Open Access Research Paper Views (500) Download (14) Effect of nitrogen fertilizer different levels on economic indices, energy balance indices and greenhouse gases of current rice cultivars in Guilan Ebrahim Azarpour, Ghasem Farajpour J. Bio. Env. Sci.3( 10), 1-11, October 2013. Key: CultivarEconomicEnergy balanceGreenhouse gasesNitrogenRice Details