Soil conservation done on hill slopes _____________

Cutting down of trees____________________

Human activities that increase soil erosion include

A wall or fence of earth or stone built to prevent a river flooding an area is known as

Soil is mostly conserved by _______

The Hwang Ho river which changes its course every year is in _________

Plants and trees hold soil together with the help of their

Farmers grow crops like grass and creepers after a harvest and before raising the next crop. These are known as ____________

River Hwang Ho is also known as __________________.