Global Soil Water Stable Isotope Dataset
Description
The soil water stable isotope dataset comprises three components: web-based data, measured data, and reference data. The web-based data are sourced primarily from public isotope platforms and shared databases; the measured data come from long-term observations in representative basins of the arid region in Northwest China; and the reference data are systematically compiled from peer-reviewed literature and supplementary materials from both domestic and international sources. The dataset includes 463 soil water sampling sites across six continents, covering the period 1975–2024. Since 2015, we have established and operated an ecohydrological observation system in representative basins of Northwest China (e.g., the Shiyang River Basin) to continuously collect soil water δ2H and δ18O data, which serve as a key source of measured data for this dataset.
Files
Steps to reproduce
Before the experiment, refrigerated soil-water samples were removed from the freezer and allowed to thaw at room temperature. Once fully thawed, they were transferred to standard 1.5 mL glass sample vials. A 0.45 μm membrane filter was used to remove impurities such as silt and dust. Stable isotopes were measured with a liquid water isotope analyzer (DLT-100, Los Gatos Research, USA). Each sample was measured six times in succession; the first two measurements were discarded to avoid residual effects, and the mean of the last four measurements was taken as the isotopic result. To ensure data accuracy, LIMA was used for quality verification of the raw data; only data that passed the software checks were retained, and analyses failing the checks were repeated. In addition, all isotope data were manually reviewed to ensure complete and clear information on longitude, latitude, sampling time, and isotopes, and outliers and duplicate records were removed.
Institutions
- Northwest Normal UniversityGansu, Lanzhou