biofuels & ocean dead zones
Friday, September 18th, 2009
Biofuels and the growing areas of ‘dead’ ocean may seem worlds apart.
But a new study warns that boosting biofuel crop production in the US could thwart attempts to reduce the expanse of the northern Gulf of Mexico (GOM) that becomes oxygen-depleted every year.
In 2008, a dead zone the size of Massachusetts (over 27,000 square km) formed in the Gulf of Mexico threatening marine wildlife, fisheries and tourism.
The Mississippi River carrying fertilizers into the Gulf of Mexico
why?
Because much of the fertilizers added to cropland – including biofuels – end up washing into rivers and eventually the ocean, causing a phenomenon known as eutrophication that triggers algal blooms. The algae die and sink to the seabed where they are broken down by bacteria. This uses up available oxygen, something that many marine species rely on. An earlier study in 2008 uncovered just how fast these dead zones are spreading.
what’s new?
A computer model of the southern US under various future scenarios suggests that no-matter what crops are grown – even grasses which require fewer artificial fertilizers – if federal plans to produce 36 billion gallons of biofuel by 2022 come to fruition, there may be little hope of curbing the area of the GOM that becomes seasonally inhospitable to wildlife.
This not only has implications for the US and its surrounding seas but also other countries that are considering boosting biofuel production as a way of trying to combat climate change.
biofuel or no biofuel?
This study undoubtedly adds another strand to the debate over whether biofuels can provide a sustainable solution to carbon dioxide emissions, demonstrating how important it is to consider all the potential ecological consequences of biofuels.
But the authors of this study point out that there are ways that biofuel crop production can be rendered less harmful to the aquatic environment:
- plant vegetation along river courses to promote nutrient uptake
- create wetlands
- promote the precise application of fertilizers.
In detail:
The study, Impact of Biofuel Crop Production on the Formation of Hypoxia in the Gulf of Mexico by Costello et al is published in the journal of Environmental Science and Technology.
Biofuels and the growing areas of ‘dead’ ocean may seem worlds apart.
But a new study warns that boosting biofuel crop production in the US could thwart attempts to reduce the expanse of the northern Gulf of Mexico (GOM) that becomes oxygen-depleted every year.
In 2008, a dead zone the size of Massachusetts (over 27,000 square km) formed in the Gulf of Mexico threatening marine wildlife, fisheries and tourism.
The Mississippi River carrying fertilizers into the Gulf of Mexico
why?
Because much of the fertilizers added to cropland – including biofuels – end up washing into rivers and eventually the ocean, causing a phenomenon known as eutrophication that triggers algal blooms. The algae die and sink to the seabed where they are broken down by bacteria. This uses up available oxygen, something that many marine species rely on. An earlier study in 2008 uncovered just how fast these dead zones are spreading.
what’s new?
A computer model of the southern US under various future scenarios suggests that no-matter what crops are grown – even grasses which require fewer artificial fertilizers – if federal plans to produce 36 billion gallons of biofuel by 2022 come to fruition, there may be little hope of curbing the area of the GOM that becomes seasonally inhospitable to wildlife.
This not only has implications for the US and its surrounding seas but also other countries that are considering boosting biofuel production as a way of trying to combat climate change.
biofuel or no biofuel?
This study undoubtedly adds another strand to the debate over whether biofuels can provide a sustainable solution to carbon dioxide emissions, demonstrating how important it is to consider all the potential ecological consequences of biofuels.
But the authors of this study point out that there are ways that biofuel crop production can be rendered less harmful to the aquatic environment:
- plant vegetation along river courses to promote nutrient uptake
- create wetlands
- promote the precise application of fertilizers.
In detail:
The study, Impact of Biofuel Crop Production on the Formation of Hypoxia in the Gulf of Mexico by Costello et al is published in the journal of Environmental Science and Technology.