Algae Green

Facts about algae:

The marine flora is divided into 3 main categories, the micro-algae (small and usually in the water column), the macro-algae (large and usually attached to rocks on the sea floor) and the true vascular plants which are very similar to terrestrial plants and grasses.
Macro-algae or seaweeds (an un-adapted but common name for such a beneficial organism!) are divided into 3 major divisions, green, red and brown based on their pigmentation. Marine algae is not all “weeds” as they contribute to important carbon/oxygen interactions, nutrient uptake and transformations and constitute shelters, oxygen and food source for numerous marine organisms.
Most of the seaweed species grow along the coastline, therefore, their natural composition depends on the local conditions in terms of availibility of nutrients, light, salinity, depth, freshwater supply (rivers, rain…) and obviously pollution. Marine shoreline life is also regulated by the tide cycles, a phenomenon that is more or less marked from one part of the world, to another.
 
In the brown seaweeds, the term “kelps” generally regroup the algae that never emerges at the low tides whereas species such as Fucus sp. or Ascophyllum nodosum support emersion and immersion periods of several hours during each tide cycle (about 12 hours). Consequently, this natural fact has induced very important adaptation requirements for these species which confer them a particular general composition.