How can we prevent land erosion?

In class today my teacher was saying how planting a native plant along a river bank can help to prevent land erosion, but how??

Thanks for your help and explanations=)

The root system in the plants can help provide anchors, anchoring both the top soil, the clay level which can be quite heavy, and the other type of weathering. In those situations where there has been deforestation or logging, it becomes quite vulnerable with the fact that root system has established a rooting system or an anchoring system, and with them yanked out it also creates land disturbances such as erosion etc.

Another factor is that wind can cause erosion as well as rain and run off, and if there are plants, it can help shelter some of this from occurring as well.

I hope that this helps you understand this.

preserving topsoil by planting plants and other methods

Roots hold the soil and make it more resistant to erosion.

we cant prevent land erosion.

We can only minimise the effects of erosion. However temporarily stopping erosion in one place, often increases erosion elsewhere. Nevertheless planting plants with large root systems (such as marram grass) helps to hold the soil together and therefore strengthens the banks of the river.