DRY TROPICAL FOREST Alejandra Saavedra Sánchez & Andrés Felipe Pérez Romero
La Guajira is located in the north part of Colombia. It is often referred as the "poorest region" in the country due to the lack of interest from the government. La Guajira has had many difficulties with its water works as it is one of the driest parts of Colombia, leaving many of the deserted areas without water. In order to get some water in the region, local authorities have to use some extreme measures to provide the villages with potable water. One of the techniques they use is placing some large tubes down the soil to get to the natural sources and then bringing that drinkable water up by electronic motors. For these very reasons, the water usage in the region is limited and locals have to wait sometimes days to refill their water tanks.
Climate and Rain
The Issue •
In mid-2014 the Region was declared in "public calamity emergency in the face of the inability to meet the needs of 523,000 people, 60% of the population, according to Interior Secretary Wilson Rojas" ( Revista Semana).
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The mortality rate for children under-five is 45 from every 1,000 births.
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Acording to El DANE, between 2008 and 2013 in the department 4,151 children died: 278 for malnutrition, 2,671 for diseases that could have been treated and 1,202 who were not born due to lack of prenatal controls.
Dry Tropical Forest • It is the forest of dry tropical climate, which presents dry season in which vegetation adapts to long periods of aridity, during which evaporation is very active. • Evapotranspiration exceeds precipitation for enough of the year to have a significant effect on the vegetation.
CACTUS Ă“RGANO O CHILAYO is able to survive and grow in harsh, dry and deserted conditions. The spines on
the cactus help to protect itself from humans and animals. Its roots are spread out to collect water when it rains and it can store the water in its body for future use. A cactus can survive for years without any rainstorms, just by living off the water it stores.
• Spines instead of leaves: cactuses do not need leaves for photosynthesis. The added advantage of that is that the dry tropical forest has plenty of sunshine, so it is easy for the stems to have access to sunlight. The spines avoid the water evaporation because they work by blocking the pores of the skin, keeping the water inside the trunk, and as well the spines provide shallow to the plant.
• Shallow root systems for quick water absorption: The cactus plants have shallow roots that absorb water from the ground, the roots are also extended to enable them to cover a large area. After water intake, the roots then transport this water to the stems for storage.
• Water storage system: The trunk of the cactus has cells that allow the holding of the H2O, due to the high temperatures the water evaporates inside the cactus and turns again into water. In dry tropical deserts the rain sporadic, the feature of the cells allow the plant to store water for lengthy amounts of time, before the next rainfall.
• Waxy skin for water retention: The plant’s surface has a waxy skin. This skin covers the whole plant and helps to avoid water evaporation. The wax also helps to keep the plants cool in hot climates. In the nights, the waxy skin dries out, letting the inhalation and exhalation of carbon dioxide and oxygen, a necessary process to complete the photosynthesis process.
• Expandable system for maximum water intake: To enable the plants to store as much water as possible during the rainy season, the cactus has an expandable system, which means that the cactus grows in the rainy season to have more space to keep the water. This process allows as much water intake as possible for use, during the days when there is no rain.
• Flowers for survival: After the rainy season the cactus plants give flowers which spread seeds after they dry out, to allow the growing of another cactus, the process that helps the survival of the plants in the hot weathers because the more cactuses there are, the more showdown can provide for the system.
PARQUE NACIONAL MACUIRA LA GUAJIRA, COLOMBIA
Macondo or cavanillesia platanifolia: is a very representative Colombian tree because of the fictional town in "Cien AĂąos de Soledad". Is one of the biggest trees in the colombian tropical dry forest and due to its anatomy, the Macondo tree can survive and grow in dry climates.
Macondo or cavanillesia
platanifolia • Reaches up to 35 meters in height • Thick and shiny stem • Has a group of thick branches almost horizontal at the top • Its flowers are yellowish or reddish and bell-shaped
• The roots: The Macondo tree has a thick and long root that allows it to reach deep water. • The bread: Is able to store water in the cortical cells of their trunk. Sometimes this gives the trunk a swollen appearance. It has thicker bark as an antifire adaptation to dry areas. • The leaves: The Macondo tree loses its leaves at the onset of the dry season to reduce water loss.
à RBOL DE JOSUÉ: is able to survive and
grow in the dry tropical deserts. The trunk of the tree keeps the water and has cells that oxygenate the water inside. Its roots spread out to collect water when it rains. The leaves provide
shadow
and
photosynthesis process.
help
with
the
• Leaves for sun blocking: The leaves of the tree provide shadow to keep the internal temperature fresh and avoid the water evaporation and as well the form of the leaves help when it rains so that the water can go close to the roots to absorb the water easily. • Shallow root systems for quick water absorption: The tree has shallow roots that absorb water from the ground, the roots are long and go deep so they are able to cover a larger area. After water intake, the roots then transport this water to the vascular cylinder. • Water retention: The tree has petiole Xylem that are spaces inside the trunk that allow inhalation and exhalation of carbon dioxide
and
oxygen,
photosynthesis process.
necessary
to
complete
the
• Water storage system: The trunk of the tree has a vascular cylinder that contains cells that allow the holding of the H2O, due to the high temperatures the water evaporates inside the tree and turns again into water, keeping the water in the particles of the wood, which are harder to dry out because the vascular cylinder has a fresh temperature.
• Harsh skin for sun protection: The skin of the tree is made of more than a 100 layers which helps to keep the inside of the trunk fresh to avoid water evaporation. The harsh skin blocks the sunlight and in the warm season produces a slimy liquid that helps to cool down the tree.
References •
https://www.las2orillas.co/que-sucede-en-la-guajira/
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https://www.telesurtv.net/multimedia/Retratos-de-los-ninos-con-hambre-en-la-Guajira-colombiana-20160210-0037.html
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https://agronegocios.uniandes.edu.co/2015/02/04/el-agua-en-la-guajira/
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https://cactusway.com/how-does-a-cactus-survive-in-the-desert/
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https://www.accessscience.com/content/adaptations-of-the-joshua-tree-yucca-brevifolia/BR0819145
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https://www.nationalgeographic.com/environment/2018/10/joshua-trees-moths-threatened-climate-change-scientists-seek-solutions/
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https://www.nationalgeographic.com/news/2015/10/151028-joshua-tree-climate-change-mojave-desert/
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https://www.bbc.co.uk/bitesize/clips/z69rkqt
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https://askdruniverse.wsu.edu/2018/05/10/cacti-survive-hot-dry-environments/
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https://wonderopolis.org/wonder/how-does-a-cactus-live-without-water
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https://www.pugetsound.edu/academics/academic-resources/slater-museum/biodiversity-resources/world-biomes/characteristics-ofbioclimatic/tropical-dry-forest/
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https://ceiba.org/conservation/dry-forests/
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http://www.museobolivariano.org.co/cavanillesia-platanifolia-macondo/
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https://www.elheraldo.co/tendencias/el-macondo-verdadero-que-le-da-origen-al-nombre-del-pueblo-149656
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https://youtu.be/TLUrsBQM5hY