I don't know if you're the type to worry about parmesan cheese daily, but did you know that its calcium content has declined by 70% compared with 1940? (Carl Pope of the Sierra Club said something similar in his lecture at Brown) or that you have to eat four carrots in 2006 to get the nutrition of a carrot in 1940? What a drag!
The SEER (Sustainable Ecological Earth Regeneration) Centre in Scotland, which undertook the first scientifically controlled field trials of soil remineralization, warned that unless vital nutrients and elements are placed back into the soil, Mother Earth is heading for an early and awful menopause. In fact, in the article, they actually refer to the soil being rendered "infertile" after chemical pesticides kill off vital algae, bacteria, fungi, etc. In fact, unusual weather (Mother Earth's having hot flashes!) is considered symptomatic of this global lurch toward infertility.
Check it out: http://www.nutraingredients.com/news/printNewsBis.asp?id=65812