1. Recinto Universitario <br />Cayey, Puerto Rico<br />General Biology I <br />Differences in abiotic and biotic factors in different ecosystems<br />Dr. Edwin Vázquez<br />Pablo A. González<br />Osvaldo J. Vega<br />Wilmarie Morales<br />Daneisha Bonilla<br />Michelle De Jesus<br />Yadmaris E. Laborde<br />Carlos Montosa <br />Jeremy Rios <br />Differences in abiotic and biotic factors in different ecosystems<br /> The rainforest “El Yunque” is a cool mountainous, subtropical forest that consists of 28,000 acres. It is located on the eastern side of the Luquillo Mountains, and due to its high elevation receives most of the rain in the area. Average temperature at “El Yunque” is 77.9ºF at the lower elevations and 65.3ºF at elevations above 3,280 feet. It rains almost every day and the average rainfall is about 200 inches a year. This tropical rainforest is divided into four sections, those being: Tabonuco Forest, Palo Colorado Forest, Palma Sierra Forest and Bosque de las Nubes. In the Yunque we can find a variety of fauna including, reptiles, amphibians and birds such as the Puerto Rican parrot, coquies and the Puerto Rican boa. Flora is also a very important factor in this ecosystem due to the fact that it is part of all of the forest’s area. Orchids, ferns and different tree species are a big part of the forest’s plant ecosystem. <br /> The Dry Forest of Guanica, also known as the Xerophilic Forest is located on the southwestern side of Puerto Rico and covers 11,000 miles between the towns of Guanica, Guayanilla and Yauco. The temperature in this area generally is between 80 degrees F and 100 degrees F and therefore it receives high levels of radiation and very little rain, about 30 inches a year. Most of the flora in this forest is composed of trees and spiny shrubs adapted to living with sparse water, high wind velocity and high levels of salt. Of these plants, 16 species are endemic. There also is a small variety of Fauna including, 160 species of birds and the “sapo concho” (and endangered species of Puerto Rico). In this forest we can find plants that have evolved in order to adapt to this harsh environment.<br />Methodology<br />Yunque:<br />Divide the 24 persons in 3 groups<br />Follow the leader<br />Take samples on every stop we did<br />The instruments list:<br /> -pH meter<br /> Measure how acidic or basic is the ground <br /> -Thermometer<br /> Measure the temperature of the ground<br /> -Wind velocity meter<br /> Measures wind velocity <br /> -GPS<br /> Takes coordinates and the altitude of the locations the samples were taken<br /> -Humidity meter<br /> Measure the humidity of the ground<br />Write the result in a table <br />Guanica:<br />Divided in the same groups as El Yunque<br />Instrument list:<br /> -Meter stick<br /> Used to measure ranges<br /> -Line transect <br /> Method used to analyze organisms within a certain range, in this case 50ft<br /> -Quadrant<br /> Square used to determine organisms inside it <br />Results: Tables<br />Guanica table<br />Guanica Group 1FeetLine transectPercent5ftA) Lime stone100%10ftA) Button Mangrove B) Lime stoneA)80%B)20%15ftA) Acacia B) lime stoneA)30%B)70%20ftA) grass100%25ftA) grass B) lime stoneA)85%B)1530ftA) grass100%35ftA) grass B) lime stoneA)40%B)60%40ftA) grass B) lime stoneA)10%B)90%45ftA) cactus B) grass C) lime stoneA)10%B)5%C)75%50ftA) grass B) lime stoneA)80%B)20%Guanica Group 3FeetLine transectCuadrant 5ftDistance from starting point98% grey dirt 2% spider10ft83% grass 17%plant50% rock 50% quicksand15ft67% grass 33% cotton5%cotton 75% rock 19% plant 1% seashell20ft57%gass 13% rock 27% plant(orange) 3% seashell80% black rock 3% seashell 17% plant (orange)25ft100% grass100% grass30ft92% grass 8% rock85%grass 15%rock35ft15% rock 68% brunt grass 17% plant (red)50%grass 50%rock40ft63% dry grass 28% plant 9% rock(white)95%rock 5% ants45ft40%grass 12% seashell 24% soil(red) 24% rock75% grass 5% ants 20% red soil50ft40%grass 27% plant 14% dead vegetation 7% ants 12% seashells97% rock 3% leaf Mother Plant Melocactus1st mother plantAliveDeadSeedlings1m0112m0003m1014m82105m3146m3037m0118m0009m00010m0002nd mother plant1m2022m84123m103134m1895m124166m133167m7188m73109m21310m3253rd Mother Plant1m0222m4043m5054m4155m2356m2137m1018m1249m23510m707Total seedlings10846154<br />El Yunque Tables<br />CoordinatesAltitudeTemperaturepHHumidity Soil sampleN 18° 21.985 W 065° 46.22849ft83˚ F 30˚ C6.860N 18° 18.335 W 065° 47.3472664ft70˚ F 24˚ C5NoN 18° 18.284 W 065° 47.5872888ft71˚ F 24˚C520NoN 18° 20.273 W 065° 45.73483˚ F 30˚ C6.840.9YesN 18° 18.297 W 065° 47.7212513ft80° F4.230YesN 18° 18.144 W 065° 47.0032571ft81.5° F4.240.5YesN 18° 18.568 W 065° 47.6643394ft76° F520YesN 18° 18.38 W 065° 47.263352ft76° F5.6YesN 18° 19.121 W 065° 46.228579ft79° F4.570%Yes <br />AltitudeCoordinatesHumiditypH Temperature Samples70618 ̊ 20.298'N 065 ̊45.732'W580 ̊FYes2,48318 ̊18.1989'N 065 ̊ 47.394'W84%73FYes5618 ̊ 21.985'N 065 ̊46.225'W80FNo26,62218 ̊298'N 065 ̊47.394'W71F Yes1,60518 ̊18.65'N 065 ̊46.227'W25%6.578F Yes3,42518 ̊18.633'N 065 ̊47.546'W7%Yes2,15318 ̊18.136'N 065 ̊47.047'W70%Yes<br />Conclusion:<br /> In our experimental field trip to the rain forest El Yunque we observed that many plants there had adventitious roots. These types of roots are an adaptation that help them better absorb nutrients and water from the environment. Some of the plants here like the Guaba tree, form symbiotic relationships with animals such as ants. These ants protect the tree by killing other vegetation that grows around. In return the trees provide a home for the ants. Other species of plants that we encountered there were the Yagrumo tree, the Caoba tree, and different types of ferns. Some of these ferns have dimorphic adaptations which enables them to have two types of growth. We also encountered a special type of grass called Bamboo. This type of grass is very important because it serves to stabilize the terrain; it helps prevent mud slides.<br /> During the fieldtrip we took different samples of terrain and we also measured the temperature, pH, humidity, and coordinates. To do this we used the tools mentioned in the table above. By the data listed in the table we determined that as the altitude increases, the temperature decreases. These factors affect the growth of vegetation. That is why there are many varieties of plants there with different evolutionary adaptations. Such as large leaves or adventitious roots. As we reached the top of the mountain we also noticed that the trees grew smaller and with many projections (branches). <br /> In the dry forest of Guanica we encountered different types of plants and animals. Some of these were the button mangrove, the Agave plant, the Melocactus, the cotton plant, the Acacia, and the Comocladia. Other types of plants don’t grow in the Guanica forest because salt in the environment creates a hypertonic solution in the roots of the plant. Most vegetation that grows in this forest has different adaptations for the dryness and salinity of the environment. Some of these adaptation are salt glands, which helps them excrete excess salt, succulent leaves that help store water, and thorns that protect them from predators. Most of the plants we observed, originated from Africa and were introduced to Puerto Rico. Examples of these are cotton acacia.<br /> With the help from the data tables we could observe that some of these plants like the Melocactus grow dispersed but others like the Agave, grow in clusters. This is due to the fact that they have different methods of reproduction. The Agave produces clones and the Melocactus produces seeds that can be dispersed by wild animals. They also have one thing in common, which is that they are both big-bang plants. This means that after they reproduce, they cease to live.<br /> If we compare both of these biomes we can see that they are complete opposites. This is because of many biotic and abiotic factors. One of these is that El Yunque has higher rain precipitation annually that the other, their temperature is different and the rainforest has much more humidity than the dry forest. Also vegetation in these ecosystems differ due to the fact of water distribution. For example El Yunque has higher diversity of animals and also has many layers of plants while Guanica’s dry forest doesn’t show much diversity of animals and plants are scattered. <br /> <br />