When speaking to David Lapola it is hard not to feel both his excitement and frustration. On the one hand, the ecologist from the University of Campinas in Brazil is about to oversee the launch of a pioneering trial deep in the Amazon to see how its trees could respond to increased carbon dioxide in the atmosphere. On the other, what he refers to as the “chamber experiment” is a scaled back version of a truly ground-breaking Free Carbon Air Enrichment (FACE) project that, despite generating major buzz, has hit political headwinds and seen its funding dry up.




FACE, put simply, is method that subjects a given area to higher levels of CO2 and then monitors the growth response of plants or vegetation. The technology has been around for many years. An experiment in the forest managed by Duke University has been yielding results since 1994, while other projects have been used to test a desert ecosystem in Nevada, grasslands in Tasmania, and crops such as soy and wheat. FACE has not yet been deployed in tropical forests, however, despite the hugely important role these forests play in soaking up some of the carbon we humans are dumping into the atmosphere. Which is why Lapola and other researchers were so excited when the Brazilian government first asked them to begin planning for AmazonFACE, at a workshop in Manaus in 2011.



“Scientists have been trying to do this FACE experiment in the tropics for more than 20 years,” Lapola told Earther. “They tried it in the past and some guys gave up because of the logistics. We have come the closest ever.”

As rising CO2 levels drive global temperatures upward, they’re having some curious effects on plants. Plants require carbon in order to do photosynthesis, so more of it should, in theory, stimulate their growth. And indeed, satellite studies indicate that a “greening” of Earth’s land surfaces due to rising CO2 levels is already taking place.

But to say that extra CO2 is a good thing for vegetation, or that it will have long-term benefits, would be far too simplistic. Lapola says a FACE experiment on deciduous forest at the Oak Ridge facility in Tennessee initially saw increased forest growth and production under elevated CO2. But after five or six years, that effect began to recede because of a lack of nutrients in the soil. It’s possible that tropical forests like the Amazon, where trees are chiefly limited by phosphorus, might experience something similar.


“The thing is with forests like the Amazon is that it is not certain at all that they will simply grow faster and fix more carbon from the atmosphere [under elevated CO2],” Bart Kruijt from the University of Wageningen and a member of the AmazonFACE scientific steering committee, told Earther. “We have great big doubts on whether the nutrients in the soil, in particular, will actually sustain that increased growth potential.”

Scientists have been measuring forest growth in the AmazonFACE experimental site from the ground and the canopy. Photo : J. M. Rosa/AmazonFAC

Add in the other effects of climate change, like rising temperatures and longer dry spells which are already impacting tree growth in the Amazon, and the future gets even murkier. Kruijt says the only way to begin to figure out what will happen to the Amazon, whose trees cycle roughly twice as much carbon as humans burn each year, is “by pouring a lot of CO2 into a bit of forest and see what happens.”

After setting up a research plan and international team to oversee AmazonFACE, funding was secured from both the Interamerican Development Bank (IDB) and the Brazilian Ministry of Science in 2014. An area of terra firme—upland non-flooded forest, that generally has nutrient poor soil—was selected 35 miles north of Manaus for the experiment. Kruijt says that while it’s simply impossible to encompass the full range of Amazonian habitats in an experiment like this, the site does represent the most common type of forest.



Two large towers were constructed and instruments installed so that a 30 meter-wide area of forest could be monitored for three years, both from below the ground and in the canopy. Both Kruijt and Lapola hail the success of this so-called pre-experimental baseline phase.


“[T]he scenario is so mad today that I do not have any expectations of that changing anytime soon.”

The next step was to construct to FACE plots within a larger studied area, and then spray them with CO2 until an ambient concentration of 600 parts per million is reached—a level that Earth’s atmosphere as a whole could reach as early as 2050 should emissions remain unchecked. Once 600 ppm was achieved, the forest’s growth and development would be monitored for an initial two-year period.

However, it was at this juncture that funding problems arose. The Brazilian economy had turned south, and the country’s political class were seemingly being toppled or jailed daily in the midst of a corruption crisis following a series of investigations that began in 2014. After further funding was previously received in 2015 from the science ministry and a body associated with the education ministry to cover the vast amount of CO2 required to carry our FACE, political will faded, according to the research team. Lapola says the failure of the science ministry to attend further meetings put off the IDB, whose original deal came to an end in 2017 and which chose not to renew its funding.

“In our case the main difficulty is to get enough funding... the whole experiment is expensive, the infrastructure is expensive, we need people, we need everything and that is not that easy at the moment in Brazil with the politics,” Kruijt said.

The politics he now refers to is the arrival in office this year of the far right populist Jair Bolsonaro. A self-declared fan of Donald Trump who ran on a platform of homophobia, xenophobia, and privatizing the Amazon rainforest, the new president’s administration has already slashed the science ministry’s budget by over 40 percent. His efforts to abandon environmental protections for the Amazon, open swaths of the forest up to industry and kick indigenous people off their lands have led prominent activist and politician Marina Silva to label him an “exterminator of the future.”


Preliminary monitoring in the AmazonFACE study area. Photo : J. M. Rosa/AmazonFACE

Lapola and thousands of other researchers, students and scientists took to the streets nationwide last month in coordinated protests—the largest of their kind against the new president so far— against a raft of controversial cuts including the withdrawal of funding for a national science scholarship program. Bolsonaro’s immediate reaction was reportedly to label demonstrators as “useful idiots”.



Lapola says many members of the initial AmazonFACE research team lost hope the funding would come and moved elsewhere once it appeared the federal government had withdrawn support about two years ago. So as not to see years of hard work come to nothing, a decision was later made to scale back the project and carry out a smaller experiment involving eight aluminum chambers specially constructed around a number of younger trees and saplings.

Beginning at the end of June, four of the constructions will be filled with CO2 50 percent greater than ambient levels—the possible levels we could see in 2050. The other four will have no extra CO2. Lapola believes the experiment, which will last two years, will produce some “good science”.

For the team who have put in the hard yards to get the FACE project where it is the desire to see the full experiment realized remains undimmed.


“This would really help us fill in the knowledge gaps,” Kruijt said. “The proportion [of growth that’s split] between leaves and stems, is it going to change? Are the roots going to develop any strategy to acquire more nutrients from the soil which they are going to need?”

Projects such as AmazonFACE are long-term in scope and ambition. It was initially designed to run for at least ten years, and the goal was to produce results that would influence climate adaptation policy for decades to come. Lapola says that kind of research simply isn’t what funders in Brazil want right now, and that even in good times scientific endeavors take far longer in the Amazon than they would elsewhere given the logistical difficulties of working there.

The stress has been so great that Lapola revealed that shortly after he spoke to Earther he was going to take a break from his role as co-coordinator of the scientific committee. Kruijt has agreed to step in.

“It is indeed very frustrating,” Lapola said. “I have spent eight years of my scientific career on this. It was a big lesson and I learned a lot. I have to be frank, we will keep trying [to do the FACE project] but the scenario is so mad today that I do not have any expectations of that changing anytime soon.”

Earther has reached out to the Brazilian science ministry for comment and we’ll update this post if we hear back.

Advertisement