Potential geochemical constraints on Vachellia karroo seedlings immediately after germination in the Bedford Dry Grasslands of the Eastern Cape, South Africa

This dataset comprises soil chemistry data collected from the Bedford Dry Grasslands in the Eastern Cape, South Africa. The data focuses on the influence of soil nutrients on the encroachment of Vachellia karroo into previously treeless grasslands. Eighty composite soil samples (40 from encroached and 40 from non-encroached areas) were analysed for the following key nutrients: potassium (K), calcium (Ca), magnesium (Mg), sodium (Na), phosphorus (P), sulphur (S), manganese (Mn), copper (Cu), zinc (Zn), boron (B), organic carbon (C) and pH.

Soil samples were collected from the top 0-2 cm layer and processed using standard methods, including air-drying, sieving, and chemical extractions, followed by analysis with inductively coupled plasma mass spectrometry and other relevant techniques. The data includes nutrient concentrations correlated with varying degrees of Vachellia karroo canopy cover and identifies boron as a potentially limiting nutrient for tree seedling establishment in non-encroached areas.

The dataset comprises the raw data used in a Kruskal-Wallis rank sum test, highlighting significant differences in soil nutrient concentrations between encroached and non-encroached plots for the Mimosa and Brakfontein sites.

'Bedford grasslands_data_21 Jan 2025_AJM.xlsx' contains nutrient concentration values for each identified site, according to wood cover percentage. The 15 columns contain the following:

1: 'Site name' (The site of the data)

2: 'ID' (The unique sample ID)

3: 'WC %' (the category of wood cover percentage)

4: 'Na' (soil sodium concentration (mg kg^-1))

5: 'Mg' (soil magnesium concentration (mg kg^-1))

6: 'K' (soil potassium concentration (mg kg^-1))

7: 'Ca' (soil calcium concentration (mg kg^-1))

8: 'P' (soil phosphorus concentration (mg kg^-1))

9: 'S' (soil sulphur concentration (mg kg^-1))

10: 'C' (soil carbon concentration (mg kg^-1))

11: 'B' (soil boron concentration (mg kg^-1))

12: 'Mn' (soil manganese concentration (mg kg^-1))

13: 'Cu' (soil copper concentration (mg kg^-1))

14: 'Zn' (soil zinc concentration (mg kg^-1))

15: 'pH' (soil pH concentration (mg kg^-1))