The temperature responses of soil respiration in deserts: a seven desert synthesis

The temperature response of soil respiration in deserts is not well quantified. We evaluated the response of respiration to temperatures spanning 67A degrees C from seven deserts across North America and Greenland. Deserts have similar respiration rates in dry soil at 20A degrees C, and as expected, respiration rates are greater under wet conditions, rivaling rates observed for more mesic systems. However, deserts differ in their respiration rates under wet soil at 20A degrees C and in the strength of the effect of current and antecedent soil moisture on the sensitivity and magnitude of respiration. Respiration increases with temperature below 30A degrees C but declines for temperatures exceeding 35A degrees C. Hot deserts have lower temperature sensitivity than cold deserts, and insensitive or negative temperature sensitivities were predicted under certain moisture conditions that differed among deserts. These results have implications for large-scale modeling efforts because we highlight the unique behavior of desert soil respiration relative to other systems. These behaviors include variable temperature responses and the importance of antecedent moisture conditions for soil respiration.