Dark diversity reveals importance of biotic resources and competition for plant diversity across habitats

TY - JOUR

T1 - Dark diversity reveals importance of biotic resources and competition for plant diversity across habitats

AU - Fløjgaard, Camilla

AU - Valdez, Jose W.

AU - Dalby, Lars

AU - Moeslund, Jesper Erenskjold

AU - Clausen, Kevin K.

AU - Ejrnæs, Rasmus

AU - Pärtel, Meelis

AU - Brunbjerg, Ane Kirstine

N1 - © 2020 The Authors. Ecology and Evolution published by John Wiley & Sons Ltd.

PY - 2020/6/1

Y1 - 2020/6/1

N2 - Species richness is the most commonly used metric to quantify biodiversity. However, examining dark diversity, the group of missing species which can potentially inhabit a site, can provide a more thorough understanding of the processes influencing observed biodiversity and help evaluate the restoration potential of local habitats. So far, dark diversity has mainly been studied for specific habitats or large-scale landscapes, while less attention has been given to variation across broad environmental gradients or as a result of local conditions and biotic interactions. In this study, we investigate the importance of local environmental conditions in determining dark diversity and observed richness in plant communities across broad environmental gradients. Using the ecospace concept, we investigate how these biodiversity measures relate to abiotic gradients (defined as position), availability of biotic resources (defined as expansion), spatiotemporal extent of habitats (defined as continuity), and species interactions through competition. Position variables were important for both observed diversity and dark diversity, some with quadratic relationships, for example, plant richness showing a unimodal response to soil fertility corresponding to the intermediate productivity hypothesis. Interspecific competition represented by community mean Grime C had a negative effect on plant species richness. Besides position-related variables, organic carbon was the most important variable for dark diversity, indicating that in late-succession habitats such as forests and shrubs, dark diversity is generally low. The importance of highly competitive species indicates that intermediate disturbance, such as grazing, may facilitate higher species richness and lower dark diversity.

AB - Species richness is the most commonly used metric to quantify biodiversity. However, examining dark diversity, the group of missing species which can potentially inhabit a site, can provide a more thorough understanding of the processes influencing observed biodiversity and help evaluate the restoration potential of local habitats. So far, dark diversity has mainly been studied for specific habitats or large-scale landscapes, while less attention has been given to variation across broad environmental gradients or as a result of local conditions and biotic interactions. In this study, we investigate the importance of local environmental conditions in determining dark diversity and observed richness in plant communities across broad environmental gradients. Using the ecospace concept, we investigate how these biodiversity measures relate to abiotic gradients (defined as position), availability of biotic resources (defined as expansion), spatiotemporal extent of habitats (defined as continuity), and species interactions through competition. Position variables were important for both observed diversity and dark diversity, some with quadratic relationships, for example, plant richness showing a unimodal response to soil fertility corresponding to the intermediate productivity hypothesis. Interspecific competition represented by community mean Grime C had a negative effect on plant species richness. Besides position-related variables, organic carbon was the most important variable for dark diversity, indicating that in late-succession habitats such as forests and shrubs, dark diversity is generally low. The importance of highly competitive species indicates that intermediate disturbance, such as grazing, may facilitate higher species richness and lower dark diversity.

KW - Beal's smoothing

KW - community completeness

KW - conservation

KW - regional species pool

KW - species co-occurrence

KW - vascular plants

KW - COMMUNITY COMPLETENESS

KW - SPECIES RICHNESS

KW - POOLS

KW - BIODIVERSITY

KW - VEGETATION

KW - ESTABLISHMENT

KW - CONSERVATION

KW - PATTERNS

KW - FORESTS

UR - http://www.scopus.com/inward/record.url?scp=85085927075&partnerID=8YFLogxK

U2 - 10.1101/685040

DO - 10.1101/685040

M3 - Journal article

C2 - 32607214

SN - 2045-7758

VL - 10

SP - 6078

EP - 6088

JO - Ecology and Evolution

JF - Ecology and Evolution

IS - 12

ER -