379987 - Improving the accuracy of Chl-a simulation at high water temperature ranges in the HSPF model
Tuesday, June 5
10:30 AM - 12:00 PM
Location: Greenway IJ
Jin Hwi Kim, Seoul, Korea – Dongguk University; Joo-Hyon Kang, Seoul, Korea – Dongguk University
1. Introduction and purpose
A watershed model such as the Hydrological Simulation Program – Fortran (HSPF) has been widely used to predict water quality and quantity for supporting watershed management actions. However, use of a washed model can be limited due to difficulty in calibration and/or intrinsic limitation of the model. In this study, the HSPF model was automatically calibrated for the flow rate and major water quality parameters including Chl-a. The original HSPF was modified to more accurately simulate Chl-a at higher temperature ranges, which could be more critical conditions for the algal bloom.
The study area was the Sumgang watershed of South Han-river in Korea. The HSPF model was linked to the MATLAB, in which an optimization algorithm was implemented to calibrate the model parameters for flow, water temperature, sediment, nutrients and Chl-a. A series of sensitivity analysis were conducted to select parameters for calibration. To improve the accuracy of Chl-a simulation, the HSPF model was modified and tested.
The HSPF model well simulated the flow, water temperature, and nitrogen but the simulation results of the sediment, phosphorus and Chl-a were less satisfactory. Particularly, the current HSPF model was limited in simulating rapid increase in the Chl-a concentration with the increased water temperature. The HSPF model was modified to simulate the nonlinearity between temperature and the maximum phytoplankton growth rate and the results showed better Chl-a simulation results.
This research was supported by a grant (2015R1D1A1A01056753) from the National Research Foundation of Korea.