Table 4.
Root biomass between grazing and non-grazing practices in northern China grasslands.
| Study and effect | Duration† | Statistics | ||||||
|---|---|---|---|---|---|---|---|---|
| Difference in means | Standard error | Variance | Lower limit | Upper limit | Z-value | p-value | ||
| (# of yrs) | ---------------------------------- (g m−2) --------------------------------- | |||||||
| Yang et al. 2016b | 5 | −468.0 | 100.6 | 10124.9 | −665.2 | −270.8 | −4.7 | 0.000 |
| Xu et al. 2014 | 11 | −86.0 | 35.0 | 1225.3 | −154.6 | −17.3 | −2.5 | 0.014 |
| Xu et al. 2014 | 11 | 0.4 | 2.7 | 7.3 | −4.9 | 5.7 | 0.1 | 0.885 |
| Zhang et al. 2018c | 11 | 0.6 | 0.1 | 0.0 | 0.4 | 0.8 | 5.9 | 0.000 |
| Zhu et al. 2018 | 11 | 8.7 | 1.6 | 2.5 | 5.6 | 11.8 | 5.5 | 0.000 |
| Wang et al. 2017b | 9 | 20.0 | 3.9 | 14.9 | 12.4 | 27.6 | 5.2 | 0.000 |
| Xu et al. 2014 | 11 | 20.3 | 49.8 | 2480.8 | −77.3 | 118.0 | 0.4 | 0.683 |
| Xu et al. 2014 | 18 | 25.8 | 4.0 | 15.8 | 18.0 | 33.6 | 6.5 | 0.000 |
| Xu et al. 2014 | 11 | 31.4 | 6.1 | 36.7 | 19.5 | 43.2 | 5.2 | 0.000 |
| Xu et al. 2014 | 1 | 48.7 | 8.4 | 70.1 | 32.3 | 65.1 | 5.8 | 0.000 |
| Zhang et al. 2017 | 4 | 65.0 | 18.8 | 352.1 | 28.2 | 101.8 | 3.5 | 0.001 |
| Zhang et al. 2017 | 25 | 93.0 | 26.8 | 720.8 | 40.4 | 145.6 | 3.5 | 0.001 |
| Zhang et al. 2018b | 1 | 114.1 | 41.4 | 1713.4 | 33.0 | 195.2 | 2.8 | 0.006 |
| Rong et al. 2017 | 2 | 120.0 | 36.0 | 1298.1 | 49.4 | 190.6 | 3.3 | 0.001 |
| Wang et al. 2017b | 25 | 133.0 | 25.6 | 655.5 | 82.8 | 183.2 | 5.2 | 0.000 |
| Zhang et al. 2017 | 4 | 140.0 | 40.4 | 1633.3 | 60.8 | 219.2 | 3.5 | 0.001 |
| Zhang et al. 2004 | 25 | 140.8 | 12.6 | 157.6 | 116.2 | 165.5 | 11.2 | 0.000 |
| Yan et al. 2016a | 3 | 144.0 | 85.1 | 7246.4 | −22.8 | 310.8 | 1.7 | 0.091 |
| Yan et al. 2016a | 4 | 187.0 | 69.2 | 4783.0 | 51.4 | 322.6 | 2.7 | 0.007 |
| Zhang et al. 2004 | 2 | 214.8 | 15.6 | 241.8 | 184.3 | 245.3 | 13.8 | 0.000 |
| Zhang et al. 2004 | 5 | 241.2 | 18.7 | 349.9 | 204.5 | 277.9 | 12.9 | 0.000 |
| Wang et al. 2017b | 25 | 250.0 | 45.8 | 2093.3 | 160.3 | 339.7 | 5.5 | 0.000 |
| Zhang et al. 2017 | 18 | 258.0 | 74.5 | 5547.0 | 112.0 | 404.0 | 3.5 | 0.001 |
| Zhang et al. 2004 | 1 | 265.8 | 21.3 | 452.2 | 224.2 | 307.5 | 12.5 | 0.000 |
| Yan et al. 2016a | 3 | 278.0 | 85.9 | 7379.0 | 109.6 | 446.4 | 3.2 | 0.001 |
| Yan et al. 2016a | 5 | 284.0 | 75.5 | 5702.2 | 136.0 | 432.0 | 3.8 | 0.000 |
| Zhang et al. 2004 | 18 | 295.8 | 21.9 | 480.5 | 252.8 | 338.7 | 13.5 | 0.000 |
| Yan et al. 2016a | 18 | 327.0 | 74.5 | 5549.0 | 181.0 | 473.0 | 4.4 | 0.000 |
| Wang et al. 2017b | 11 | 407.0 | 74.3 | 5527.5 | 261.3 | 552.7 | 5.5 | 0.000 |
| Mean (n = 222) | 97.6 | 7.3 | 53.6 | 83.2 | 111.9 | 13.3 | 0.000 | |
†The duration (number of years) of the treatments (Master tab24) or the number of samplings for the specific study.