问题 问答题 简答题

土壤升温措施主要有

答案

参考答案:

(1)排水

排水后土壤的水气比减小,从而其热容量和导热率都随之减小,在有太阳辐射的条件下,升温速度加快;土面蒸发减弱,于是因水分蒸发吸热而造成的热量损失减少。

(2)中耕松土

中耕松土后土壤孔隙度增大,水气比减小,热容量和导热率降低,升温速度加快。

(3)向阳作垄

阳坡垂直照射时间长,土温较高。

(4)施有机肥

有机质增多,土壤颜色加深,吸热性增强;有机质增加后,土壤孔隙度增加,热容量和导热率降低,在有太阳辐射的条件下,升温速度加快;有机质分解可以释放生物热。

阅读理解

阅读理解。

     Can plants eat people? Probably not,but there are many plants that eat meat. Some of them are big.

And they can eat small animals. One famous meat-eating plant is the Venus flytrap(捕蝇草).

The Venus flytrap is a very strange plant. It grows in dry parts of the United States. Its leaves are like the

pages of a book. They can open and close very quickly. Inside the leaves,there are three small hairs. If a

fly touches one of the hairs,the leaf closes quickly. The fly cannot get out. In about half an hour,the leaf

presses the fly until it is dead. Then,the plant covers the fly. Slowly,the plant eats the fly.

     Why do plants do it? Most plants get what they need from the sun,the air,and the ground. In some

places,the ground is very poor. It doesn't have all these important things,especially nitrogen(氮). Animal

meat has a lot of nitrogen,so some plants eat meat to get what they need. Let's hope that some of the

bigger plants don't get the same idea !

1. The Venus flytrap is a kind of_______.

A. plant

B. animal

C. food

D. meat

2. The Venus flytrap grows in_______.

A. most parts of the world

B. some parts of Africa

C. dry parts of the United States

D. wet parts of England

3. From the passage,we learn that_______.

A. all plants can eat people

B. all plants can eat animals

C. some plants can eat people

D. some plants can eat animals

4. The underlined word“presses”probably means_______ in Chinese.

A. 挤压

B. 关上

C. 打开

D. 松开

5. —Why do some plants eat animal meat? 

    —Because_______.

A. plants are dangerous to animals

B. animals are dangerous to plants

C. plants want to get what they need from animal meat

D. plants want to protect themselves against animals

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