Risks to mitigation potential of forests
Much recent attention has focused on the potential of trees and forests to mitigate ongoing climate change by acting as sinks for carbon. Anderegg
et al.
...review the growing evidence that forests' climate mitigation potential is increasingly at risk from a range of adversities that limit forest growth and health. These include physical factors such as drought and fire and biotic factors, including the depredations of insect herbivores and fungal pathogens. Full assessment and quantification of these risks, which themselves are influenced by climate, is key to achieving science-based policy outcomes for effective land and forest management.
Science
, this issue p.
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BACKGROUND
Forests have considerable potential to help mitigate human-caused climate change and provide society with a broad range of cobenefits. Local, national, and international efforts have developed policies and economic incentives to protect and enhance forest carbon sinks—ranging from the Bonn Challenge to restore deforested areas to the development of forest carbon offset projects around the world. However, these policies do not always account for important ecological and climate-related risks and limits to forest stability (i.e., permanence). Widespread climate-induced forest die-off has been observed in forests globally and creates a dangerous carbon cycle feedback, both by releasing large amounts of carbon stored in forest ecosystems to the atmosphere and by reducing the size of the future forest carbon sink. Climate-driven risks may fundamentally compromise forest carbon stocks and sinks in the 21st century. Understanding and quantifying climate-driven risks to forest stability are crucial components needed to forecast the integrity of forest carbon sinks and the extent to which they can contribute toward the Paris Agreement goal to limit warming well below 2°C. Thus, rigorous scientific assessment of the risks and limitations to widespread deployment of forests as natural climate solutions is urgently needed.
ADVANCES
Many forest-based natural climate solutions do not yet rely on the best available scientific information and ecological tools to assess the risks to forest stability from climate-driven forest dieback caused by fire, drought, biotic agents, and other disturbances. Crucially, many of these permanence risks are projected to increase in the 21st century because of climate change, and thus estimates based on historical data will underestimate the true risks that forests face. Forest climate policy needs to fully account for the permanence risks because they could fundamentally undermine the effectiveness of forest-based climate solutions.
Here, we synthesize current scientific understanding of the climate-driven risks to forests and highlight key issues for maximizing the effectiveness of forests as natural climate solutions. We lay out a roadmap for quantifying current and forecasting future risks to forest stability using recent advances in vegetation physiology, disturbance ecology, mechanistic vegetation modeling, large-scale ecological observation networks, and remote sensing. Finally, we review current efforts to use forests as natural climate solutions and discuss how these programs and policies presently consider and could more fully embrace physiological, climatic, and permanence uncertainty about the future of forest carbon stores and the terrestrial carbon sink.
OUTLOOK
The scientific community agrees that forests can contribute to global efforts to mitigate human-caused climate change. The community also recognizes that using forests as natural climate solutions must not distract from rapid reductions in emissions from fossil fuel combustion. Furthermore, responsibly using forests as natural climate solutions requires rigorous quantification of risks to forest stability, forests’ carbon storage potential, cobenefits for species conservation and ecosystem services, and full climate feedbacks from albedo and other effects. Combining long-term satellite records with forest plot data can provide rigorous, spatially explicit estimates of climate change–driven stresses and disturbances that decrease productivity and increase mortality. Current vegetation models also hold substantial promise to quantify forest risks and inform forest management and policies, which currently rely predominantly on historical data.
A more-holistic understanding and quantification of risks to forest stability will help policy-makers effectively use forests as natural climate solutions. Scientific advances have increased our ability to characterize risks associated with a number of biotic and abiotic factors, including risks associated with fire, drought, and biotic agent outbreaks. While the models that are used to predict disturbance risks of these types represent the cutting edge in ecology and Earth system science to date, relatively little infrastructure and few tools have been developed to interface between scientists and foresters, land managers, and policy-makers to ensure that science-based risks and opportunities are fully accounted for in policy and management contexts. To enable effective policy and management decisions, these tools must be openly accessible, transparent, modular, applicable across scales, and usable by a wide range of stakeholders. Strengthening this science-policy link is a critical next step in moving forward with leveraging forests in climate change mitigation efforts.
Effective use of forests as natural climate solutions depends on accounting for climate-driven risks, such as fire and drought.
Leveraging cutting-edge scientific tools holds great promise for improving and guiding the use of forests as natural climate solutions, both in estimating the potential of carbon storage and in estimating the risks to forest carbon storage.
ILLUSTRATION: DAVID MEIKLE
Forests have considerable potential to help mitigate human-caused climate change and provide society with many cobenefits. However, climate-driven risks may fundamentally compromise forest carbon sinks in the 21st century. Here, we synthesize the current understanding of climate-driven risks to forest stability from fire, drought, biotic agents, and other disturbances. We review how efforts to use forests as natural climate solutions presently consider and could more fully embrace current scientific knowledge to account for these climate-driven risks. Recent advances in vegetation physiology, disturbance ecology, mechanistic vegetation modeling, large-scale ecological observation networks, and remote sensing are improving current estimates and forecasts of the risks to forest stability. A more holistic understanding and quantification of such risks will help policy-makers and other stakeholders effectively use forests as natural climate solutions.
Natural climate solutions are not enough Anderson, Christa M; DeFries, Ruth S; Litterman, Robert ...
Science (American Association for the Advancement of Science),
03/2019, Letnik:
363, Številka:
6430
Journal Article
Recenzirano
Decarbonizing the economy must remain a critical priority
Stabilizing Earth's climate and limiting temperature increase to well below 2°C per the Paris Agreement requires a dramatic uptick in the ...rate of progress on reducing greenhouse gas (GHG) emissions. Natural climate solutions (NCS) can be a substantial contributor, while also providing valuable cobenefits for people and ecosystems. Although analyses of NCS have some differences in the GHG fluxes they consider, all include emissions sources (such as deforestation, land-use change, and agricultural practices), emissions sinks (such as reforestation and restoring degraded lands), and non–carbon dioxide (CO
2
) agricultural emissions (such as methane from livestock). Some of us have contributed to among the most optimistic assessments of the potential of NCS (
1
), whereas others have been more pessimistic (
2
,
3
). But one thing on which we agree, and which technical literature generally acknowledges, is that the benefits of NCS do not decrease the imperative for mitigation from the energy and industrial sectors (
2
,
4
,
5
). Yet this point sometimes gets lost in public-facing conversations for example, are forests “our best weapon for fighting carbon emissions” or, more realistically, just one “piece of the puzzle”? (
6
). Strategies for incorporating NCS with energy and industrial mitigation in the climate portfolio should not be “either/or” but “yes, and.”
Climate change mitigation policies can have significant co-benefits for air quality, including benefits to disadvantaged communities experiencing substantial air pollution. However, the effects of ...these mitigation policies have rarely been evaluated with respect to their influence on disadvantaged communities. Here we assess the air pollution and environmental justice implications of California’s cap-and-trade mitigation program through analysis of (1) the sources of air pollution in disadvantaged communities, (2) emissions-reduction offset usage under the cap-and-trade program, and (3) the relationship between reductions in greenhouse gas emissions and reductions in co-pollutant emissions. Our analysis suggests that the cap-and-trade program has limited impacts, including limited disproportionate impacts, on air quality in disadvantaged communities. The sources of most air pollution in these communities have not been subject to the cap-and-trade program, and the use of emissions-reduction offsets is only marginally higher in disadvantaged communities than in other communities. Furthermore, reductions in greenhouse gas emissions imply smaller proportional reductions in co-pollutant emissions. While climate policies lead to important air quality co-benefits in some contexts, especially through reduced coal usage, targeted air quality policies and regulations may be more effective for reducing air pollution in disadvantaged communities in California and throughout the state.
Are forest offsets an effective way to address climate change, and do they provide other benefits? In some climate-change mitigation policies, industries and individuals can purchase offsets that ...compensate for their greenhouse-gas emissions by reducing emissions elsewhere. However, offsets may undermine mitigation efforts, by potentially giving carbon credits for emissions reductions that would have occurred even without the offset program in place. We evaluate California's forest offset program – the first-ever legally enforceable "compliance" offset program for existing forests – to determine whether offsets (1) provide additional emissions reductions that would not have occurred without the program (called "additionality") and (2) yield other benefits. We found that California's forest offset program, comprising a small portion of the state's mitigation portfolio, does not inhibit overall emissions reductions. Further, the program advances stringent "additionality" of emissions reductions through multiple mechanisms. Finally, mitigation through forest offsets can yield a suite of important co-benefits. Lessons from California's experience with forest offsets can help to inform other offset programs that are increasingly being developed around the world.
•Overlapping land use allocation decreases deforestation in the Peruvian Amazon.•Results are consistent across all types of land use allocations.•Findings inform land use policy for conflict ...avoidance, land tenure, and multiple use.
Overlapping land use allocations, in which one parcel of land is allocated two or more times for different uses, either intentionally or unintentionally, are common globally. We assess how overlapping land use allocations impact forest cover change using Peruvian government data for the lowland Amazon. Results are based on propensity score matched difference-in-differences methods using 1-ha resolution forest loss data for 2000–2014, along with Peruvian government land use allocation data. We find that deforestation is lower in overlapping than in same-type, non-overlapping allocations. This finding is consistent across all types of overlapping land use allocations. These results support the hypothesis that multiple use management decreases deforestation, and provide no evidence indicating that overlapping allocations are a form of tenure insecurity that might increase deforestation. Our findings inform conservation policy related to multiple use management, land tenure security, and conflict avoidance.
Planning for Change ANDERSON, CHRISTA M.; WEBER, CHRISTOPHER L.; FABRICIUS, CHRISTO ...
Bioscience,
02/2020, Letnik:
70, Številka:
2
Journal Article
Recenzirano
Odprti dostop
The Intergovernmental Panel on Climate Change's (IPCC) special report on global warming of 1.5 degrees Celsius (°C) makes clear that most scenarios (90%) that hold warming to 1.5°C by 2100 include an ...overshoot, or a period in which the temperature increase exceeds 1.5°C before declining to the end-of-century 1.5°C goal (IPCC 2018). An overshoot is also possible for 2°C scenarios, given the lack of ambition in existing mitigation commitments. Current conservation policy and planning does not adequately account for the high likelihood of a temperature overshoot in a 1.5°C scenario, but the impacts of an overshoot on conservation may be large. Efforts to avoid an overshoot must be increased through more ambitious mitigation commitments and a greater focus on peak warming rather than end-of-century outcomes. Simultaneously, conservation planning should account for such impacts by anticipating more dynamic systems that carry greater uncertainties and potentially irreversible changes that may persist even as temperatures peak and decline.
Celotno besedilo
Dostopno za:
BFBNIB, DOBA, IZUM, KILJ, NMLJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
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•A fully-automated SISCAPA–MALDI-TOF-MS assay was developed for apoA-I and apoB-100.•The assay allowed processing and analysis of 96 samples in one day.•The imprecision (4 replicates, ...5days, 2 sera) was below 5% for both proteins.•Quantification of 93 patient sera agreed well with clinical immunoturbidimetry.•Analytical validation demonstrated selectivity and ruggedness of the assay.
A fully automated workflow was developed and validated for simultaneous quantification of the cardiovascular disease risk markers apolipoproteins A-I (apoA-I) and B-100 (apoB-100) in clinical sera. By coupling of stable-isotope standards and capture by anti-peptide antibodies (SISCAPA) for enrichment of proteotypic peptides from serum digests to matrix-assisted laser desorption/ionization time-of-flight (MALDI-TOF) MS detection, the standardized platform enabled rapid, liquid chromatography-free quantification at a relatively high throughput of 96 samples in 12h. The average imprecision in normo- and triglyceridemic serum pools was 3.8% for apoA-I and 4.2% for apoB-100 (4 replicates over 5days). If stored properly, the MALDI target containing enriched apoA-1 and apoB-100 peptides could be re-analyzed without any effect on bias or imprecision for at least 7days after initial analysis. Validation of the workflow revealed excellent linearity for daily calibration with external, serum-based calibrators (R2 of 0.984 for apoA-I and 0.976 for apoB-100 as average over five days), and absence of matrix effects or interference from triglycerides, protein content, hemolysates, or bilirubins. Quantification of apoA-I in 93 normo- and hypertriglyceridemic clinical sera showed good agreement with immunoturbidimetric analysis (slope=1.01, R2=0.95, mean bias=4.0%). Measurement of apoB-100 in the same clinical sera using both methods, however, revealed several outliers in SISCAPA–MALDI-TOF-MS measurements, possibly as a result of the lower MALDI-TOF-MS signal intensity (slope=1.09, R2=0.91, mean bias=2.0%).
The combination of analytical performance, rapid cycle time and automation potential validate the SISCAPA–MALDI-TOF-MS platform as a valuable approach for standardized and high-throughput quantification of apoA-I and apoB-100 in large sample cohorts.
A variety of policy interventions from public authorities and private companies attempt to reduce deforestation in private forest concessions. These include fines for illegal deforestation and market ...incentives for forest management practices that meet sustainability standards. While some studies have found significant differences in forest outcomes between concessions that participate in sustainability commitments and those that do not, others have found small or inconclusive differences. We contribute to this literature by examining all privately allocated concessions in the Peruvian Amazon to determine whether sustainability commitments correspond with lower deforestation rates. Conversely, we examine whether fines correspond with higher deforestation rates, a question for which fewer analyses have been published. Using matching methods, we do not find significantly different deforestation rates between control groups and logging concessions with third party environmental certification. We also do not see significant differences in deforestation rates in petroleum concessions managed by companies who have made sustainability commitments. Regarding punitive fines, we do not find significant differences in deforestation rates between control groups and logging concessions with fines levied. The same holds true for fines levied in brazil nut concessions. Potential explanations for these findings include insufficient monitoring or inadequate stringency for sustainability commitments, and insufficiently punitive fines or low enforcement levels.
•Sustainability commitments are found for logging and oil concessions in the Peruvian Amazon.•No sustainability commitment are found for rubber or brazil nut concessions.•Sustainability commitments have no significant impact on deforestation rates in the Peruvian Amazon.•Conversely, fines for illegal deforestation do not follow higher deforestation rates in private concessions.
The responses of rare plants to environmental stressors will determine their potential to adapt to a rapidly changing climate. We used a common garden approach to evaluate how six populations of the ...annual San Diego thornmint (Acanthomintha ilicifolia Lamiaceae; listed as endangered in the state of California and as threatened by the US Fish and Wildlife Service) from across the species range respond in terms of growth (biomass, height, and width) and reproduction (seed production, floral production, and next generation seed viability) to experimental differences in water availability. We found a significant irrigation-by-population interaction on the aboveground growth, wherein the differences in the magnitude and direction of treatment did not correlate directly with climate variables in natural populations. With respect to reproduction, the low-irrigation treatment produced more seeds per plant, more reproductive individuals, and a larger proportion of viable seed in most, but not all, populations. The seed production and the effect of irrigation on seed production correlated positively with rainfall at wild source populations. These results suggest that Acanthomintha ilicifolia responds to water limitation by creating more and higher-quality seed, and that plants locally adapted to a higher annual rainfall show a greater plasticity to differences in water availability than plants adapted to a lower annual rainfall, a finding that can inform the in situ demographic management and ex situ collection strategy for Acanthomintha ilicifolia and other rare California annuals.
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