Dear student,
Yes, a man living at a particular place can work particularly only at his native place and surrounding area on a regular basis to improve the quality of the soil. It is not possible for a man to work on soils of different places at the same time. Many factors are responsible such as geographical isolation between two places, knowledge about the soils of different places, labour work, etc.
But,if humans can work at their respective places to improve the soil quality of that particular area then overall the soil quality of a country could be improved.
Regards.