Soil scientist Ray Archuleta shows a remarkable contrast in the responses of tilled and no-tilled soil to water. Note that the biological glue he speaks of during the second half, substances such as glomalin, are one of the important large compounds that contain soil carbon. The takeaway from this demonstration is also that soil organic carbon has huge leverage on the effectiveness of the water cycle. See also http://managingwholes.com/eco-water-cycle.htm
John Todd, of Living Machines fame and the New Alchemy Institute, has an interesting essay on http://www.thesolutionsjournal.com/node/634 about the need for our urban and industrial society to understand the foundational role of soil, and the carbon cycle.