Eutrophication process - WWF Poland

Summary

Eutrophication is a major environmental challenge for the Baltic Sea, caused by excessive nutrients like nitrogen and phosphorus from fertilizers and livestock manure. These substances flow into the sea, fueling algae and cyanobacteria blooms. The blooms reduce water clarity, preventing sunlight from reaching deeper waters, affecting photosynthesis. As the blooms decay, oxygen is consumed, creating 'dead zones' where life cannot survive. The depletion of oxygen also leads to the release of harmful hydrogen sulfide. The health of the Baltic Sea is impacted by human activities, and everyone is responsible for its protection.

Takeaways

• 😀 Eutrophication is the primary environmental challenge for the Baltic Sea.
• 🌍 The Baltic Sea is surrounded by land on almost all sides and is home to over 80 million people.
• 🌾 Intensive agriculture in the Baltic Sea region has been a key factor in increasing nutrient pollution.
• 💧 Fertilizers, both chemical and natural, contain nitrogen and phosphorus, which contribute to eutrophication.
• 🌧️ Surplus fertilizers and unprotected livestock manure are washed into groundwater and rivers, eventually reaching the sea.
• ⚡ Nitrates and phosphates carried by rivers cause an excess of nutrients in the Baltic Sea, leading to harmful algae and cyanobacteria blooms.
• 🦠 Algae and cyanobacteria blooms reduce water clarity, making it harder for sunlight to reach deeper water layers needed for photosynthesis.
• 💀 As blooms die, their decomposition by bacteria consumes oxygen, creating oxygen-deprived zones at the bottom of the sea.
• 🚫 Lack of oxygen in these dead zones disrupts life, with anaerobic bacteria releasing harmful hydrogen sulfide.
• 🌊 Dead zones are oxygen-free areas where most marine life cannot survive.
• 🌱 We all have a role to play in protecting the Baltic Sea and reducing the impacts of eutrophication.

Q & A

What is eutrophication, and why is it a challenge for the Baltic Sea environment?

Eutrophication is the process where excess nutrients, primarily nitrogen and phosphorus, lead to overgrowth of algae and cyanobacteria in the water. This is a significant environmental challenge for the Baltic Sea because it disrupts aquatic life and reduces water quality.

How is the Baltic Sea geographically positioned, and what makes its environment vulnerable?

The Baltic Sea is surrounded by land on almost all sides and is inhabited by over 80 million people. This makes the sea particularly vulnerable to human activities, such as intensive agriculture and industrialization, which lead to nutrient pollution.

What role do fertilizers play in the eutrophication process in the Baltic Sea?

Fertilizers, both chemical and natural, are used in agriculture to improve crop yields. These fertilizers contain compounds of nitrogen and phosphorus, and when surplus fertilizers are not absorbed, they run off with rainwater into groundwater and rivers, eventually reaching the sea.

What types of nutrients are carried by rivers into the Baltic Sea, and how do they contribute to eutrophication?

Rivers carry nutrients such as nitrates and phosphates into the Baltic Sea. These nutrients cause an overgrowth of algae and cyanobacteria, leading to reduced water clarity and triggering further environmental imbalances.

How do algae and cyanobacteria blooms impact the Baltic Sea's water quality?

Algae and cyanobacteria blooms create water turbidity, blocking sunlight from reaching deeper layers of water. This limits photosynthesis, negatively affecting aquatic life and further destabilizing the ecosystem.

What happens to algae and cyanobacteria when they die, and how does this affect the sea?

When algae and cyanobacteria die, they sink to the sea's bottom, where they decompose. This process consumes oxygen, leading to oxygen depletion in the water, creating dead zones where most life cannot survive.

What are 'dead zones,' and how are they formed in the Baltic Sea?

Dead zones are areas in the sea with low or no oxygen, where life cannot survive. They are formed when decomposing organic matter, such as dead algae and cyanobacteria, consumes large amounts of oxygen in the water.

How do anaerobic bacteria contribute to the formation of dead zones?

When oxygen levels drop in the sea, anaerobic bacteria take over the decomposition process. These bacteria release hydrogen sulfide, which is harmful to other organisms and contributes to the creation of dead zones.

Why are dead zones detrimental to marine life?

Dead zones lack oxygen, which is necessary for most marine life to survive. As a result, these areas become inhospitable, leading to a loss of biodiversity and a collapse of the affected ecosystem.

What can we do to help protect the Baltic Sea from eutrophication?

We can reduce the use of fertilizers and improve agricultural practices to prevent nutrient runoff into rivers and the sea. Additionally, protecting natural habitats and supporting policies aimed at reducing pollution are crucial for the health of the Baltic Sea.