الفهرس 
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Abstract
Four green microalgae species, namely Chlorella minutissima, Scenedesmus dimorphus, Monoraphidium griffithii and Monoraphidium pusillum were selected as test algae. According to the results of intensive outdoor and lab growth assessment experiments, only the two species Chlorella minutissima and Scenedesmus dimorphus were selected for further outdoor growth experiments. These two microalgae were grown in small experimental glass raceway open ponds. The outdoor growth experiments continued for one full year (12 months). Nutrient renewal and biomass harvest were achieved bi-daily, weekly or bi-weekly according to the research objectives and the parameters to be investigated. A host of different physical, chemical and biochemical parameters with specific relevance to the scope of this study were regularly monitored. These parameters, with their mean annual values given between brackets, include light intensity (102 wm-2), temperature (25 0C), pH (9.87), water evaporation (0.87 L day-1), algal dry weight (1.2 g/l), hexane extract of crude oil (6.5% w/w), protein content (38.2 % w/w), and carbohydrates (13.7% w/w). No significant (p ≤ 0.05) differences were noticed in dry weight biomass and the cellular contents of lipids, proteins and carbohydrates of Chlorella minutissima and Scenedesmus dimorphus. The GC/MS analysis indicated the suitability of algae lipids as biodiesel feedstock. High protein and carbohydrate contents of both test algae may suggest the significance of their biomass for animal feed. However, the most peculiar experimental outcome was the noticeable high outdoor biomass production rate as the mean annual value was typically above 1.0 g dry.wt per liter culture per day. This realistic rate of biomass production indicates the potential promise of both Chlorella minutissima and Scenedesmus dimorphus for economic purposes. The data obtained were statistically analyzed to reveal the relationships between certain outdoor growth controlling factors, algal biomass, and the cellular contents of potential economic concern.