Study on the relationships among the water, temperature, salinity, and nutrients of aeolian sandy soils in the west arid zone of China

The interaction among soil water, temperature, salinity and nutrients is crucial for improving soil utilization efficiency, especially in the aeolian sandy soil of the arid areas in western China. To explore the interrelationships among these variables, a maize planting experiment was conducted at a test field in Baijitan National Nature Reserve of China in 2024. Drip irrigation was adopted, and a total of four drip irrigations were carried out during the planting period, with irrigation volume of 40 m3/time during the seedling stage, and 50 m3/time were used during other stages. Moreover, a small-scale agricultural meteorological station was set up at the test field to obtain data on soil water, temperature, salinity and nutrients of the 0–20 cm, 20–40 cm, 40–60 cm, 60–80 cm, 80–100 cm soil layers. The statistical analysis methods such as Pearson correlation coefficient method and least squares method were used to analyze these data, which monitored the changes of various soil indicators during the growth period of maize more effectively than the traditional methods. The results showed that the vertical distribution of soil water followed the parabolic model, and the correlation between surface water and salinity was significantly enhanced after irrigation. Soil temperature is negatively correlated with water and conforms to a cubic curve relationship. Most importantly, this study reveals the asymmetric regulatory mechanism of nutrients on hydrothermal factors: although the content of NO3− significantly increases soil water, it has a negative effect on temperature, while Nitrogen (N) content shows a positive effect on temperature.