Five indices are used to investigate the whole picture of a river environment, including the river water, the living things, the scenery, and its use in our daily lives. Each index has three to five items (called separate indicators) used to investigate the river condition.
Evaluate each separate indicator on a scale of 3 to 1 by observing the river conditions.
If possible, write the reasons why you chose your ranking.
You can start with any indicator that seems appropriate.

2. Rich in plants and animals (Biological diversity)

This represents the variety and quantity of plants and animals in the water environment.

*For more detailed information,
please refer to the Ministry of the Environment manual "Let's go to a river together! (PDF)".


(1) Plants on the side of the river

Are plants growing along the riverside?

Investigate the plants on the side of the river. Rich plants provide a place for many animals to live. Observe the condition of the plants along the riverside and the riverbank at the investigation site.

Abundant variety of plants (Scale 3)

Plants are here and there (Scale 2)

No plants (Scale 1)


(2) Birds and bird habitats

Are there birds?

Investigate the habitats available for birds and small living things to make nests, find food, and rest in the river and along the riverside. Observe whether there are many habitats for living things at the investigation site.

There are many water birds and bird habitats (Scale 3)

There are not many birds or habitats (Scale 2)

There are no birds or habitats (Scale 1)


(3) Fish and fish habitats

Are there fish?

Fish habitats are closely related to the water environment. When there are various types of habitats, various types of fish can live there. Because finding a fish is not easy, try to find their habitats. Ornamental fish, such as colored carps, should be excluded from your investigation.

There are many fish and their habitats (Scale 3)

There are not many fish or habitats (Scale 2)

There are no fish or habitats (Scale 1)


(4) Living things in the riverbed

Are there living things on the bottom of the river?

The conditions of the riverbed and of small organisms living there tell us about the water quality. Observe the riverbed conditions and the types of organisms.

Sand and stones are slightly covered with algae, insects can be found (Scale 3)

The surfaces of stones are slimy in the presence of many algae (Scale 2)

The bottom of the river looks dark, and no algae or insects can be found (Scale 1)

All photos shown here are of rivers in Japan. When the number of overseas surveys increases in the future, we plan to present photos of overseas rivers here. We hope that with your cooperation, surveys will be conducted widely around the world.

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Please feel free to contact us if you have any questions about how to use "Mizube Go!" or how to use it for environmental learning.