[A-HW22] Material transportation and cycling at the land-sea interface: from headwaters to the ocean

[AHW22-P07] Evaluate nitrogen transport during heavy rainfall event in a rural city catchment using an hourly time-step hydrologic model

*Kunyang Wang¹, Shin-ichi Onodera¹, Mitsuyo Saito¹ (1.Graduate School of Advanced Science and Engineering, Hiroshima University)

Keywords:Kurose River, nitrogen discharge, non-point source pollution, hourly simulation, Soil & Water Assessment Tool

Precipitation is the main driver of nutrient losses. Previous research has suggested that nutrient losses from soils during periods of heavy rainfall may account for the majority of total losses throughout the year. However, current research on soil nutrient loss during heavy rains cannot yet fully understand the differences in the nutrient loss process between different surface and soil properties during heavy rains. This is mainly due to the limitations of the data. However, modeling studies can simulate nutrient losses under different lands and soils under different precipitation conditions through mathematical modeling with limited data.
Kurose River catchment is located in a developing rural city of Hiroshima prefecture, covering approximately 39.5 km², with average annual rainfall of 1467 mm and major occurring during July and August. The objective of this study is to evaluate nitrogen transport during heavy rainfall event in Kurose River catchment and analysis different intensities of precipitation cause nutrient loss pressure on different land and soil types. Provide useful information for addressing climate change, avoiding future environmental pollution and sustainable development.