Abstract:
The soil respiration rate (
Rs) and its influential factors of two green landscapes (GL and YZ) were measured using a portable automated CO
2 exchange station (ACE) during the whole growing season in Tianjin.The relationships be-tween soil respiration and its influential factors of soil temperature, soil moisture and soil physicochemical properties have been analyzed.Results show that:(1) There was basically no difference in the seasonal variation of
Rs between the two different types of green landscapes, both of them showed an obvious single-peak variation and the peak appeared at the same time.Simultaneously, the variation of
Rs was different in different months.In dry season, the
Rs was low with few fluctuations, which ranged from (0.20±0.03) to (1.09±0.16) μmol·m
-2·s
-1 for GL, and from (-0.06±0.01) to (0.26±0.05) μmol·m
-2·s
-1 for YZ.Conversely, a relatively higher
Rs with more fluctuations was noted in the wet sea-son, it seemed to be varied from (-0.05±0.01) to (3.62±0.26) μmol·m
-2·s
-1 for GL, and from (0.38±0.07) to (3.17±0.27) μmol·m
-2·s
-1 for YZ.In summary, the mean value of
Rs in GL was significantly higher than that in YZ; (2) The environmental factors that influence
Rs are very complicated in the two green landscapes.The two relatively im-portant factors are soil temperature at 10 cm depth (
T10) and soil moisture at 5 cm depth (
M5).In addition, the regression analysis show that the effective degree of
T10 and
M5 for
Rs were 45.4%-64.8% and 21.1%-52.2%, respectively; (3) There was a certain correlation between soil physicochemical properties and
Rs, in which the correlation coefficient between soil organic matter and
Rs was highest in all the two green landscapes.