Rainforest Research- Biosphere 2 Facebook Live October 18, 2018

Rainforest Research- Biosphere 2 Facebook Live October 18, 2018


Hello, and welcome Live to Facebook. Biosphere 2 Facebook Live. My name is Joost VanHaren, and I’m an assistant research
professor here at Biosphere 2, and I’m right here in the middle of our Rainforest, which is a 0.2 hectare or it’s about 200 by 200 feet Rainforest that
actually encloses a lot of different plants from tropical forests around the
world. Like I said, it’s enclosing. There is a big, and you can’t see that in this shot,
but there is glass and steel frame that’s enclosing this Rainforest, and
that gives us scientists a very big advantage in a way that we actually can do
things in this Rainforest that are very difficult to do in the real world. And so
that’s why we learned this Rainforest to help us understand better- what might happen to the rainforests on the planet in the future? Now, you might wonder, why would we care about this? Why would we worry about tropical forests? I mean, I live in the United States, and Biosphere 2 is in Arizona. It’s a desert, why would we care about that? One of the key things about tropical forests is that they’re actually the most active biomes
that we have on the planet. So these ecosystems, they cycle nutrients, carbon,
oxygen, and other gases very fast rapidly through their system. And as such, they
have a very strong influence on the globe as well as a whole, and there are
some modelers from both the University of Arizona and other universities as
well, that actually have done some modeling experiments where they cut out
the whole rainforest in the Amazon Basin, and what that would do to their
global climate and it would affect the climate here in Arizona as well as in
other places around the globe. So the rainforest besides for climate they’re
vitally important for all kinds of reasons: medications and so forth, but
that’s not what I’m gonna talk about right now. Today, I’m gonna focus really
about climate change because that’s what I do here and that’s what most of our
research experiments have focused on in the past.
And so what do we look at with climate change? So the main things that
we know are gonna impact the tropical forests in the near future are
temperature, so increasing the temperature and that temperature
increase is partly driven by an increase in carbon dioxide, so how is that going
to impact the tropical forests and then lastly, because of that interaction
between temperature global interactions and so forth, also drought is greatly
impacted. So actually the amount of rain that’s gonna happen in the tropics is
gonna change very much in the future. How we don’t really
perfectly understand but we know that our change is going to happen, so we want
to get a heads-up and get started on that work, and that’s what we can do
here at Biosphere 2, because there’s no place on earth where you can say, “Okay,
we’re not gonna rain on this forest for a month, two months, three months. Here at
Biosphere 2, we actually have that capability to shut off the rain and have
no water, at least from above, come into the forest and then see how they change
the cycling of water. And we found some very interesting things. So one is that
tropical forests are very actually quite resilient to drought. These trees have
undergone a drought that was two and a half months, so 78 days of no rainfall
whatsoever, and they did fine. We saw a little bit of stress here and there, but
nothing that you would say they were really doing badly. Another thing is that
different trees respond very differently. So there’s certain trees that
immediately will shut down and drop their bottom leaves as soon as the
drought starts. So that seems to be a signal that comes from the surface roots
that see a drying out of the soil and then they immediately respond to that.
Other trees they slowly over time, what they do is they close the pores at the
top of the trees in their leaves, and their pores are called stomata.
That’s where they take normally in the carbon dioxide in, but also that’s where
the trees lose their water. So the water that they bring up from the soil, goes
all the way through the stem up to the top of the tree through the leaves and then
out into the atmosphere. So the drier, the less rain there is, the drier the
atmosphere becomes, the more water the trees will lose. And so what we found is
that certain trees will start to close those pores, those stomata, to keep the water
in more and so that they don’t lose as much water. Other trees, they just behave
like nothing has happened. Even after two and a half months or 78 days of no rain,
these trees just behave like, “Well it’s, I got water, I’m fine.” So if you’re dialing
in right now, my name is Joost VanHaren. We are in Biosphere 2 Rainforest, and I’m
talking about what we learn here about how tropical forests respond to
climate change, and what kind of an unique experiments can we do here at Biosphere 2 that you cannot do anywhere else.
So another thing that we can do uniquely here at Biosphere 2, is we can change the
amount of carbon dioxide that is in the atmosphere. It’s a small amount of
atmosphere relative to the amount of the plants that are in here, so the amount of
biology. So whatever the biology does, it is much stronger reflected in the
atmosphere, but it also gives us a chance to change that atmosphere much more
rapidly. And for instance, one example of that is that here you’re in a sunny
afternoon, especially in the summertime, you walk into this Rainforest, and if
you come and visit you should open up your nose. The first thing you do is you
use your nose as your first sense coming into this Rainforest because you will
actually smell this sweet metallic smell, which is a gas called isoprene, and trees
use this to actually reduce the amount of temperature stress they have in their
leaves. Now, what does that tell us about that this is a small atmosphere to the
mother biology? We only smell this really at very high concentrations-
concentrations that are well above what the normal atmosphere has. So you would
never smell this anywhere on earth, but here at Biosphere 2 because of the small
amount of atmosphere relative to the amount of biology. You can smell it. So
what we’ve done with experiments is to actually change the
carbon dioxide concentration, and for periods, short for turn periods, for three
days on end, we changed the concentration to different levels. Ones that we’ve had
twenty-thirty years ago, all the way up to what we expect in about a 100-150
years from now. And what we see is that this Rainforest will take up more carbon
dioxide as the carbon dioxide concentration increases, and that’s no
surprise. Carbon dioxide is plant food, and so with
that you give it more food, the trees will grow more. However, beyond a certain
level, which is we are expected right now to reach around about 75 to 80 years
from now, they don’t need more carbon dioxide. So what is happening then is
that they would need other nutrients. So this suggests that there is a
limitation of time that the plants, the forest ecosystems, will help with
taking up carbon dioxide out of the atmosphere through their photosynthesis.
So lastly, I want to come back a little bit to this temperature aspect, because
Biosphere 2 is a greenhouse, and the greenhouse- What does it do? It actually
heats up, and so we have elaborate cooling systems to cool down, and if you
would do a behind-the-scenes tour here, you would actually go down in the belly,
you would see that kind of apparatus that keeps the biology alive
here. But one of the key things is that what we found is that the whole
population seems to shift. So there seems to be an effect, temperatures of
pressure on the plants, that certain plants can survive higher temperatures
while other plants can’t. And lo and behold, and coming back to that
gas isoprene, it’s actually a lot of the plants that emit that gas isoprene, that
are able to survive under these conditions. Another thing is that we
found is that the plants can very rapidly adapt to higher temperatures and
so if you think about it, normally a tree grows up through the canopy and
then becomes like a top of the canopy species. Well, in that rise, in that growth
of the tree to higher levels in the canopy, they’re gonna see
less shade, they’re gonna have also see higher temperatures as well. So trees in
the real world have to be able to adapt to, but what we’ve seen here at Biosphere
2, because we have seasonal cycles and so forth, that literally leaves can
change over a period of time of on the order of three to six months. And so
they very rapidly can respond to that That, the other thing is that temperature,
they can photosynthesize, so they can take up carbon dioxide at much higher
temperatures then the models thought that people had developed for the real
world. So that has changed our way of thinking a little bit about how do we
include photosynthesis in the way that we make predictions about the tropical
forest responses to climate change. So those are a couple of the main things
that we have been working on here at Biosphere 2, and for instance next
Saturday, there is I will give a behind-the-scenes tour. So anybody who is
interested in, has questions for me beyond what you can ask here potentially
on Facebook Live, I’m more than willing to answer those to you at that point in
time. Should we answer right now a question if there is one? Susan asks, “With the closed environment at Biosphere 2, does that alter the findings compared to being in an open environment, and can you compensate for that somehow?” So, Susan had a great question. She asked
whether being enclosed in Biosphere 2, whether that’s gonna change the results, and how do we compensate for that. Fantastic question, Susan and you’re
right on it and in science experimentation, we always have to be
very cognizant of these kind of issues. What does the experimentation, how does
that affect how we find things? So the way that we see for instance
there some effects, one is that the trees are limited in their growth, where
they can go. The trees, the way that they build strength, because we don’t
have wind that normally they would have in the real world. So there’s a couple of
things that are going on that are affecting it. There is no UV light so
how that impacts the chemistry in the leaves, those are the kind of things
where there can be some changes. And so we’re very aware of that and so
therefore, what we find here we don’t say then directly, “Okay, this is how
tropical forests behave and respond to that.” We use an intermediary
through the model, so Biosphere 2 itself is a model system, and we only
really use it to inform the model systems that we use to make predictions
in the future. That’s one, the other thing is as a way of a magnifying glass.
Because there’s so little amount of atmosphere relative to the amount of
biology, the response of the biology to the atmosphere is so much faster. So we
can use Biosphere 2 as a magnifying glass to look for certain things, look
for certain responses, and then go to the real world, and then see, can we find
those as well in the real world? So our adaption is in short, we don’t
directly what we find at Biosphere 2 and say, “This is how it’s happening in
the Amazon basin.” Now, we use an intermediary and a filter, sort of as a
model one and two as using Biosphere 2 as a testing ground, fleshing out
ideas and then really see how that happens in the real world. Cool, right, thank you very much.
See you all hopefully soon at Biosphere 2.

Posts created 41237

Leave a Reply

Your email address will not be published. Required fields are marked *

Related Posts

Begin typing your search term above and press enter to search. Press ESC to cancel.

Back To Top