Note: Where available, the PDF/Word icon below is provided to view the complete and fully formatted document
Disclaimer: The Parliamentary Library does not warrant or accept liability for the accuracy or usefulness of the transcripts. These are copied directly from the broadcaster's website.
Malaysian and Indonesian peat swamps drained -

View in ParlViewView other Segments

Robyn Williams: Peat is often associated with swamps, especially in our region. Catherine Yule from
Monash University has been braving them in Malaysia, and doing good science but finding bad news.

Catherine Yule: Most of the world's tropical peat lands are in the Indo Malayan region, and these
are forests with trees that can be up to 70 metres tall, although there's not too many of those
ones left, they've mostly been logged, and they grow on this soft spongy bed of peat which can be
up to 20 metres deep. Sometimes it's only a few metres, it depends on how old the peat is and the
circumstances of its development. But it's like this spongy bed where if you're walking you can all
of a sudden go in up to your armpits in this spongy wet mass because the whole of the base of the
peat swamp is waterlogged, and during the wet season it will come up above the level of the base of
the forest. So it can be even half a metre or even a metre above the forest floor, just water.

So these trees have to be able to cope with living in a totally waterlogged environment, plus it's
very, very acid. The acidity gets down...like vinegar actually, pH of 2.6 even, typically pH 3. So
very, very acid, it's very waterlogged, very low in nutrients, very low in oxygen, it's this
extreme environment and yet we have up to 240 species of trees in a hectare, so it's very diverse.
It's just this amazing place where you have orang-utans and tigers and rhinoceros...not that you
ever see them but you know that they're there.

Robyn Williams: And where did the peat come from in the first place?

Catherine Yule: This is one thing that I'm really trying to uncover exactly what happens. Basically
when the leaves drop they're not decomposing. So if you walk into any normal tropical forest,
tropical soils tend to be very, very poor, they'll be this yellow clay, what we call laterite
soils, and they'll have this thin layer of leaf litter on top that cycles incredibly fast. There
will be a centimetre maximum thickness of leaf litter that's just breaking down, breaking down and
recycling, sending the nutrients back up into the trees. So everything is happening really, really
fast, and it's one reason why tropical forests work.

But here we have a system where instead of the leaves breaking down they're just building up into
peat. They sit there and sit there for...typically the peat swamps are about 5,000 years old max,
since the last Holocene incursion. And so the leaves just slowly disintegrate without actually
decomposing, and gradually build up. If you dig down into the peat, as I've been wont to do, as you
go down deeper the particles are finer, but it's just these dark brown fine particles...and then
when a leaf first falls in a peat swamp all that happens is the cellular contents leach out leaving
the structure of the leaf behind. So instead of fungi and bacteria breaking the whole leaf down it
just leaves an entire leaf.

Robyn Williams: I'm amazed that some small animals can actually live there in such an acid
environment.

Catherine Yule: I was amazed too. My main interest is actually invertebrates. I did my PhD on
invertebrates on Bougainville Island, and I'm interested in fresh water invertebrates and that's
what first brought me to the peat swamp. My students and I, we've found nearly 100 species just in
the forest that we've looked at.

Robyn Williams: What sort of creatures?

Catherine Yule: A lot of chironomids, which are midge larvae, lots and lots of them. Lots of mayfly
larvae, caddisflies, dragonflies, water bugs, lots of little cladocerans, little crustaceans, some
worms, quite a few different things, a lot of air breathers and a lot of things with haemoglobin in
them because the oxygen levels are low. There are a lot of things that are missing. You won't find
things like molluscs because low pH interferes with the calcium metabolism. You won't find too many
crabs and prawns for similar reasons, but a lot of fish. Just one degraded forest we've been
looking at there's nearly 50 species of fish. In fact in all the local peat swamps a friend of mine
has found nearly 300 species of fish. So it's very diverse actually. People just haven't looked and
one reason is because they're difficult to go into. There are a lot of ants and you get stung a
lot, and the plants tend to be very heavily protected in order to conserve their nutrients, so they
have thorns and prickles and I always come out covered in blood. That's just part of the
excitement.

Robyn Williams: That's what you're studying. What concerns you about the way these peat swamps are
being exploited in Malaysia and elsewhere?

Catherine Yule: There's a lot of valuable timber, there's a tree called Ramin which is very
valuable, so initially they were exploited for the timber and people thought of them as really
wastelands. They weren't interested in them. People can't just walk through them easily, they're a
little bit scary, I guess. So originally it was timber, but then they started clearing them for
agriculture, and more than 60% of them are now being cleared for oil palm, and that's really the
major problem, and in particular with this rush towards biofuels, the Europeans and other people
wanting biofuels, they're getting this oil palm. The other thing of course is palm oil is used in
fast foods, and so a lot of palm oil, I believe, is going to America for their fast foods. It's one
reason why the Americans are getting fat.

Robyn Williams: Really? I would have thought that if you clear peat swamps, the first thing that
would happen is an awful lot of CO2 and methane would be released.

Catherine Yule: That's exactly right. What they do first is they drain it, and this is really bad
for any peat swamp because they function with this rise and fall of the water, and all the animals
in them, it's all part and parcel of the way the ecosystem functions, so if you drain it, it's a
bad thing. So they drain it and it becomes susceptible to fire then of course because once that top
layer is dry, peat is used as a fuel, it's wonderful fuel and it burns very readily. So they drain
it, then they log it, and the peat then starts to disintegrate, starts to compact. So where you had
this big, thick spongy layer, within a year or two it's lost a metre in depth and then it just
gradually shrinks down and very readily burns.

But it's actually very low in nutrients, so it's not very good agricultural land at all. In fact,
in Indonesia they cleared a million hectares...this was Suharto who cleared a million hectares for
his Mega Rice project, put huge canals through it, cleared the whole area. And you might remember a
few years ago when there was a lot of really horrible fighting between the local people and the
Javanese who had been brought in, the transmigrants, to plant rice, and the Dayaks eventually just
started attacking the Javanese because they'd destroyed their whole forest and left them with
nothing.

The Mega Rice project failed completely, they couldn't grow rice on this land. So there's this
one-million hectares of cleared land that is just...it burns every year, every dry season it burns,
so now they're trying to rehabilitate it. The local people are trying to build dams, block the
canals, flood it again and try to reforest it again. But it's really difficult because everything
has been so degraded.

Robyn Williams: And the position of the government? Are they helping? Are they on side?

Catherine Yule: Well, the government wants the revenue from the oil palm, all the governments do;
the Indonesian, the Malaysian; and the revenue from the logs. They don't see that these forests
have a value far beyond this short-term gain from the palm oil.

Robyn Williams: How much does that worry you, what's going on? Is it a really big problem or not?

Catherine Yule: It breaks my heart, I'm absolutely terrified of what's happening. During the '97,
'98 El Nino event, there was carbon dioxide emissions that were equivalent to about 40% of the
annual emissions from fossil fuel combustion. There was this global peak in carbon dioxide
emissions that they measured and it was from the burning of the peat swamps in Indonesia and
Malaysia, particularly in Borneo. So it's certainly a huge addition to global warming. And then the
effects on hydrology...when you clear the peat swamps and start draining them you affect flooding
of all the lands around because normally these peat swamps are a huge store of water, and once
they're gone these tropical rains just end up flooding around about.

And the biodiversity loss, of course. One of the major remnant populations of orang-utans is
actually in a peat swamp forest in Indonesia that's not protected, not protected at all, and very,
very little of the peat swamp forests are protected; I think it's something like maximum 0.3% of
the lands are properly protected. Because even in peninsula of Malaysia there's one 100-hectare
forest that's virgin forest that's protected forever, but 100 hectares is nothing. It's drained all
around which means it's degrading because of the drains around it. The last major beautiful forest
in south-east Pahang, it's scheduled for logging, albeit selective logging, but any logging is bad
for a peat swamp, they're just such a fragile ecosystem.

Robyn Williams: Is the world aware of what's going on?

Catherine Yule: I don't think so, that's what really worries me. People think 'we've got to go into
biofuels, there's oil palm, great, let's use this'. I don't think they really understand. But
certainly some things are starting to change. One of my students was working with Sime Darby which
is the largest oil palm producer in the world, and she was an environmental manager there, and she
said that it was starting to be that companies were starting to refuse to buy palm oil that had
come from peat lands. So Sime Darby were looking to convert their oil palms on peat back to peat
lands. So that was fantastic, and I'm really hoping that that will happen, but it's so difficult to
do. Once the peat lands have been degraded it's very hard to rehabilitate them.

Robyn Williams: Yes the words 'peat swamp' would not necessarily conjure images, whereas 'tropical
rainforest' might.

Catherine Yule: Well, they are a tropical rainforest and they're one of the most beautiful of the
tropical rainforests, they're just fantastic. If people could see...it's hard to photograph them
properly because when you're in there you've got these huge trees, 70 metres tall...that's a big
tree, with great buttresses and amazing stilt roots and hoop roots and really exciting stuff, but
it's hard to get a vista to show what they look like. It's hard to step far enough back from these
big trees to take their photograph, you know!

Robyn Williams: You mentioned that you were in Bougainville before, in Papua New Guinea, how much
does the similar problem affect them?

Catherine Yule: I think very much so, especially West Papua where the Indonesian government doesn't
care so much about the Papuans. I think they're taking away their lands willy-nilly, and the West
Papuans don't have much of a voice. I think it's very bad there. And I think Papua New Guinea
too...I know Malaysian companies are in Papua New Guinea.

Robyn Williams: So much for the problem. What about your research, where next?

Catherine Yule: Well, what my students and I...we're trying to find out how they function actually,
just exactly what's going on. Originally we went in there and I was wondering 'what are the animals
eating?' because normally fresh water invertebrates would be eating leaf litter or they'll be
eating algae or phytoplankton, something like that. The leaf litter is not breaking down so they
can't be eating that, the water is really brown, it's what we call 'black water' so there's not
much algae and the forest is so thick, you just don't have the light for a lot of algal growths, so
they weren't eating algae. So I was curious to find out what on earth they were eating.

Originally I thought it might be forest fruits or something like that, so we did a lot of studies
and we found in fact that the basis of the food web was bacteria, and this is unusual because
everyone had been saying these forests are so extreme that we don't have microbial decomposition,
the microbes can't survive in the low pH, low nutrients and everything. So when we found that the
animals had bacteria in their guts, we thought, oh, this is something different. So then we've done
stable isotope studies and genetic studies looking at the DNA of the microbial communities as you
go down deep into the peat swamp.

I've had people all over the world actually helping me, in America, Germany, England and so forth,
and what we've found is in fact that, yes, bacteria are really important in the peat swamp but not
in the normal way where you have leaf litter breaking down and normal decomposition pathways.
What's happening, we believe, is that when the leaves fall, the cellular contents leach out and in
those cellular contents we have what we call dissolved organic carbons, and that's what the
bacteria are using, they're using these organic carbons, eating that, so to speak, and then the
animals are eating these bacteria. So bacteria are in fact crucial to the functioning, but not in
the normal way of most forests.

Robyn Williams: Who'd have thought.

Catherine Yule: Who'd have thought!

Robyn Williams: Giant trees and tiny microbes, linked for life. Catherine Yule is a senior lecturer
at Monash's Malaysian campus in Kuala Lumpur. You may recall the headlines in The Australian
newspaper a few weeks ago saying 'PNG forests all but gone in 13 years'. All for palm oil.