Save Our Soils: Finding ways to stop erosion
FAO launched Soil erosion: the greatest challenge for sustainable soil management, at the Global Symposium on Soil Erosion symposium.
The 100-page book, with Dan Pennock, professor at Canada's University of Saskatchewan as its lead author, takes stock of the current state of knowledge regarding soil erosion. More research has been published on the topic in the past three years than in the entire 20th century.
While knowledge of how soil erosion occurs and how to control it is firmly established, more research is needed on how to measure soil loss rates and budget for measures to reduce them - remain under debate. Indeed, there is disagreement over whether erosion turns soil into a source or sink for carbon emissions, as well as rival formulas to assess the relationship between the size of raindrop splashes and the likelihood that they detach soil particles and remove them from the landscape.
Still, evidence is clear that soil erosion rates on conventionally ploughed agricultural land or intensively grazed pasturelands are notably greater than erosion under native vegetation - and much higher than soil formation rates - implying that we are depleting a non-renewable resource.