Bay in the Balance: Ocean Acidification Threatens the Chesapeake Ecosystem

As a Marylander, one of my favorite things to do is make the trek up to the Chesapeake Bay. Its sparkling waters, abundant wildlife, and dazzling beauty set it apart as a prime jewel of the East Coast. Nothing can compare to the experience of paddling down the Potomac River on a sunny day, the boughs of a sycamore arching overhead. Poetic license is unnecessary to describe the Bay and its many wonders.

Apart from being a stunner, the Bay provides major cultural and economic benefits. Its unique way of life is perfectly encapsulated in the small towns of Smith Island (population 364), where watermen make a living from the estuarys bounty. On a recent visit, one local said to me, We truly build our lives around the water. From the local fisherman to larger commercial operations, the Chesapeake provides $3.39 billion annually in seafood sales alone, part of a total economic value topping 1 trillion.

The stability of these waters is endangered by the exponentially increasing problem of ocean acidification. This occurs when carbon dioxide in the atmosphere is absorbed into bodies of water, causing surging acidity levels. Acidification leads to the protective carbonate coverings of shellfish to disintegrate, causing dieoffs in oysters, mussels, and other bivalves. Oyster reefs serve to filter the Bay without a thriving population, harmful pollutants run rampant. High acidity causes oysters growth to be stunted, so that shellfish fisheries cannot profit from the smaller, thinner shells. According to the Chesapeake Bay Foundation, Maryland and Virginia have suffered losses exceeding $4 billion over the last three decades stemming from the decline of oyster health and distribution.

The losses arent economic alone. Characterized by rich biological diversity, an estimated 2,700 species call the Bay their home. This remarkable level of biodiversity is threatened by ocean acidification. The loss of even one species causes a ripple effect through the entire food web, sending it into a state of unbalance. According to a 2004 study in Science, the survival of threatened and non-threatened species is closely linked: when an endangered species goes extinct, dependent ones suffer. A particularly disturbing image of acidification is its effect on fish neurology. Their decision-making skills are significantly delayed to the level where they sometimes swim directly into the jaws of predators.

Zoom out from the Chesapeake to the world ocean. Skyrocketing acidity is present in almost every aquatic biome on our planet. It is clear that we need a solution to our acidifying world. However, methods that at first appeared brilliant have either been limited by their feasibility or come to be outweighed by their negative side effects, ultimately prolonging the search for a solution.

The surprising method of dumping massive amounts of iron sulphate into the water is based on the principle that iron fertilizes phytoplankton, microscopic organisms found in every body of water. The energy phytoplankton gain from the iron allows them to bloom, absorbing CO2 from the atmosphere and the ocean or in this case, the Bay. When the phytoplankton die they sink to the bottom of the ocean, locking the CO2 there for centuries. In 1988, the late oceanographer John Martin proclaimed, Give me a half tanker of iron, and I will give you an ice age. It is theorized that fertilizing 2% of the Southern Ocean could set back global warming by 10 years.

Why not implement this magic fix? First off, iron fertilization is very controversial, and has come under fire for its negative side effects. A 2016 study in Nature determined that the planktonic blooms would deplete the waters of necessary nutrients. Additionally, when the large bloom dies, it would create large dead zones, areas devoid of oxygen and life. Side effects aside, this technique may be altogether ineffective. CO2 may simply move up the food chain when the phytoplankton are eaten and be respired back into the water. This was observed when the 2009 Lohafex expedition unloaded six tons of iron off the Southern Atlantic. The desired phytoplankton bloom it caused was promptly gobbled up by miniscule organisms known as copepods.

The alternative solution of planting kelp seems less drastic and more promising. Revitalizing the expansive forests of algae is believed to be effective in sucking up underwater CO2. Kelp grows as quickly as 18 inches a day, and once established offers the added benefits of providing a habitat for marine species and removing nutrient pollution. Researchers from the Puget Sound Restoration Fund, who have been monitoring the capability of this process, found that kelp forests are effective at diminishing acidification on a local scale. While planting key carbonsucking species across the ocean would not be a feasible solution, kelp forests could help solve the Bays acidification crisis.

A third option: instead of cleaning up after this anthropogenic problem, stop it at its root. Environmental regulations enacted by the US government are an effective way to achieve conservation goals. The EPA collaborates with the Subcommittee on Ocean Science and Technology to investigate the impacts of acidification on ocean chemistry and biology, as well as monitor estuaries such as the Chesapeake. However, given that the EPA is poised to roll back their conservation obligations and instead direct them to individual states, there is a rising need for state and local governments to take action in preserving the Bays health. An example of how to counter the acidification of the Bay would be to bring up to date existing zoning policies, such as those in Virginias 1998 Bay Preservation Act, to stay on par with the rapidly increasing impacts of CO2.

In the end, there is no straightforward fix a combination of methods is paramount. Efforts by environmental agencies, all levels of government, private industry, and academics must be intertwined in solving this problem. This will only occur with informed interest from citizens whose love for their Bay is as bountiful as its waters.

Author: Clara Benadon (United States).