Adapting to stress
Physical environment has a tremendous affect on seaweeds, but the seaweed is an amazingly resilient algae.
The seaweed absorbs gases and nutrients from the water and rely on the continuous movement of the water running through the plant to avoid nutrient depletion. Sometimes, when ocean waves and currents are strong, seaweeds are ripped right off the rocks so to cope with the stress of the waves, the strong holdfasts, flexible stipes and blades of the plant allow it to bend as waves mover over the plant.
Exposure to air and weather conditions also create stress on seaweeds. Seaweed lose water through evaporation when exposed to air, and some can dry out almost completely when tides are low, however they take up water again with rising tides and are able to fully recover.
Seaweed in tidepools are exposed to changes in water temperature and fluctuating salinity levels caused by weather conditions. When water in tidepools warm up and evaporate, the salinity in the water is higher and when it rains, salinity decreseas.
Surviving in the intertidal zone, seaweeds must be able to tolerate the many stresses the plants are exposed to.
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