http://saveoursoils.com/userfiles/downloads/1351255687-Chang...
Conclusion: We suggest that any real declines are generally most easily explained by changes in cultivated varieties between 1950 and 1999, in which there may be trade-offs between yield and nutrient content.
Worth noting there is no use of the phrase "soil depletion".
I take issue with the comment near the end:
> Also, foregoing pesticides and fertilizers in favor of organic growing methods is good for the soil, the produce and its consumers. Those who want to get the most nutritious fruits and vegetables should buy regularly from local organic farmers.
To my knowledge, organic farming employs just as much, if not more, pesticide and fertilizer. But there are regulations determining which products are allowed to be classed as "organic". Such regulations can be somewhat arbitrary; for example, a lot of so-called organic produce is the product of radiation-induced mutation [0].