Dirt Poor: Have Fruits and Vegetables Become Less Nuritious? EarthTalk (registered trademark of E - The Environmental Magazine), written and edited by Roddy Scheer & Doug Moss, published in Scientific American -- 27 Apr 2011 "Because of soil depletion, crops grown decades ago were much richer in vitamins and minerals than the varieties most of us get today"
Earth Matters: Tackling the Climate Crisis from the Ground Up (See esp. Box 2 & Box 3) GRAIN -- Oct 2009
How Industrial Ag is Making the Soil -- and Us -- Unhealthy Hannah Bewsey and Katherine Paul, Organic Consumers Association -- 11 Sep 2014 "Does an apple a day really keep the doctor away? Not anymore, according to soil health experts—unless the apple comes from a tree grown in healthy, organic soil."
Soil Biology Primer Elaine R. Ingham, Andrew R. Moldenke, Clive A. Edwards, Natural Resources Conservation Service, USDA -- 2000 On-line resources related to basic soil biology, soil health & management, the soil food web and more that support healthy plants and crops.
Still No Free Lunch: Nutrient Levels in US Food Supply Eroded by Pursuit of High Yields Brian Halweil, The Organic Center -- Sep 2007
That First Step: Organic Food and a Healthier Future Christine McCullum-Gomez, Charles benbrook, Richard Theurer, The Organic Center -- Mar 2009
What Happened to the Essential Nutrients in Our Food Courtey White, Mother Earth News -- Jul 2014 "Everyone needs vitamins and minerals like potassium, calcium, magnesium and others to stay strong and healthy. Find out why these essential nutrients have decreased in our food and how we can get them back."
With the Grain: A Closer Look at the Nutrient Quality of Grain, Grain-Based Products, and the Role of Organic Agriculture Erin Smith, Charles Benbrook, Donald R. Davis, The Organic Center -- Jul 2012