The associated data for the article "Changes of photosynthetic characteristics, soil nutrients and antioxidant enzymes of Caragana korshinskii in different forest ages in Mu Us Sandy Land"

Data were collected from Caragana korshinskii shrubland at five forest ages (7, 20, 30, 50, 70 a) in the Baijitan National Nature Reserve, Lingwu, Ningxia, with four replicate plots per age.The dataset includes the following measurements:Photosynthetic characteristics: net photosynthetic rate (Pn, μmol·m⁻²·s⁻¹), transpiration rate (Tr, mol·m⁻²·s⁻¹), intercellular CO₂ concentration (Ci, μmol·mol⁻¹), and stomatal conductance (Gs, mol·m⁻²·s⁻¹), measured using a Li-6800XT portable photosynthesis system;Soil nutrients: soil organic carbon (SOC, g·kg⁻¹), total nitrogen (TN, g·kg⁻¹), and total phosphorus (TP, g·kg⁻¹) in the 0–20 cm soil layer, determined by the K₂Cr₂O₇ oxidation method, Kjeldahl method, and molybdenum-antimony colorimetric method, respectively;Antioxidant enzyme activities: leaf peroxidase (POD, U·g⁻¹·min⁻¹) and superoxide dismutase (SOD, U·g⁻¹·min⁻¹), determined by the guaiacol method and nitroblue tetrazolium method, respectively.The data file is provided in Excel format, containing both raw observational data and processed mean values for each forest age, which can be used to reproduce Figures 1–5 and Table 2 in the paper.