我国保护大熊猫、褐马鸡、银杉、扬子鳄的自然保护区依次为（）。

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问题单项选择题

A.神农架、梵净山、肇庆、潘阳湖

B.高黎贡山、长白山、武夷山、扎龙

C.卧龙、庞泉沟、花坪、宣城

D.卧龙、神农架、武夷山、宣城

答案

参考答案：C

单项选择题

立体声广播制式，导频制是（）的一种。

A、和差制

B、极化调幅制

C、时间分割制

D、方向信号制

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问答题

Over the past 50 years, technology has changed the fishing industry dramatically. Today, the romantic, rugged individual fisherman is as threatened a species as the cod and tuna that once swarmed into his nets. This is the cumulative result of more sophisticated fishing gear, more powerful boat engines and a lack of regard for local fishing environments by the multinational enterprises that have come to dominate this business. There are about 30 million professional fishermen worldwide, but 50 percent of the fish caught at sea are captured by only 1 percent of the boats, notes Xavier Pastor, European vice-president for Oceans, a non-profit international advocacy group for the world’s oceans. "Industrialized fishing is leading to the disappearance of the small fisherman," he observes, with concomitant damage to both fish stock and to local economies and social structures. "Some fleets are just too big," Pastor says. "They are very efficient at taking the last fish in an area, then they move on to something else." This transformation has led to a global fishing crisis that is endangering most of the planet’s commercial stocks. Oceans reports that industrial fishing worldwide yields between 80 million and 100 million tons of fish, but it also generates 27 million tons of discards (marine organisms thrown back into the water after they have been caught), causing negative effects on the ecosystem that will last for decades. According to the Fond and Agricultural Organization, the commercial productivity of the oceans is at an all-time low, with 75 percent to 80 percent of the world’s major fisheries overexploited, fully exploited or recovering from depletion. "We are not anti-fishing," emphasizes Pastor. "Fishing is important. We Want to make sure that future generations can do the same."

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