Saturday, 6 February 2010

Bromeliads

Bromeliads are one of the characteristic plants of Mata Atlantica region. As a type they normally have thick fleshy leaves growing from a central rosette, and range from tiny epiphytes sitting on branches in the forest to huge individual plants sitting on sandy ground of the coastal strip.

The problem with being a bromeliad is that you are stuck at ground level, and other plants can grow tall and shade you. However, there's also lots of advantages. They share with orchids and cacti a special metabolism based on crassulacean acid, which means that they can "breathe" at night, drastically reducing water loss. Many also form a water tank by joining their leaves together, sometimes with over a litre of water. This means that they can evolve into epiphytes, which cling to high tree branches getting all their nutrients from the air and detritus on the branch around them, but close to the sun (thus redefining "ground"). Or lipophytes, which sit on bare rock free from competitors for sunlight, such as those found growing in cracks in the otherwise smooth rocky hills of Vitoria and Corcovado in Rio.

It has been estimated that up to 50,000 litres per hectare can be held in bromeliad tanks, and although the normal quantity is much, much, smaller, it is a permanent enough habitat to form an attractive option for small creatures in need of a home. Dragonfly larvae can be fund there, and even the tadpoles of many frogs such as the Brazilian Hylid frog found in Espirito Santo. There are spiders that live exclusively in the MA bromeliads, and at least 43 species of ants (there really are an awful lots of ants in Brazil).


More importantly, from a human perspective, they are a significant habitat for the Aedes mosquito, carrier of Dengue fever. Not only do larvae wiggle in the forest bromeliads of the Mata Atlantica, dreaming of the cities they will invade when they are grown up, but Aedes have been found in the large bromeliads found on the rocky mountain outcrops of Vitoria. Especially the Alcantarea genus which forms 90% of the bromeliad flora there. Aedes seem not to like bromeliads very much, and prefer to lay their eggs in shaded artifiical containers, but they are there.


Lastly, if you really want to see a bromeliad up close, buy a pineapple. Cut off the top and replant it, with luck it should grow. My grandmother did this on her kitchen window, and it is still common practice in small farms and households here.

6 comments:

Anonymous said...

Such a nice write up!

An enzyme called bromolein is extracted from pineapple and is now sold at health food stores for aiding digestion. Also supposed to be effective in inhibiting inflammation of the joints. Wonder whether these bromeliads in Brazil can be commercilaly exploited.


I was also interested to know their role as habitats for different animals. Common knowledge in S.India is that pineapple bushes are a favourite haunt for poisonous reptiles.

'Crassulacean acid'- any known properties?

Different note, is dengue a big concern in Brazil?

sann2282 said...

We have Bromeliads here in Kerala, but I think these may not be native (I can be wrong though!).

Macaco verde said...

Thank you for your kind comments! I didn't know about the poisonous reptiles, that must make harvesting rather a tense experience!

Bromolein seems to have quite a few medicinal effects. It's apparently an anti-inflammatory, and reduces unwanted blood clotting. Its is also an extremely efficient protease which makes it a good meat tenderiser, but problematic as a medicine! It is concentrated in the plant stem, which is a waste product of the pineapple industry, and I know there is quite a lot of research into uses for this and other potentially useful compounds. There's also interest in how other bromeliads have been used historically in Brazil, and in Mexico and other countries, not only to find new drugs, but also new crops which would grow well in arid conditions.

Dengue is certainly a serious concern here. The town of Vila Velha, for example, has had about 11,000 cases since 2001 and I know personally several people who have been infected. The authorities take it very seriously, there are regular fumigations and lots of health education.

Macaco verde said...

Bromeliads are apparently native to the Americas, with one species in West Africa. But the Portuguese were very industrious in tranferring species around the world, there's plenty of south Indian species flourishing in Brazil.

Alex Alen said...

This is so essential post. This information helps them who are new gardeners.
Thanks for helpful post for us.
Bromeliads

Alex Alen said...

This is so essential post. This information helps them who are new gardeners.
Thanks for helpful post for us.
Bromeliads