This document compares the Yunque Rainforest and Guanica Dry Forest biomes in Puerto Rico. The Yunque Rainforest receives 200-400 cm of annual precipitation and supports a diversity of broadleaf trees, epiphytes, and 200+ plant species. The Guanica Dry Forest receives 150-200 cm annually with a long dry season, and its plants like button mangroves and acacias have adaptations like thorns and reduced leaves to resist water loss. Methodologies conducted in each forest examined soil properties, temperature, and vegetation differences driven by their distinct climates.

1. Comparison between the Yunque Rainforest and the Guanica Dry Forest
On this report we are going to talk about two major biomes. A biome is a major
life zone characterized by vegetation type or by physical environment. Factors as
mean temperature and precipitation play a major role in determining where biomes
exist. Each biome is also characterized by microorganisms, fungi, and animals
adapted to that particular environment. Vertical layering is an important feature of
terrestrial biomes, and the shapes and sizes of plants largely define that layering. The
species composition of each kind of biome varies from one location to another.
Biomes are dynamic, and disturbance rather than stability tends to be the rule.
The two major biomes that we are going to work on are the Tropical rain forest
and the tropical dry forest. Tropical rain forests across the world are very diverse and
their precipitation is relatively constant, about 200-400 cm annually. Among its plants
it includes emergent trees that grow above a closed canopy. Broadleaf evergreen trees
are dominant in tropical rain forests as are epiphytes such as bromeliads and orchids.
Tropical dry forests precipitation is highly seasonal, about 150-200 cm annually, with
a six to seven month dry season. Many tropical dry forest trees drop their leaves
during the dry season. Thorny shrubs and succulent plants are common in type of
forest.
The Tropical Rain Forest, el Yunque
El Yunque national Rain Forest is a reserve located on the eastern side of the
island and has over 200 different species of plant and over 120 species of animals.
For a forest to be categorized as a tropical rain forests it must have principally two
environmental factors: the location should be on the tropical equatorial zone and the
quantity of rain that it receives a year that it should be 4 to 8 meters.
In the national rain forest el Yunque they are 240 species that been seen and which
26 are endemic and only found in el Yunque. In addiction they have been reports of
47 species that have been introduced, 88 species of wear trees, 50 species of natives’
orchids and 150 species of ferns. The characteristic of the forest may vary from
elevation. The national rain forest is divided on four types of forest which are: the

2. “tabonuco” forest, red tree forest, sierra palm forest and the cloud forest or dwarf
forest.
The plants that we found on the rain forest were:
• Cadan Tree: Produces a fruit the size of a soursop, has a relationship with
mycorrhizae to grow.
• Yagrumo: Cecropia peltata. It is dioecious, meaning it has male and female
flowers on different trees of the same species. The flowers of the female are
tiny and are grouped in inflorescences up to 4 inches long, The male flowers
are much thinner. The female flowers produce thousands of fruits that are
eaten by birds and bats. This keeps flowering and fruiting throughout the year.
This species grows rapidly and their roots are shallow.
• Magohaby (Caboa): Is a valuable wood, light and attractive. Does not have
moth. Mahogany has a generally straight grain and it has a reddish-brown
color, which darkens over time, and displays a reddish sheen when polished. It
has excellent workability and is very durable. It can be Cuban mahogaby or
Dominican mahogaby, although the Dominican magohaby has smaller leafs.
• Bamboo: Grass, stem free of branches, it doesn’t have growth under its
branches. Bamboos are some of the fastest growing plants in the world and
depend on local soil and climatic conditions.
• Guava tree: It was used in coffee plantations for shadow and produces a very
sweet fruit. The spread of the guavas is because the animals will eat the fruit
and disperse the seeds in their droppings The ants that live in this tree are
called “abayarde”.
• Guaraguao Tree: Guarea guara. It is made of light wood like mahogany.
• Tree Fern (Helecho arbóreo): Cibotium spp. They are very primitive plants,
lively ferns and often in danger of extinction in the regions of origin.
The plants and trees that live on El Yunque have big leaves, long and strong roots and
tall stems.

3. Methodology
The objective of The Yunque Rain Forest visit was to take soil samples to see if we
could find phages.
1. Take the soil sample
2. Coordinates
3. Wind Velocity
4. Soil Temperature
5. Ph
Results from el Yunque:
Altitude Coordinates Humidity PH Temp. Wind Muestra? Who?
Velocity
706 18 ̊ 20.298'N 73% 5 80 ̊F Yes NCC
065 ̊45.732'W
2,483 18 ̊18.1989'N 84% 6 73F Yes LBR
065 ̊
47.394'W
56 18 ̊ 21.985'N 80% 5.5 80F 206F/M No
065 ̊46.225'W
2,622 18 ̊298'N 75% 4.2 71F Yes LAPS
065 ̊47.394'W
1,605 18 ̊18.65'N 80% 4.5 78F Yes CMM
065 ̊46.227'W
3,425 18 ̊18.633'N 78% 5.5 73F Yes LRV
065 ̊47.546'W
2,153 18 ̊18.136'N 80% 5 72F Yes YCR
065 ̊47.047'W
The Tropical Dry Forest, Guánica Dry Forest
Flora in this area is limited due to its climate. In this area dry soils are relatively
unproductive because plants need sufficient quantities of liquid to live. This plant
need to go to some adaptations due to the extremely dry climate. Rain comes
infrequently but when it comes the vegetation is transformed. Many plants have

4. highly reduced leaves that resist excessive water loss. Other adaptation is the Cam
(caarssulacean acid metabolism) in which the plant takes CO2 at night and the
stomata remain close in the day. (Campbell biology) The most common one are the
button mangrove, “uva de playa”, Acacia, Melocatus and Agave.
Plants in Guánica:
●Button mangrove: it’s an introduce plant, located far away from the cost. These
plants extract salts from soli. This inhibits the plant growth creating a hypertonic
solution.
●Uva de playa: scientific name coccoloba. It’s an introduced tree, are located close to
the cost.
●Acacia: plant native from Puerto Rico, this plants contain thorns that protect them
from predators.
●Melocactus: native from Puerto Rico
●Agave: live close to limestone, product of ph of rain (5.5 acidic).
Thorns: In this forest the plant have a commonly adaptation which are the thorns.
The thorns are a transformation that has different purposes. The purposes of the
thorns are:
1. Reduce the transpiration of the leaves, which prevent the tree from drying.
2. The photosynthesis is develop on the shaft
3. Prevent that some predators eat the plant.
4. Obligate
the
animal
to
eat
the
fruit
which
benefits
the
dispersion
of
the
plant
Results from Guánica:
Quadrants Group 1

5. Line Transects Group 1
Quadrants Group 2

6. Line Transept Group 2
Quadrants Group 3

7. Line Transept Group 3
Conclusion

8. The methodologies that we used on both ecosystems helped us understand some
differences between them. The Yunque soil is more moist and cooler than the
Guánica Dry Forest which soil was mostly dry and arid. The Guánica’s results
showed how rocks were an important part of this forest. Rocks make a barrier against
fire to protect the forest. The barriers of rocks helps protect the plants from fire so
they can reproduce. The plant adaptations that these both ecosystems have got to go
through are totally different.
These different ecosystems have gone through so many different adaptations that have
helped them evolve through time. The differences between the rain forest el Yunque
and the Guanica dry forest are their distribution patterns, the precipitation, their
plants, animals, temperature and their human interact within these ecosystems. They
are the total opposite, one has a great diversity among species and the other has a
narrower scale of species. Both of them make great contributions to this island, by
helping us study their different adaptations it has helped us identify how evolution
and natural selection are an important aspect of nature.