35% of total GHG emissions in 2010 were from sources other than burning fossil fuels
From Figure TS.1, 65% of total GHG emissions are "CO2, Fossil Fuel and Industrial Practices." So, 100% - 65% = 35%.
Intergovernmental Panel on Climate Change, IPCC Working Group III Contribution to AR5, Ottmar Edenhofer et al., “Technical Summary,” in Climate Change 2014: Mitigation of Climate Change, 2014, 42, Figure TS.1, accessed January 20, 2015, http://www.ipcc.ch/pdf/assessment-report/ar5/wg3/ipcc_wg3_ar5_technical-...