硝酸铵
Greenhouse gases are produced in the manufacture of many materials and products used by gardeners. For example, it takes a lot of energy to produce synthetic fertilizers, especially nitrogen fertilizers. Ammonium nitrate, for example, has an embodied energy of 67000 kilojoules/kilogramme, so climate-friendly gardeners will choose alternative ways of ensuring the soil in their gardens has optimal levels of nitrogen by alternative means such as nitrogen-fixing plants.