Table 1.
Descriptive statistics for Pinus edulis and Juniperus monosperma trees across all plots and experimental treatments in year 2007 (baseline) and 2012 (with mortality effects)
| Biomass Parameter | Irrigation year-2007 (n = 3) | Ambient year-2007 (n = 3) | Drought year-2007 (n = 3) | Irrigation year-2012 (n = 3) | Ambient year-2012 (n = 3) | Drought year-2012 (n = 3) |
|---|---|---|---|---|---|---|
| Total basal area (m2 ha−1) | 24.3 (2.1) | 20.0 (1.7) | 17.6 (0.2) | 23.8 (2.0) | 19.8 (1.7) | 12.2 (2.6) |
| Piñon basal area (m2 ha−1) | 5.2 (0.8) | 2.4 (0.3) | 1.9 (0.4) | 4.7 (0.7) | 2.2 (0.4) | 0.6 (0.2) |
| Juniper basal area (m2 ha−1) | 19.1 (1.8) | 17.7 (1.4) | 15.7 (0.6) | 19.1 (1.8) | 17.6 (1.4) | 11.6 (2.6) |
| Total sapwood area (m2 ha−1) | 4.83 (0.46) | 3.21 (0.25) | 2.82 (0.28) | 4.65 (0.39) | 3.13 (0.32) | 1.68 (0.23) |
| Piñon sapwood area (m2 ha−1) | 2.30 (0.36) | 1.04 (0.11) | 0.87 (0.18) | 2.12 (0.27) | 0.97 (0.16) | 0.28 (0.10) |
| Juniper sapwood area (m2 ha−1) | 2.53 (0.21) | 2.17 (0.14) | 1.95 (0.11) | 2.53 (0.21) | 2.16 (0.15) | 1.40 (0.16) |
| Total stem density (>5 cm, ha−1) | 567 (46) | 350 (22) | 354 (85) | n/a | n/a | n/a |
| Piñon stem density (>5 cm, ha−1) | 173 (20) | 77 (15) | 69 (13) | n/a | n/a | n/a |
| Juniper stem density (>5 cm, ha−1) | 394 (30) | 273 (35) | 285 (74) | n/a | n/a | n/a |
| Leaf area index (m2 m−2) | 1.09 (0.10) | 0.77 (0.06) | 0.68 (0.04) | n/a | n/a | n/a |
| Woody Canopy Coverage (%) | 47.5 (1.9) | 36.6 (3.0) | 32.3 (4.1) | n/a | n/a | n/a |
Basal area estimates are based on diameter measured at 30-cm stem height. Sapwood area and LAI were predicted using allometric equations developed on-site in 2007. For individuals with multiple stems at 30-cm height, a single equivalent diameter was calculated. Woody canopy coverage was estimated from aerial photographs of the study site and included all woody shrubs and trees. Annual mortality estimates for each species (by plot) were developed from periodic tree/canopy dieback surveys performed on target trees in each plot and whole-plot stem inventories and mortality status checks performed in 2007, 2011, and 2014. Error bars represent (±1 SE) of the mean.