Tiansong Qi (2025)
Project Title: Incorporating wetland characteristics in watershed-scale hydrologic modeling in depression-dominated areas
Project ID:
Fellow: Tiansong Qi
Adviser(s): Xuefeng Chu and Marinus Otte
1. Project Impact: Provide a synopsis of the primary findings and impact of the project (approximately 250 words).
Depressional wetlands are important components of watersheds and play a significant role in watershed hydrologic cycles by affecting surface runoff generation, overland flow routing, and other processes. The threshold-controlled, filling-spilling processes over individual wetlands result in dynamic ponding storage and varying partial contributing areas of surface runoff to a watershed outlet. However, such complex hydrologic processes are usually oversimplified in conventional watershed models by assuming a lumped, constant contributing area. This project aimed to improve watershed-scale hydrologic modeling, especially for depression-dominated regions, by quantifying the influence of individual depressional wetlands. In this project, a four-factor hydrologic response unit (HRU) redefinition technique was proposed to characterize the variations of topographic features, soil properties, and land covers in depressional areas and a novel HRU-level wetland modeling approach was developed to account for the influence of dynamic ponding storages of individual depressional wetlands on surface runoff generation and overland flow routing. The new modeling approach was applied to the Upper Forest River watershed in North Dakota, demonstrating its improved modeling performance and enhanced capability in simulating the spatially and temporally varying characteristics of ponded water across individual depressional wetlands, as well as the stepwise expansion and contraction of dynamic partial contributing areas. This project provides a novel modeling framework for evaluating and elucidating the influences of depressional wetlands on watershed hydrologic processes, which can further help address the relevant water resources management issues.
2. Publications: Please provide a list of all reports, journal articles, book chapters, theses, dissertations, etc. published during the reporting period as a result of projects supported with annual base (104b) federal and/or ND SWC funds. Please provide URLs for publications where available.
Peer-reviewed Journal Papers
Qi, T., and Chu, X. 2025. A depression-oriented four-factor redefinition of hydrological response units. Hydrological Sciences Journal, 70(14), 2575-2589, https://doi.org/10.1080/02626667.2025.2549778.
Khanaum, M. M., Qi, T., and Chu, X. 2025. Dynamic Partial Contributing Area (DPCA) approach: Improved hydrologic modeling for depression-dominated watersheds. Journal of Hydrology, 658, 133077, https://doi.org/10.1016/j.jhydrol.2025.133077.
Theses and Dissertations
Qi, T. 2025. Improved Watershed-Scale Hydrologic Modeling for Characterizing Dynamic Contributing Areas and Threshold-Controlled Overland Flow from Depressional Wetlands. Doctoral dissertation. Civil Engineering, College of Graduate and Interdisciplinary Studies, North Dakota State University, Fargo, ND (available at: https://www.proquest.com/docview/3280829427?pq-origsite=gscholar&fromopenview=true&sourcetype=Dissertations%20&%20Theses).
3. Presentations: Please provide a list of all conference presentations and seminars during the reporting period as a result of projects supported with annual base (104b) federal and/or ND SWC funds.
Qi, T. 2025. Improved Watershed-scale Hydrologic Modeling for Characterizing Dynamic Contributing Areas and Threshold-controlled Overland Flow from Depressional Wetlands. Water Seminar Series, North Dakota Water Resources Research Institute, November 3, 2025, Online.
Qi, T., and X. Chu. 2025. Redefinition of Hydrologic Response Units for Capturing Dynamic Partial Contributing Areas in Depression-dominated Watersheds. ND EPSCoR 2025 State Conference, October 21, 2025, Fargo, ND.
Qi, T., and X. Chu. 2025. Incorporating the Impacts of Individual Surface Depressions in Watershed-scale Hydrologic Model. South Dakota Student Water Conference, October 14, 2025, Brookings, SD.
Qi, T., and X. Chu. 2024. An Enhanced Modeling Framework for Simulating Hydrologic Processes in a Depression-dominated Watershed. ND EPSCoR 2024 State Conference, November 21, 2024, Grand Forks, ND.
Qi, T., and X. Chu. 2024. A Four-factor Redefinition Technique of Hydrologic Response Units for Depression-dominated Watersheds. South Dakota Student Water Conference, October 15, 2024, Brookings, SD.
