Farming the Sea
Farming the Sea
In some cool coastal waters, you can find farms with no fences, no tractors and no soil. The crop is kelp, a large brown seaweed, and the "fields" are long ropes floating just below the surface of the sea.
Kelp farming begins on land. In autumn, workers collect a few ripe pieces of wild kelp and place them in tanks of chilled seawater. The pieces release millions of tiny spores, which settle on spools of thin string. For about six weeks the young kelp grows on the string in the tanks, where it is safe from waves and hungry fish.
In early winter the string is wound around thicker ropes, which are then anchored out at sea between floating buoys. Kelp needs cold water rich in nutrients, and here it gets both. In good conditions the young plants grow quickly. By late spring, before the sea warms up, the ropes hang heavy with brown blades, some of them longer than an adult is tall, and the harvest begins.
Farmers like kelp for several reasons. It needs no fresh water and no fertiliser, and it does not have to be fed. As it grows, it takes in carbon dioxide from the seawater, and the ropes give small fish and crabs a place to shelter. Once harvested, the kelp can be eaten, dried for animal feed or turned into fertiliser for crops on land.
Many of these farms are still small, and storms can tear ropes loose. But some growers believe that the sea could one day help to feed far more people than it does now.
讲解示例 1
Where does the young kelp grow during its first six weeks?
- AA.
On thick ropes anchored between buoys
- BB.
On string in tanks of chilled seawater
- CC.
On rocks in shallow water near the shore
- DD.
In nets hanging beneath the farm boats
答案: B
答案:B(On string in tanks of chilled seawater)
第二段说孢子附着在细绳上,并且 for about six weeks the young kelp grows on the string in the tanks,而水箱里装的是冰冷的海水。
其他选项为什么不对
- 选项 A:粗绳是下一步,在初冬,也就是这六周之后才用上。
- 选项 C:文中从没提到岸边的岩石。
- 选项 D:文中没有出现渔网或养殖船。