Figure 2.

Effect of increasing soil temperature on the CO₂ efflux from (a) intact soil cores, (b) cores packed with sieved mineral soil, and (c) the roots which were excised during the disaggregation of the intact soil cores. Soil cores (0–10 cm soil depth) were sampled from subplots which had been exposed to soil warming throughout 9 seasons (full triangles, means ± SE, n = 3) and from subplots which had experienced the corresponding natural temperature conditions (open circles, means ± SE, n = 3).