Explain the meaning of soil retrogression while differentiating it from soil degradation. What are the major consequences of soil retrogression and degradation?

Soil retrogression and degradation are two important regressive evolution processes which take place due to loss of equilibrium of a stable soil.
Retrogression primarily occurs due to soil erosion. 
Whereas, Degradation is an evolution process which is different from natural evolution and is largely related to the local climate and vegetation. It is due to the replacement of primary plant communities (known as climax) by the secondary communities. This replacement in turn modifies the humus composition and amount, which will ultimately affect the formation of the soil. To bear in mind is that, degradation is largely associated with human activity. In simple word, soil degradation is any sort change or disturbance in the soil which is undesirable.
The consequences of both the processes are-

• Impacts the yield bearing capacity of the soil.
• A deterioration in water quality.
• Economic loss- this is a major negative externality.