Invasive Species !!!! by Dr. Scott

Whether brought into the Iguassu Park in the back of Jeeps powered by biofuels such as sugar cane ethanol - (like our scientifically-minded companions Mary Ann, Marissa Morgan and Maddie) or in the guts of toucans - who dispose of digested seeds and other fruits as they travel from one place to another by air, (see gory details and effects of this incident later...), Iguassu is a haven to a wide range of biodiversity in the form of plants and animals...

Trails in Iguassu park cover a range of altitudes and vegetation types.

Some of these plants are true marvels of form, function and color, such as this beautiful green and yellow bamboo plant easily to be seen along the trails. Bamboos come in hundreds of species and are appreciated world-wide not only for their decorative potential in landscaping but also as true building materials in housing. They can also be attached to form scaffolding structure used in construction work, something commonly seen in China. They grow very fast and are a good source of celulose. Some varieties are planted for use in baby diapers.


Ferns can be seen along the park trails.

This special clover-like species thrives in dark, wet corners, over rocks, where other species are unable to adapt...Not only do they thrive on acid soils, but have in their leaves calcium oxalate crystals which make them unpalatable and tough to digest... a sure way to deter those herbivores!

The park's trails are well marked and have important plant species signaled with their common name such as this Guava-related tree the Uvaia, as well as with its ' Linnaean' scientific name (see binomial nomenclature) usually involving roots of words in Latin or/and Greek, which in someway describe the species... It is fun trying to guess details about the species, just reading its name which in many cases will describe color, size, chape or some other peculiarity about the individual.
Among the several exotic species in the park are ferns. Ferns are very 'happy' in humid, shady environments, such as along the parks trails on the forest floor, and many times indicate soils conditions. They are resistant to acid soils containing high levels of aluminium, toxic to most other plants...! Could we use this and other traits shown above to improve our crops through genetic manipulation?

Symbiosis
Even where there is practically not much in the way of nutrients available from the soil, such as over rock surfaces, the high air humidity allows for lichens (a symbiotic association of algae and fungi) to proliferate over large surfaces, successfully competing with ferns and mosses. Lichens will eventually erode rock surfaces obtaining a few nutrients.

Zebrina, a very common decorative household potted plant, is to be found everywhere along the park trails... An African species, specially well adapted to the local tropical rainforest conditions prevalent in Iguassu. Park rangers and erradication squads are continually harvesting Zebrina and other exotic plants from the park area in order to keep ecological balance in check... The local species of wild pigs, are actually quite happy to feed on it!

These little yellow rods are the beginnings of a wild 'black pepper' fruit. The plant is a very important food source for many species of seed eating birds.


We have enjoyed exploring and discovering these diverse life forms and we hope that you have learned something new along with us!