水文学: 現在の研究

Restoration versus Re-flooding: Mesopotamia Marshlands

Abstract

Ali Abdul Zahra Douabul, Nadia A. Al-Mudhafer Abdulzahra A. Alhello1, Hamid Talib Al-Saad and Sama Sameer Al-Maarofi

The current water physiological and chemical parameters in the re-flooded marshes of the Mesopotamia are investigated from March 2005 to August 2008. Generally, desiccation, among the several natural and anthropogenic activities (water shortage, dams’ constructions), had the worst damage sequences that led to destroy the Mesopotamian’s ecosystem. Understanding the current physicochemical structure of the re-flooded marshes are important in order to evaluate the ecological function of the newly wetlands. This study will assess the ecological function of some of the re-flooded marshes based on their historical status in the 1970’s. The assessment will observe the overtime changes of water quality parameters, nutrients and major ions concentrations of the Mesopotamian marshlands before and after desiccation in thirty re-flooded marshes. During the study period, and under the stagy hydrological situation of Iraq, the average salinity concentration of the marshes was increased from 0.5 ppm to 1.6 ppm. The pH values were mostly in the basic range which is similar to previous studies. High range of dissolved oxygen concentrations were recorded that mostly related to the seasonal differences and photosynthesis. The significant differences between the major ions concentrations among the three marshlands indicate the differences in the water resources of each marshland, which mainly related to the tidal effect of Arabian Gulf via Shatt Al-Arab River. The early monitoring of PO₄, NO₂, NO₃, and SiO₂ concentrations were high and then their concentrations started to decline overtime, which is good indicator that the marshlands are naturally are recycle and remove the extra concentrations of nutrients and avoid nitrification. Also the principal component analysis indicates that the historical conditions of the marshlands were changed dramatically overtime even before the desiccation period.