Soil Properties and Vegetation Survey Data in the Kalamaili Nature Reserve, China

Field sampling was conducted from August 15 to 20, 2019, within the Kalamaili Nature Reserve in China. A total of 13 sampling sites were established, with five 10 m × 10 m quadrats randomly placed at each site.
Soil sampling: Intact rhizosphere soil cores were collected from 65 plots using PVC corers, sealed, and stored at 4°C for analysis. Samples were scanned with a microfocus CT system at 100 kV/100 μA, and 3D volumes were reconstructed with isotropic 30-μm voxels. Reconstructed images were downsampled to 60-μm voxels, and a cubic region of interest was cropped from the center for analysis to avoid edge effects. Soil water content was determined by the gravimetric method, and total salinity was calculated from the mass difference of soil extracts before and after organic matter removal. Total nitrogen was measured using the Kjeldahl method, total phosphorus was determined spectrophotometrically via the molybdenum blue method, and pH was measured with a calibrated glass electrode.