Keywords : Ecosystem requirements
Modelling the Ecosystem Behavior of Abu-Ziriq Marsh in South of Iraq Under Different Water Discharges Scenarios
Engineering and Technology Journal,
2019, Volume 37, Issue 10A, Pages 442-452
The marshlands are of fundamental importance to Iraq, a unique ecosystem providing local inhabitants with an essential source of habitat and livelihoods. This paper aims to study the ecosystem behavior of Abu-Ziriq Marsh in the south of Iraq under different scenarios using the Ecosystem Functions Model Program (HEC-EFM) and Hydrologic Engineering Center Data Storage System Visual Utility Engine (HEC-DSSVue). To this end, data was converted from tri-monthly and semi-monthly to daily data using the HEC-DSSVue program. The daily data natural(flow, stage) was used for five years between 2013 and 2018. The prediction process was evaluated using three criteria: correlation coefficient (R), root mean square error (RMSE), and the Nash–Sutcliffe effectivity coefficient (NSE). Results of R, RMSE and NSE for the daily inflow discharge (stage) of natural were 0.98 (0.93), 1.55 (0.19) and 0.95 (0.73). Five scenarios of a percentage decrease in gage(flow, stage) with 2%, 4%, 6%, 8% and 10% were investigated. Results showed that the decrease in discharge from 2% to 8% did not significantly affect environmental relations and could be used by the competent authorities. However, when the discharge was reduced to 10%, the environmental relations were greatly affected and threatened the life of the organisms. In addition to that, results for wetland health reverse lookup at the fifth scenario show that Abu–Ziriq Marsh need (70.2%) as a percent of the time, when flows equal or exceed four m3/sec. This discharge was chosen because it can be supplied on most days of the year, which is the time needed to be revived when flows equal or exceed 4 (m3/sec).