Ponderosa Pine Forest Restoration Treatment Longevity: Implications of Regeneration on Fire Hazard
Abstract
:1. Introduction
2. Materials and Methods
2.1. Study Region
2.2. Stand Inventory Design
2.3. Model and Simulation Parameterization
2.4. Fire Hazard Modeling
2.5. Analysis
3. Results
4. Discussion
5. Conclusions
Acknowledgments
Author Contributions
Conflicts of Interest
References
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Site | Thinning Status | Site Index § (m) | Tree ha−1 | Basal Area (m2 ha−1) | QMD † (cm) | CBH † (m) | Species Proportion * |
---|---|---|---|---|---|---|---|
Boulder County Open Space | Pre | 11 | 417 | 18.9 | 23.9 | 3.0 | PIPO †† (99%) |
Post | 296 | 14.3 | 24.9 | 3.4 | PIPO (99%) | ||
Roosevelt National Forest | Pre | 17 | 410 | 14.0 | 20.8 | 2.4 | PIPO (95%) PSME †† (4%) |
Post | 148 | 9.0 | 27.9 | 4.6 | PIPO (97%) PSME (3%) | ||
Pike National Forest | Pre | 23 | 711 | 29.0 | 22.9 | 3.0 | PIPO (86%) PSME (13%) |
Post | 245 | 15.5 | 26.9 | 5.2 | PIPO (86%) PSME (11%) | ||
Kaibab National Forest | Pre | 29 | 410 | 25.5 | 28.2 | 4.0 | PIPO (100%) |
Post | 190 | 19.8 | 36.3 | 8.2 | PIPO (100%) |
Site | Thinning Status | FVS-FFE Derived Parameters | CFIS Fire Hazard Level | |||
---|---|---|---|---|---|---|
CBD † (kg m−3) | FSG † (m) | SFC † (kg m−2) | Torching (km h−1) | Crowning (km h−1) | ||
Boulder County Open Space | Pre | 0.084 | 1.5 | 0.744 | 7.5 | 13.2 |
Post | 0.060 | 2.9 | 0.741 | 12.0 | 20.7 | |
Roosevelt National Forest | Pre | 0.051 | 1.5 | 0.236 | 7.5 | 14.1 |
Post | 0.034 | 3.6 | 0.230 | 11.9 | 43.1 | |
Pike National Forest | Pre | 0.044 | 0.9 | 0.815 | 6.2 | 25.3 |
Post | 0.025 | 3.7 | 0.805 | 10.7 | 67.3 | |
Kaibab National Forest | Pre | 0.045 | 2.4 | 0.676 | 9.2 | 30.1 |
Post | 0.028 | 6.7 | 0.671 | 18.0 | 57.7 |
Dependent Variable Torching | |||||
β | SE * | p-Value | LB * | UB * | |
β0—Intercept | 22.558 | 5.764 | <0.001 | 11.262 | 33.855 |
β1—Site Index | 0.053 | 0.068 | 0.432 | −0.080 | 0.186 |
β2—Seedlings | −0.009 | 0.002 | <0.001 | −0.013 | −0.005 |
β3—Distribution | |||||
Single Narrow | 0 | - | - | - | - |
Single Long | 11.563 | 4.286 | <0.010 | 3.162 | 19.963 |
Dual Narrow | 8.125 | 4.291 | <0.100 | −0.284 | 16.534 |
Constant | 6.562 | 4.294 | 0.432 | −1.853 | 14.977 |
Dependent Variable Crowning | |||||
β | SE * | p-Value | LB * | UB * | |
β0—Intercept | 46.764 | 17.627 | <0.010 | 12.215 | 81.313 |
β1—Site Index | 0.748 | 0.214 | <0.001 | 0.329 | 1.167 |
β2—Seedlings | −0.034 | 0.006 | <0.001 | −0.046 | −0.022 |
β3—Distribution | |||||
Single Narrow | 0 | - | - | - | - |
Single Long | 9.874 | 13.244 | 0.456 | −16.084 | 35.832 |
Dual Narrow | 17.086 | 13.326 | 0.200 | −9.031 | 43.204 |
Constant | 13.572 | 13.282 | 0.307 | −12.460 | 39.603 |
Dependent Variable Torching | |||||||
CRNMULT | 1.0 | 0.5 | 0.0 | ||||
β (p-Value) | LB–UB * | β (p-Value) | LB–UB * | β (p-Value) | LB–UB * | ||
β0—Intercept | 22.558 (<0.001) | 11.262–33.855 | 24.420 (<0.001) | 14.368–34.472 | 21.497 (<0.001) | 14.298–28.695 | |
β1—Site Index | 0.053 (0.432) | −0.080–0.186 | −0.011 (0.856) | −0.129–0.107 | −0.083 (<0.100) | −0.167–0.002 | |
β2—Seedlings | −0.009 (<0.001) | −0.013–(−0.005) | −0.008 (<0.001) | −0.011–(−0.004) | −0.003 (<0.010) | −0.005–(−0.001) | |
β3—Distribution | |||||||
Single Narrow | 0 | 0 | 0 | ||||
Single Long | 11.563 (<0.010) | 3.162 –19.963 | 8.438 (<0.050) | 0.969–15.906 | 7.813 (<0.010) | 2.472–13.153 | |
Dual Narrow | 8.125 (<0.100) | −0.284–16.534 | 2.500 (0.513) | −4.992–9.992 | 1.250 (0.647) | −4.100–6.600 | |
Constant | 6.562 (0.432) | −1.853–14.977 | 6.875 (<0.100) | −0.597–14.347 | 2.500 (0.359) | −2.846–7.846 | |
Dependent Variable Crowning | |||||||
CRNMULT | 1.0 | 0.5 | 0.0 | ||||
β (p-Value) | LB–UB * | β (p-Value) | LB–UB * | β (p-Value) | LB–UB * | ||
β0—Intercept | 46.764 (<0.010) | 12.215–81.313 | 43.835 (<0.010) | 14.014 –77.655 | 49.074 (<0.001) | 26.228–71.919 | |
β1—Site Index | 0.748 (<0.001) | 0.329–1.167 | 0.702 (<0.001) | 0.317–1.086 | 0.309 (<0.050) | 0.040–0.578 | |
β2—Seedlings | −0.034 (<0.001) | −0.046–(−0.022) | −0.032 (<0.001) | −0.042–(−0.021) | −0.019 (<0.001) | −0.027–(−0.012) | |
β3—Distribution | |||||||
Single Narrow | 0 | 0 | 0 | ||||
Single Long | 9.874 (0.456) | −16.084–35.832 | 10.784 (0.377) | −13.140–34.708 | 3.004 (0.729) | −13.983–19.992 | |
Dual Narrow | 17.086 (0.200) | −9.031–43.204 | 11.479 (0.347) | −12.457–35.414 | 7.211 (0.406) | −9.780–24.202 | |
Constant | 13.572 (0.307) | −12.460–39.603 | 11.985 (0.327) | −11.959–35.929 | 4.629 (0.593) | −12.358–21.617 |
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Tinkham, W.T.; Hoffman, C.M.; Ex, S.A.; Battaglia, M.A.; Saralecos, J.D. Ponderosa Pine Forest Restoration Treatment Longevity: Implications of Regeneration on Fire Hazard. Forests 2016, 7, 137. https://doi.org/10.3390/f7070137
Tinkham WT, Hoffman CM, Ex SA, Battaglia MA, Saralecos JD. Ponderosa Pine Forest Restoration Treatment Longevity: Implications of Regeneration on Fire Hazard. Forests. 2016; 7(7):137. https://doi.org/10.3390/f7070137
Chicago/Turabian StyleTinkham, Wade T., Chad M. Hoffman, Seth A. Ex, Michael A. Battaglia, and Jarred D. Saralecos. 2016. "Ponderosa Pine Forest Restoration Treatment Longevity: Implications of Regeneration on Fire Hazard" Forests 7, no. 7: 137. https://doi.org/10.3390/f7070137