Greg Asner: Ecology from the air

84,693 views ・ 2013-11-19

TED


Please double-click on the English subtitles below to play the video.

00:12
Technology can change our understanding of nature.
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Take for example the case of lions.
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For centuries, it's been said that female lions
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do all of the hunting out in the open savanna,
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and male lions do nothing until it's time for dinner.
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You've heard this too, I can tell.
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Well recently, I led an airborne mapping campaign
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in the Kruger National Park in South Africa.
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Our colleagues put GPS tracking collars
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on male and female lions,
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and we mapped their hunting behavior
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from the air.
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The lower left shows a lion sizing up
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a herd of impala for a kill,
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and the right shows what I call
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the lion viewshed.
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That's how far the lion can see in all directions
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until his or her view is obstructed by vegetation.
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And what we found
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is that male lions are not the lazy hunters
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we thought them to be.
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They just use a different strategy.
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Whereas the female lions hunt
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out in the open savanna
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over long distances, usually during the day,
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male lions use an ambush strategy
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in dense vegetation, and often at night.
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This video shows the actual hunting viewsheds
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of male lions on the left
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and females on the right.
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Red and darker colors show more dense vegetation,
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and the white are wide open spaces.
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And this is the viewshed right literally at the eye level
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of hunting male and female lions.
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All of a sudden, you get a very clear understanding
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of the very spooky conditions under which
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male lions do their hunting.
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I bring up this example to begin,
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because it emphasizes how little we know about nature.
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There's been a huge amount of work done so far
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to try to slow down our losses of tropical forests,
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and we are losing our forests at a rapid rate,
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as shown in red on the slide.
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I find it ironic that we're doing so much,
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yet these areas are fairly unknown to science.
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So how can we save what we don't understand?
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Now I'm a global ecologist and an Earth explorer
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with a background in physics and chemistry
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and biology and a lot of other boring subjects,
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but above all, I'm obsessed with what we don't know
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about our planet.
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So I created this,
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the Carnegie Airborne Observatory, or CAO.
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It may look like a plane with a fancy paint job,
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but I packed it with over 1,000 kilos
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of high-tech sensors, computers,
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and a very motivated staff
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of Earth scientists and pilots.
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Two of our instruments are very unique:
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one is called an imaging spectrometer
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that can actually measure the chemical composition
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of plants as we fly over them.
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Another one is a set of lasers,
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very high-powered lasers,
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that fire out of the bottom of the plane,
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sweeping across the ecosystem
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and measuring it at nearly 500,000 times per second
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in high-resolution 3D.
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Here's an image of the Golden Gate Bridge
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in San Francisco, not far from where I live.
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Although we flew straight over this bridge,
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we imaged it in 3D, captured its color
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in just a few seconds.
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But the real power of the CAO
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is its ability to capture the actual building blocks
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of ecosystems.
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This is a small town in the Amazon,
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imaged with the CAO.
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We can slice through our data
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and see, for example, the 3D structure
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of the vegetation and the buildings,
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or we can use the chemical information
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to actually figure out how fast the plants are growing
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as we fly over them.
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The hottest pinks are the fastest-growing plants.
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And we can see biodiversity in ways
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that you never could have imagined.
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This is what a rainforest might look like
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as you fly over it in a hot air balloon.
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This is how we see a rainforest,
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in kaleidoscopic color that tells us
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that there are many species living with one another.
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But you have to remember that these trees
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are literally bigger than whales,
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and what that means is that they're impossible to understand
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just by walking on the ground below them.
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So our imagery is 3D, it's chemical, it's biological,
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and this tells us not only the species
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that are living in the canopy,
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but it tells us a lot of information
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about the rest of the species that occupy the rainforest.
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Now I created the CAO
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in order to answer questions that have proven
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extremely challenging to answer from any other vantage point,
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such as from the ground, or from satellite sensors.
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I want to share three of those questions with you today.
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The first questions is,
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how do we manage our carbon reserves
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in tropical forests?
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Tropical forests contain a huge amount of carbon in the trees,
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and we need to keep that carbon in those forests
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if we're going to avoid any further global warming.
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Unfortunately, global carbon emissions
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from deforestation
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now equals the global transportation sector.
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That's all ships, airplanes, trains and automobiles combined.
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So it's understandable that policy negotiators
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have been working hard to reduce deforestation,
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but they're doing it on landscapes
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that are hardly known to science.
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If you don't know where the carbon is exactly,
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in detail, how can you know what you're losing?
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Basically, we need a high-tech accounting system.
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With our system, we're able to see the carbon stocks
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of tropical forests in utter detail.
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The red shows, obviously, closed-canopy tropical forest,
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and then you see the cookie cutting,
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or the cutting of the forest in yellows and greens.
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It's like cutting a cake except this cake
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is about whale deep.
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And yet, we can zoom in and see the forest
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and the trees at the same time.
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And what's amazing is, even though we flew
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very high above this forest,
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later on in analysis, we can go in
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and actually experience the treetrops,
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leaf by leaf, branch by branch,
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just as the other species that live in this forest
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experience it along with the trees themselves.
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We've been using the technology to explore
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and to actually put out the first carbon geographies
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in high resolution
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in faraway places like the Amazon Basin
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and not-so-faraway places like the United States
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and Central America.
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What I'm going to do is I'm going to take you on a high-resolution, first-time tour
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of the carbon landscapes of Peru and then Panama.
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The colors are going to be going from red to blue.
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Red is extremely high carbon stocks,
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your largest cathedral forests you can imagine,
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and blue are very low carbon stocks.
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And let me tell you, Peru alone is an amazing place,
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totally unknown in terms of its carbon geography
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until today.
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We can fly to this area in northern Peru
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and see super high carbon stocks in red,
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and the Amazon River and floodplain
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cutting right through it.
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We can go to an area of utter devastation
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caused by deforestation in blue,
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and the virus of deforestation spreading out in orange.
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We can also fly to the southern Andes
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to see the tree line and see exactly how
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the carbon geography ends
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as we go up into the mountain system.
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And we can go to the biggest swamp in the western Amazon.
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It's a watery dreamworld
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akin to Jim Cameron's "Avatar."
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We can go to one of the smallest tropical countries,
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Panama, and see also a huge range
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of carbon variation,
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from high in red to low in blue.
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Unfortunately, most of the carbon is lost in the lowlands,
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but what you see that's left,
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in terms of high carbon stocks in greens and reds,
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is the stuff that's up in the mountains.
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One interesting exception to this
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is right in the middle of your screen.
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You're seeing the buffer zone around the Panama Canal.
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That's in the reds and yellows.
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The canal authorities are using force
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to protect their watershed and global commerce.
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This kind of carbon mapping
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has transformed conservation
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and resource policy development.
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It's really advancing our ability to save forests
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and to curb climate change.
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My second question: How do we prepare for climate change
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in a place like the Amazon rainforest?
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Let me tell you, I spend a lot of time
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in these places, and we're seeing the climate changing already.
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Temperatures are increasing,
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and what's really happening is we're getting a lot of droughts,
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recurring droughts.
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The 2010 mega-drought is shown here
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with red showing an area about the size of Western Europe.
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The Amazon was so dry in 2010
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that even the main stem of the Amazon river itself
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dried up partially, as you see in the photo
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in the lower portion of the slide.
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What we found is that in very remote areas,
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these droughts are having a big negative impact
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on tropical forests.
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For example, these are all of the dead trees in red
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that suffered mortality following the 2010 drought.
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This area happens to be on the border
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of Peru and Brazil,
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totally unexplored,
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almost totally unknown scientifically.
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So what we think, as Earth scientists,
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is species are going to have to migrate
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with climate change from the east in Brazil
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all the way west into the Andes
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and up into the mountains
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in order to minimize their exposure to climate change.
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One of the problems with this is that humans
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are taking apart the western Amazon as we speak.
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Look at this 100-square-kilometer gash
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in the forest created by gold miners.
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You see the forest in green in 3D,
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and you see the effects of gold mining
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down below the soil surface.
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Species have nowhere to migrate in a system like this, obviously.
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If you haven't been to the Amazon, you should go.
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It's an amazing experience every time,
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no matter where you go.
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You're going to probably see it this way, on a river.
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But what happens is a lot of times
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the rivers hide what's really going on
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back in the forest itself.
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We flew over this same river,
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imaged the system in 3D.
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The forest is on the left.
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And then we can digitally remove the forest
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and see what's going on below the canopy.
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And in this case, we found gold mining activity,
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all of it illegal,
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set back away from the river's edge,
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as you'll see in those strange pockmarks
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coming up on your screen on the right.
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Don't worry, we're working with the authorities
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to deal with this and many, many other problems
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in the region.
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So in order to put together a conservation plan
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for these unique, important corridors
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like the western Amazon and the Andes Amazon corridor,
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we have to start making
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geographically explicit plans now.
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How do we do that if we don't know the geography of biodiversity in the region,
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if it's so unknown to science?
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So what we've been doing is using
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the laser-guided spectroscopy from the CAO
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to map for the first time the biodiversity
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of the Amazon rainforest.
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Here you see actual data showing different species in different colors.
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Reds are one type of species, blues are another,
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and greens are yet another.
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And when we take this together and scale up
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to the regional level,
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we get a completely new geography
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of biodiversity unknown prior to this work.
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This tells us where the big biodiversity changes
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occur from habitat to habitat,
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and that's really important because it tells us
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a lot about where species may migrate to
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and migrate from as the climate shifts.
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And this is the pivotal information that's needed
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by decision makers to develop protected areas
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in the context of their regional development plans.
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And third and final question is,
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how do we manage biodiversity on a planet
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of protected ecosystems?
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The example I started out with about lions hunting,
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that was a study we did
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behind the fence line of a protected area
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in South Africa.
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And the truth is, much of Africa's nature
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is going to persist into the future
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in protected areas like I show in blue on the screen.
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This puts incredible pressure and responsibility
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on park management.
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They need to do and make decisions
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that will benefit all of the species that they're protecting.
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Some of their decisions have really big impacts.
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For example, how much and where
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to use fire as a management tool?
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Or, how to deal with a large species like elephants,
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which may, if their populations get too large,
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have a negative impact on the ecosystem
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and on other species.
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And let me tell you, these types of dynamics
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really play out on the landscape.
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In the foreground is an area with lots of fire
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and lots of elephants:
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wide open savanna in blue, and just a few trees.
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As we cross this fence line, now we're getting
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into an area that has had protection from fire
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and zero elephants:
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dense vegetation, a radically different ecosystem.
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And in a place like Kruger,
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the soaring elephant densities
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are a real problem.
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I know it's a sensitive issue for many of you,
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and there are no easy answers with this.
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But what's good is that the technology we've developed
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and we're working with in South Africa, for example,
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is allowing us to map every single tree in the savanna,
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and then through repeat flights
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we're able to see which trees
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are being pushed over by elephants,
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in the red as you see on the screen, and how much that's happening
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in different types of landscapes in the savanna.
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That's giving park managers
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a very first opportunity to use
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tactical management strategies that are more nuanced
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and don't lead to those extremes that I just showed you.
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So really, the way we're looking
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at protected areas nowadays
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is to think of it as tending to a circle of life,
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where we have fire management,
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elephant management, those impacts on the structure of the ecosystem,
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and then those impacts
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affecting everything from insects
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up to apex predators like lions.
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Going forward, I plan to greatly expand
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the airborne observatory.
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I'm hoping to actually put the technology into orbit
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so we can manage the entire planet
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with technologies like this.
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Until then, you're going to find me flying
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in some remote place that you've never heard of.
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I just want to end by saying that technology is
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absolutely critical to managing our planet,
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but even more important is the understanding
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and wisdom to apply it.
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Thank you.
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(Applause)
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Original video on YouTube.com
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