Contrasting water, dry matter and air contents distinguish orthophylls, sclerophylls and succophylls (leaf succulents)

Differences in leaf texture (hardness, thickness) distinguish orthophylls (soft leaves), sclerophylls (hard leaves) and (semi)succophylls (water-storing leaves). Texture is controlled by dry matter, water and air contents. Our aim was to a) identify the best index of succulence, b) assess how these three components vary with leaf type, and c) derive bounds for these properties among the four main leaf-texture classes. Eight contrasting species from the Namib Desert, South Africa were assessed for their leaf area (A), thickness (z), dry mass (D), saturated water content (Q), and relative volume of dry matter, water and air to derive various indices of leaf texture. Q/A (= QV•z), where QV is saturated water storage per unit volume of leaf, is an ideal index of succulence. Specific leaf area (SLA) is more suitable as an index of hardness (SLA-1 = D/A) but only among non-succulents. Rising leaf specific gravity among sclero-orthophylls is due to replacement of air by dry matter but water am..., Fieldwork
Leaves were collected from eight species growing wild at Groenriviersond, 500 km north of Cape Town, South Africa (30º 51' S, 17º 34' E). The species were selected to cover the full range of textures among perennials at the study site [specific leaf area (SLA) ranged from 2 to 20 mm2 mg-1, Lamont and Lamont 2000]. They were Pteronia onobromoides (Asteraceae, shrub to 50 cm tall, hard-leaved), Salvia lanceolata (Lamiaceae, shrub to 1 m tall, soft-leaved), Eriocephalus africanus (Asteraceae, shrub to 1 m tall, soft-leaved), Stoeberia utilis (Aizoaceae, syn. Mesembryanthemaceae, ground creeper, succulent), Ruschia fugitans (Aizoacae, syn. Mesembryanthemaceae, ground creeper, large-leaved succulent), Zygophyllum morgsana (Zygophyllaceae, shrub to 50 cm, semi-succulent), Othonna cylindrica (Asteraceae, shrub to 40 cm, succulent) and Senecio aff. sarcoides (Asteraceae, undershrub, small-leaved succulent). Nomenclature is as given in Eccles et al. (1999) and, from hereon, only the ge..., , # Data from: Contrasting water, dry matter and air contents distinguish orthophylls, sclerophylls and succophylls (leaf succulents)

[https://doi.org/10.5061/dryad.ksn02v7g5](https://doi.org/10.5061/dryad.ksn02v7g5)

## Description of the data and file structure

*Fieldwork*

Leaves were collected from eight species growing wild at Groenriviersond, 500 km north of Cape Town, South Africa (30º 51' S, 17º 34' E). The species were selected to cover the full range of textures among perennials at the study site [specific leaf area (SLA) ranged from 2 to 20 mm2 mg-1, Lamont and Lamont 2000]. They were *Pteronia onobromoides* (Asteraceae, shrub to 50 cm tall, hard-leaved), *Salvia lanceolata* (Lamiaceae, shrub to 1 m tall, soft-leaved), *Eriocephalus africanus* (Asteraceae, shrub to 1 m tall, soft-leaved), *Stoeberia utilis* (Aizoaceae, syn. Mesembryanthemaceae, ground creeper, succulent), *Ruschia fugitans* (Aizoacae, syn. Mesembryanthemaceae, ground creeper, large-leaved succulent), *Zygophy...,