Intensive farming harms the ocean
Plants in bloom are not always good news. When soil-enriching nutrients used in agriculture seep into the ground, streams and rivers, and eventually into the sea, they overfeed algae and plankton. Algal blooms end up taking up more space, light and oxygen, forcing many other species to flee or die.
You can spot the bright green, red or brown overgrowth of algal blooms from far away. Or worse, smell them. They invade the water’s surface and block sunlight from passing through, in a phenomenon called eutrophication. The blooms also consume most of the oxygen, leaving little chance of survival for nearby species and making it impossible for us to swim and enjoy the sea. When algae eventually die, they pile up on the seabed and decompose, gradually consuming oxygen and creating “dead zones” where nothing can grow and animals can’t live. In the Baltic Sea, there is now a dead zone as big as Ireland.
Algae bloom this way because they have too much to eat. Rainwater trickles through fields, picking-up nitrates and phosphates from agricultural fertilisers along the way, and runs off into streams, rivers, and eventually the ocean. Other types of farming, such as livestock (and their manure) or fish farms (and related fish food and feces), add to the amount of nutrients in the water. Throw in the overflow from badly maintained sewage systems and nutrient-rich wastewater dumped by industry, and you end up with seas full of nutrients… and algae.
We can all make a change by rethinking our habits, but the big change will come from our governments.