题目内容
【题目】石漠化已成为西南地区头号生态灾难，治理石漠化刻不容缓。下列属于石质荒漠化形成的条件有（ ）
①高温多雨的气候 ②可溶性岩石广布 ③昼夜温差大 ④地势低洼，易于积水
A. ①② B. ①③ C. ②③ D. ③④
【答案】A
【解析】
石灰岩地层是形成喀斯特地形的基础，它们是远古时代海洋沉积物形成的地层，这些石灰岩地层，陆续上升并出露地表后，经过复杂而漫长的外力作用，逐渐形成为喀斯特地形。
自然因素是石漠化形成的基础条件。①岩溶地区丰富的碳酸盐岩具有易淋溶、成土慢的特点，是石漠化形成的物质基础。山高坡陡，②气候温暖、雨水丰沛而集中，为石漠化形成提供了侵蚀动力和溶蚀条件。此外，岩溶地区人口密度大，地区经济贫困，群众生态意识淡薄，各种不合理的土地资源开发活动频繁，导致土地石漠化。故选A。
【题目】阅读短文，根据所读内容在文章后表格中的空格里填人一个最恰当的单词。
We dislike too hot days. Luckily, we have air conditioners and fridges. How did Chinese people stay cool in the hot season before they have air conditioners and fridges?
The most common way Chinese people in the past kept cool was to use fans. Many fans had poems or drawings on them.
Beginning in the Sui dynasty(朝代), Chinese people started to use porcelain pillows(瓷枕). These pillows felt cool, so people could sleep well on them.
People in old times didn't have fridges to make ice. Instead, they collected ice in winter and kept it underground, sometimes in wells(井). When summer came, they got the ice out and put it in their living rooms to cool them down.
Rich people and members of the king family had more expensive ways to keep cool. As early as the Han dynasty, some people used a tool(工具) like modern electrical fans. It was made of a wheel(轮子) and some fan blades(叶片). A person would pull a rope to make the wheel spin(转) and then the blades would spin around fast.
In the Tang dynasty, people found a way to make their whole house cool. They built their houses next to the water, used some machines to carry water to the top of the house, and made it flow down from the eaves(屋檐). This man-made waterfall brought cool air into the house.
How people kept cool in the past | |
Different 【1】 in different times | Fans: It was very common for people to use fans with 【2】 or drawings on them. |
Porcelain pillows: In the Sui dynasty, 【3】people began to sleep on porcelain pillows【4】 these pillows were cool. | |
Ice: In winter, ice was collected and stored, and then in 【5】 , people got the ice out and put it in houses to make the temperature 【6】 | |
【7】 fans: In the Han dynasty, a tool like modern electrical fans was used by only a small number of people, for it was【8】 | |
Water: In the 【9】 dynasty, people kept their houses cool by making 【10】 waterfalls. | |