问题 综合

阅读下列图文材料,回答问题。

珠江是我国南方的一条大河,西江是其主干,先后与北江、东江汇合,经珠江三角洲流入南海。珠江流域是我国农业较为发达的地区之一。西江上游红水河流域,山岭连绵,水力资源丰富而集中,它的梯级开发已被我国列为国家重点开发项目。近年来珠江口由于经常遭受咸潮的影响,水资源危机加剧。

1.珠江的水文特征是:_______________________________________________________。

2.近年来珠江河口常受海水入侵的威胁,据2012年1月6日中国之声《央广新闻》报道:“因受天文、水文、气象等因素的共同影响,特大咸潮袭击了珠江口地区。”根据所学知识,从天文、水文、气象因素分析珠江口地区此次遭受咸潮影响的原因。天文:_________,水文:______________,气象:________________________。

3.珠江流域的低山丘陵地区被认为是我国农业发展潜力最大的地区之一,试分析其原因。

_______________________________________________________________________________ 

4.从流域整治与开发的一般原则和任务出发,提出红水河流域综合整治与开发的建议。

_______________________________________________________________________________

答案

1、流量大,汛期长,含沙量较小,无结冰期,水能资源丰富

2、天文:正值农历月半,月球引潮力比较大的时期。水文:正值珠江水位比较低的枯水期。气象:正值珠江三角洲降水量少的时期。

3、气候湿热,光、热、水资源充足且大部分地区配合较好,农业品种丰富多样,植物生长速度快,更新能力强,具有较高的产品产出能力;丘陵地形有利于发展多种经营;中小河流众多,水源丰富;交通便利;农业历史长,技术先进;劳动力充足;市场潜力大。(任三点)

4、一是综合开发流域内的水资源、水能资源和锡、锰等金属矿产资源等,通过梯级开发红水河,控制洪水,提供丰富而稳定的水源,生产出大量廉价水电,改善通航条件;二是积极调整流域产业结构,充分利用水源条件,吸引资金投入发展高耗能的冶金、化工业,因地制宜,发展农、林、牧等多种农业经济;积极利用当地的自然条件,发展旅游服务业等促进产业升级,三是进一步加强水利实施建设;四是加强立法、执法,宣传教育保护水环境和生态环境。

单项选择题

How to protect children Web fans from unsuitable material on-line while encouraging them to use the Internet has long been discussed in the US.

For some parents, the Internet can seem like a jungle, filled with danger for their children. But jungles contain wonders as well as dangers and with good guides, some education, and a few precautions, the wilds of the Internet can be safely navigated. "Kids have to be on-line. If we tell our kids they can’t have access to the Internet, we’re cutting them off from their future, " said an expert.

Most kids have started to use search engines. Many of them are great for finding tons of interesting Internet sites, and they can also locate places where you might not want your kids to go. There are search engines designed just for kids. A certain software contains only sites that have been selected as safe. The most popular way to limit access would be to use what is known as a "content screener". But this can’t be wholly reliable, and the best thing parents can do is to talk to their kids and let them know what is OK or not OK to see or do on the Internet. Another way is that mum or dad is nearby when the child is surfing the Internet.

A few other tips

·Don’t put the PC in a child’s room but keep it in an area where mum or dad can keep an eye on things. That also makes the Internet more of a family activity.

·Ask your child what he or she has been doing and about any friends they make on-line.

·Tell your child not to give on-line strangers personal information, especially like address and phone number.

·And tell your children never to talk to anyone they meet on-line over the phone, send them anything, accept anything from them or agree to meet with them unless you go along.

The best way to protect children from improper material is()

A. to install (安装) a content screener on the computer

B. to buy some search engines for the children

C. to be nearby when they are surfing the Internet

D. to talk to the children and persuade them to tell right from wrong

单项选择题