Figure 1.
Mean values of temperature and precipitation of the study area (2004∼2011).
Vertical bars indicate standard errors of means (n = 8).
Figure 2.
Daily courses of soil temperature at different measuring depths at the adjacent natural conditions (data of Jun-21 and 22).
T0, T5, T10, T20, T30 and T40 represent temperature measured at 0, 5, 10, 20, 30 and 40-delay of daily highest temperature from T0, and values are 60, 240, 420, 740 and 960 sec minutes for a, b, c, d and e, respectively.
Figure 3.
Dependence of the time-delay of daily highest temperature from T0 (mean ± SE), values of Q10, R2 and RSS on the depth of soil temperature measuring point.
Sub-Fig (A), (B), (C) and (D) represent time-delay from T0, values of Q10, R2 and RSS, respectively. Q10: the temperature sensitivity of RS; RSS: residual sum of squares of the exponential function.
Figure 4.
Mean values of temperature and soil moisture under different water addition regimes without FOM treatments.
Sub-Fig (A) and (B) represent temperature and soil moisture, respectively. Vertical bars indicate standard errors of means (n = 3). FOM: fresh organic matter; F0: no FOM input; P0, P1, P2: no added water, 50% and 100% increase in water addition, respectively.
Figure 5.
Daily means of soil respiration (mean ± SE) under different treatments.
Sub-Fig (A), (B) and (C) represent soil respiration rate under P0, P1 and P2 treatments, respectively. Vertical bars indicate standard errors of means (n = 3). F1 and F2: 5% and 10% increase in soil organic carbon. Other abbreviations are same as Figure 4.
Figure 6.
Mean values (mean ± SE) of soil respiration under different treatments and at the natural condition site in total study period.
Sub-Fig (A) and (B) represent soil respiration under different treatments and natural site, respectively. Vertical bars indicate standard errors of means (n = 3). Bars with different lowercase letters are significantly different from each other at p<0.05. Abbreviations are same as Figure 5.
Figure 7.
Fresh organic matter and water addition induced change percentages in soil respiration rate (mean ± SE).
Sub-Fig (A) and (B) represent fresh organic matter and water addition induced change percentages, respectively. Vertical bars indicate standard errors of means (n = 3). * represent significant different compared with controls at P<0.01. Other abbreviations are same as Figure 4.
Table 1.
Results (F-Values) of ANOVA with fresh organic matter (FOM) and water addition, and their interactions on soil respiration.
Figure 8.
Relationship between soil respiration (mean ± SE) and soil temperature under different FOM and water addition treatments.
An exponential was used to describe the relationship. Vertical bars indicate standard errors of means (n = 3). Inserts represent the residuals from the equation. Other abbreviations are same as Figure 4.
Table 2.
Fitted relationships of soil respiration (µmol m–2 s–1) with soil moisture (at 10 cm soil depth) (W, %) in all treatments.
Table 3.
Fitted relationships of soil respiration (µmol m–2 s–1) with soil moisture (at 10 soil depth) (W, %) and soil temperature (T, at soil surface, °C).
Table 4.
Soil C input–emission balanced with different FOM and water addition treatments during study period. Data are in contrast to the controls (F0P0).