Field and laboratory soil respiration measurements: relations with soil properties

Soil CO2 effluxes show high spatial and temporal variability, mainly due to variations in chemical, physical and biological soil properties. Vegetation also plays an important role in the soil respiration process. Information on spatial heterogeneity in soil respiration can be useful to accurately quantify the carbon balance of ecosystems and also can be useful for other studies (e.g., for advection experiments in Eddy Covariance sites). This study was part of the Carboeurope IP ADVEX experiment. We investigated the relationships between field soil respiration measurements, soil chemical and physical properties, microbial biomass and soil basal respiration measured in laboratory. During the advection ADVEX 2006 experiment, field measurements of soil respiration were taken in a spruce forest in Germany (Wetzstein) at 80 plots within the target area of the experiment. After the experiment, soil cores, in correspondence of each soil respiration measurement point, were collected. Each horizon was separately analyzed for C, N, microbial biomass, and fine root content. Measurements of basal respiration for each soil horizon were made in the laboratory. The results showed a good correlation between field measurements and soil properties. In addition, soil respiration data obtained in the laboratory were well correlated both with field measurements and soil properties. The results may help reducing uncertainty due to soil respiration variability and may be helpful to scale soil respiration by means of modeling.