The iterative process of plant species inventorying for obtaining reliable biodiversity patterns

Abstract

We require representative data of species occurrence to explain plant diversity patterns, but most of the available information is incomplete and biased. To improve our knowledge, we suggest that species inventorying should be an iterative process encompassing the following: (1) the detection of taxonomic and geographical gaps; (2) the planning of a survey design to reduce such gaps; and (3) the evaluation of field sampling results. Here, we focus on the latter phase for the bryophytes of Terceira Island (Azores) for which we have previously estimated < 1% of the area as well surveyed based on historical collections. To examine the performance of our stratified survey based on two factors (land use and environmental regions), we used rarefaction curves, ANOVA tests and bootstrap sampling. We recorded 40% of all the species known for the island and presented eight new citations. The species assemblages remained similar between historical and current inventories. Most localities had completeness values > 85%, but we always exceeded the optimal sampling effort. Land uses and environmental regions affected species diversity, but, unexpectedly, to a different degree. Our study illustrates the difficulties of planning field surveys to obtain reliable biodiversity patterns, even when prior information and standardized sampling protocols are explicitly considered. © 2015 The Linnean Society of London, Botanical Journal of the Linnean Society, 2015, 177, 491–503.

Assessing spatial and temporal biases and gaps in the publicly available distributional information of Iberian mosses

“…The extent of the Wallacean shortfall varies considerably amongst taxonomic groups ( Amano et al 2016 , Troia and McManamay 2016 ), depending on the historical interest on the survey or study of each one of them. While the study of diversity patterns at large scales has been mainly focused on vascular plants and vertebrates ( Mutke and Barthlott 2005 , Aranda et al 2015 ), bryophytes have been considered just on a few occasions ( Mutke and Geffert 2010 , Geffert et al 2013 , Hespanhol et al 2015 , Mateo et al 2016 , Berdugo et al 2018 ). Therefore, although the knowledge on this highly-diverse group of organisms has been developed over a long historical period ( Magill 2010 ), especially in Europe ( Mutke and Geffert 2010 ), the quality of moss distributional data has been scarcely assessed ( Callaghan and Ashton 2008 , Mutke and Geffert 2010 , Aranda et al 2011 , Meyer et al 2016 ).…”