Heavy downpours last month in Rhode Island led to widespread flooding, causin

       Heavy downpours last month in Rhode Island led to widespread flooding, causing millions of dollars in property damage and leaving thousands homeless. The flood waters also poured vast amounts of raw sewage(未经净化的污水) into the rivers and streams that flow into Narragansett Bay.

       It sounds like the makings of an environmental nightmare. But in fact it’s just the opposite. To scientists’ delight. The sewage-loaded floodwaters have caused a well-timed growth of phytoplankton. The microscopic creatures that form the foundation of marine(海洋的) food chains. With more food available for fish. Clams and other sea creatures. The bay’s fisheries industry is expected to benefit.

       In decades past. Narragansett Bay typically experienced a late winter early spring algal(海藻) bloom that fed creatures up and down the water column. But in recent years, the waters of Narragansen Bay warmed greatly, meriting this seasonal event.

       Mark Berman, an oceanographer with the Nationa. Marine Fishertes Service. Said the flood seemed to have sent the bay back in its normal state.

       However, local, mutate and federal officials in Rhode Island leave been batting other algal blooms that, by contrast, are causing widespread harm to the Narragansett Bay ecosystem. During summer months, sewage and agricultural runnel flows into the bay. Causing large blooms. But inseam of becoming food for sea creatures, much of the phytoplankton is consumed by bacteria, which grow last in the warmer waters. The rapid bacteria growth leads to hypoxia decrease of oxygen in the water that can cause large fish tools. One such die-off occurred in 2003. when millions of oxygen-starved fish washed up on the belches of Narragansett Bay.

       The flood’s positive impact will probably be a one-time event, Mr Berman said. Mcanwhile efforts to curb the harmhl summer honors continue; in 2003. for instance, Providence completed a $359 million sewage tonal under the city designated to reduce the polluted storm overflow into Narragansett Bay.

71.Scientists believe that the row sewage flowing into the bay will           .

       A.pollute the island’s environ mean   B.cause lots of property damage

       C.increase the fisheries production     D.destroy the food chains in the bay

72.The potential benefit of fisherics industry rclics on the           .

       A.warm temperatures of the bay.       B.growth of phytoplankton

       C.large summer alga blooms      D.consumption of oxygen by beaters

73.People struggle against the summer blooms because they will          .

       A.pollute the local natural environment

       B.increase the prcducmon of fishery industry

       C.cause large fish kills of the bay indirectly

       D.provide too much food ior sea creatures

74.It can be inferred that         .

       A.money spent on the summer blooms has been wasted

       B.the government is inverting to promote the local fisheries

       C.research of accanology should he encouraged

       D.she raw sewage impacts are currently con radiator

75.The underlined word “carb” n the hast postage can be defined as “          ”.

       A.control     B.consume   C.cause D.cure

答案

71—75CBCDA

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