Language

The tropical rainforest is home to more than 50 percent of life on Earth. The rainforests help maintain climate by absorbing carbon dioxide and releasing oxygen. They also play a critical role in the hydrologic cycle. In addition, they are home to thousands of plant species, many of which hold medicinal secrets. They are, therefore, major contributors to the stability of earth’s life support system. If we know that the rainforest is beneficial to us, why do we continue to destroy these forests at the alarming rate of 80,000 acres a day?

Costa Rica rain forest with river running through it

One hundred years ago, the tropical rainforests covered 14 percent of the Earth's surface. Now only 6 percent remains. Edward O. Wilson, a leader in conservation biology, predicts that half of the world’s rainforests will vanish in 30 years with a loss of 4,000-6,000 species per year. Due to the destruction that we are causing we do not know what we are losing because little is known about what treasures these forests hold. Deforestation leads to fragmentation and edge effect. In addition, huge amounts of pesticides are released into the environment each day due to over-usage at large scale agricultural plantations.

Deforestation
• Deforestation is the cutting down and clearing away of trees from forests.

deforestation of rain forest

Causes include:  

  • Clear cutting for logging
  • Forest conversion for large scale agriculture purposes (e.g. banana plantations, coffee plantations, palm oil plantations, soybeans)
  • Slash and burn methods to allow for continued subsistence farming 
  • Urban growth 
  • Mining operations 
  • Dam construction

 cut logs of giant tree trunks 

Fragmentation
• Fragmentation is the splitting of large patches of forest into one or more smaller patches. Often this is one of the effects of deforestation.

fragmentation of rain forest with one patch spared

• Some results of fragmentation are loss of habitat that large animals need. Large animals, like jaguars, require significant parcels of intact rainforest. Fragmentation severely hinders their survival. This is the same reason why large birds of prey, like the harpy eagle, are almost non-existent.
• Infrastructures such as roadways divide the land and add to the increasing numbers of animals that are being separated and cut off from each other. Roads act as barriers that significantly prevent movement of animals.

Forest Degradation
• Forest degradation is different from deforestation. Deforestation refers to the removal of an existing forest. Forest degradation refers to an alteration of the existing forest which leads to loss of habitats, an inability of the trees to replace themselves naturally, erosion and ultimate reduction in plant and animal diversity.

forest degradation and deforestation

Causes include:

  • Most forms of logging for timber harvesting and “selective logging,” where only certain trees are cut down with incidental damage to non-targeted trees.
  • Over-grazing of livestock to supply cheaper sources of beef 
  • Slash and burn methods
  • Over harvesting for fuel wood
  • Wildfires that burn leaf litter and small plants but leave the canopy
  • Over-harvesting of non-wood forest products, like medicinal plants, foods, and fibers
  • Over-hunting
  • Invasive species
  • Oil pollution 
  • Storm damage 
  • Extreme drought 
  • Air pollution and acid rain

Edge Effect
• Edge effect is the boundary between older forest and newly harvested area that affects the conditions within the forest.

• Often these effects can be felt 100-200 meters into the forest.

• Some results from the “edge” are changes in:
- Light intensity
- Temperature variation
- Wind velocity
- Relative humidity
• Edge effect leads to loss of:
- Adequate habitat to support life and also to avoid predators
- Loss of food sources
- Loss of biodiversity
- Increased exposure to elements
- Increased competition between introduced and native species

Pesticide Usage
• Pesticides pose serious health risks to those who apply them, those who purchase them, and surrounding habitats.

• Banana plantations use tons of pesticides per year that cause health conditions for their workers and have killed thousands of insects and plants that have come in contact with them. There are approximately 250 to 300 cases of human pesticide poisoning each year in Costa Rica.

Plane spraying pesticide over ground

• Pesticides can also be blamed for the decline in bird populations. It was not until 1988 that Costa Rica banned DDT, a pesticide which made the shell of an egg so fragile that when they were incubated the egg would be crushed. 

Coral Reefs 
Coral reefs contain one-third of the ocean’s fish species in only 0.2 percent of its surface area. These habitats have been built up over a millennia, but 20 percent have already been destroyed and degraded and all may be lost within 100 years at current rates of destruction.

Coral reefs are being lost at an alarming rate due to destructive practices by humans that have led to increases in global temperatures with subsequent rises in water levels and ocean temperatures. Human populations are increasingly concentrated in coastal areas, causing 20 percent of these areas to become degraded or highly modified. Issues impacting these reefs include intensive harvesting of fish, shellfish, seaweed, and other marine products as well as dredging, pollution, sedimentation, destructive fishing practices and introduction of invasive species.

Global warming is causing the melting of mountain glaciers and polar ice caps, causing water levels to rise. As water temperatures rise, tiny symbiotic algae (zooxanthellae), whose presence is critical to the well-being of the coral, are lost. This is because the zooxanthellae provide essential carbohydrates as food for their coral hosts. Dead, the corals lose pigmentation and take on a white, almost bleached appearance--hence the term “bleaching.” If these increasing temperatures continue, decades from now this could be disastrous for coral reefs worldwide and the marine species that depend on them. Also, increased carbon dioxide levels in the atmosphere is causing an increase in the acidity of ocean waters, which reduce the ability of these marine species to secrete their calcium carbonate skeletons.

What can we do?
We need to step back and realize that it is we humans who are destroying these places that have survived millions of years before us. Our activities need to change or it is estimated that in the next 100 years the tropical rainforests and coral reefs will no longer exist.

Conservation is critical. Several organizations and conservation-minded business people are contributing in significant ways toward these efforts. Research in tropical ecosystems coupled with sustainable ecotourism practices are helping to develop a more stewardly approach to the conservation of the tropics.  

Examples include: the Caribbean Conservation Corporation (CCC), whose mission is to protect sea turtles and the habitats upon which they depend. To achieve their mission, the CCC uses research, habitat protection, public education, community outreach, networking, and advocacy as its basic tools.
 Caribbean Conservation Corporation logo     

The Organization for Tropical Studies (OTS) has a goal to contribute to the appreciation, understanding, and protection of nature and the human environment. OTS owns and operates three biological stations in Costa Rica, where more than 300 scientists from 25 countries work each year.

Ecotourism is an environmentally responsible way to travel to natural areas to enjoy and appreciate nature. Lodges like Almonds and Corals encourage the use a low impact visitor behavior and education to support local conservation efforts. They promote sensitivity of and appreciation for local indigenous cultures, encourage sustainable benefits to local communities, and offer educational components for both the traveler and local communities.

Education is key to changing and learning what we can do to help preserve these forests before it is too late. Once these amazing places are gone, they are gone forever so we must take action now to educate others and preserve and protect them while there is still time.

Printer-friendly version