Study of catenal separation in the herbaceous layer of South African Savanna subtypes.

This dataset provides a comprehensive inventory of herbaceous plant community composition and absolute density along topographic (catenal) gradients in the South African savanna. Data were collected across three distinct reserves representing diverse ecological zones: Letlapa Pula Game Reserve (LPGR; Central Bushveld bioregion), Selati Game Reserve (SGR; Mopane bioregion), and Kempiana Nature Reserve (KNR; Lowveld bioregion). The study utilized a nested hierarchical sampling design to quantify the distribution of grasses and forbs across three primary terrain units: Crest, Midslope, and Footslope. In each reserve, 90 plots of 2 x 2 m were surveyed (30 plots per terrain unit, nested within 40 x 40 m quadrats), resulting in a total of 270 sampling units. The dataset includes counts of individual plants per species (108 species in LPGR, 93 species in SGR, and 74 species in KNR). The dataset is organized into three CSV files, one for each study area, containing: 1. Bioregion and Site Identifiers: Locating the data within the South African National Biodiversity Institute (SANBI) framework. 2. Topographic Context: Classification by catenal position (Crest, Midslope, Footslope). 3. Species Abundance Matrix: Absolute density counts of all identified herbaceous species. This data is intended to support research into catenal separation, environmental filtering, beta diversity, and the functional role of the herbaceous layer in savanna ecosystem resilience. It provides a baseline for understanding how local topography and regional climatic factors interact to shape plant community structure.