Earth Day – 22 April 2016

On Earth day, remember that 70% of our planet is Oceans

Copyright M. Dohmen

 

Athough the theme of Earth Day 2016 is trees, take a minute to think about marine plants. There are some marine trees, which are known as mangroves, that play a very important role in tropical, coastal zones. Mangrove forests are hotspots of biodiversity and also provide valuable ecosystem services. For example, they protect the coast from erosion and natural hazards such as storm surges and even tsunamis! The complex network of roots of mangroves provide a safe haven and act as a nursery for the baby fish. Unfortunately mangroves are often cleared to make space for aquaculture ponds and agriculture.

 

 

Copyright: NOAA

Copyright: NOAA

Other plants in the ocean are also threatened, they include seagrass (or eelgrass) meadows and kelp forests. Seagrass meadows are also terrestrial “flowering” plants that live in the sea, in soft sediments such as sands. Seagrass meadows can occur along Artic to Tropical coasts and are widespread in all European seas. Seagrasses also provide valuable ecosystem services such as nurseries for juveniles, and stablizing sediments, but they are very vulnerable and easily destroyed by turbid water, dredging, anchoring and trawling. This is the case of the endemic Posidonia oceanica in the Mediterranean.

 

 

Copyright: S. Cunningham

Copyright: S. Cunningham

 

Kelp forests of large algae occur in temperate zones such as the rocky coasts of the North East Altlantic, from Norway to Portugal. They are very productive, dynamic ecosystems that can be easily disrupted. For example, the over-harvesting of lobsters may result in the proliferation of their prey, such as sea urchins, who then over-graze the kelp and destroy the forests.

 

 

 

Our Oceans are also full of microscopic phytoplankton, which are protozoa and blue-green bacteria rather than plants such as kelp, seagrasses and mangroves. All these organisms are very important since they produce oxygen, they are the lungs of the ocean! They also play an important role by fixing carbon dioxide simultaneously.

DEVOTES project is committed in studying and assessing the biodiversity of seas, including all the above mentioned components, assisting managers in achieving sustainable and health seas.

More information about the Earth Day can be found at www.earthday.org.