Caatinga | Biomas do Brasil | Ep.5

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Paulo Jubilut

Você sabe qual é o único Bioma exclusivamente brasileiro? Se pensou em Caatinga, acertou! Encontrad...

Video Transcript:

What's up guys! It's my pleasure to have you back for another videoclass of Professor Jubilut. I want to start this educational process, talking about this wonderful tree, the umbuzeiro tree, which is fundamental to Brazilian northeast.

That's because these trees are capable to store water in their roots. A plant like this can store up to 1500 liters of water in the root. Then of course, it keeps producing leaves, flowers and fruits during the drought season, which makes this species a true oasis here in the northeast.

Besides, many animals come to this plant during the drought season in order to feed off its flowers and fruits. They in turn, help the umbuzeiro to spread its seeds all around. By the way, the umbuzeiro tree is only one of the plants we will study in today's biome, so put some blood in that eye because today there's Caatinga for you.

In order to shoot these videos I left Florianopolis in Santa Catarina and went to Ceara outback. In the natural reservation of Serra das Almas, traveling almost 2240 miles to reach an extremely preserved Caatinga. I don't know why, but whenever I say "Caatinga" I feel like screaming like this "Caatinga, Caatinga!

" "Caatinga, Caatinga is very important, Caatinga is awesome, Caatinga must be preserved". The Caatinga occupies almost 11% of the Brazilian territory. Being found almost throughout the whole northeast and north of Minas Gerais state as well, making border to other three national biomes: The Amazon, the Cerrado and the Atlantic Forest.

The Caatinga is certainly the most wronged biome of Brazil, usually depicted as a poor and barren place, many people believe that there's no biodiversity of plants and animals here. But as you can see behind me, we do have a Caatinga, besides, an interesting detail is that this biome is exclusively Brazilian. "- But Jubijubao, aren't there other semi-arid regions in the world?

" There are others, but the species and animals found here are exclusive of this place. ♫ Before the arrival of the Portuguese, the native Guarani tribe used to live here, they called this place "Caatinga", which means "white forest". That's because when you have a drought period, part of the plants that exist here, lose their leaves, which gives the place a whitish aspect.

"- But Jubijubao, it's all green now! " It's because I'm here during the rain period. As you know, the climate of the Caatinga is semi-arid, so we have almost 9 months of drought and 3 months of rain.

That's what characterizes this climate, a dry and hot place. The average temperature here is around 27 degree Celsius. Now, regarding the rain - because it's what highlights the Caatinga - actually 9 months, 3 months, 9 months of drought and 3 months of rain, it doesn't mean it rains every year.

This is an irregular rain and many times you have 2, 3, 4 years without a rainy period. Usually the year in which we have the El Niño phenomenon, coincides with the year in which we have less rain here in the Caatinga. Now bear in mind that the precipitation rate of this biome, stays around 600 mm or rain per year.

It's Brazil's lowest rate, now another rather interesting detail is that there are regions of the Caatinga, in which you have less than 240 mm of rain per year - that's really low - and in other places such as this one where I am now, you can have up to 1500 mm of rain. Which is basically what happens in the Atlantic Forest. The difference is that the rain is more well distributed throughout the year and here in the Caatinga it's well concentrated in few months.

Now, how can a biome that connects to the Amazon and also the Atlantic Forest receive so little water? There are several processes that make the Caatinga rain to be ill distributed, but the mainly one is the type of rugged landscape where this biome is placed - you can see right behind me, we have valleys, we have flatlands, mountain ridges, mesas, so what happens is that the rain clouds that come from the Atlantic Ocean, end up hitting these higher regions. So what happens?

It will rain more in the region hit by the clouds! The region located ahead of this elevation ends up receiving much less rain. The soils of the Caatinga, vary from region to region, now, the most common soil is this one right here, a rocky soil - it's so rocky in here that's basically a rock and plants still grow on top of it.

Of course, a soil of this type stores very little water. Besides, the plants roots have extreme difficult to be able to penetrate it. Many of them I'm observing here, are superficial roots, it's truly a miracle that you have a vegetal formation in this type of soil, by the way, kudos to the plants, to all of you who are truly warriors because thriving here is inexplicable and of course, this is the type of soil that will allow this vegetal formation that you know in the Caatinga, this more traditional type of thorny and sparse plants, the predominance of cacti, because only these species manage to thrive in this type of soil here.

Here I'm in other region of the Caatinga, and the thing we notice here is that the soil is more arenaceous, so it's really a soil that reminds me of beach sand. This type of soil here, the sediments are not so tied up and the water won't stay retained, so it's not a good soil to store water. "- But how come you have a forest with this arenaceous soil?

" Two characteristics: First off, we have a lot of litterfall that forms humus, which is the forest's fertilizer - as well as the Atlantic Forest humus - there's also humus in this region of the Caatinga, which is decomposing organic matter and there's also a water stream nearby, so this is a soil that naturally has water. Because if depended only on the water rain, certainly there wouldn't be this vegetal formation here, because of this type of arenaceous soil. Quite interesting is that you walk though the Caatinga and suddenly you look at the soil and you are able to notice how it's arenaceous - this is beach sand, as if you had a relatively dense vegetation thriving on the beach sand.

This is the Caatinga soil. Of course, we have a diversity of types of soil in the Caatinga as well as a diversity of types of fertility of these soils, so depending on the region the solo will be more fertile - even more suitable for developing agriculture - and in other regions the solo will be extremely poor of nutrients. "Surviving the Caatinga" moment.

Say you are lost in the Caatinga during the drought season and run out of water - then you will need a little water - the solution is to grab a piece of cactus, such as this xique-xique cactus that I just got. Now I'm going to teach you how to cut the xique-xique cactus open, so you drink the water inside, let's go! First off, you're going to poke one of the tips like a corn cob, and then you cut the other side!

You also need a working knife. Dude, this is how you do, you peel it off like a pineapple. Like a pineapple, you know, the pineapple you have home?

You hold it here, and you put it here, and you start to cut - be careful with the thorns! They are pretty pointy thorns. It's important that you always carry a sharp knife!

You need to remove all the thorns! I just removed the thorns, now I'll cut it open right in the middle and show you how it is - you cut the cactus in the middle then you just squeeze it and the water will fall in your mouth, that's because cactuses have a tissue inside them called aquifer parenchyma, a tissue specialized in storing water. Almost 90% of the cactus weight is water thanks to the presence of this tissue and then of course, it can easily utilize this water during the drought season and if you find one, you just need to squeeze it and you will have a little water to quench your thirst - I hope you are lucky and manage to find a cactus with more water than the one I just grabbed.

And as long as we're talking about cacti, we should mention the curious coroa-de-frade, a small globe-shapped cactus which presents flowers on its upper side. The nectar of these flowers is well appreciated by bats and hummingbirds. Be able to store water is a highly important strategy if you are to survive in an environment that will be without water for at least nine months, with no rain, which is what happens here in the Caatinga.

And cactuses are experts on it. Now, besides having the tissues that store water, you also need strategies to avoid the loss of water for the environment, case in point, when it comes to cactuses here, their leaves are reduced and ended up becoming thorns. Catuses thorns - this one is a xique-xique cactus - are reduced leaves.

When you turn your leaf into a thorn, you firstly reduce the loss of water by transpiration, there are less stomata here, besides, you reduce the contact surface with sun radiation. Surely that's also a strategy so that you won't lose water for the environment. Another interesting detail is that these thorns, also protect the plant against herbivory, besides reducing water loss for the environment, as long as the xique-xique cactus is highly nutritious and has plenty of water, as I showed you, so there are many animals here that would be feasting on these guys, if they had no thorns.

Now, if you weren't lucky enough to have your leaves turned into thorns, another adaptation that gives you advantage in a place with a dry climate, is to have small leaves. When the plant has small leaves, and many species of plants of the Caatinga have small leaves, you diminish the contact surface with sun radiation, therefore you are able to save water. Then you might ask "- But Jubijubao, how do these plants make photosynthesis, if they turn their leaves into thorns?

" Check this out: These cactuses - ok, their leaves are reduced - but if you take a good look, their stalk is green. Why green? Because it's full of chloroplast and you have chlorophyll inside these chloroplasts, the fundamental pigment to make the photosynthesis occur.

That means that in case of plants that reduce their leaves to thorns, the photosynthesis is made in the stalk. The embiratanha is one of these plants that make photosynthesis through the stalk. If you notice, you will see some green parts.

It's able to make this metabolic process exactly in those parts. Another strategy you can adopt here in the Caatinga - in case you're a plant and want to survive in this place - is losing your leaves during the drought season. And many plants here do that, they lose their leaves to do what?

To save water. The less leaf you have, the less water you lose through transpiration. So they not only lose their leaves, they also get into some kind of dormancy phase and they stay this way waiting for the next rain period.

Write it down: Plants that lose their leaves in drought periods are classified as deciduous plants. An interesting detail is that here you are able to observe a plant without leaves and it really obtain a whitish aspect, so imagine all these plants that are still green, becoming exactly this way - you have a whole white aspect of the Caatinga. That's exactly why this biome is called Caatinga, which means "white forest", as I already told you.

Look how cool these pictures! Where we can observe the same places during both the drought season and rain season. Notice how the landscape changes due to the loss of leaves.

Another strategy a leaf can adopt, in order to avoid losing water for the environment, and be able to save its valuable water inside, is to produce a waterproofing substance. Producing a wax, like the case of this species right here, the carnauba. This plant produces so much wax in their leaves in order not to lose water for the environment, that it's got a huge economic relevance for the region - people wait for the leaves to have plenty of wax and collect these leaves to sell the famous carnauba wax.

Guys, I'm amazed by these plants that thrive in such rocky soil, which is even called "slab soil" because indeed it's sort of a slab, and there are plants thriving in here. For instance, check this out, there's rock here and some soil, check this out, arenaceous soil. This plant right here, for instance, it's stuck in between the crevice and put its roots deep inside, it's pretty steady.

Now this one here is quite shallow - I'm going to put it there again later, but just so you can see how shallow its root is, I already pulled it out - there's only this root. That's a strategy to save water. Why?

When water hits here, it won't be stored in the soil, so if you have shallow roots you have a better chance to keep some water here. Another strategy when it comes to roots, is that some species of plants have tuberous roots that not only store nutrients, but water as well. An interesting detail is that the life cycle of these plants is regulated by the rain period.

That means that when they germinate, thrive, produce their flowers, reproduce, produce fruits and seeds in the short interval of the rain season that usually lasts about three months, in other words, the plant does all that in three months and then when the drought season comes, many of these plants will die, but they will leave a great heritage here, which is their seeds. They will stay here, quiet, dormant waiting for the next rain season. As soon as it rains, the seed germinates, thrives, reproduces, produces its fruits and seeds, and leave them here, then the drought season comes and these seeds will wait the next rainy period.

In this moment, while I'm here, it's the end of the rain season. So they are all green and have plenty of flowers - this is an example of a bromeliad inflorescence, so they are reproducing, producing fruits, seeds, because as soon as the drought season come this will entirely change. As you may notice, the Caatinga plants found their way to be able to survive in an environment that lacks water.

These plants here in the Caatinga, are classified as xerophytes - xerophyte plants are the ones that have adaptations to survive environments with little water, which is exactly what happens in this biome. 30% of the plants found here in the Caatinga are endemic due to the fact that they have such specific characteristics, they are only found in the Brazilian semi-arid. Hence the great importance of preserving this place.

♪ Besides the climate and soil, as I already said, the landscape has fundamental importance when it comes to rain distribution in the Caatinga - there are places with more rain and places with less rain. This will have direct influence on the landscapes we found in the Caatinga. Forest formations where there's more rain, sparse vegetation with predominance of cacti where there's less rain.

So the Caatinga is not homogeneous, its landscape is different when it comes to vegetation. That's why some authors like to call the Caatinga a "Caatinga Domain" because actually it's not a single biome, it's several biomes - as if we had several Caatingas each one different from the other, of course influenced by the amount of rain received by each one. So calling the Caatinga a biome is not wrong, but if you want to stand out from the crowd, you may call it "Caatinga Domain".

Here there's another type of Caatinga known as "executioner", exactly because the main characteristic of this vegetation, is this entanglement of plants with thin stalk, so it's extremely difficult to get inside, you have a lot of thorny plants, in other words, you are going to get hurt. So this vegetation works like some kind of executioner, torturing you in case you try to get inside. Besides, if you are running away from the police that's a good place to hide because few people have a spine to get in here.

Of course, I'm talking about this because Lampiao loved hiding in this type of Caatinga. "Executioner", because he knew the police would have a very hard time to get inside this type of Caatinga. ♫ Now guys, one thing you may quickly notice - which is quite a strong characteristic of plants here in the Caatinga, is that they have plenty of thorns, is hard to find any vegetal species here that doesn't have thorns, besides, I just got a bunch of them stuck in my hand!

This herbaceous plant here, these thorns are extremely small, so when I picked one to pull it out because I wanted to film this part here, I basically got dozens of thorns stuck in my hands, so walking throughout the Caatinga means to have thorns in your body. Here we have another type of landscape, which is the arboreous Caatinga that has predominance of arboreous plants, which are trees that can reach up to 65 feet such as this rosewood beside me. Of course this region allows this forest formation because the soil has better quality, has more nutrients, there's a larger volume of water, probably the soil has the characteristics that allow the storage of more water, and all these things will give the conditions for these plants to be able to thrive and form a truly forest in the Brazilian semi-arid, and obviously you have a huge biodiversity here, besides, the native Tupi tribe used to live in the arboreous Caatinga.

Now we have a rather interesting detail, we have two plants of the same species thriving on top of this rock, they are known as "gameleiras" and if you notice the roots of these two trees are connected in this part, this is great because several studies are finding that plants, specially trees, like to communicate to each other through their roots, so they really bind their roots to communicate, to talk to each other, of course, in plant language, and they also trade nutrients with each other, through this connection between their roots. Of course, it's highly important that you are capable to exchange some nutrients with your neighbor, in a place that lacks water, such as the Caatinga ♪ Here we have another type of landscape formed by shrubs, "- Ah, what are shrubs? " They are these plants right here, which are 6 to 16 feet tall, a vegetation a bit more sparse, and this region here, this landscape is known as Shrubby Caatinga, exactly because of the predominance of plants known as shrubs.

♫ Another interesting detail is that around 950 vegetal species are found here in the Caatinga. It's not a diversity that high. That's because as I already said during this videoclass, this is a peculiar place, not every plant here is able to thrive without trouble, you need to have a series of adaptations to thrive in such an inhospitable environment.

Now, about 350 species out of 950, are endemic, in other words, almost 1/3 of Caatinga plants are only found here, plants that will provide for a huge amount of animals in the Caatinga, with their leaves, flowers and fruits. A high animal biodiversity, as opposed to plants biodiversity. We will be addressing these animals in the next video about the Caatinga.

All in all, needless to say it was a treat to be here with you, a big hug, bye! Subs: msfreelancer http://tinyurl.