Pollen and plant diversity relationships in a Mediterranean montane area

Matthew A Adeleye,Rufus B Akindola,W O Van Der Knaap,Simon E Connor,Jacqueline F N Van Leeuwen,Michela Mariani

doi:10.1007/s00334-020-00811-0

Abstract

Understanding the significance of pollen diversity is key to reconstructing plant diversity over long timescales. Here we present quantitative pollen-plant diversity comparisons for a mountainous area of the Western Mediterranean region. Samples were collected between 430–1,865 m elevation and pollen-plant diversity assessed through richness and turnover (beta-diversity) metrics. We found statistically significant relationships between pollen diversity metrics and the diversity of pollen-equivalent plant taxa in the surrounding vegetation. The strongest richness relationships emerged from the exclusion of trees and with standardisation of the sample size (rarefaction) applied to both plant and pollen datasets. Three different metrics for turnover produced similar results, but emphasise different components of beta diversity (replacement vs richness differences). These results pave the way for reconstructing biodiversity trends from pollen sequences, with a number of caveats. Fossil pollen is a potentially rich source of information on past biodiversity in the Mediterranean region.

Highlights

IntroductionBiodiversity is unevenly distributed, with the greatest diversity in equatorial regions and the least at high latitudes (Kreft & Jetz 2007; Kraft et al 2011; Jenkins et al 2013)
Biodiversity is key to the stability, functioning and productivity of ecosystems (Cardinale et al 2012).On a global scale, biodiversity is unevenly distributed, with the greatest diversity in equatorial regions and the least at high latitudes (Kreft & Jetz 2007; Kraft et al 2011; Jenkins et al 2013)
We present pollen and floristic data from the Western Mediterranean to test the following null hypotheses: 1) there is no relationship between plant richness and pollen richness in the study area and 2) there is no relationship between plant community turnover and pollen turnover in the study area

Summary

Introduction

Biodiversity is unevenly distributed, with the greatest diversity in equatorial regions and the least at high latitudes (Kreft & Jetz 2007; Kraft et al 2011; Jenkins et al 2013). This global biodiversity gradient is linked to resource availability, competition and the history of past climatic changes (Mittelbach et al 2007; Rabosky and Hurlbert 2015; Grace et al 2016). In floristically and culturally rich regions, such as the Mediterranean, mitigation of biodiversity loss can only be achieved when we understand the drivers and long-term trajectories of biodiversity change (Willis et al 2010)

Objectives

Methods

Results

Discussion

Conclusion