Taking on the Gulf Dead Zone
Every year approximately 1,500,000 metric tons of nitrogen and phosphorus flow from the Mississippi River basin into the Gulf of Mexico. Largely from fertilizers used on farmland, these nutrients are washed into the Mississippi river and its tributaries to enter into the Gulf of Mexico where they contribute to what is called a “dead zone”. Dead zones are low oxygen areas in the ocean that kill off large amounts of ocean life and damage ecosystems. The Gulf of Mexico dead zone is one of the largest of its kind, harming the environment and industries of the gulf.
The formation of the Gulf of Mexico dead zone is a result of excess farming nutrients entering the Mississippi River basin. Roughly 41 percent of American waters flow into the Gulf of Mexico through the basin, predominantly flowing through the large farming areas of the corn belt. When nutrients like nitrogen and phosphorus enter the gulf they promote dense algae growth and as the algae dies it is decomposed by bacteria that consumes oxygen. This leads to a state of hypoxia, or low oxygen, forcing mobile animals to flee and choking other animals that cannot escape, severely decreasing aquatic life in the dead zone. These effects are exasperated during summer months where seasonal stratification of waters in the gulf prevents mixing of oxygen-rich waters with oxygen-poor waters.
The size of the dead zone in the gulf has steadily increased over the last 10 years, with the largest recorded dead zone reaching 9,776 square miles or roughly the size of Maryland. This growth is accelerated by climate change which has produced extreme weather events such as excessive rainfall and floods throughout the midwest. In May of 2018 the water discharge from the river basin was 67 percent higher than the long term average, carrying almost 200,000 metric tons of nitrate and phosphorus in one month alone. The dead zone has reduced fishing opportunities and forced fishermen to move further from the coast, costing money and time. With the Gulf of Mexico accounting for 40 percent of the nation's seafood it is estimated that the gulf dead zone costs the seafood and tourism industry $82 million a year. To reduce the dead zone size in the gulf it is important that action is taken to prevent nutrient leaching.
Currently actions are being taken on multiple fronts to reduce the leaching of nitrogen and phosphorus into the Mississippi River basin. Programs like the Atchafalaya River Basin Initiative have bought large areas of forest in the basin and worked to restore wetlands that naturally filter the water before it reaches the gulf. Other projects have focused on farm-based strategies to reduce run-off including more efficient and effective use of fertilizers. These actions are helping to stem nutrient run-off from entering the gulf, but it is also important we look to other innovative and sustainable solutions that can help prevent the nutrients from even leaving the farm.
Biochar decreases agricultural run-off into waterways.
One sustainable solution comes in the form of a char-like commodity called biochar. Biochar is the product of a process that converts organic matter, such as corn stover or other farm waste, into a coal-like material through a process called pyrolysis. Due to the biochar's properties, it has a wide array of benefits when added to soil. Critically, biochar has been proven to attract and hold moisture, nutrients, and agrochemicals. Biochar’s nutrient holding properties are especially important because it significantly reduces the run-off of nitrogen and phosphorus. The increased use of biochar can not only help by reducing leaching of harmful nutrients and chemicals but also reduce the need for reapplication of fertilizers, further lowering the potential harm to the health of the environment. Biochar application also provides sustainable co-benefits including carbon sequestration, enhanced crop yields, and more diverse soil microbiology.
The Gulf of Mexico dead zone is a growing environmental and economic disaster and reducing nutrient leaching from farms throughout the Mississippi River basin is critical to shrinking the dead zone. The implementation of biochar use and biochar production for farmers provides a solution that mitigates nutrient leaching while also improving farming outcomes, reducing fertilizer use, and fighting climate change. With biochar we can create economic and environmental impacts for both the farming and fishing industries, forming sustainable practices for a safer and healthier future.
About the Author: Colin Hughes, is a Legal Intern at Amata Green (Summer 2020). Colin Hughes is a graduate from Stony Brook University in N.Y. where he earned his B.A. in Political Science and Psychology. Mr. Hughes is currently pursuing a J.D. at the University of Maryland, Carey School of Law with a focus in Environmental Law. His interests include climate change policy, natural resource management and environmental regulation.
