Cattle manure is a major source of anthropogenic nitrous oxide (N₂O), an important and long-lived greenhouse gas. In most intensive production systems, manure can be managed to reduce N₂O production and utilize CH4. However, 48% of cattle production in the US is associated with semi-arid and low-humid rangelands. Livestock production in semi-arid regions depends on few water sources. Much of the manure ends up near these water reservoirs, resulting in very high concentrations of NO₃^-, NH₄⁺, and readily available C; conditions that can potentially result in very high N₂O fluxes.  In order to improve our understanding of N₂O production by semi-arid landscapes, we determined the effects of increased temperature and increases or decreases in precipitation on four ecosystems along an elevation gradient near Flagstaff, Arizona. N₂O production increased with elevation and precipitation, but significant interactions with ecosystems were found. We also determined the effect of soil moisture on N₂O production at high manure deposition rates near water sources. We estimate that 1% of the semi-arid landscape associated with the manure accumulation near water sources produces 30% of the total N₂O. This estimate is very sensitive to changes in amounts and intensity of precipitation.