第二十课

20 fresh water resources20淡水资源

There is a lot of water on the earth. How many fresh water resources are available for human use?地球上的水有很多，其中可供人类利用的淡水资源有多少?

Task card任务卡

Collect relevant information of freshwater resources.搜集淡水资源的相关 资料。

Activity process活动过程

● understand that water is the source of life.●了解水是生命之源。

Understand the freshwater resources on earth.了解地球上的淡水资源。

How much fresh water can be used on earth?地球上能用的淡水有多少呢?

There is little fresh water in the desert.沙漠中的淡水很少。

desert沙漠

glacier冰川

Do an experiment and experience it.做个实验体验一下吧。

I found that glaciers account for 2% of the total water volume of the earth我查到冰川占地球2总水量的.....

Mind map思维导图

1. 1. What is the total amount of water on earth?用什么表示地球上的总水量?

2. 2. How to express the total amount of fresh water resources?怎样表示淡水资源的总量?

3. 3.3. what means is the total available freshwater resource?3.用什么办法表示可利用的淡水资源的总量?

index card for files资料卡

Fresh water resources are composed of water in rivers and lakes, alpine snow, glaciers and groundwater, among which solid glaciers are difficult to use directly. At present, the fresh water resources that are easy to use are river water, fresh water lake water and part of shallow groundwater.淡水资源由江河湖泊中的水、高山积雪、冰川以及地下水等淡水水体组成，其中固体冰川较难直接利用。目前，人类较容易利用的淡水资源主要是河流水、淡水湖泊水以及一部分浅层地下水。

How to save water?●如何节约用水?

I mop the floor with washing water.我家用洗完衣服的水拖地。

Our community has a reclaimed water treatment system.我们小区有中水处理系统。

I also know我还知道.....

Development activities拓展活动

Be an electronic newspaper and a water-saving propagandist.做个电子报，当个节约用水的宣传员。

Unit evaluation单元评价

Knowledge paradise知识乐园

Fill in and say.填一填，说一说。

effect作用

Freshwater resources淡水资源

The water of the earth地球的水

Water type水体类型

Water saving methods节水方法

Sea land distribution, the sea area accounts for about 7 / 10海陆分布海洋面积约占7/10

The palace of undergraduate studies本科学殿堂

Access to information, understand the method of desalination.查阅资料，了解海水淡化的方法。

Reflection space反思空间

My harvest我的收获

● fresh water resources are precious.●淡水资源很珍贵。

I need to improve我需要改进的

The method of statistical land and sea distribution.●统计海陆分布的方法。

I want to continue to explore我想继续探究的

Will the land distribution of the earth change in the future?●未来地球上海陆分布情况会有变化吗?

                           Unit 6. Measurement tool第六单元  测量工具

"If want to be good, we must first."The use of tools drives human progress and social development. The balance can measure the mass of the object, the measuring cylinder can measure the volume of the liquid, and the hourglass can measure the time. Let's know and use these measurement tools together. “工欲善其事，必先利其器。”工具的使用推动着人类进步和社会发展。天平可以测量物体的质量，量筒可以测量液体的体积，沙漏可以计量时间。让我们一起认识、使用这些测量工具吧。