Table 2 Effect of agricultural management practices on soil C stock, C credit and financial returns under different experimental durations. The database of the meta-analyses can be found as Supplementary Tables S1–S4 online
Duration (year) | Relative change in C stock (kg C ha−1 year−1) | CO2-equivalent (kg CO2 ha−1 year−1) | C credit (I) (AUD ha−1 year−1) | N input to stabilise C storagec(kg N ha−1 year−1) | N cost to stabilise C storaged (II) (AUD ha−1 year−1) | Financial returns (I–II) (AUD ha−1 year−1) | |||
|---|---|---|---|---|---|---|---|---|---|
Mean | 95% CI | Voluntarya | CFIb | Voluntary | CFI | ||||
Conservation tillage | |||||||||
0–10 | 150 | 97 to 210 | 551.5 | 1.8 | 12.7 | 15.0 | 19.6 | −17.8 | −6.9 |
11–20 | 100 | 58 to 142 | 364.8 | 1.2 | 8.4 | 10.0 | 13.0 | −11.9 | −4.6 |
21–30 | 40 | 1 to 86 | 147.8 | 0.5 | 3.4 | 4.0 | 5.3 | −4.8 | −1.9 |
31–40 | 6 | −6 to 20 | 0 | 0 | 0 | NA | NA | NA | NA |
Residue retention | |||||||||
0–10 | 147 | 40 to 276 | 537.5 | 1.7 | 12.4 | 14.7 | 19.1 | −17.5 | −6.8 |
11–20 | 71 | 46 to 98 | 260.3 | 0.8 | 6.0 | 7.1 | 9.3 | −8.4 | −3.3 |
21–30 | 21 | −15 to 65 | 0 | 0 | 0 | NA | NA | NA | NA |
31–40 | 4 | −4 to 13 | 0 | 0 | 0 | NA | NA | NA | NA |
Use of pasture | |||||||||
0–10 | 132 | 42 to 259 | 482.2 | 1.5 | 11.1 | 13.2 | 17.2 | −15.7 | −6.1 |
11–20 | NA | NA | NA | NA | NA | NA | NA | NA | NA |
21–30 | 75 | 57 to 95 | 275.4 | 0.9 | 6.3 | 7.5 | 9.8 | −8.9 | −3.5 |
31–40 | 60 | 40 to 79 | 218.9 | 0.7 | 5.0 | 6.0 | 7.8 | −7.1 | −2.8 |
Fertiliser N application | |||||||||
0–10 | 67 | 20 to 112 | 247.1 | 0.8 | 5.7 | 6.7 | 8.8 | −8.0 | −3.1 |
11–20 | 40 | 18 to 60 | 145.2 | 0.5 | 3.3 | 4.0 | 5.2 | −4.8 | −1.8 |
21–30 | NA | NA | NA | NA | NA | NA | NA | NA | NA |
31–40 | 14 | 7 to 22 | 51.7 | 0.2 | 1.2 | 1.4 | 1.8 | −1.7 | −0.7 |
