Slash and Burn") to free up land for farming has enormous implications across the globe. This week NASA has photographed images of massive fires across North Korea, which are most likely farmers burning land for this purpose.
The consequences of slash-and-burn techniques to ecosystems are almost always deleterious when practiced on a large scale. The principal vulnerability is the nutrient-poor soil. When biomass is extracted even for one harvest of wood or charcoal, the residual soil value is heavily diminished for further growth of any type of vegetation. The short term negetive impact on air quality is obvious as well.
There is documented evidence of mass starvation in North Korea, probably because of a lack of suitable arable regions for crop production. Korea's best agricultural soils are alluvial and are found in river valleys and coastal plains. Even these, however, tend to be somewhat infertile and sandy and require heavy fertilizing. Soils in the mountains are generally thin and suitable only for cultivation by the slash-and-burn technique.
Richard Wottrich, Blog Editor