曰韩免费_91久久精品国产亚洲_一区二区成人影院_九一视频在线免费观看_91国视频_亚洲成人中文在线

2023考研阅读资料经典美文33

雕龙文库 分享 时间: 收藏本文

2023考研阅读资料经典美文33

  33 Plankton浮游生物. / plж `plжktэn/

  Scattered through the seas of the world are billions of tons of small plants and animals called plankton. Most of these plants and animals are too small for the human eye to see. They drift about lazily with the currents, providing a basic food for many larger animals.

  Plankton has been described as the equivalent of the grasses that grow on the dry land continents, and the comparison is an appropriate one. In potential food value, however, plankton far outweighs that of the land grasses. One scientist has estimated that while grasses of the world produce about 49 billion tons of valuable carbohydrates each year, the seas plankton generates more than twice as much.

  Despite its enormous food potential, little effect was made until recently to farm plankton as we farm grasses on land. Now marine scientists have at last begun to study this possibility, especially as the seas resources loom even more important as a means of feeding an expanding world population.

  No one yet has seriously suggested that plankton-burgers may soon become popular around the world. As a possible farmed supplementary food source, however, plankton is gaining considerable interest among marine scientists.

  One type of plankton that seems to have great harvest possibilities is a tiny shrimp-like creature called krill. Growing to two or three inches long, krill provides the major food for the great blue whale, the largest animal to ever inhabit the Earth. Realizing that this whale may grow to 100 feet and weigh 150 tons at maturity, it is not surprising that each one devours more than one ton of krill daily.

  

  33 Plankton浮游生物. / plж `plжktэn/

  Scattered through the seas of the world are billions of tons of small plants and animals called plankton. Most of these plants and animals are too small for the human eye to see. They drift about lazily with the currents, providing a basic food for many larger animals.

  Plankton has been described as the equivalent of the grasses that grow on the dry land continents, and the comparison is an appropriate one. In potential food value, however, plankton far outweighs that of the land grasses. One scientist has estimated that while grasses of the world produce about 49 billion tons of valuable carbohydrates each year, the seas plankton generates more than twice as much.

  Despite its enormous food potential, little effect was made until recently to farm plankton as we farm grasses on land. Now marine scientists have at last begun to study this possibility, especially as the seas resources loom even more important as a means of feeding an expanding world population.

  No one yet has seriously suggested that plankton-burgers may soon become popular around the world. As a possible farmed supplementary food source, however, plankton is gaining considerable interest among marine scientists.

  One type of plankton that seems to have great harvest possibilities is a tiny shrimp-like creature called krill. Growing to two or three inches long, krill provides the major food for the great blue whale, the largest animal to ever inhabit the Earth. Realizing that this whale may grow to 100 feet and weigh 150 tons at maturity, it is not surprising that each one devours more than one ton of krill daily.

  

主站蜘蛛池模板: 久久精品国产99国产 | 成人小视频在线免费观看 | 欧美成人香蕉网在线观看 | 色翁荡息又大又硬又粗又视频软件 | 国产国产人免费观看在线视频 | 国产亚洲欧洲人人网 | 日日狠狠久久8888偷偷色 | 国产午夜福利视频在线观看 | 欧美观看一级毛片 | 国产真人做爰毛片视频直播 | 日韩日韩日韩日韩 | 麻豆精品a在线观看 | 大陆国语对白国产av片 | 亚洲精品6久久久久中文字幕 | 欧区一欧区二欧区三免费 | 亚洲欧美日韩一区 | 久久大香伊蕉在人线国产昨爱 | 久久久久久爱 | 亚洲男人天堂视频 | 久久精品人人爽人人爽 | 国产亚洲在线观看 | 内射爽无广熟女亚洲 | 日韩吃奶摸下aa片免费观看 | 五月婷之久久综合丝袜美腿 | 国产精品视频在线免费观看 | 中文无码久久精品 | 久久精品视频6 | 免费激情小视频 | 又爽又黄又无遮挡的激情视频 | 国内自拍偷拍视频 | 国产精品自在线拍国产 | 国产亚洲精品sese在线播放 | 中文字幕人成人乱码亚洲电影 | 欧美性生活在线视频 | 亚洲欧美日韩国产手机在线 | 亚洲日韩中文字幕在线播放 | 亚洲精品国产精品国自产观看 | 看毛片网站 | 又粗又硬又大又爽免费视频播放 | jizz日本女人 | 两个人看的www高清观看 |