climate report for the bonito forest restoration...
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Climate Report
For
The Bonito Forest Restoration Project
Author: Adapted from previous reports by Adam Mendonca
Date: September 19, 2009
/s/ Adam Mendonca
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Background
The role of climate as a driver in ecosystem function is well established (e.g., Stenseth et al.
2002). Long-term climate trends have the potential to exacerbate GHG emissions issues and
represent a large challenge for all land managers. Throughout the Intermountain West, scientists
project increases in temperatures and changes in precipitation patterns that would likely result in
reduced snowpack, earlier spring snowmelt and runoff, lower stream flows in summer, altered
groundwater recharge, and increased soil moisture stress. These changes may lead to more
frequent and longer drought periods, more insect outbreaks, declining water supplies in an era of
increasing demand and more intense wildfire seasons
A changing climate may affect forests in several ways, ranging from direct effects on
temperature and precipitation, as well as indirect effects of increased atmospheric CO2
concentrations on tree growth and water use, further alteration of fire regimes and changes in
range and severity of pest outbreaks. Climate change has the potential to transform entire forest
systems and shift forest distribution and composition. Some modeling estimates show that
boreal forests may decline as much as 50% (Noss, 2001). As a result, the importance of
adaptive forest management approaches that enhance ecosystem resilience to disturbance will
increase (Malmsheimer et al, 2008). Management must develop strategies that anticipate
increased insect and disease epidemics and increases in wildfire frequency and severity due to
climate change.
Trees are a major depository of significant amounts of the earth’s recyclable carbon, thereby
helping offset the large amounts of carbon dioxide (CO2) emitted by factories, motor vehicles,
and other sources. When trees burn down or die, much of that carbon is returned to the
atmosphere. Consequently, it can take decades for forest re-growth to sequester the amount of
carbon emitted in a single, stand replacing fire. The reduction of wildland fires through active
management has significant impacts on reducing greenhouse gas (GHG) emissions
(Malmsheimer et al. 2008).
Wildfires of a nature that reduce entire stands of timber not only inject great quantities of carbon
into the atmosphere, but change the landscape through soil erosion and the subsequent alteration
of watersheds. It has been estimated that active management of forest landscapes has the
potential to decrease the acreage burned by high intensity wildfires by 50 to 60 percent (Finney
2000). Prescribed fire managers follow stringent air quality and burn plan requirements. In
addition to detailed weather and fuel modeling, prescribed burn emissions must comply with
federal and state air quality requirements.
Resistance is the capacity of an ecosystem to avoid or withstand disturbance, such as anticipated
increased insect and disease epidemics and wildfires. Management actions should aim at
increasing resistance and thus forestall damage and protecting valued resources, such as water,
endangered species, wildland-urban interface areas, and special forest stands. Resiliency is
defined as the ability of an ecosystem to recover quickly from a disturbance by promoting
ecological processes and diversity in vegetative composition and structure (Noss, 2001).
Treatments that promote both resistance and resiliency include thinning of overstocked stands,
prescribed burning, removal of invasive species, and restoration of native species. This general
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principle of maintaining ecosystems through resistance and resiliency can also be applied to
landscapes affected by climate change.
Malmsheimer et al. (2008) also point out that active forest and wildland fire management
strategies can dramatically reduce CO2 emissions while conserving wildlife habitat, preserving
recreational, scenic, and wood product values, and reducing the threat of wildfires to
communities and critical infrastructure. Furthermore, the success of a sequestration strategy
depends on ensuring full stocking, maintaining ecosystem health, minimizing soil disturbance,
and reducing increased losses due to tree mortality, wildfires, insect, and disease. For example,
treatments such as thinnings are known to reduce competition for soil moisture and nutrients,
thus reducing competition-based stress and increasing resistance to attacks from insects and
disease and resilience to drought and weather anomalies (Malmsheimer et al, 2008).
Existing Condition
The Bonito Forest Restoration Analysis Area covers approximately 28,488 acres of the Bonito
Wildland Urban Interface area. The Bonito Analysis Area consists of parcels of land in both the
White Mountain Wilderness and non-wilderness lands that are part of the Bonito watershed. The
Bonito Analysis Area encompasses U.S. Forest Service land bordering private holdings of
individuals and the city of Alamogordo in the Bonito Lake Area. The Bonito Forest Restoration
treatment area, however, is limited to 12,465 acres of non-wilderness public land less 582 acres
of no treatment/nest core within Mexican Spotted Owl (MSO) Protected Activity Centers (PACs)
and the 274 acres of the Teflor Research Natural Area. These 11,160 acres of treatable forest sits
astride portions of the watershed that feeds the Rio Bonito drainage that forms Bonito Lake.
Bonito Lake is a municipal water supply for Alamogordo, Holloman Air Force Base and smaller
communities. The city of Alamogordo owns 2,243 acres on the southern border of the treatment
area while private lands border the treatment area on both the north and east sides. The State of
New Mexico also owns land that borders the treatment area. Not only is the treatment area a
major source of clean water but it is also home to a federally listed threatened species, the MSO.
The Ruidoso Red Squirrel and the Sacramento Salamander are endemic subspecies that reside in
the mixed conifers on the treatment area. Large mammals such as elk, deer and woodland
raptors such as the Northern Goshawk are also found in the area. The scenic beauty and wildlife
of the area make it a desirable spot for birders, hunters and recreationist.
Historically, fire maintained a diverse and patchy mosaic of mixed conifer, ponderosa pine,
pinyon-juniper, shrub, and grasslands in a frequent mixed-severity fire regime on the treatment
area. Scar data suggests a return interval at 26 years with a range of 12-55 years between fires.
From 1916 to 2006 there were 226 lightning and human caused fires with an average of two fires
per year. However, since the era of modern wildfire suppression, most fires have been
contained and extinguished quickly. The effect of this suppression has been to alter the historic
cycle of low intensity ground fires which has resulted in an explosion of trees and a reduction in
the historic park-like structure of these forests. Surveys have shown acreages with as many as
3,887 trees per acre with 80% below 9” dbh on ponderosa pine stands. Monocultural stands of
great numbers of trees represent an unnatural state that is susceptible to high intensity wildlfires
that could remove old growth forests, alter watersheds and contribute to GHG (Kuhar, 2009).
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Alternative 1 – No Action
Alternative one, no action, continues the degrading of the treatment area through the current
management practice of fire suppression and non-treatment which is creating an unnatural
environment of overgrown forests. Although this continuation of current management policy
might be beneficial to shade tolerant plants, it is not the condition of the forest based on
historical data from pre-Columbus eras to the age of European settlement in the late 19th
and
early 20th
centuries (Kuhar, 2009). Alternative one also creates the potential for a large wildfire;
specifically a high-intensity wildfire of catastrophic proportion which would significantly alter
the landscape for generations. Under this alternative there is an increase in the potential for an
increased amount of carbon to be released during a high intensity wildfire. Althought the
increase in carbon would be negligible when effects analysis are expanded to a larger scale.
Direct, Indirect, and Cumulative Effects
This alternative would not reduce or increase GHG emissions by mechanical treatments or
prescribed fire. The effect of no action would be an increased undesirable fire behavior such as
stand replacing fires.
Without management action, much of the Bonito Forest Restoration treatment area would remain
at increased risk of stand replacing fire and stand development would continue its departure from
historic conditions with respect to species composition, stand densities, surface and canopy fuels,
fire hazard and GHG emissions. Canopy fuels and ladder fuels would continue to increase with
the increased establishment of shade tolerant species such as white fir and semi-shade tolerant
Douglas-fir seedlings and saplings.
The effect of no action also means continued accumulation of surface fuels and further increases
in stand densities, and should a large wildfire occur, increased smoke emissions (as compared to
prescribed fire) for the following reasons:
more acres would likely burn in a more compressed time frame,
fire weather conditions would be hotter and drier, thus increasing fire behavior such as
high intensity fires,
traditionally, fuel moistures are lower during wildfires on the Smokey Bear Ranger
District (late spring, early summer) versus fall or early spring prescribed fire, thus
resulting in more fuel consumption, and
high intensity fire behavior would consume live canopy fuels on a large scale where
prescribed fire would be largely limited to surface fuels.
The area considered for cumulative effects is the treatment area boundary. The time period
considered for cumulative effects is 50 years. Past actions and natural disturbances have all
contributed to the current condition and the departure from the natural disturbance regimes.
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These actions have resulted in increases in understory vegetation and surface fuels, changes in
species composition, and vegetative continuity.
Under the no action alternative, the cumulative effects of past management actions and the
continuation of fire suppression without management action would result in the area trending
toward greater surface and canopy fuels increasing fire hazard and increased GHG emissions.
Alternative 2 – Thinning with Road Reconstruction
Prescribed fire with no mechanical treatment has been analyzed for acres located within the
project area where tree densities are not high enough to warrant mechanical thinning but would
still provide an ecological benefit.
Thinning treatments would involve cutting trees while retaining current species composition,
mechanical and hand piling of slash, followed by activity fuels treatment (pile burning) and
broadcast burning following commercial treatments and would result in some GHG emissions.
Machine and hand piles would be burned in the winter when snow is on the ground or during
monsoon season to minimize fire spread and reduce scorching on the residual stand. This also
distributes the GHG emissions over a larger time period instead of potentially at one time from a
stand replacing wildfire. Fire from pile burning would be allowed to creep within unit
boundaries.
To improve the resistance of the project area to drought and fire risk stands would be thinned to
densities and species composition such they would be resilient under a variety of potential future
climates. Lower densities are more likely to survive future drought stress, fire, and insect and
disease problems.
Ponderosa pine and mixed conifer stands would be thinned so that they are likely to remain
healthy should the sites become warmer and dryer due to changing climate. Thinning within
these stands would retain the existing species composition, rather than modifying the species
composition of the existing stand. This would retain diversity and provide species capable of
thriving in either wetter or dryer conditions.
Alternative two, preferred alternative, includes the thinning and prescribed burning of 11,610
acres of non-wilderness lands that border private and incorporated lands near Bonito Lake. The
effect of alternative 2 would be the reduction of crown fire potential by removing small diameter
trees. The majority of the thinning would be in mixed conifer and ponderosa pine with 8,512
acres of this vegetation type thinned up to 9 inches dbh and species selection towards mid-seral
tree species. Free thinning in this mixed conifer and ponderosa zone would leave at least 20 trees
per acre less than 9” dbh and striving to maintain an uneven-aged stand. Approximately 535
acres of strictly mixed conifer would be free thinned up to 24” dbh thus favoring large tree
retention over smaller trees and striving for an uneven-age nature. This thinning would favor
healthy and vigorous trees while selected low vigor, diseased or insect stressed trees for removal.
In addition, 377 acres of ponderosa pine would be free thinned across all diameter ranges thus
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favoring large trees and striving to create an uneven-aged stand. Another 1,940 acres of pińon-
juniper within the project area would be thinned by group selection by removing all trees less
than 14” in diameter at the root collar. Species preference for the mixed conifer and ponderosa
would be in the following order: southwestern white pine, ponderosa pine, Douglas-fir, piñon
pine, juniper and white fir. Piñon/juniper forests species preference during thinning would be in
the order of ponderosa pine, piñon pine and juniper. Vigorous and healthy individuals could be
removed but the species selection in piñon/juniper and ponderosa would favor mid-seral species.
Thinning would be conducted through various methods including manual or mechanical felling
or in combination or with other extractive means that are reasonable on grades approaching 40
percent. Biomass removal could use ground-based, cable, or skyline log removal. Trees may be
left on the ground after felling due to difficulties in terrain or to meet criteria established for logs
as outlined for certain species of wildlife such as Sacramento salamanders, Mexican spotted owls
or Northern goshawks. A fire cycle regimen of one to five years through prescribed burning
would be done by accepted practices of ground based or aerial ignition. Firelines may be
constructed during prescribed burns to control fire movement and these firelines will be dug to
mineral soil. Alternative firelines such as vegetative, blackline, or wetline might also be used
and in accordance to standard procedures in difficult terrain. To facilitate thinning activities
within the treatment area, alternative 2 would involve the recontruction of 4.0 miles of level 1
roads. These roads would allow for the removal of cut woody material as well as provide fire
access during implementation of the project. These roads will be gated and only open to thinning
crews, forest personnel and necessary machinery during the time needed to complete the project.
These roads will be closed after the project is completed. The removal of material would aid in
reducing the total amount of carbon released during burning operations. This reduction, when
analized on a larger scale would become negligible.
Direct, Indirect, and Cumulative Effects
The direct effects of the Proposed Action on climate change (GHG emissions and carbon
cycling) might include short-term GHG emissions and alteration to the carbon cycle from
hazardous fuels reduction, and longer-term GHG emissions and effects to the carbon cycle by
thinning overstocked stands to increase forest resilience and decrease the potential for large scale
wildfire. Restoring the health, resilience, and productivity of the vegetation in the Bonito Forest
Restoration treatment area may also improve the capability of the stands or landscape to
withstand climate change stresses in the form of drought, catastrophic fire and insect and disease
outbreaks.
The removal of biomass, and thus carbon, through thinning, harvesting and prescribed fire,
would be offset with increased biomass in the form of understory vegetation. Species diversity
would also be increased along with carbon sequestration in the understory, and long term
reduction in smoke or other GHG emitted by potential stand replacing fires would offset this.
Removal of biomass would be a short term impact and in the long term an increase or flush of
understory would occur depending on precipitation amounts and timing. Smoke can be
measured from prescribed burns, and prescribed burns could lead to additional air quality
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benefits. Previous research has indicated that such burns could reduce emissions of pollutants
such as fine particulate matter and carbon monoxide.
In research examining the effectiveness of pre-wildfire fuels treatments, Omi et al. (2006) found
that “only treatments that reduced both canopy and surface fuels in combination showed
significant correlation to weather conditions and the effectiveness of these treatments actually
increased with weather severity.”
Prescribed fires can increase the ability to recover quickly after a disturbance (forest resiliency)
from insect and disease and is a climate change strategy that would be applied to the Bonito
Forest Restoration treatment area. Following treatments planned in the proposed action, grasses
and forbs are expected to increase, and wildlife habitat is improved and increased after
prescribed fire treatments. Over time, the return to a patchy, mosaic forest with a diverse
understory could have a positive impact/effect on carbon sequestration. The increased
productivity in the understory creates a carbon sink due to increased biomass in the understory
production of grasses, forbs, and shrubs.
The proposed action includes the option to implement prescribed fire across the entire project
area. This would directly release CO2 during the burning operation in the project area.
However, Wiedinmyer and Hurteau (2010) indicate that restoring (or maintaining) historic
conditions would result in a lower risk of uncharacteristically severe wildfire for these treated
acres. This reduced risk has a two-fold effect on GHG emissions or the carbon cycle:
There is a direct beneficial effect on climate change of decreased GHG emissions from
these acres because the risk of acres being burned by uncharacteristically severe wildfires
would be reduced, and prescribed burns, often used by forest managers to reduce
underbrush and protect bigger trees, release substantially less carbon dioxide emissions
than wildfires of the same size.
There is an indirect beneficial effect by treating these acres because live stands of trees
would retain higher capacity to sequester carbon dioxide compared to stands killed by
uncharacteristically severe wildfires, especially if not immediately reforested. Wildfires
often destroy large trees that store significant amounts of carbon. Prescribed fires are
designed to burn underbrush and small trees, which store less carbon. By clearing out the
underbrush, these controlled burns reduce the chances of subsequent high-severity
wildfires, thereby protecting large trees and keeping more carbon locked up in the forest.
Alternative 3: Thinning with No Road Reconstruction
Alternative three utilizes the same treatment prescriptions across the project area as alternative
two; however, alternative three will not re-open any level 1 roads. Consequently, this alternative
may alter rehabilitation by:
Increasing the length of time for the completion of the project .
Leaving a debris field or untreated timber will increase fire hazard.
Increasing the mortality to residual timber stands during prescribed
burning.
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The treatments that will be utilized if alternative two or three is selected as the preferred
alternative are described in the table below (Kuhar, Fire and Fuels Report Revised, 2009)
Table 1: Vegetation Types: Acreage and Proposed Treatments
Treatment
Description
Acres/
% of
project
Logging
System Silvicultural Treatments
Mixed Conifer 535
5%
Ground Based
Commercial
Thin(>9”dbh), free thin across diameter
ranges to 24”dbh, 80ft2
to 100 ft2 BA per
acre, prescribed fire
Ponderosa Pine 377
3%
Ground Based
Commercial
Thin(>9”dbh), free thin favoring large
trees, 40ft2
to 80ft2 BA per acre, enhance
uneven-aged nature; prescribed fire
Mixed
Conifer/Ponderosa
Pine
8512
73%
Ground Based Thin-from-below(<9”), free thin to
prescribed basal area; leave at least 20
trees per acre less than 9” dbh, 80ft2
to
100 ft2 BA per acre, prescribed fire
Pińon/Juniper 1940
17%
Ground Based Thin (>9” dbh), group selection removing
all trees less than 14” (DRC) in a mosaic
pattern; prescribed fire
Grasslands 246
2%
Prescribed
Burn Only
Prescribed fire
Total 11,610
According to the Forest Silviculturist the following prescribed burning mortality rates for each
vegetation type will occur under this project:
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Table 2. Prescribed Burning Vegetation Mortality Rates
Vegetation Type Mortality Rate %
Pinon/Juniper The overall mortality of the seedlings may be as high as
40%, but the mortality of juniper greater than 4” drc should
be 5-10%, and pinon 5” drc and greater should not exceed
15%.
Ponderosa Pine The overall mortality should not be greater than 25%, but
the mortality of the ponderosa pine 5” dbh and greater
should not exceed 10%.
Mixed Conifer The overall mortality should not be greater than 25%, but
the mortality of the mixed conifer 5” dbh and greater
should not exceed 10%.
Transportation
Ground-based removal on some of the areas within the Bonito treatment area would require the
reconstruction of approximately 4.0 miles of temporary (Level 1) roads. Level one maintained roads
are roads that have been closed to the public and have basic custodial care. Approximately 3.0 miles
of temporary road would be reconstructed in the Loma Grande area with an additional 1.0 miles of
road in the Philadelphia Canyon area. These temporary roads would be utilized for woody material
removal and administrative use only. Gates will be installed and locked outside of treatment periods.
These roads will be closed upon project completion to reduce long term impacts. All skid trails and
landings would be closed to all motorized use and rehabilitated upon completion of treatment
activities. Rehabilitation needs would be identified by the contract officer representative upon
completion of a treatment contract and might include disking, seeding with native species, or pulling
residual slash across disturbed sites.
After hazardous fuel reduction objectives have been met, surface fuel loads would start to
increase again over time and be maintained with prescribed fire that would mimic a historical
fire regime within the historic range of variability.
Past actions and natural disturbances include large fire scars, fire suppression, timber harvest and
grazing and have contributed to current conditions. Cumulatively, this project, in combination
with the fuel treatments already planned within the project area would have a positive effect on
protection of life and property through the reduction of severe wildfire potential across the
landscape. Goals, outcomes and impacts of the Bonito Forest Restoration Project are shown in
the Appendix, Table 3.
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References (Literature Cited)
Blate, G.M., Joyce, L.A., Littell, J.S., McNulty, S.G., Millar, C.I., Moser, S.C., Neilson, R.P.,
O’Halloran K., and. Peterson D.L. Adapting to climate change in United States national
forests. Unasylva 231/232, Vol. 60, 2009
Finney, M.A. 2000. Design of regular landscape fuel treatment patterns for modifying fire
growth and behavior. Forest Science Journal 47(2):219 –228.
Kaufmann, Merrill R.; Huckaby, Laurie S.; Regan, Claudia M.; and Popp, John. Forest
Reference conditions for ecosystem management in the Sacramento Mountains, New Mexico.
1998. General Technical Report RMRS-GTR-19. Fort Collins, Colorado: USDA Forest
Service Rocky Mountain Research Station, 87p.
Kuhar, Kim, 2009. “Fire and fuels Report: Bonito forest Restoration Project” Smokey Bear
Ranger District.
Malmsheimer, R. W., P. Heffernan, S. Brink, D. Crandall, F. Deneke, C. Galik, E. Gee, J. A.
Helms, N. McClure, M. Mortimer, S. Ruddell, M. Smith, and J. Stewart. Forest Management
Solutions for Mitigating Climate Change in the United States. Journal of Forestry. April/May
2008 115-128.
Noss, Reed F. Beyond Kyoto: forest Management in a Time of Rapid Climate Change,
Conservation Biology, June, 2001 v. 15, No. 3.
Stenseth, N.C., A. Mysterud, G. Ottersen, J.W. Hurrell, K.-S. Chan and M. Lima. 2002.
Ecological effects of climate fluctuations. Science 297:1292–1296.
Wiedinmyer, C. and M.D. Hurteau. Prescribing Fire as a Means of Reducing Forest Carbon
Emissions in the Western United States. Environmental Science and Technology. Vol 44, No
6, 2010. 1926-1932.
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Appendix
Table 3: Goals, outcomes, impacts and options: Bonito Forest Restoration Project
Goal Desired or intended
outcome
Possible climate
change
impacts
Adaptation options
Restore, sustain, and
enhance
- Hazardous fuels
- Suitable timber land
- Forage production
- Watershed condition
- Historic Structure
Restoration
Maintain forest
health,
productivity, diversity
and resistance to
severe
disturbances
Longer, warmer
growing seasons
Shifts in seasonality
of
hydrological
processes
Intense droughts
Reduce fuel loads in
forests
Enhance the early
detection and
response strategy
associated with
non-native invasive
species
Provide and sustain
benefits
to the local
communities
Maintain multiple
socioeconomic
benefits to meet
society’s needs over
the long
term, including a
reliable supply
of forest products,
energy
resource needs and
market based
conservation
Climate change
interacting with
current
stress factors such as
insect pests
and disease, wildfire,
legacy of past
management and air
pollution
Shifts in forest species
composition
Increased erosion
events impairing
watershed condition
Increase efforts to
reduce current stress
factors
Incorporate long-term
climate change
into wildland fire
planning
Develop silvicultural
treatments to reduce
drought stress
Review genetic
guidelines for
reforestation
Sustain and enhance
outdoor
recreation opportunities
Maintain high-quality
outdoor
recreation
opportunities in
national forests
available to the
public
Increased air and
stream temperatures
Reduced snowpack
Altered in-stream
flows
Evaluate recreational
impact on
ecosystems under a
changing climate
Expand recreational
opportunities across
all four seasons
Redesign roads and
trails to withstand
increased rainfall
intensity
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Supplement to Climate Report
For
The Bonito Forest Restoration Project
Author: Sabrina Flores, Lincoln National Forest Planner
Date: June 21, 2011
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Alternatives Two and Three, Action Alternatives
Direct, Indirect, and Cumulative Effects Supplement:
Forests are a critical carbon pool in the global balance of GHGs. Carbon emissions and savings
from the proposed project are highly uncertain. Also, because greenhouse gases mix readily into
the global pool of greenhouse gases, it is not currently possible to ascertain the indirect effects of
emissions from single or multiple sources (projects). In addition, because the large majority of
Forest Service projects are extremely small in the global atmospheric CO2 context, it is not
presently possible to conduct quantitative analysis of actual climate change effects based on
individual or multiple projects.
It is known that risks of increased wildfire, outbreaks of insects and disease, and invasive
species, represent ongoing, broad-scale management challenges. Even the most moderate
climatic change scenarios predict increasing insect and disease epidemics and wildfire impacts.
These issues are nothing new, however, climate change has the potential to increase or augment
the impacts of these ecosystem risks. A beneficial direct effect of the Bonito project is to make
this ecosystem more resilient to the potential impacts of these increased ecosystem risks.
Preventing or suppressing fire in order to maximize carbon sequestration would destabilize
ecosystems that require fire and also increase carbon losses caused by wildfires in the long term.