclear whether simple niche-derived or neutrality-derived statistical models is better to quantify the experimental species-abundance distribution pattern (sad) for microarthropod communities. in the present study,by utilizing the sampling diversity data of three microarthropod taxonomic groups (oribatids,collembolans and mesostigmatids),my objectives are to test and compare five alternative statistical models for fitting empirical microarthropod sad curves,including neutral,zipf,broken stick,niche preemption and geometric models. fitting power of the models were evaluated using x2 test,kolmogorov-smirnov (ks) test and akaike information criterion (aic). my results showed that,for the sad of the whole microarthropod community and mesostigmatid group,zipf model is the best model identified by aic criteria. for oribatid and collembolan sad curves,geometric model is the most favored one. however,all the models yielded significant difference between the expected and observed sad patterns over different taxonomic groups,as indicated by both ?2 and k-s tests. thus,either neutral and niche models could explain sad patterns of microarthropod communities perfectly. in summary,the synergy of different mechanisms and the development of hybrid models and the proper transformation might be of some helps to remove the observed significant difference for microarthropod communities. copyright 2014 zoological society of pakistan.