http://blogs.ei.columbia.edu/2010/03/24/nitrogen-and-wastewater-kartik-chandran-interview-part-2/ Tapping experts in climate, geology, oceanography, ecology, sustainable development, global health, energy, food and water, State of the Planet captures stories of how the Earth works and how we can sustainably make our lives better. Fri, 17 May 2013 14:54:37 +0000 hourly 1 http://wordpress.org/?v=3.5.1