Speakers

Biography

Dr. Mounkiala Hamani Abdoul Kader is a postdoctoral researcher at the College of Tropical Crops, Hainan University, Haikou, China. He obtained his Master and PhD degree in 2020 and 2023, respectively at the Graduate School of Chinese Academy of Agricultural Sciences. Throughout his training in Agricultural Water-Soil Engineering and Agronomy, he has been fascinated by the ability to conduct research, which has both scientific and intellectual potential. After completing his graduate studies and gaining significant research experience in the fields of Agronomy and Irrigation Science, he see himself in an academic career as a future research institution member, working with young scientists and engineers to develop innovative solutions with scientific potential and application. His research focuses on agricultural water-fertilizer management and mitigation of greenhouse gas emissions.

Abstract

Soil evaporation has a significant role in regulating the local climate and non-productive water loss. The stable isotope ratios of water (²H/¹H and ¹⁸O/¹⁶O) are excellent tracers for studying water movement and flux. According to the principle of evaporation enriching isotope ratios, three indicators, including the deuterium excess (d-excess), the slope of soil water evaporation line (SEL), and the line conditioned excess (lc-excess), have been established to express the soil evaporation process. However, their differences and the factors affecting these indicators must be better understood under distinct rainfall years' conditions. In this study, d-excess, SEL, and lc-excess were calculated according to the hydrogen and oxygen isotopes of soil water content during the main growth period of winter wheat under distinct rainfall (wet, regular, and dry ) years. The influencing factors of d-excess, SEL, and lc-excess, respectively, soil, vegetation, and meteorology, were analyzed using various methods. The current study revealed a decreased correlation between slope and lc-excess/d-excess during the wet, regular, and dry years. Three analytical methods showed that meteorological factors were the main controlling factors for d-excess, SEL, and lc-excess during the wet year. During the dry and regular years, meteorological, soil, and vegetation and their interactions combined to influence d-excess, SEL, and lc-excess. Compared with the slope of SEL, the lc-excess can better indicate the combined results of soil evaporation because it can be simultaneously affected by soil, vegetation, and meteorological factors. In contrast, the slope of SEL can only be affected by meteorological factors. The results of this study may help calculate soil evaporation by lc-excess.