. In recent years, the pan-Arctic region has experienced
increasingly extreme fire seasons. Fires in the northern high latitudes are
driven by current and future climate change, lightning, fuel conditions, and
human activity. In this context, conceptualizing and parameterizing current
and future Arctic fire regimes will be important for fire and land
management as well as understanding current and predicting future fire
emissions. The objectives of this review were driven by policy questions
identified by the Arctic Monitoring and Assessment Programme (AMAP) Working
Group and posed to its Expert Group on Short-Lived Climate Forcers. This
review synthesizes current understanding of the changing Arctic and boreal
fire regimes, particularly as fire activity and its response to future
climate change in the pan-Arctic have consequences for Arctic Council states
aiming to mitigate and adapt to climate change in the north. The conclusions
from our synthesis are the following. (1) Current and future Arctic fires,
and the adjacent boreal region, are driven by natural (i.e. lightning) and
human-caused ignition sources, including fires caused by timber and energy
extraction, prescribed burning for landscape management, and tourism
activities. Little is published in the scientific literature about cultural
burning by Indigenous populations across the pan-Arctic, and questions remain
on the source of ignitions above 70 ∘  N in Arctic Russia. (2) Climate change is expected to make Arctic fires more likely by increasing
the likelihood of extreme fire weather, increased lightning activity, and
drier vegetative and ground fuel conditions. (3) To some extent, shifting
agricultural land use and forest transitions from forest–steppe to steppe, tundra to taiga, and
coniferous to deciduous in a warmer climate may increase
and decrease open biomass burning, depending on land use in addition to
climate-driven biome shifts. However, at the country and landscape scales,
these relationships are not well established. (4) Current black carbon and
PM 2.5 emissions from wildfires above 50 and 65 ∘  N are larger than emissions from the anthropogenic sectors of residential
combustion, transportation, and flaring. Wildfire emissions
have increased from 2010 to 2020, particularly above 60 ∘  N, with
56 % of black carbon emissions above 65 ∘  N in 2020 attributed to
open biomass burning – indicating how extreme the 2020 wildfire season was
and how severe future Arctic wildfire seasons can potentially be. (5) What
works in the boreal zones to prevent and fight wildfires may not work in the
Arctic. Fire management will need to adapt to a changing climate, economic
development, the Indigenous and local communities, and fragile northern
ecosystems, including permafrost and peatlands. (6) Factors contributing to
the uncertainty of predicting and quantifying future Arctic fire regimes
include underestimation of Arctic fires by satellite systems, lack of
agreement between Earth observations and official statistics, and still
needed refinements of location, conditions, and previous fire return
intervals on peat and permafrost landscapes. This review highlights that
much research is needed in order to understand the local and regional
impacts of the changing Arctic fire regime on emissions and the global
climate, ecosystems, and pan-Arctic communities.

/pdf/reviews-and-syntheses-arctic-fire-regimes-and-emissions-in-3ggq0b828z.pdf

Reviews and syntheses: Arctic fire regimes and emissions in the 21st century

. Methane emissions from boreal and arctic wetlands, lakes, and rivers are
expected to increase in response to warming and associated permafrost thaw.
However, the lack of appropriate land cover datasets for scaling
field-measured methane emissions to circumpolar scales has contributed to a
large uncertainty for our understanding of present-day and future methane
emissions. Here we present the Boreal–Arctic Wetland and Lake Dataset
(BAWLD), a land cover dataset based on an expert assessment, extrapolated
using random forest modelling from available spatial datasets of climate,
topography, soils, permafrost conditions, vegetation, wetlands, and surface
water extents and dynamics. In BAWLD, we estimate the fractional coverage of
five wetland, seven lake, and three river classes within 0.5  ×  0.5 ∘ grid cells that cover the northern boreal and tundra biomes
(17 % of the global land surface). Land cover classes were defined using
criteria that ensured distinct methane emissions among classes, as indicated
by a co-developed comprehensive dataset of methane flux observations. In
BAWLD, wetlands occupied 3.2  ×  10 6  km 2 (14 % of domain)
with a 95 % confidence interval between 2.8 and 3.8  ×  10 6  km 2 . Bog, fen, and permafrost bog were the most abundant wetland
classes, covering ∼  28 % each of the total wetland area,
while the highest-methane-emitting marsh and tundra wetland classes occupied
5 % and 12 %, respectively. Lakes, defined to include all lentic open-water
ecosystems regardless of size, covered 1.4  ×  10 6  km 2 
(6 % of domain). Low-methane-emitting large lakes ( >10  km 2 ) and glacial lakes jointly represented 78 % of the total lake
area, while high-emitting peatland and yedoma lakes covered 18 % and 4 %,
respectively. Small (  km 2 ) glacial, peatland, and yedoma
lakes combined covered 17 % of the total lake area but contributed
disproportionally to the overall spatial uncertainty in lake area with a
95 % confidence interval between 0.15 and 0.38  ×  10 6  km 2 . Rivers and streams were estimated to cover 0.12 ×  10 6  km 2 (0.5 % of domain), of which 8 % was associated with
high-methane-emitting headwaters that drain organic-rich landscapes.
Distinct combinations of spatially co-occurring wetland and lake classes
were identified across the BAWLD domain, allowing for the mapping of
“wetscapes” that have characteristic methane emission magnitudes and
sensitivities to climate change at regional scales. With BAWLD, we provide a
dataset which avoids double-accounting of wetland, lake, and river extents
and which includes confidence intervals for each land cover class. As such,
BAWLD will be suitable for many hydrological and biogeochemical modelling
and upscaling efforts for the northern boreal and arctic region, in
particular those aimed at improving assessments of current and future
methane emissions. Data are freely available at
 https://doi.org/10.18739/A2C824F9X (Olefeldt et al., 2021).

/pdf/the-boreal-arctic-wetland-and-lake-dataset-bawld-fxb2sw3lm2.pdf

The Boreal–Arctic Wetland and Lake Dataset (BAWLD)

There is an increasing recognition that, although the climate change and biodiversity crises are fundamentally connected, they have been primarily addressed independently and a more integrated global approach is essential to tackle these two global challenges. Nature-based Solutions (NbS) are hailed as a pathway for promoting synergies between the climate change and biodiversity agendas. There are, however, uncertainties and difficulties associated with the implementation of NbS, while the evidence regarding their benefits for biodiversity remains limited. We identify five key research areas where incomplete or poor information hinders the development of integrated biodiversity and climate solutions. These relate to refining our understanding of how climate change mitigation and adaptation approaches benefit biodiversity conservation; enhancing our ability to track and predict ecosystems on the move and/or facing collapse; improving our capacity to predict the impacts of climate change on the effectiveness of NbS; developing solutions that match the temporal, spatial and functional scale of the challenges; and developing a comprehensive and practical framework for assessing, and mitigating against, the risks posed by the implementation of NbS. Policy implications. The Conference of the Parties (COP) for the United Nations Framework Convention on Climate Change (COP26) and the Convention on Biological Diversity (COP15) present a clear policy window for developing coherent policy frameworks that align targets across the nexus of biodiversity and climate change. This window should (a) address the substantial and chronic underfunding of global biodiversity conservation, (b) remove financial incentives that negatively impact biodiversity and/or climate change, (c) develop higher levels of integration between the biodiversity and climate change agendas, (d) agree on a monitoring framework that enables the standardised quantification and comparison of biodiversity gains associated with NbS across ecosystems and over time and (e) rethink environmental legislation to better support biodiversity conservation in times of rapid climatic change.

Time to integrate global climate change and biodiversity science-policy agendas

Soil provides a multitude of services that are essential to a healthily functioning biosphere and continuity of the human race, such as feeding the growing human population and the sequestration of carbon needed to counteract global warming. Healthy soil availability is the limiting parameter in the provision of a number of these services. As a result of anthropogenic abuses, and natural and global warming-promoted extreme weather events, Planet Earth is currently experiencing an unprecedented crisis of soil deterioration, desertification and erosive loss that increasingly prejudices the services it provides. Such services are pivotal to the Sustainability Development Goals formulated by the United Nations. Immediate and coordinated action on a global scale is urgently required to slow and ultimately reverse the loss of healthy soils. Despite the 'dirt-dust', non-vital appearance of soil, it is a highly dynamic living entity, whose life is overwhelmingly microbial. The soil microbiota, which constitutes the greatest reservoir and donor of microbial diversity on Earth, acts as a vast bioreactor, mediating a myriad of chemical reactions that turn the biogeochemical cycles, recycle wastes, purify water, and underpin the multitude of other services soil provides. Fuelling the belowground microbial bioreactor is the aboveground plant and photosynthetic surface microbial life which captures solar energy, fixes inorganic CO2 to organic carbon, and channels fixed carbon and energy into soil. In order to muster an effective response to the crisis, to avoid further deterioration, and to restore unhealthy soils, we need a new and coherent approach, namely to deal with soils worldwide as patients in need of health care and create (i) a public health system for development of effective policies for land use, conservation, restoration, recommendations of prophylactic measures, monitoring and identification of problems (epidemiology), organizing crisis responses, etc., and (ii) a healthcare system charged with soil care: the promotion of good practices, implementation of prophylaxis measures, and institution of therapies for treatment of unhealthy soils and restoration of drylands. These systems need to be national but there is also a desperate need for international coordination. To enable development of effective, evidence-based strategies that will underpin the efforts of soil healthcare systems, a substantial investment in wide-ranging interdisciplinary research on soil health and disease is mandatory. This must lead to a level of understanding of the soil:biota functionalities underlying key ecosystem services that enables formulation of effective diagnosis-prophylaxis-therapy pathways for sustainable use, protection and restoration of different types of soil resources in different climatic zones. These conservation-regenerative-restorative measures need to be complemented by an educative-political-economic-legislative framework that provides incentives encouraging soil care: knowledge, policy, economic and others, and laws which promote international adherence to the principles of restorative soil management. And: we must all be engaged in improving soil health; everyone has a duty of care (https://www.bbc.co.uk/ideas/videos/why-soil-is-one-of-the-most-amazing-things-on-eart/p090cf64). Creative application of microbes, microbiomes and microbial biotechnology will be central to the successful operation of the healthcare systems.

https://sfamjournals.onlinelibrary.wiley.com/doi/pdf/10.1111/1751-7915.13771

The soil crisis: the need to treat as a global health problem and the pivotal role of microbes in prophylaxis and therapy.

Natural products from plants have served mankind in a wide range of applications, such as medicines, perfumes, or flavoring agents. For this reason, synthesis, regulation and function of plant-derived chemicals, as well as the evolution of metabolic diversity, has attracted researchers all around the world. In particular, vascular plants have been subject to such analyses due to prevalent characteristics such as appearance, fragrance, and ecological settings. In contrast, bryophytes, constituting the second largest group of plants in terms of species number, have been mostly overlooked in this regard, potentially due to their seemingly tiny, simple and obscure nature. However, the identification of highly interesting chemicals from bryophytes with potential for biotechnological exploitation is changing this perception. Bryophytes offer a high degree of biochemical complexity, as a consequence of their ecological and genetic diversification, which enable them to prosper in various, often very harsh habitats. The number of bioactive compounds isolated from bryophytes is growing rapidly. The rapidly increasing wealth of bryophyte genetics opens doors to functional and comparative genomics approaches, including disentangling of the biosynthesis of potentially interesting chemicals, mining for novel gene families and tracing the evolutionary history of metabolic pathways. Throughout the last decades, the moss Physcomitrella (Physcomitrium patens) has moved from being a model plant together with Marchantia polymorpha in fundamental biology into an attractive host for the production of biotechnologically relevant compounds such as biopharmaceuticals. In the future, bryophytes like the moss P. patens might also be attractive candidates for the production of novel bryophyte-derived chemicals of commercial interest. This review provides a comprehensive overview of natural product research in bryophytes from different perspectives together with biotechnological advances throughout the last decade.

Natural Products from Bryophytes: From Basic Biology to Biotechnological Applications

The carbon balance of peatlands is predicted to shift from a sink to a source this century. However, peatland ecosystems are still omitted from the main Earth system models that are used for future climate change projections, and they are not considered in integrated assessment models that are used in impact and mitigation studies. By using evidence synthesized from the literature and an expert elicitation, we define and quantify the leading drivers of change that have impacted peatland carbon stocks during the Holocene and predict their effect during this century and in the far future. We also identify uncertainties and knowledge gaps in the scientific community and provide insight towards better integration of peatlands into modelling frameworks. Given the importance of the contribution by peatlands to the global carbon cycle, this study shows that peatland science is a critical research area and that we still have a long way to go to fully understand the peatland–carbon–climate nexus. Peatlands are impacted by climate and land-use changes, with feedback to warming by acting as either sources or sinks of carbon. Expert elicitation combined with literature review reveals key drivers of change that alter peatland carbon dynamics, with implications for improving models.

/pdf/expert-assessment-of-future-vulnerability-of-the-global-31nv6knqsu.pdf

J. C. Benavides

Papers

Expert assessment of future vulnerability of the global peatland carbon sink