FAO Soils Bulletins

#1

https://www.fao.org/soils-portal/resources/soils-bulletins/fr/

free pdf downloads of many.

See especially #80, #77, #75.

#2

Here is #60 “Soil conservation for small farmers in the humid tropics”, 1989

Soil Conservation for Small Farmers in the Humid Tropics Sheng FAO 1989.pdf (3.3 MB)