Leaving Rio Branco

We left Rio Branco on Saturday. It was a great trip and yet it was good to come home. I hadn't seen my family for two weeks, and I got a big warm welcome from my kids. The work in Rio Branco was hard, and everyone was a bit exhausted by the end. It took several days to wash off the salt, dirt, and sunscreen. But I will miss the city.

Even more now that I have had a chance to get to know the area, it feels that we were on the edge of civilization, or at least on the edge of developed civilization as we have come to expect. Staying in the city center was a bit disorienting as it is highly developed and not dissimilar from a small-sized American city - lots of restaurants, small shops, bars, civic buildings, etc. Yet just outside of the center the area transitions quickly.

I went for an early morning run on my last day into some of the outskirts of the neighborhood, just 5 or so minutes from our hotel. At one point I found myself along a dirt path running on a hillside through a cluster of small houses. Each was the size of a large living room in the US, with only the bare necessities - a bit of electricity and minimal plumbing. I received a few long stares as I ran through the area. At first, I was a little concerned, but I eventually realized that the stares were more because I was a peculiar novelty in the area.

Most people were beginning their chores as I ran by. Men tinkering with bicycles or other things that needed to be fixed, children playing, and women sweeping in the hours before the hot midday sun. Brazilians have an interesting fascination with cleanliness. Interesting because the climate alternates between extremely dry periods that cause dirt to blow in large clouds, and torrential rains that cause rivers of mud to cascade by. Yet they were out sweeping, and not only their houses, but also the dirt paths in front of their houses to remove litter or leaves that had blown in during the night. There was a curious tranquility to the area that is hard to describe.

After the Burn

While some of the researchers' work was completed yesterday, many of us spent an additional day working at the site doing post-burn sampling. I and my colleague Anne hope to understand the impact of deforestation on the release of mercury to the atmosphere, so it was critical to sample before, during, and especially after the burn to understand how the balance of mercury in the ecosystem has changed. It is a bit early to tell, but our data suggests that deforestation is a big source of mercury to the atmosphere.

The post-burn site is really interesting, most areas are heavily burned with only ash remaining on the ground, but some are largely untouched. What surprised me yesterday was how slowly the fire progressed through the site - it took over an hour to work through the small area we had cleared. What is also surprising is how much biomass remains. Dried leaves, brush, and small branches were by and large completely burned, but most of the large tree trunks remain on the site - though most are scorched. While the fire is now out, some areas of the site are still smoldering as you can see in the background above, and these areas are still very hot. Luckily the area I am working in burned quickly and relatively completely yesterday, so it had cooled off by today - it was only a couple of degrees hotter than the 100 or so that the sun supplied.

Ignition

After several anxious days the weather conditions turned out near perfect today. Skies were clear with only a slight breeze blowing away from the staging area toward the heart of our plot. There were lots of last minute preparations. Several researchers hitched a ride on a military helicopter to measure the spread and intensity of the fire. Several gathered around a station that was pulling smoke and gases from the tower at the center of the fire. Several individuals worked to measure the rate of progression of the fire through the understory. My colleague Anne and I sampled particulate matter to later analyze for mercury and we sampled airborne mercury levels for the first part of the fire. It was really incredible to see after so much work and effort went into this project.

Fingers Crossed

There was a big "meeting of the minds" this morning to discuss the fate of our research. The weather was kind to us yesterday - after the morning rain which, no pun intended, washed out our burn, the sun came out and began to dry things off. This morning we studied regional meteorological reports, rescheduled the firefighters to be on site for tomorrow, rebooked the military helicopter that is on loan to take aerial photos, and shifted all of our schedules for a burn tomorrow at 1 PM. Yet it all comes down to luck, or perhaps fate, so we will be sleeping with our fingers and toes crossed tonight hoping for a dry evening.

We worked at the forest late yesterday evening, taking additional control samples and making sure we have everything we need before the burn. As the sun sets, the forest begins to erupt in a symphony of insects, birds, and other animals singing to us. It is both a bit eerie and extremely beautiful at the same time. This recording does not do it justice, but it gives you a taste of what we hear.

The Forest at Night

Chuva!

The best laid schemes of mice and men go oft awry. 18 researchers, students, and others with hundreds of hours and countless dollars invested in this experiment and it rains. Just a bit of rain, 30 short minutes at about 9:30 this morning. But enough to soak the forest and put our experiment on hold. At this point the weather in the coming days is unclear. Unfortunately it can be difficult to predict weather in this remote corner of Brazil, and what's more, it can change from hour to hour. This morning our fate looked grim, the forecast was for rain all week and it looked like we might complete our time here without a chance to burn the plot. But our luck may be changing. It cleared this afternoon and the sun is baking the forest. If this keeps up through tomorrow, we may be able to carry out the burn on Thursday. If not, we have covered a very small plot with a tarp where I and one other researcher may be able to carry out some limited experiments. However, most of the researchers may be delayed in their work until next year when the dry season returns. It is frustrating, but everyone is trying to stay optimistic. Of course, while the rain throws a kink in our plans, it is welcome by other residents of the forest...

Before the Burn

The treatment phase of this grand experiment begins tomorrow when someone will light a match and start a fire that will burn through the 4 hectare plot of forest that we have been studying. We spent today scrambling around to make sure we have all of the control measurements that we need to compare to the post-fire period. The days are long and hard, but rewarding. Though we are in the Amazon, working in the forest is not bad. It has only rained a bit, so the humidity is not particularly high and the shade from the trees keeps the temperatures at 85-90 F. However, working in the cleared part of the forest can be scorching. We are only about 10 degrees south of the equator, so the sun is stronger than I have ever felt. I worked long August days in Tennessee a few years back, and this makes TN feel like Vermont. Temperatures in the open area can easily reach, or exceed, 100 F. So, it's key to use gobs of strong sunscreen and drink copious amounts of water. By the end of the day, you can find a ring of salt around your collar from the sweat that pours out. But I can't complain, it has been great fun and the work is really rewarding. Tomorrow should be very interesting as we will get to see the fire at work.

Good Sampling Days

We've had lots of hiccups this week. Equipment that never arrived, other items that arrived broken, and still others that work but have required a lot of trouble shooting to get them working well. However, I finally had two very long, exhausting, but excellent days of sampling yesterday and today. Did some great comparisons of an intact forest to the cut forest and we are seeing much higher mercury emissions from the deforested area compared to the intact forest. The burn is scheduled for Tuesday, so it will be interesting to see how that affects the process. Luckily the trip is not all work, and it has been great fun getting to know the other researchers, and other residents of the forest...