Medieval water mill is a crime of destroying ecological balance

In the article published in Scientific Reports, the ecologists at Radboud University, Netherlands, confirmed the massive construction of medieval watermills that made salmon almost disappear completely. in Northern European rivers. And this negatively affects wild nature.

Atlantic salmon usually lay eggs in rivers and are a popular food source. But today, salmon rarely enter the eggs in the Rheine and Northern European rivers.

Until recently, it was often thought that salmon disappearing due to pollutants discharged directly into rivers and lakes when industrial production developed in the late nineteenth century.

The medieval water mill made salmon almost disappear in Northern European rivers.

But researcher Rob Lenders confirmed that salmon completely stopped spawning in the Rheine River since the Middle Ages. And the cause is the water mill.

Based on the catch data of German and Dutch fishermen, the authors of the study determined that salmon production decreased between 1200 and 1400 years. The water mill is massively built. At the same time, there are also dams that prevent the movement of salmon.

More importantly, the dams have changed the flow, the upstream of the river accumulates a lot of mud and sand while young salmon are usually eggs on rocky ground.

Scientists firmly believe that the watermills made salmon disappear , rather than over-hunting. In other regions like Scotland and Scandinavian countries, hunting also thrives but does not affect salmon flocks.

The design of watermills with other rotary wheels does not require dams, so it does not affect the ecosystems of rivers as much as it did in the Netherlands and Germany.

Ecologist Rob Lenders asserts that salmon swims into rivers every year carrying hundreds of tons of nutrients from the ocean to the surrounding river areas. Also because there is no salmon left, the number of wolf, bear and eagle heads also decreases.

Reference: ru.nl