Florida Bay’s Ecological Problems

A Pouring water into the sea seems harmless enough. But in Florida Bay, a shallow inner-shelf lagoon at the southern end of the Florida watershed that lies between the Everglades and the Florida Keys, it is proving highly controversial, because researchers are still not sure about whether the action will help or hinder the plants and animals that live in the bay.

B What is at risk is the future of the bay’s extensive beds of sea grasses. These plants grow on the bay’s muddy floor and act as nurseries for the economically valuable pink shrimps, Caribbean spiny lobsters and fish. Also in danger is an impressive range of coral reefs that run the length of the Florida Keys and form the third-largest barrier reef in the world. Since the 1980s, coral cover has dropped by 40%, and a third of the coral species have gone. This has had a damaging effect on the animals that depend on the reefs, such as crabs, turtles and nearly 600 species of fish.

C The top priority now is to figure out the cause of this issue. This is because the American government is planning to devote $8 billion over the next 30 years to revitalising the Everglades. Seasonal freshwater flowing into the Everglades, the unique ecosystem home to 68 endangered or threatened plant and animal species, are to be restored in order to improve the region’s ecological health. But they will then stream into the bay.

D Joseph Zieman, a marine ecologist at the University of Virginia, thinks this is a good idea. He advocates that the inadequacy of freshwater in the bay is the primary cause. Actually, Florida Bay has long obtained freshwater mainly from the Everglades. So the blame, he says, lies with the drainage system in the Everglades aimed at turning the marshes into farmland and areas for development. This has caused freshwater flow into Florida Bay to dwindle, making the water in the bay, overall, more saline. Such water of high salinity, he argues, kills the sea grasses and as these grasses rot, nutrients are released to support the planktonic plants and animals, which is also the reason why the bay’s once crystal-clear waters often resemble pea soup now. And in a vicious circle, these turbid blooms block out the sunlight, causing more sea grasses to die and yet higher turbidity.

E Brian Lapointe, a marine scientist at the Harbour Branch Oceanographic Institution at Fort Pierce in Florida, disagrees. He thinks sea grasses can tolerate a much higher level of salinity than the bay actually displays. Furthermore, he notes that in an experiment carried out in the 1990s, freshwater running off from well-fertilised farmland caused not only a fivefold rise in the nitrogen level in the bay but also the blooms of plankton. This was like pouring fuel on a fire. The consequence was mass mortality of sea grasses because of increased turbidity from the plankton. Dr. Lapointe adds that, because corals thrive only in waters where the nutrient levels are low, restoring freshwater rich in nitrogen will do more damage to the reefs.

F It is a plausible theory. The water flowing off crops that are grown on the heavily fer-tilised farmland on the north-eastern edge of the Everglades is rich in nitrogen, half of which ends up in the bay. But Bill Kruczynski, from America’s Environmental Protection Agency, is convinced that nitrogen from farmland is not the chief problem. Some coral reefs well away from any nitrogen pollution are dying, and curiously a few are thriving. Dr. Kruczynski thinks that the escalated nutrients arriving from local sewage discharges from the thousands of cesspits along Florida Bay are part of the problem. He recommends the introduction of a new wastewater management system, such as centralised treatment facilities for wastewater, which is essential to maintain water quality in Florida Bay.

G Such claims and counterclaims make the impact of the restoration plan difficult to predict. If enhanced salinity is the main factor, the bay’s condition will benefit from the Everglades restoration project. If, however, nitrogen is the key, expanding the flow of freshwater could make matters much worse.

H If this second hypothesis proves correct, the cure is to remove nitrogen from farmland or sewage discharges, or perhaps both. Neither will be easy. Artificial wetlands are being constructed to constrain the contaminants being emitted into the bay, thereby purifying the water and improving the wildlife habitat. That would be costly. So too would be the replacement of cesspits with proper sewerage – one estimate puts the cost at $650 million. Either way, it is clear that when, on December 1st, 3,000 square miles of sea around the reefs are designated as ‘protective zone’ by the deputy secretary of commerce, Sam Bodman, it will do nothing to protect the reefs from pollution.

I Some argue, though, that there is a more fundamental flaw in the plan for the bay: the very idea of returning it to a utopian ideal before man wrought his damage. Nobody knows what Florida Bay was like before the 1950s when engineers cut the largest canal in the Everglades and took most of the water away. Dr. Kruczynski suspects it was more like an estuary. The bay that many people wish to recreate could have been nothing more than a changing phase in the bay’s history.

J These debates do not merely involve ecological sustainability but economic growth as well. The economy of the Florida Keys depends chiefly on tourism – the local tourist industry has an annual turnover of about $2.5 billion. People come for fishing-boat trips, for manatee watching or for scuba diving and snorkelling to view the exotically coloured corals. If the plan to restore the Everglades makes problems in the bay and the reefs worse, it could be a very expensive mistake.

uestions 14 – 17

Reading Passage 2 has ten paragraphs, A–J.

Which paragraph contains the following information?

Write the correct letter, A–J, in boxes 14–17 on your answer sheet.

• 14.reference to sea grasses’ stronger resistance to the salinity of the bay water
• 15.the importance of finding the real cause under the dispute
• 16.mention of the expensive solutions to the nitrogen dilemma
• 17.statistical data on ecological changes in coral area and species

Questions 18 – 21

Look at the following opinions (Questions 18–21) and the list of people below.

Match each opinion with the correct person, A, B or C.

Write the correct letter, A, B or C, in boxes 18–21 on your answer sheet.

NB You may use any letter more than once.

List of People 

A Bill Kruczynski

B Brian Lapointe

C Joseph Zieman

• 18.It is nutrients from sewage discharge, not from farmland, that cause the bay’s ecological problems.
• 19.Restoring water with a high nitrogen content would have more ecological side effects.
• 20.The drainage system in the Everglades actually contributes to the high salinity of the water in the bay.
• 21.Nearby farmland may be responsible for the high nitrogen levels.

Questions 22 – 26

Do the following statements agree with the claims of the writer in Reading Passage 2?

In boxes 22–26 on your answer sheet, write

YES if the statement agrees with the claims of the writer 

NO if the statement contradicts the claims of the writer

NOT GIVEN if it is impossible to say what the writer thinks about this

• 22.Everyone agrees with ‘pouring water into the sea seems harmless enough’ even in the Florida Bay area.
• 23.The water is injected with nitrogen as it passes through different types of crops.
• 24.Whatever the cause of the pollution, the Everglades restoration project will have a positive role to play.
• 25.Humans have changed Florida Bay where old image before the 1950s cannot be recalled.
• 26.Tourism makes an important contribution to the economy of the Florida Bay area.

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