In my previous post (Soil Erosion Rises Again!) I noted a recent spike in interest in erosion and soil conservation, following previous ones in the 1930s and 1980s. One manifestation is the work of Frans Kwaad, a Dutch physical geographer, who has reinvigorated discussion of the relative onsite and offsite costs of erosion.

Onsite (economic) costs are generally related to declines in crop or grazing productivity, or the loss or degradation of economically productive land. Offsite costs are associated with pollution and infrastructure damage associated with the deposition or delivery of eroded sediment, habitat damage or destruction, nuisance costs of removal of deposited sediment, etc. Kwaad’s work-in-progress synthesizes a number of studies and data sources, and on-balance indicates that off-site costs are greater.

Cleaning up eroded soil after a storm in the Netherlands (F. Kwaad photo).

In the 1930s, the Dust Bowl and the legacy of massive post-Civil War cut-out-and-get-out logging and, particularly in the south, of what amounts to shifting cultivation brought a soil erosion crisis to the attention of the USA and the world. In the 1980s, a realization that problematic erosion persists despite great improvements in soil conservation and a heightened concerned with nonpoint source pollution from agriculture brought renewed attention to erosion, this time focused particularly on off-site impacts. On-site impacts of soil erosion are the environmental degradation and lost productivity due to soil loss, while off-site impacts are related to pollution and costs associated with where the soil ends up. Now, we are at it again, with another wave of attention to soil erosion.  

Eroded farmland in Alabama, 1930s (WPA photo by Arthur Rothstein).