Table 3.
Sediment sample (cm) | C-bkgrd OM Remineral | Bkgrd OM reactivity (k) | Percentage of tracer carbon respired | Enhanced OM decomposition | ||||||||||||
---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
Percentage of tracer remineralization | Percentage of bkgrd remineralization | |||||||||||||||
Ox | Anox | Ox | Anox | Ox | Anox | Ox | Anox | Ox | Anox | |||||||
1× | 10× | 1× | 10× | 1× | 10× | 1× | 10× | 1× | 10× | 1× | 10× | |||||
Subtidal 0–2 | 0.26 | 0.21 | 4.4 | 3.7 | 19 | 26 | 16 | 23 | 393 | 108 | 531 | 27 | 8 | 29 | 10 | 7 |
Subtidal 18–20 | 0.08 | 0.13 | 0.9 | 1.6 | 11 | 15 | 20 | 25 | 11 | 51 | 300 | 62 | 0.4 | 25 | 12 | 31 |
Intertidal 0–2 | 0.44 | – | 16.3 | – | ||||||||||||
Day 7 | 19.7 | – | 120 | – | 22 | – | ||||||||||
Day 14 | 29.9 | – | 91 | – | 14 | – | ||||||||||
Day 21 | 33.2 | – | 119 | – | 15 | – |
Also given is the percent of the tracer OM respired in the different treatments that received a single low (1×) and tenfold (10×) load of tracer amendment
In the last column, enhanced OM decomposition (priming of indigenous OM) is presented as both percentage of tracer carbon respired and as percentage of C-background OM remineralization rates, again with 1× versus 10× addition under oxic and anoxic conditions
All values are average of n = 3