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(单词翻译:双击或拖选)
In the oysters2 were raised in much the same way as dirt farmers raised tomatoes- by transplanting them. First, farmers selected the oyster1 bed, cleared the bottom of old shells and other debris3, then scattered4 clean shells about. Next, they "planted" fertilized5 oyster eggs, which within two or three weeks hatched into larvae6. The larvae drifted until they attached themselves to the clean shells on the bottom. There they remained and in time grew into baby oysters called seed or spat7. The spat grew larger by drawing in seawater from which they derived8 microscopic9 particles of food. Before long, farmers gathered the baby oysters, transplanted them once more into another body of water to fatten10 them up.
Until recently the supply of wild oysters and those crudely farmed were more than enough to satisfy people's needs. But today the delectable11 seafood12 is no longer available in abundance. The problem has become so serious that some oyster beds have vanished entirely13.
Fortunately, as far back as the early 1900's marine14 biologists realized that if new measures were not taken, oysters would become extinct or at best a luxury food. So they set up well-equipped hatcheries and went to work. But they did not have the proper equipment or the skill to handle the eggs. They did not know when, what, and how to feed the larvae. And they knew little about the predators15 that attack and eat baby oysters by the millions. They failed, but they doggedly16 kept at it. Finally, in the 1940's a significant breakthrough was made.
The marine biologists discovered that by raising the temperature of the water, they could induce oysters to spawn17 not only in the summer but also in the fall, winter, and spring. Later they developed a technique for feeding the larvae and rearing them to spat. Going still further, they succeeded in breeding new strains that were resistant18 to diseases, grew faster and larger, and flourished in water of different salinities and temperatures. In addition, the cultivated oysters tasted better!
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1 oyster | |
n.牡蛎;沉默寡言的人 | |
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2 oysters | |
牡蛎( oyster的名词复数 ) | |
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3 debris | |
n.瓦砾堆,废墟,碎片 | |
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4 scattered | |
adj.分散的,稀疏的;散步的;疏疏落落的 | |
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5 Fertilized | |
v.施肥( fertilize的过去式和过去分词 ) | |
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6 larvae | |
n.幼虫 | |
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7 spat | |
n.口角,掌击;v.发出呼噜呼噜声 | |
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8 derived | |
vi.起源;由来;衍生;导出v.得到( derive的过去式和过去分词 );(从…中)得到获得;源于;(从…中)提取 | |
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9 microscopic | |
adj.微小的,细微的,极小的,显微的 | |
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10 fatten | |
v.使肥,变肥 | |
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11 delectable | |
adj.使人愉快的;美味的 | |
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12 seafood | |
n.海产食品,海味,海鲜 | |
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13 entirely | |
ad.全部地,完整地;完全地,彻底地 | |
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14 marine | |
adj.海的;海生的;航海的;海事的;n.水兵 | |
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15 predators | |
n.食肉动物( predator的名词复数 );奴役他人者(尤指在财务或性关系方面) | |
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16 doggedly | |
adv.顽强地,固执地 | |
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17 spawn | |
n.卵,产物,后代,结果;vt.产卵,种菌丝于,产生,造成;vi.产卵,大量生产 | |
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18 resistant | |
adj.(to)抵抗的,有抵抗力的 | |
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