Evaluation the Severity of Aquatic Environments Desertification
Thisinvestigationhasbeenconductedtofindcriteriasuitable to p l a c e aquatic environmentsin oneofthe desertificationclasses. Thecriteria suggested put t i n g the aquatic ecosystems in five degree of severity. These areslight, moderate, severe, verysevere and exceptionally or catastrophic. These depend on the main reasons which cause aquatic ecosystems deterioration as follow: 1. Slight desertification has high plankton population , underexploited , no pollution, excellent*D.O levels , salinity values less than 0.5 ppt , PH = 7.00 and productivity reduceless than10 % 2. Moderate hasmoderate plankton population, moderately exploited , slight pollution, very high D.O levels ,, salinity values 0.5 -17 ppt and pH =8.069 and productivity reduce 25% 3. Severe, low plankton population, fully exploited, low pollution, high D.O levels , salinity values 16 ppt , slight decrease in pH from 8.069 and productivity reduce 50 % 4. Very severe, slight plankton population. Overexploited. moderate pollution Moderate D.O levels, salinity values 32 – 37 ppt, pH more decrease in pH 8.069 productivity reduce 75 % 5. Exceptionally or catastrophic, noplankton population , depleted , High pollution low D.O levels , salinity values more than 37 ppt ,high decrease in pH PH 8.069 andzero productivity. These criteria could be usedtoplace any aquatice c o s y s t em inoneofthe desertificationclasses.