50th lab paper! The LAST Coring Platform You Will Ever Need: Light, Affordable, Stable, and Transportable

We are very happy to share this technical note about our lab coring platform design published recently in Quaternary: Blarquez O. and Aleman J. C. 2020. The LAST coring platform you will ever need: Light, Affordable, Stable, and Transportable. Quaternary, 3, 27. https://doi.org/10.3390/quat3030027  

The paper is accessible in open access from the Quaternary website https://doi.org/10.3390/quat3030027 and the coring platform plan are available here: https://www.mdpi.com/2571-550X/3/3/27/s1 or here: quaternary-03-00027-s001

Abstract: Coring lakes and water bodies for paleoecological studies often involves using a coring platform to properly operate a sediment sampling device. In the past, coring platforms have been developed by specific paleoecology laboratories or by private companies. Those coring platforms are generally composed of two boats (inflatable boats, kayaks, etc.) connected together by a metallic and wood structure. While these coring platforms have proven their efficacy, they are not ideal in several coring settings requiring remote transportation, and their cost may be prohibitive for less funded paleoecological laboratories. On this technical note, we describe the Light, Affordable, Stable, and Transportable (LAST) coring platform. Coring platforms based on these principles and on the design presented herein have been extensively tested in various conditions and countries by our research group and collaborators. In the first part of this manuscript, we present the principles and the design of the LAST coring platform; then, we discuss the coring setting for which the LAST coring platform is suitable, and its possible limitations. Associated with this manuscript, we provide a construction and assemblage manual developed without words and with simple illustrations in order to make it easily accessible to speakers of any language. 



New paper: Paleolimnological assessment of wildfire‐derived atmospheric deposition of trace metal(loid)s and major ions to subarctic lakes (Northwest Territories, Canada)

I am very pleased to share this article by Nicolas Pelletier about fires and trace metal(loid)s in the Northwest Territories:

Pelletier N., Chételat J., Blarquez O., & Vermaire J. C. (2020). Paleolimnological assessment of wildfire‐derived atmospheric deposition of trace metal(loid)s and major ions to subarctic lakes (Northwest Territories, Canada). Journal of Geophysical Research: Biogeosciences, 125, e2020JG005720. https://doi.org/10.1029/2020JG005720

You can find the paper here https://doi.org/10.1029/2020JG005720 and here 

Plain language summary:

The subarctic boreal forest is facing major changes in fire regimes in response to climate change, and it is predicted that wildfires will become increasingly frequent and
severe in the near future. Wildfires release terrestrial elements to the atmosphere as aerosols, and the impact of ash fallout from local fires on metal(loid) deposition is not well characterized. Wildfire fallouts contain certain elements that can be essential to living organisms (e.g., Ca, Mg, Mn, and Fe) and others that can be toxic (e.g., Pb, Hg, Cd, and As). In this research, we used lake sediment to estimate the amount of material deposited by wildfires in lakes of the subarctic boreal forest over the last 150 years. We found that the input of major ions (e.g., Na, Mg, Ca, and K), metals (e.g., Pb, Hg, Al, and Fe), and metalloids (As and Sb) was elevated during wildfire periods but only by a small amount. The impact of atmospheric deposition was observable in sediment records, indicating that element accumulation in lake sediment can be influenced by wildfires occurring outside the catchment. This study suggests that large areas, including many lakes, will receive additional metal, metalloid, and major ion inputs from more frequent wildfire fallout.

New paper: The reconstruction of burned area and fire severity using charcoal from boreal lake sediments

We are pleased to share the last lab paper by Andy Hennebelle: Hennebelle, A., Aleman, J. C., Ali, A. A., Bergeron, Y., Carcaillet, C., Grondin, P., Landry J. & Blarquez, O. (2020). The reconstruction of burned area and fire severity using charcoal from boreal lake sediments. The Holocene, 0959683620932979.

You can find the paper here https://doi.org/10.1177/0959683620932979 and here 

Although lacustrine sedimentary charcoal has long been used to infer paleofires, their quantitative reconstructions require improvements of the calibration of their links with fire regimes (i.e. occurrence, area, and severity) and the taphonomic processes that affect charcoal particles between the production and the deposition in lake sediments. Charcoal particles >150 µm were monitored yearly from 2011 to 2016 using traps submerged in seven head lakes situated in flat-to-rolling boreal forest landscapes in eastern Canada. The burned area was measured, and the above-ground fire severity was assessed using the differentiated normalized burn ratio (dNBR) index, derived from LANDSAT images, and measurements taken within zones radiating 3, 15, and 30 km from the lakes. In order to evaluate potential lag effects in the charcoal record, fire metrics were assessed for the year of recorded charcoal recording (lag 0) and up to 5 years before charcoal deposition (lag 5). A total of 92 variables were generated and sorted using a Random Forest-based methodology. The most explanatory variables for annual charcoal particle presence, expressed as the median surface area, were selected. Results show that, temporally, sedimentary charcoal accurately recorded fire events without a temporal lag; spatially, fires were recorded up to 30 km from the lakes. Selected variables highlighted the importance of burned area and fire severity in explaining lacustrine charcoal. The charcoal influx was thus driven by fire area and severity during the production process. The dispersion process of particles resulted mostly of wind transportation within the regional (<30 km) source area. Overall, charcoal median surface area represents a reliable proxy for reconstructing past burned areas and fire severities.

Researchers see need for action on forest fire risk

New statistical approach: changes in forest fires in the 19th and 20th centuries were man-made

How do humans affect forest fires? And what can we learn from forest fires in the past for the future of forestry? An international team of researchers led by Elisabeth Dietze, formerly at the German Research Centre for Geosciences GFZ in Potsdam and now at the Alfred Wegener Institute – Helmholtz Centre for Polar and Marine Research, now provides new answers to these questions. The research team has shown for a region in north-eastern Poland that forest fires increasingly occurred there after the end of the 18th century with the change to organised forestry. Among other things, the conversion of forests into pine monocultures played a role. The increased number of fires subsequently made it necessary to manage and maintain the forests differently. The researchers report on this in the journalPLOS ONE.

Every natural landscape has its own pattern of how fires behave there. This pattern is also known as the “fire regime”. Fire regimes are directly linked to the landscape, its vegetation and climate. Humans can change these regimes by managing a landscape. However, little is yet known about how they influenced fire regimes before the beginning of active forest fire fighting. Among the past 250 years, the human contribution to the global increase in fires during the mid- 19th century is particularly unclear, as the data available for this period is not comprehensive.

In the study published now, the researchers examined the extent to which forest management influenced the fire regime in a temperate forest landscape around Lake Czechowskie in the Bory Tucholskie (English:Tuchola Forest). Bory Tucholskie located in north-eastern Poland is one of the largest forest areas of Central Europe. The researchers combined evidence from various sources, such as pieces of charcoal and molecules formed during biomass combustion, so-called molecular fire markers. The investigated material originated from drilling cores of lake sediments. The researchers applied a new statistical approach to the classification of fires to their samples. They compared their measurements with independent climate and vegetation reconstructions and historical records.

Adaptation needs in the context of climate change

The team found two striking changes in the fire regime in the 19th and 20th centuries, both of which were driven by man. Accordingly, the amount of biomass burned unintentionally increased during the mid-19th century. At that time, the flammable, fast-growing pine monocultures necessary for industrialisation were planted.“After devastating fires in 1863, fire became an important factor in forest management,”explains Elisabeth Dietze.

At the end of the 19th century, state forestry reacted with an active fire prevention strategy. Various measures, such as a denser network of paths, were used to prevent fires. These measures had been very effective over the 20th century and the number of fires had decreased. But after the collapse of the Soviet Union, more pine trees were planted again in the 1990s. The forested area had increased.“In the course of climate change with its temperature rise and more frequent dry summers a new adjustment of forestry is necessary. Fires should be suppressed more effectively in the future and the forest should be restructured – towards more diverse and less flammable tree and shrub species. This is our most important result for forestry,”says Elisabeth Dietze.

With the new findings, models for predicting fires can be better calibrated.“We can reconstruct fire types more comprehensively than before,”says Elisabeth Dietze.“Even low-intensity fires, such as typical ground fires in contrast to crown fires, can be detected with molecular fire markers, which was not possible with charcoal alone.”

The study is a cooperation between scientists from the Netherlands and Canada and partners in ‘ICLEA – Virtual Institute for Integrated Climate and Landscape Development Analysis’. As partners the GFZ, the Ernst Moritz Arndt University Greifswald, the Brandenburg Technical University Cottbus together with the Polish Academy of Sciences bundle their research capacities and expertise to investigate the climate and landscape development of the historical cultural landscape between North East Germany and North West Poland.

Original study:
Dietze, E., Brykała,D., SchreuderL.T. et al., 2019. Human-induced fire regime shifts during 19thcentury industrialization: a robust fire regime reconstruction using northern Polish lake sediments.PLOS ONE. DOI: 10.1371/journal.pone.0222011


Sediments from Lake Czechowskie in the Tuchola Forest, Poland, allow for the high-resolution reconstruction of past forest fires in a region dominated by pine monocultures sensitive to the ongoing environmental change (Photo: D. Brykała, Polish Academy of Science).

Further information:

ICLEA – Virtual Institute of Integrated Climate and Landscape Evolution Analyses

New paper: Palaeo-trajectories of forest savannization in the southern Congo

I am pleased to share the last lab paper leaded by Julie Aleman: 

Julie C. Aleman, Olivier Blarquez, Hilaire Elenga, Jordan Paillard, Victor Kimpuni, Gaubin Itoua, Gauthier Issele, A. Carla Staver. 2019. Palaeo-trajectories of forest savannization in the southern Congo. Biology Letters. 15. http://doi.org/10.1098/rsbl.2019.0284 

The paper follows our 2015 fieldwork in the Republic of the Congo where we cored the Ngofouo lake:

Ngofouo lake.

Savanna surrounding the lake.

The ceremony before coring the lake.

Coring team.

Featured image: Savana fire burning near the forest edge in the Pool province in August 2015. 

Tropical savannah and forest are thought to represent alternative stable states in ecosystem structure in some climates. The implication is that biomes are maintained by positive feedbacks, e.g. with fire, and that historical distributions could play a role in determining modern ones. In this context, climate alone does not govern transitions between biomes, and understanding the causes and pathways of such transitions becomes crucial. Here, we use a multi-proxy analysis of a 2000-year core to evaluate modes of transition in vegetation structure and fire regimes. We demonstrate a first transition ca 1540 BP, when a cyclic fire regime entered a forested landscape, eventually resulting, by ca 1060 BP, in a transition to a more open savannah-like or mosaicked structure. This pattern may parallel currently accelerating fire regimes in tropical forests suggesting that fires can savannize forests, but perhaps more slowly than feared. Finally, ca 540 BP, a drought combined with anthropogenic influences resulted in a conclusive transition to savannah, probably resembling the modern landscape in the region. We show here that fire interacted with drought to transition forest to savannah, suggesting that disturbance by fire can be a major driver of biome change.

Letter: Glacial refugia in the south‐western Alps?

Find out our last letter in New Phytologist with Christopher Carcaillet: Glacial refugia in the south‐western Alps? a response to Finsinger et al. (2019) ‘Fire on ice and frozen trees? Inappropriate radiocarbon dating leads to unrealistic reconstructions. 

Your can download the pdf here  or on the revue website: http://doi.wiley.com/10.1111/nph.15673

Ref: Carcaillet C. and Blarquez O. 2019. Glacial refugia in the south-western Alps? New Phytologist, 14. http://doi.wiley.com/10.1111/nph.15673 

New paper: Taking Fire Science and Practice to the Next Level: Report from the PAGES Global Paleofire Working Group Workshop 2017 in Montreal, Canada – Paleofire Knowledge for Current and Future Ecosystem Management

I am glad to share the last paper from the GPWG Workshop in Montreal by Katarzyna et al. on the dialogue between stakeholders and paleofire researchers:
Marcisz K., Vannière B., Blarquez O. & the GPWG2. 2018. Taking Fire Science and Practice to the Next Level: Report from the PAGES Global Paleofire Working Group Workshop 2017 in Montreal, Canada – Paleofire Knowledge for Current and Future Ecosystem Management. Open Quaternary, 4(1), 7. http://doi.org/10.5334/oq.44
This report summarizes the outcome of the PAGES Global Paleofire Working Group workshop 2017 that took place in Montreal, Canada – Paleofire knowledge for current and future ecosystem management. The workshop aimed to (1) discuss the importance of past fire or paleofire research, focused on long-term influence of fire on the environments worldwide, in nature conservation, (2) find ways to integrate scientific achievements of paleofire research into ecosystem management practices, and (3) start the dialogue with ecosystem managers, practitioners and policymakers (EMPPs). With this report, the members of the Global Paleofire Working Group would like to open a discussion about how igniting new collaborations with EMPPs and make paleofire data useful for fire risk management. We recognized four main challenges in communication and cooperation between scientists and EMPPs: little awareness of EMPPs about paleofire research, differences in professional language used in an operational context by scientists and EMPPs, scientific data availability, and costs of paleoecological expertise. Moreover, we indicate the way to improve the communication between scientists and EMPPs by proposing a scheme of cooperation between both groups. We want to encourage researchers working in various fields of paleoecology to open up for the cooperation with EMPPs in the future, especially helping to create ecosystem management plans, because paleoecological data carry important information about the evolution of ecosystems that is vital in the context of global change.

New Paper: Using paleoecology to improve reference conditions for ecosystem-based management in western spruce-moss subdomain of Québec

I am very pleased to shared the first paper of Andy Hennebelle PhD dealing with management and paleoecology in the spruce forest of Québec: 

Hennebelle A., Grondin P., Aleman J. C., Ali A. A., Bergeron Y., Borcard D., & Blarquez O. 2018. Using paleoecology to improve reference conditions for ecosystem-based management in western spruce-moss subdomain of Québec. Forest Ecology and Management, 430, 157–165. https://doi.org/10.1016/j.foreco.2018.08.007 


Ecosystem based management in Québec is framed by reference conditions defining percentage of old-growth forest (> 100-years-old) and forest composition characterizing pre-industrial forest landscapes. In the western spruce-moss bioclimatic subdomain (154 184 km2) a fire cycle estimated at 150 years was used to target that 49% of the landscape has to be composed of old-growth forest. Yet, this target was developed using past (19th–20th C.) climate and vegetation data and assume that environment and ecosystem processes are homo- geneous for the entire western spruce-moss bioclimatic subdomain. The wide spatial and narrow temporal windows limit the application of reference conditions under ongoing climate change.

Our aim was to classify current vegetation heterogeneity of the western spruce-moss subdomain into homogeneous zones and to study the long-term history of fire and vegetation within these zones. This approach will help to refine forest management targets that are based upon short-term records by providing a long-term perspective that is needed for the forests to be managed within their natural range of variability. Modern forest inventories data were used along with climate, physical variables, and natural and human disturbances to study the current vegetation-environment interactions among the western spruce-moss subdomain. We also used 18 published sedimentary pollen and charcoal series to reconstruct Holocene vegetation and Fire Return Intervals (FRI).

Contemporary data revealed 4 zones with homogeneous interactions between vegetation and environment. Pollen analysis revealed three long-term vegetation paths: early successional species dominance, late to early species transition and late successional species dominance. These suggest that modern forest composition results from Holocene trajectories occurring within each zone. Holocene mean FRI (mFRI) ranged from 222 to 258 years across the subdomain, resulting in old-growth forests ranging between 64% and 68%, depending upon the zone.

Paleoecological and contemporary results support that to make forest management more sustainable, current landscape heterogeneity that arises from millennial forest composition trajectories and fire cycle dynamics should be taken into account by down-scaling the previously established reference conditions.

New Paper: The climate, the fuel and the land use: long-term regional variability of biomass burning in boreal forests

I am very happy to share this new paper about fire regime variability between Scandinavia and North America by Chiara Molinari and colleagues:

Molinari C., Lehsten V., Blarquez O., Carcaillet C., Davis B. A. S., Kaplan J. O., Clear J., Bradshaw R. H. W. 2018. The climate, the fuel and the land use: long-term regional variability of biomass burning in boreal forests. Global Change Biology, 1–18. https://doi.org/10.1111/gcb.14380 


The influence of different drivers on changes in North American and European bor- eal forests biomass burning (BB) during the Holocene was investigated based on the following hypotheses: land use was important only in the southernmost regions, while elsewhere climate was the main driver modulated by changes in fuel type. BB was reconstructed by means of 88 sedimentary charcoal records divided into six dif- ferent site clusters. A statistical approach was used to explore the relative contribu- tion of (a) pollen‐based mean July/summer temperature and mean annual precipitation reconstructions, (b) an independent model‐based scenario of past land use (LU), and (c) pollen‐based reconstructions of plant functional types (PFTs) on BB. Our hypotheses were tested with: (a) a west‐east northern boreal sector with changing climatic conditions and a homogeneous vegetation, and (b) a north‐south European boreal sector characterized by gradual variation in both climate and vege- tation composition. The processes driving BB in boreal forests varied from one region to another during the Holocene. However, general trends in boreal biomass burning were primarily controlled by changes in climate (mean annual precipitation in Alaska, northern Quebec, and northern Fennoscandia, and mean July/summer temperature in central Canada and central Fennoscandia) and, secondarily, by fuel composition (BB positively correlated with the presence of boreal needleleaf ever- green trees in Alaska and in central and southern Fennoscandia). Land use played only a marginal role. A modification towards less flammable tree species (by promot- ing deciduous stands over fire‐prone conifers) could contribute to reduce circumbo- real wildfire risk in future warmer periods.

New paper: Guidelines for the use and interpretation of palaeofire reconstructions based on various archives and proxies

I am pleased to share this recent article by Cecile Remy and colleagues on the comparison of charcoal records using various archives:

Remy C. C., Fouquemberg C., Asselin H., Andrieux B., Magnan G., Brossier B., Grondin P., Bergeron Y., Talon B., Girardin M. P., Blarquez O., Bajolle L., Ali A. A. (2018). Guidelines for the use and interpretation of palaeofire reconstructions based on various archives and proxies. Quaternary Science Reviews, 193, 312-322.  https://doi.org/10.1016/j.quascirev.2018.06.010 


We present a comparative analysis of fire reconstructions from tree rings and from wood charcoal preserved in forest soils, peat and lake sediments. Our objective is to highlight the benefits and limits of different archives and proxies to reconstruct fire histories. We propose guidelines to optimize proxy and archive choice in terms of spatial and temporal scales of interest. Comparisons were performed for two sites in the boreal forest of northeastern North America. Compared to others archives, tree-ring analysis remains the best choice to reconstruct recent fires (<1000 years). For longer periods (from several centuries to millennia), lake charcoal can be used to reconstruct regional or local fire histories depending on the method used, but the focus should be on historical trends rather than on the identification of individual fire events. Charcoal preserved in peat and soils can be used to identify individual fire, but sometimes cover shorter time periods than lake archives.



WORKSHOP REPORT: Applying paleofire records in ecological management

We are very glad to share the last report from the GPWG2 Montreal Workshop that is now published in Wildfire Magazine.

WORKSHOP REPORT: Applying paleofire records in ecological management, by: Kendrick J. Brown – Natural Resources Canada, Mitchell J. Power – University of Utah, Michal Słowiński – Polish Academy of Sciences, Andri C. Van Aardt – University of the Free State, Olivier Blarquez – Université de Montréal, Pierre Grondin – Ministère de la Forêt, de la Faune et des Parcs.

You can read the workshop report below or directly on Wildfire Magazine Here.

New paper: Late Holocene influence of societies on the fire regime in southern Québec temperate forests

I am really happy to share our last paper published in Quaternary Science Reviews with students and colleagues from the Department of Geography and Anthropology of UdeM:

Blarquez O., Talbot J., Paillard J., Lapointe-Elmrabti L., Pelletier N., Gates St-Pierre C. 2018. Late Holocene influence of societies on the fire regime in southern Québec temperate forests. Quaternary Science Reviews 180: 63–74. doi:10.1016/j.quascirev.2017.11.022  

Data will follow soon… 

Abstract: Climatic change that occurred during the Holocene is often recognized as the main factor for explaining fire dynamics, while the influence of human societies is less apparent. In eastern North America, human influence on fire regime before European settlement has been debated, mainly because of a paucity of sites and paleoecological techniques that can distinguish human influences unequivocally from climate. We applied a multiproxy analysis to a 12 000-year-old paleoecological sequence from a site in the vicinity of known settlement areas that were occupied over more than 7000 years. From this analysis, we were able detect the human influence on the fire regime before and after European colonization. Fire occurrence and fire return intervals (FRI) were based on analysis of sedimentary charcoals at a high temporal and spatial resolution. Fire occurrence was then compared to vegetation that was reconstructed from pollen analysis, from population densities deduced from archeological site dating, from demographic and technological models, and from climate reconstructed using general circulation models and ice-core isotopes. Holocene mean FRI was short (164 ± 134 years) and associated with small charcoal peaks that were likely indicative of surface fires affecting small areas. After 1500 BP, large vegetation changes and human demographic growth that was demonstrated through increased settlement evidence likely caused the observed FRI lengthening (301 ± 201 years), which occurred without significant changes in climate. Permanent settlement by Europeans in the area around 1800 AD was followed by a substantial demographic increase, leading to the establishment of Gatineau, Hull and Ottawa. This trend was accompanied by a shift in the charcoal record toward anthropogenic particles that were reflective of fossil fuel burning and an apparent absence of wood charcoal that would be indicative of complete fire suppression. An anthropogenic fire regime that was characterized by severe and large fires and long fire-return intervals occurred more than 1000 years ago, concomitant with the spread of native agriculture, which intensified with European colonization over the past two centuries.

Winter is coming

Notre dernière étude publiée dans New Phytologist fait la couverture du journal!

Le blog du journal nous fait également l’honneur d’un article par Mike Whitfield que vous trouverez ici: https://www.newphytologist.org/blog/behind-the-cover-new-phytologist-2164-december-2017/ 

Et repris ci dessous:

Winter has come to Lake Miroir. Below the surface, deep down in the dark, the lakebed sediments tell a story of ice and fire.

These days, snow covers the landscape from December to April, but this hasn’t always been the case. This lake contains sediments from the last glaciation, which ended about 15,000 years ago in the Alps. Interestingly these sediments contain proof of a glacial refugia of trees: cembra pines and larch. Trees survived the deep glacial winter here in isolation.

The snowy scene on the cover of New Phytologist 216:4 represents a site that contains proof of an extraordinary interplay between fire and vegetation in a periglacial environment. Christopher Carcaillet and Olivier Blarquez studied lake sediments nine metres below the surface. In their New Phytologistpaper, they describe how they discovered evidence of fire amid the ice. This refuge burned, with a very low frequency of about one fire per 1000 years. This is the first evidence of fire at such high altitude during glacial times, which were cold and dry.

Image: Lake Miroir, western Alps, France.
Lake Miroir, western Alps, France. Courtesy of Christopher Carcaillet.

Today, fire is about three times more frequent, with one fire every 300 years or so. The vegetation is naturally dominated by larch with cembra pines. While larch abound today, during glacial times the cembra pines were dominant. Carcaillet and Blarquez observed that when the vegetation switched from pine dominant to larch dominant, fires became more frequent. These results suggest that vegetation and fire interact, fire controlling the abundance of larch over cembra pine.

Christopher Carcaillet’s research focuses on determining the long-term relative influences of climate and social processes on the pattern of plant communities (e.g. biodiversity) or ecosystem dynamics through changes in disturbance regimes (such as fire, snow avalanche, or insect outbreak). Seeking similar evidence to that found at Lake Miroir, the researchers investigated a similar lake in the same region. While it also contains glacial sediments, it provides no evidence of trees nor of fire. This comparison shows that glacial climate does not prevent the occurrence of fires, but suggests that trees are needed to allow fires to ignite and spread.

Carcaillet and Blarquez’s research suggests that trees may have survived the long glacial winter in Europe in more places than previously thought. Despite finding refuge from the ice, however, they may not have been safe from fire.

Mike Whitfield
Development Coordinator
New Phytologist

Read the paper: Carcaillet, C. and Blarquez, O. (2017) Fire ecology of a tree glacial refugium on a nunatak with a view on Alpine glaciers. New Phytologist. doi: 10.1111/nph.14721


Our paper on African land-use change recommended in F1000Prime as being of special significance in its field!

Our paper “Land-use change outweighs projected effects of changing rainfall on tree cover in sub-Saharan Africa”  , has been recommended in F1000Prime as being of special significance in its field by F1000 Faculty Member George Malanson! Pr. Malanson summary:

Aleman et al. identified landscapes at risk in sub-Saharan Africa. A variety of data sources (satellite tree cover, climatic, soils, population density, and land use) are nicely combined in a statistical model (random forest) to identify the relative importance of variables. Future scenarios were developed and the random forest model re-used to predict future tree cover. Land use change was identified as a greater threat than climate change. Risk is assessed in terms of loss of tree cover and areas likely to be protected. Depending on scenario, projected loss of tree cover was high in both savanna and forest biomes, but tree cover increases could reduce the area of savanna. The highest risk is in an area south of the Sahel and with a connection to much of the Congo Basin. Given the role of land use, the conversion of savanna to biofuels to mitigate climate change is questioned. The paper could be used as an example for complementary analyses in other places. The focus on biome transitions (forest-savanna-grassland) in the context of land use highlights the importance of landscape level analyses. The action is at the edges.