TITLE:
Bayesian Estimation of Shrubs Diversity in Rangelands under Two Management Systems in Northern Syria
AUTHORS:
Abdoul Aziz Niane, Murari Singh, Paul C. Struik
KEYWORDS:
Arid Rangelands; Species Abundance; Diversity; Shannon Index; Simpson Diversity Index; Bayesian Method
JOURNAL NAME:
Open Journal of Ecology,
Vol.4 No.4,
March
28,
2014
ABSTRACT:
The diversity of shrubs in rangelands of
northern Syria is affected by the grazing management systems restricted by the
increase in human and livestock populations. To describe and estimate diversity
and compare the rangeland grazing management treatments, two popular indices for
diversity, the Shannon index and the Simpson index, were studied for the four
combinations of two sites, Hammam and Obeisan, and two grazing methods, Closed
and Open, using frequentist and Bayesian approaches. We simulated the a priori and a-posteriori distributions of the Shannon and Simpson diversity
indices, where from a range of values for a constant in the a priori distribution the best value normalizing the distribution of the diversity
indices was chosen. The Bayesian diversity estimates were higher than their
frequentist counterparts and had lower standard errors. The grazing methods at
each site and sites under each grazing method delivered significant diversity
of shrub species. The Bayesian estimates resulted in lower p-values than the frequentist approach for two cases reflecting in Bayesian method’s higher power. Bayesian
approach is recommended as it has a wider framework for inference on diversity
studies.