Problems:

Despite its obvious suitability to certain environment, shifting cultivation is a very primitive form of agriculture that, at best, offers only a low level of subsistence to those groups that practice it. Consequently, in the rapidly changing world of the 20th century.

Basically, the many problems confronting this system of agriculture stem either from:

(a) increasing population; or

(b) the impact of Europeans.

To a great extent, of course, these two influences are interrelated because the former is largely due to the latter.