海    底    世    界   

 你    可    知    道   , 大    海    的    深    处    是    怎    样    的   ?
 海    面    上    波    涛    澎    湃    的    时    候   , 海    底    依    然    很    宁    静   。 最    大    的    风    浪   , 也    只    能    影    响    到    海    面    以    下    几    十    米    深   。 阳    光    很    难    射    进    深    海   , 水    越    深    光    线    越    暗   , 五    百    米    以    下    就    全    黑    了   。 在    这    一    片    黑    暗    的    深    海    里   , 却    有    许    多    光    点    像    闪    烁    的    星    星   , 那    是    有    发    光    器    官    的    深    水    鱼    在    游    动   
 海    底    是    否    没    有    一    点    儿    声    音    呢   ? 不    是    的   。 海    底    的    动    物    常    常    在    窃    窃    私    语   。 你    用    水    中    听    音    器    一    听   , 就    能    听    见    各    种    声    音   :  有    的    像    蜜    蜂    一    样    嗡    嗡   , 有    的    像    小    鸟    一    样    啾    啾   , 有    的    像    小    狗    一    样    汪    汪   , 还    有    的    好    像    在    打    鼾   …… 它    们    吃    东    西    的    时    候    发    出    一    种    声    音   , 行    进    的    时    候    发    出    另    一    种    声    音   , 遇    到    危    险    还    会    发    出    警    报   
 海    里    的    动    物   , 各    有    各    的    活    动    方    法   。 海    参    靠    肌    肉    伸    缩    爬    行   , 每    小    时    只    能    前    进    四    米   。 有    一    种    鱼    身    体    像    梭    子   , 每    小    时    能    游    几    十    千    米   , 攻    击    其    他    动    物    的    时    候   , 比    普    通    的    火    车    还    快   。 乌     贼    和    章    鱼    能    突    然    向    前    方    喷    水   , 利    用    水    的    反    推    力    迅    速    后    退   。 还    有    些    贝    类    自    己    不    动   , 却    能    巴    在    轮    船    底    下    作    免    费    的    长    途    旅    行   
 本    文    作    者    石    友   , 选    作    课    文    时    有    改    动   
 海    底    的    植    物    差    异    也    很    大   。 它    们    的    色    彩    多    种    多    样   , 有    褐    色    的   , 有    紫    色    的   , 还    有    红    色    的   。 最    大    的    海    藻    长    达    二    三    百    米   。 最    小    的    单    细    胞    海    藻   , 要    用    显    微    镜    才    能    看    清    楚   
 海    底    蕴    藏    着    丰    富    的    煤   、 铁   、 石    油    和    天    然    气   , 还    有    陆    地     上    储    量    很    少    的    稀    有    金    属   
 海    底    真    是    个    景    色    奇    异   、 物    产    丰    富    的    世    界   

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