原文：
A
Pouring water into the sea soundsharmless enough. But in Florida Bay, alarge and shallow section of the Gulf ofMexico that lies between the southern end of the Everglades (n.沼泽地）and the Florida Keys,it is proving highly controversial. That is because researchers are dividedover whether it will help or hinder the plants and animals that live in thebay.
B
What is at risk is the future of the bay’s extensive beds of sea grasses.These grow on the bay’s muddy floor and act as nurseries for the larvae (n.幼虫）of shrimps, lobstersand fish—many of them important sport and commercial fishing species. Also indanger is an impressive range of coral reefs that run the length of the FloridaKeys 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 reef, such ascrabs, turtles and nearly 600 species of fish.
C
What is causing such ecological change is a matter of much debate. And theanswer is of no small consequence. This is because the American government isplanning to devote $8 billion over the next 30 years to revitalizing theEverglades. Seasonal freshwater flows into the Everglades are to be restored inorder to improve the region’s health. But they will then run off into the bay.
D
Joseph Zeeman, a marine ecologist at the University of Virginia, thinks this isa good idea. He believes that a lack of freshwater in the bay is its mainproblem. The blame, he says, lies with a century of drainage (n.排水系统 ）in the Everglades aimed at turning the marshes intofarmland and areas for development. This has caused the flow of freshwater intoFlorida Bay to dwindle, making the water in the bay, overall, more saline.This, he argues, kills the sea grasses, and as these rot, nutrients arereleased that feed the microscopic plants and animals that live in the water.This, he says, is why the bay’s once crystal-clear waters often resemble a peasoup. And in a vicious circle, these turbid blooms block out sunlight, causingmore sea grasses to die and yet more turbidity.
E
Brian Lapointe, a marine scientist at the Harbour Branch Oceanographic Institutionat Fort Pierce in Florida, disagrees. He thinks sea grasses can tolerate much higher levels of salinity than the bay actually displays. Furthermore, he notes that, whenfreshwater flows through the Everglades were increased experimentally in the1990s, it led to massive plankton blooms. Freshwater running off fromwell-fertilized ( 肥沃 的 ）farmlands, he says,caused a fivefold rise in nitrogen levels in the bay. This was like pouringfuel on a fire. The result was mass mortality of sea grasses because ofincreased turbidity (n. 浑池度）from the plankton. Dr Lapointe adds that, because coralsthrive only in waters where nutrient levels are low, restoring freshwater richin nitrogen will do more damage to the reef.
F
It is a plausible theory. The water flowing off crops that are grown onthe750,000 acres of heavily fertilized farmland on the northern edge of theEverglades is rich in nitrogen, half of which ends up in the bay. But BillKruczynski, of Amir ice’s Envier on mental Protection Agency, isconvinced that nitrogen from farmlands is not the chief problem. Some coralreefs well away from any nitrogen pollution are dying and, curiously, a few arethriving. Dr Kruczynski thinks that increased nutrients arriving from localsewage discharges from the thousands of cesspits (污水坑）along the Florida Keysare part of the problem.
G
Suchclaims and counterclaims make the impact of the restoration plandifficultto predict. If increased salinity is the main problem, the bay’secology will benefit from the Everglades restoration project. If, however,nitrogen is the problem, increasing the flow of freshwater could mate mattersmuch worse.
H
If this second hypothesis proves correct, the cure is to remove nitrogen fromfarmland or sewage discharges (n.卸下， 解 雇 ）, or perhaps both. Neither will be easy. Man-made wetlands,at present being built to reduce phosphate (磷化物) run off into the bay—also from fertilisers—would need analgal culture (a sort of contained algal bloom) added to them to deal withdischarges from farmlands. That would be costly. So too would be the replacementof cesspits with proper sewerage—one estimate puts the cost at $650m. Eitherway, it is clear that when, on December 1st, 3,000 square miles of sea aroundthe reef are designated as a “protective zone”by the deputy secretary ofcommerce, Sam Bodman, this will do nothing to protect the reef from pollution.
I
Some argue, though, that there is a more fundamental flaw in the plans forthe bay: the very idea of returning it to a Utopian ideal before man wroughthis damage. Nobody knows what Florida Bay was like before the 1950s, whenengineers cut the largest canals in the Everglades and took most of the wateraway. Dr Kruczynski suspects it was more like an estuary (江海口）The bay that manypeople wish to re-create could have been nothing more than a changing phase inthe bay’s history.
J
These arguments do not merely threaten to create ecological problems but economic ones as well. Theeconomy of the Florida Keys depends on tourism—the local tourist industry hasan annual turnover of $2.5 billion. People come for fishing-boat trips, formanatee watching, or for scuba diving and snorkeling (浮潜）to view the exoticallycoloured corals. If the plan to restore the Everglades makes problems in thebay and the reef worse, it could prove a very expensive mistake.
Questions 1-4.................................................................................
The reading Passage has seven paragraphs A-J.
Which paragraph contains the following information?
Write the correct letter A-J, in boxes 1-4 on your answer sheet.
NB You may use any letter more than once.
1 See grass turned to be more resistant to the saline water level in the Bay.
2 Mentioned of a costly project which may be futile.
3 Financial problems raised upon de-phosphate from fertilizer.
4 An alarming fact that both the coral area and species greatly dropped inFlorida
keys
Questions 5-8.................................................................................
Use the information in the passage to match the people (listed A-C) withopinions ordeeds below. Write the appropriate letters A-C in boxes 5-8 on youranswer sheet.
A Bill Kruczynski
B Brian Lapointe
C Joseph Zieman
5 Drainage system in everglades actually results in high salty water inthe bay.
6 Restoring water high in nitrogen level will make more ecological side effect
7 High nitrogen levels may be caused by the nearby farmland.
8 Released sewage instead of agricultural area increase the level of Nitrogen.
Questions 9-13...............................................................................
Do the following statements agree with the information given in Reading Passage2
In boxes 9-13 on your answer sheet, write
TRUE if the sataement agrees with the information
FALSE if the statement contradicts the information
NOT GIVEN if there is no information on this
9 Everyone agree with “pouring water into sea is harmless enough”even in
Florida Bay area.
10 Nitrogen was poured in from different types of crops as water flowsthrough.
11 Everglade restoration project can be effective regardless thecause of the pollution.
12 Human has changed Florida Bay where old image is unrecalled.
13 Tourism contributes fundamentally to the Florida Bay area.
参考答案：
1 .E 2. C 3. H 4. B 5.C 6.B
7 .B 8 .A 9 .FALSE 10. NOT GIVEN
11. FALSE 12 .TRUE 13 .TRUE
Passage 3:儿童符号行为研究
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发表于 2021-1-19 11:29:46
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