Environmental Engineering Reference
In-Depth Information
600
bare land
T.chinensis;
S.glauca
P.australis
500
400
300
200
100
0
Apr
May
Jun
Jly
Agu
Sep
Oct
Nov Dec
Month
Figure 1. Annual CO2 flux for salt marsh and different communities.
3.2. Variation of CH 4 Flux from Different Vegetation
CH 4 flux ranged from -0.075 to 0.185 mg/(m 2 ·h) and the annual average flux is 0.003
mg/(m 2 ·h) (Figure 2), indicating that the salt marsh is a weak CH 4 source (Figure 2). During
spring and summer, sampling site acted as a weak CH 4 sink, while a source in autumn and
winter. The season flux followed the order: spring (-0.004 mg/(m 2 ·h)) <summer (-0.004
mg/(m 2 ·h)) <winter (0.004 mg/(m 2 ·h)) <autumn (0.015 mg/(m 2 ·h)).
0.4
bare land
T.chinensis;
S.glauca
P.australis
0.3
0.2
0.1
0.0
-0.1
-0.2
Apr May Jun
Jly
Agu
Sep
Oct
Nov Dec
Month
Figure 2. Annual CH 4 flux for salt marsh and different communities.
The emission of CH 4 among the four marshes were not significantly different ( P>0.05 ).
Except the bare land, the others were all acted as a week CH 4 sink, and the value followed the
order: T. chinensis (-0.012 mg/(m 2 ·h)) < S. glauca (-0.006 mg/(m 2 ·h)) < P. australis (-0.006
mg/(m 2 ·h)) < bare land (0.037 mg/(m 2 ·h)).
3.3. Variation of Environmental Factors
Similar variation patterns of air temperature and soil temperature were observed between
the four sampling sites and the maximum and minimum value appeared in July and December
Search WWH ::




Custom Search