Predictive modeling of hawiza marsh eutrophication

Abstract EN

The term "eutrophic" refers to system rich in nutrients, and hence Eutrophication means nutrient enrichment, particularly by increasing levels of nitrogen and phosphorus [1].

In lakes, phosphorus is generally regarded as the limiting nutrient for primary production [2] implying that increasing phosphorus concentrations will result in increasing production of phytoplankton and benthic algae.

Excessive amounts of phytoplankton cause low Secchi depths and may consequently wipe out the benthic flora by shading the light [3].

Toxic cyanobacteria tend to bloom when nutrient levels are high [4].

Apart from being a nuisance in their own right, settling phytoplankton may cause anoxia in hypolimnetic waters as their decomposition consumers oxygen [5], and this may result in extinction of the benthic fauna [6] and fish feeding on such animals.

Altogether, these Eutrophication effects threaten the foundations of aquatic ecosystems.

The low oxygen levels in hypolimnetic waters associated with Eutrophication may also cause mobilization of phosphorus in the sediments, thus inducing a feedback mechanism where already high nutrient levels increase even more.