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Letters XXXX XXXX / Vol. XX No. X BioScience 1
Primary Forests Are Undervalued in
the Climate Emergency
Scientists are increasingly alarmed
by the accelerating climate and
biodiversity crises, as, for example,
Ripple and colleagues (2020), recently
published in BioScience and signed
by three of us (DAD, BM, BR) during
the initiating letter. However, decision-
makers rarely recognize the inextri-
cable link between biodiversity and
climate change. We cannot solve one
without the other. Earths biosphere
contains enormous carbon stocks that
have the potential to fundamentally
alter the trajectory of climate change.
Biodiversity is crucial for stabilizing
these carbon stocks and keeping them
out of the atmosphere.
The climate change mitigation ben-
efit of forests in general is to store
large amounts of carbon in a stable,
self-regenerating and long-term res-
ervoir. Therefore, even if we eliminate
fossil fuels, continued deforestation
and forest degradation will generate
severe climate disruptions: the carbon
stocks in the living biomass of primary
(unlogged) tropical forests alone is
approximately 114 petagrams of car-
bon, equivalent to the estimated global
carbon budget for a 66% probability
of meeting the 1.5 degrees Celsius
global warming target. While most
climate policy is aimed at fossil fuels,
it is critically important to also protect
forest carbon. The mitigation potential
of forests is recognized by Ripple and
colleagues (2020) and others (Griscom
et al. 2017) but the significance of
protecting forests, especially primary
forests, is not sufficiently promoted.
Primary forests represent roughly
one-third of remaining forests glob-
ally (Mackey et al. 2014). They
contain irreplaceable biodiversity
intertwined with critical ecosystem
services that help regulate the global
climate and maintain stable carbon
pools. Carbon-dense primary forests
are found in every major forest biome
and they typically support higher lev-
els of biodiversity than logged forests,
especially imperiled and endemic spe-
cies. These forests store approximately
30%–50% more carbon than logged
ones, with the largest trees accounting
for most of the above ground living
stores. Some of the densest terrestrial
carbon pools are in primary boreal
forests in the peatlands of Canada
and Russia, Pacific coastal temper-
ate rainforests, wet temperate eucalypt
forests in southeast Australia, and west
coast temperate rainforests in Chile
and New Zealand.
Despite claims that tree plant-
ing is essential to stabilize the global
climate, the mitigation potential of
planting trees is trivial if we do not
prioritize primary forest protection
followed by proforestation of logged
forests (Moomaw et al. 2019). Ceasing
deforestation and degradation of pri-
mary forests has an immediate mitiga-
tion benefit, whereas carbon stored
in newly planted trees will take many
decades to make a significant contribu-
tion to reducing atmospheric carbon
dioxide. Proforestation that buffers
and reconnects even small areas of
primary forests would improve ecosys-
tem integrity, stability, and long-term
carbon storage.
We applaud scientists who sound the
alarm about the climate and biodiver-
sity crises. We now need to prioritize
the most effective nature-based climate
solutions, led by primary forests protec-
tions and proforestation, and supported
by much needed forest-climate policies
and greatly expanded financial invest-
ments (Mackey et al. 2014).
The research reported here was sup-
ported in part by a private charitable
trust that wishes to remain anonymous
to avoid unsolicited funding requests.
The trust has had no influence on the
design, analysis, interpretation, and
documentation of this research.
Dominick A. DellaSala
( is affiliated
with the Geos Institute, in Ashland,
Oregon. Cyril F. Kormos is affiliated
with Wild Heritage, in Berkeley,
California. Heather Keith and Brendan
Mackey are affiliated with the Griffith
Climate Change Response Program, at
Griffith University, in Mount Gravatt,
Queensland, Australia. Virginia Young
is affiliated with the International
Climate and Forest Programme, part of
the Australian Rainforest Conservation
Society, in Bardon, Queensland,
Australia. Brendan Rogers is affiliated
with the Woods Hole Research Center,
in Falmouth, Massachusetts. Russell A.
Mittermeier is affiliated with Global
Wildlife Conservation, in Austin, Texas.
Griscom BW, et al. 2017. Natural climate solu-
tions. Proceedings of the National Academy
of Sciences 114: 11645–11650.
Mackey B, et al. 2014. Policy options for the
world’s primary forests in multilateral envi-
ronmental agreements. Conservation Letters
8: 139–147.
Moomaw WR, Masino SA, Faison EK. 2019. Intact
forests in the United States: Proforestation mit-
igates climate change and serves the greatest
good. Frontiers in Forests and Global Change.
Ripple WJ, Wolf C, Newsome TM, Barnard P,
Moomaw WR. 2020. World scientists’ warning
of a climate emergency. BioScience 70: 8–12.
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... The water flow regulation and water quality benefits of maintaining forest cover may accrue to communities at a regional scale, further down the catchmentfor example, to those exploiting fisheries downstream over the medium term (Reed et al., 2017). Also, many benefits are global and long-run, such as the role played by primary forests as sanctuaries for threatened biodiversity (Thompson et al., 2012;Watson et al., 2018), in globally-significant levels of carbon sequestration and storage (Dellasala et al., 2020;Mackey et al., 2020) and the avoided costs of potential pandemics from avoided deforestation and degradation (Dobson et al., 2020). In contrast, the costs (including effort, direct financial and opportunity costs) of maintaining forest ecosystems services largely falls on local owners, managers or custodians of the forest at the local or landscape level, who are often Indigenous, customary or Traditional custodians. ...
... related ecosystem structure and function (Zimmerman and Kormos, 2012). Furthermore, they do not generally recognise the different and unique ES inherent in primary forests when compared to secondary, degraded and plantation forests (Dellasala et al., 2020;Mackey et al., 2020Mackey et al., , 2015Watson et al., 2018). ...
Forests generate a range of ecosystem services at global, local and regional scales but deforestation and forest degradation is increasing in many regions of the world, with primary forests under particular threat. At the same time, the communities that own and live in and around these forests are seeking incomes for development in an increasingly globalised world. The failure to comprehensively recognise, demonstrate and capture the value of the ecosystem services of forests, means that forests are seen primarily as a source of timber, or forest land as simply an opportunity for agriculture and mining. Forest communities, that have often harnessed the forest for centuries, are often faced with a false choice between conservation and development. A number of mechanisms exist to create incomes from the forest through more sustainable activities that recognise and seek to capture forest ecosystem service benefits beyond timber. This paper examines the literature on four key mechanisms – (i) forest certification, (ii) non-timber forest products, ecotourism and eco-labelling, (iii) payments for ecosystems services and (iv) forest carbon mitigation schemes (reducing emissions from deforestation and degradation) to determine how they recognise, demonstrate and capture ecosystem services and to identify their strengths, weaknesses opportunities and threats. It is argued that while the mechanisms recognise multiple ecosystem services, they struggle to demonstrate their value, and thus ineffectively capture them in forest management and income-generation for forest stewards. The paper uses the analysis to propose the essential requirements of a ‘Basket of Benefits Approach’ that provides guidance for more comprehensive valuation of forest ecosystem services, inclusive of ecosystem integrity, that enables just benefit sharing. This Approach considers all the benefits and the beneficiaries to be within the ‘basket’, and therefore that agreement on values and equitable sharing of the benefits, through participatory planning and governance, is essential
... Primary and old-growth forests generally have received increased attention internationally as natural climate solutions (DellaSala et al., 2020;IUCN, 2020;Law et al., 2021), including from policy makers 1 (e.g., March 22, 2022) and conservation non-governmental organizations (NGOs) in the United States 2 ; 3 (accessed May 15, 2022). Article 5.1 of the Paris Climate Agreement calls on governments to protect and enhance "carbon sinks and reservoirs, " while Article 21 of the UNFCCC COP26 Glasgow Climate Pact emphasizes "the importance of protecting, conserving and restoring nature and ecosystems, including forests. . . to achieve the longterm global goal of the Convention by acting as sinks and reservoirs of greenhouse gases and protecting biodiversity. . ...
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... Forests are vital ecosystems at a global, regional and local scale, and are especially important for responding to climate change and protecting biodiversity [1][2][3]. In particular, primary forests-those not subject to management for commodity production and other industrial scale commercial uses and whose structure and function are dominated by natural processes [4]-provide a greater array of high quality services, compared to secondary growth forests or plantations [5][6][7]. Consequently, protecting areas of primary forest needs to be a priority for forest management. The Democratic Republic of Congo (DRC) forest cover has over 100 million ha of primary forest, with 60% classified as within 'intact forest landscapes', and has the largest contiguous area of tropical forest outside of the Amazon [8]. ...
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Primary forests are essential ecosystems that can play a key role in mitigating climate change. REDD+ is designed to help countries and communities secure benefits for avoiding deforestation but has faced significant implementation challenges. There are substantial potential benefits for REDD+ in the Democratic Republic of Congo (DRC), where shifting agriculture is the major cause of deforestation. However, implementation requires significant capacity building in a number of sectors and at a number of levels. This paper explores how well the capacity building activities within the DRC REDD+ strategy are aligned with the capacity needs identified by provincial government stakeholders and local communities in the Équateur province of the DRC, identified through workshops and surveys. The research suggests that while many technical capacity needs identified by stakeholders could be potentially addressed by the REDD+ strategy, there are number of systemic capacity needs that are unlikely to be addressed. Failure to address these needs risks undermining any implementation of REDD+. The results suggest that education and training in governance and management, as well as fundamental education in sustainability, are key capacity needs that REDD+ may need to incorporate. The results also provide further evidence that REDD+ projects need to be long-term and take into account the local context and needs in order to be effective.
... The Forest Restoration pathway distribution prioritises buffering and reconnection of primary forests and other carbon dense primary ecosystems, which increases resilience, stability and adaptive capacity [59,60]. Some of the highest sequestration values (80-100 t C ha −1 ) overlap with biodiversity and carbon 'hotspots' in the Amazon Basin and Southeast Asia [61]; carbon densities of 70-90 t C ha −1 are also notable across China and northern Europe where a significant area of this pathway is represented (figure 1). ...
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Limiting global warming to a 1.5°C temperature rise requires drastic emissions reductions and removal of carbon-dioxide from the atmosphere. Most modelled pathways for 1.5°C assume substantial removals in the form of biomass energy with carbon capture and storage, which brings with it increasing risks to biodiversity and food security via extensive land-use change. Recently, multiple efforts to describe and quantify potential removals via ecosystem-based approaches have gained traction in the climate policy discourse. However, these options have yet to be evaluated in a systematic and scientifically robust way. We provide spatially explicit estimates of ecosystem restoration potential quantified with a Dynamic Global Vegetation Model. Simulations covering forest restoration, reforestation, reduced harvest, agroforestry and silvopasture were combined and found to sequester an additional 93 Gt C by 2100, reducing mean global temperature increase by ~0.12°C (5-95% range 0.06-0.21°C) relative to a baseline mitigation pathway. Ultimately, pathways to achieving the 1.5°C goal garner broader public support when they include land management options that can bring about multiple benefits, including ecosystem restoration, biodiversity protection, and resilient agricultural practices.
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A number of technical solutions have been proposed for tackling global climate change. However, global climate change is not the only serious global environmental challenge we face demanding an urgent response, even though atmospheric CO2 ppm have risen from 354 in 1990 to 416 in 2020. The rise of multiple global environmental challenges makes the search for solutions more difficult, because all technological solutions give rise to some unwanted environmental effects. Further, not only must these various problems be solved in the same short time frame, but they will need to be tackled in a time of rising international tensions, and steady global population increase. This review looks particularly at how all these environmental problems impact the future prospects for renewable energy (RE), given that RE growth must not exacerbate the other equally urgent problems, and must make a major difference in a decade or so. The key finding is that, while the world must shift to RE in the longer run, in the short term what is more important is to improve Earth’s ecological sustainability by the most effective means possible. It is shown that reducing both the global transport task and agricultural production (while still providing an adequate diet for all) can be far more effective than converting the energy used in these sectors to RE.
The Democratic Republic of Congo (DRC) has over 100 million Ha of forest and has significant potential to benefit from these forests, including through REDD+ if they are managed effectively. Effective governance of forest landscapes is essential for environmental management and equitable harnessing of ecosystem service benefits for communities. Poor governance, political instability, and capacity limitations in the DRC are widely highlighted. However, there have been few, if any, attempts to evaluate forest governance in the DRC, especially at the community level. This paper reports a community-level evaluation of forest governance in the DRC, using a survey method. The results suggest that REDD+ projects have the ability to improve forest governance as perceived by the community. The research shows that building the right capacity, consulting and accessing the needs of the community and building long-term projects and partnerships a key success factors. These findings and the novel approach to supporting communities to evaluate their governance are applicable to similar community-level forest governance contexts.
The role of nature restoration in mitigating the impacts of climate change is receiving increasing attention, yet the mitigation potential is often assessed in terms of carbon removal rather than the ability to meet temperature goals, such as those outlined in the Paris Agreement. Here, we estimate the global removal potential from nature restoration constrained by a “responsible development” framework and the contribution this would make to a 1.5°C temperature limit. Our constrained restoration options result in a median of 103 GtC (5%–95% range of −91 to 196 GtC) in cumulative removals between 2020 and 2100. When combined with deep-decarbonization scenarios, our restoration scenario briefly exceeds 1.5°C before declining to between 1.25°C and 1.5°C by 2100 (median, 50% probability). We conclude that additional carbon sequestration via nature restoration is unlikely to be done quickly enough to notably reduce the global peak temperatures expected in the next few decades. Land restoration is an important option for tackling climate change but cannot compensate for delays in reducing fossil fuel emissions.
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Context Information on the maturity of forests is important for conservation planning. However, available information for the USA is inadequate to support national conservation assessment and planning. Objectives The main objective was to spatially model at a high resolution the relative level of maturity and stand development for forests across conterminous USA. A secondary objective was to explore which younger forests could be attributed to the impacts of severe natural disturbances. Methods We modelled the relative level of maturity for forests at a 30 m pixel resolution using spatial data for forest cover, height and biomass, stratified by forest types and ecoregions. National plot data were used to validate modelled results. The impact on Young forest from severe wildfire, insects and disease, and tornados was examined for the years 2000-2019. Results Of a total forest area of 248.9M ha, Young forest covered 52.9 M ha (22%); Intermediate 100.3 M ha (42%); and Mature 86.0 M ha (36%). Results suggest that the modelled data are tracking observed forest structure and stand development. 1.4 M ha (2.67%) of modelled Young forest was impacted by severe natural disturbances, with 51.5 (97.33%) M ha of Young forest unimpacted. The distribution of the disturbance factors varied geographically. The unimpacted Young plus Mature forest are where primary forests are most likely found. Conclusions The forest maturity data can assist forest decision makers in meeting environmental commitments regarding mitigating forest sector emissions, biodiversity conservation and water quality, including through prioritizing land for meeting protected area and ecosystem restoration targets.
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Abstract The Interior Wetbelt (IWB) of British Columbia includes the globally rare Inland Temperate Rainforest (ITR) that if managed for its substantial carbon (C) stocks can contribute to Canada's Nationally Determined Commitment under the Paris Climate Agreement. We provide spatially explicit estimates of above‐ and belowground live and dead biomass and soil C stocks derived from three sources: (1) government online Vegetation Resources Inventory (VRI); (2) the GlobBiomass spatial dataset; and (3) field plots (n = 27) within old‐growth forests of the ITR. For live aboveground C, we summarize C stocks by elevation classes and decadal forest age. The upper bound on total C densities (above‐ and belowground live and dead biomass and soil C) based on VRI was a maximum of 806 megagrams (Mg) C ha−1. The mean total biomass C density measured in field plots was 583 Mg C ha−1 with a maximum of 1275 Mg C ha−1, which is on par with some of the world's most C‐dense temperate forests. About half the C is in live biomass pools with the rest in dead biomass and soil organic C pools. The mean C density from the VRI over all elevations was 182 Mg C ha−1, with soil organic C ~40% and live tree stems ~27%. Vegetation Resources Inventory estimates were 75% lower than field‐based measurements with the greatest mismatch in areas with the highest C density. Approximately 22% of the IWB has been logged, the majority since 1970s, resulting in live above ground C declining by at least 18%, although this is likely an underestimate. Logging was heavily concentrated in low (2000 m; 1.2%). The region contains underappreciated C stocks that can help Canada meet its climate and conservation targets, but only if there are major forestry reforms that protect C‐dense old‐growth forests, allow degraded forests time to recover the logging‐related C debt, and improve monitoring of C stocks and stock changes.
Protecting forests is an increasingly essential and urgent priority to address the climate and biodiversity crises. These forests are home to communities, often Indigenous communities, who are facing multiple pressures including industrial extraction (logging and mining), illegal activities, as well as population growth and development, all of which drive land use change, forest loss and degradation. Addressing these multiple pressures requires integrated landscape approaches. Landscape planning has an important role to play in forest protection and conservation, including in areas of tropical primary forest in developing countries. However, resource and capacity limitations mean that planning activities in these contexts are often informal and nascent, rather than highly formalised in planning documents, and evaluation is limited. Robust tools to guide evaluation in emergent planning contexts can help improve planning processes and outcomes, and guide planners (community-based and otherwise) to choose and apply the right planning tools for the context. This paper develops an evaluation framework of principles, criteria and indicators for assessing informal and emerging forest landscape planning processes. The framework is designed particularly for stakeholders involved in forest landscapes planning processes with few resources and where formal technical capacity is limited. The framework will help guide and improve landscape planning for forest protection and sustainability.
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Climate change and loss of biodiversity are widely recognized as the foremost environmental challenges of our time. Forests annually sequester large quantities of atmospheric carbon dioxide (CO 2), and store carbon above and below ground for long periods of time. Intact forests-largely free from human intervention except primarily for trails and hazard removals-are the most carbon-dense and biodiverse terrestrial ecosystems, with additional benefits to society and the economy. Internationally, focus has been on preventing loss of tropical forests, yet U.S. temperate and boreal forests remove sufficient atmospheric CO 2 to reduce national annual net emissions by 11%. U.S. forests have the potential for much more rapid atmospheric CO 2 removal rates and biological carbon sequestration by intact and/or older forests. The recent 1.5 Degree Warming Report by the Intergovernmental Panel on Climate Change identifies reforestation and afforestation as important strategies to increase negative emissions, but they face significant challenges: afforestation requires an enormous amount of additional land, and neither strategy can remove sufficient carbon by growing young trees during the critical next decade(s). In contrast, growing existing forests intact to their ecological potential-termed proforestation-is a more effective, immediate, and low-cost approach that could be mobilized across suitable forests of all types. Proforestation serves the greatest public good by maximizing co-benefits such as nature-based biological carbon sequestration and unparalleled ecosystem services such as biodiversity enhancement, water and air quality, flood and erosion control, public health benefits, low impact recreation, and scenic beauty.
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Significance Most nations recently agreed to hold global average temperature rise to well below 2 °C. We examine how much climate mitigation nature can contribute to this goal with a comprehensive analysis of “natural climate solutions” (NCS): 20 conservation, restoration, and/or improved land management actions that increase carbon storage and/or avoid greenhouse gas emissions across global forests, wetlands, grasslands, and agricultural lands. We show that NCS can provide over one-third of the cost-effective climate mitigation needed between now and 2030 to stabilize warming to below 2 °C. Alongside aggressive fossil fuel emissions reductions, NCS offer a powerful set of options for nations to deliver on the Paris Climate Agreement while improving soil productivity, cleaning our air and water, and maintaining biodiversity.
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We identify policies that would provide a solid foundation in key international negotiations to ensure that primary forests persist into the 21st Century. A novel compilation of primary forest cover and other data revealed that protection of primary forests is a matter of global concern being equally distributed between developed and developing countries. Almost all (98%) of primary forest is found within 25 countries with around half in five developed ones (USA, Canada, Russia, Australia and NZ). Only ∼ 22% of primary forest is found in IUCN Protected Areas Categories I-VI, which is approximately 5% of pre-agriculture natural forest cover. Rates of deforestation and forest degradation are rapid and extensive, and the long-term integrity of primary forest cannot be assumed. We recommend four new actions that could be included in climate change, biodiversity, and sustainable development negotiations: (1) Recognize primary forests as a matter of global concern within international negotiations; (2) Incorporate primary forests into environmental accounting; (3) Prioritize the principle of avoided loss; and (4) Universally accept the important role of indigenous and community conserved areas. In the absence of specific policies for primary forest protection, their unique biodiversity values and ecosystem services will continue to erode.This article is protected by copyright. All rights reserved.
Policy options for the world's primary forests in multilateral environmental agreements
  • B Mackey