乌伦古源有“戈壁大海”之称,是新疆的第二大渔业基地。其湖鱼品质优良,但生长缓慢,产量较低,市场上供不应求,价格昂贵。狗鱼是该湖最名贵的鱼种之一,自1991年引入池沼公鱼后,狗鱼数量不断下降,濒临灭绝,后来池沼公鱼被清理出来,狗鱼数量才得到恢复。读图完成下列各题。

【小题1】乌伦古湖中鱼类生产缓慢的主要原因是( )
| A.水温较低[Failed to download image : http://192.168.0.10:8086/QBM/2018/7/1/1979045564825600/1981703493943296/STEM/3a993b9c6bd74c0dacd84a525117714d.png] | B.光照不足[Failed to download image : http://192.168.0.10:8086/QBM/2018/7/1/1979045564825600/1981703493943296/STEM/3a993b9c6bd74c0dacd84a525117714d.png] | C.水质较差[Failed to download image : http://192.168.0.10:8086/QBM/2018/7/1/1979045564825600/1981703493943296/STEM/3a993b9c6bd74c0dacd84a525117714d.png] | D.水量较小 |
【小题2】乌伦古湖引入池沼公鱼后,狗鱼数量下降的主要原因可能是数量众多的池沼公鱼( )
| A.分抢了狗鱼饵料食物[Failed to download image : http://192.168.0.10:8086/QBM/2018/7/1/1979045564825600/1981703493943296/STEM/77d59a5fb9fe477299469ba0641c6b39.png] | B.影响了狗鱼后代繁育 |
| C.挤占了狗鱼活动空间 [Failed to download image : http://192.168.0.10:8086/QBM/2018/7/1/1979045564825600/1981703493943296/STEM/77d59a5fb9fe477299469ba0641c6b39.png] | D.使湖水严重富营养化 |