# Diaspore Surface Structure

## Summary

DIASPORE SURFACE STRUCTURE is a dimensionless index that describes the smoothness of a diaspore's surface based on images of the diaspores, i.e. in two dimensions. It ranges from 0 to 1 with 0 indicating rough and 1 indicating smooth diaspore surfaces.

## Trait description

DIASPORE SURFACE STRUCTURE (column code: DIA_SURFACESTRUCTURE) is a dimensionless index that describes the smoothness of a diaspore's surface based on images of the diaspores, i.e. in two dimensions. The index ranges from 0 (rough surface) to 1 (smooth surface). It is calculated as the quotient of the perimeter of the smallest convex hull polygon around the diaspore and the perimeter of the diaspore (Fig. 1).

If more than one measurement was available, generally only the mean value is presented. Raw data are available on request.

Fig. 1. DIASPORE SURFACE STRUCTURE for one diaspore of dandelion (*Taraxacum *Sect. *Ruderalia*). DIASPORE SURFACE STRUCTURE is the quotient of the perimeter of the smallest convex hull polygon around the diaspore (in blue) and the perimeter of the diaspore (in red).

## Data sources

DIASPORE SURFACE STRUCTURE is calculated from digital images of the diaspores. Most images were made with an AZ-100 loupe (Nikon, Tokyo, Japan) and camera-type DS-Fi, 5.07 megapixel (Nikon, Tokyo, Japan). Image analysis was performed with NIS-Elements (Nikon, Tokyo, Japan).

## Literature

Römermann, C. et al. (2005): How to predict attachment potential of seeds to sheep and cattle coat from simple morphological seed traits. Oikos 110, 219-230.

Will, H., Maussner, S. & Tackenberg, O. (2007): Experimental studies of diaspore attachment to animal coats: Predicting epizoochorous dispersal potential. Oecologia 153, 331-339.