The forests lie in the path of wet winds blowing in from the Pacific. Like other major rainforests, the jungles and mangrove swamps of Central America contain many plants and animals found nowhere else.
Central America is famous for its large number of tropical birds, including many kinds of parrots. The Amazon jungle is the world's largest tropical rainforest. The forest covers the basin of the Amazon, the world's second longest river.
The Amazon is home to the greatest variety of plants and animals on Earth. Temperate rainforests are found mostly in coast al, mountainous areas. These geographic conditions help create areas of high rainfall. They are also much less sunny and rainy, receiving anywhere between centimeters inches of rain per year. Rainfall in these forests is produced by warm, moist air coming in from the coast and being trapped by nearby mountains. Temperate rainforests are not as biologically diverse as tropical rainforests.
They are, however, home to an incredible amount of biological productivity, storing up to metric tons of leaves, wood, and other organic matter per hectare metric tons per acre. Cooler temperatures and a more stable climate slow down decomposition, allowing more material to accumulate. The old-growth forest s of the Pacific Northwest, for example, produce three times the biomass living or once-living material of tropical rainforests.
This productivity allows many plant species to grow for incredibly long periods of time. Temperate rainforest trees such as the coast redwood in the U. The animals of the temperate rainforest are mostly made up of large mammals and small birds, insects, and reptiles. These species vary widely between rainforests in different world regions.
Bobcats, mountain lions, and black bears are major predators in the rainforests of the Pacific Northwest. Rainforests have been home to thriving, complex communities for thousands of years.
For instance, unique rainforest ecosystems have influenced the diet of cultures from Africa to the Pacific Northwest. The Mbuti, a community indigenous to the Ituri rainforest in Central Africa, have traditionally been hunter-gatherers. Their diet consists of plants and animals from every layer of the rainforest. From the forest floor, the Mbuti hunt fish and crabs from the Ituri River a tributary of the Congo , as well as gather berries from low-lying shrubs.
The giant forest hog, a species of wild boar, is also frequently targeted by Mbuti hunters, although this species is hunted for sale more often than food. From the understory, the Mbuti may gather honey from bee hives, or hunt monkeys.
From the canopy and emergent layers, Mbuti hunters may set nets or traps for birds. Although they are a historically nomadic society, agriculture has become a way of life for many Mbuti communities today as they trade and barter with neighboring agricultural groups such as the Bantu for crops such as manioc, nuts, rice, and plantains. The Chimbu people live in the highland rainforest on the island of New Guinea. The Chimbu practice subsistence agriculture through shifting cultivation.
This means they have gardens on arable land that has been cleared of vegetation. A portion of the plot may be left fallow for months or years. The plots are never abandoned and are passed on within the family.
Crops harvest ed in Chimbu garden plots include sweet potatoes, bananas, and beans. The Chimbu also maintain livestock , particularly pigs. In addition to their own diet, pigs are valuable economic commodities for trade and sale.
The temperate rainforest of the northwest coast of North America is the home of the Tlingit. The Tlingit enjoy a diverse diet, relying on both marine and freshwater species, as well as game from inland forests.
Due to bountiful Pacific inlets, rivers, and streams, the traditional Tlingit diet consists of a wide variety of aquatic life: crab, shrimp, clams, oysters, seals, and fish such as herring, halibut, and, crucially, salmon. Kelps and other seaweed s can be harvested and eaten in soups or dried. In more inland areas, historic Tlingit hunters may have targeted deer, elk, rabbit, and mountain goats. Plants gathered or harvested include berries, nuts, and wild celery.
The Yanomami are a people and culture native to the northern Amazon rainforest, spanning the border between Venezuela and Brazil. Like the Chimbu, the Yanomami practice both hunting and shifting-cultivation agriculture. Game hunted by the Yanomami include deer, tapirs an animal similar to a pig , monkeys, birds, and armadillos. The Yanomami have hunting dogs to help them search the understory and forest floor for game. The Yanomami practice slash-and-burn agriculture to clear the land of vegetation prior to farming.
Crop s grown include cassava, banana, and corn. In addition to food crops, the Yanomami also cultivate cotton, which is used for hammocks, nets, and clothing. Rainforests are critically important to the well-being of our planet. Tropical rainforests encompass approximately 1. Massive amounts of solar radiation are absorbed, helping regulate temperatures around the globe. Rainforests provide us with many products that we use every day. Tropical woods such as teak, balsa, rosewood, and mahogany are used in flooring, doors, windows, boatbuilding, and cabinetry.
Fibers such as raffia, bamboo, kapok, and rattan are used to make furniture, baskets, insulation , and cord. Cinnamon, vanilla, nutmeg, and ginger are just a few spices of the rainforest. The ecosystem supports fruits including bananas, papayas, mangos, cocoa and coffee beans. Rainforests also provide us with many medicinal products. According to the U. Rainforest plants are also used in the creation of muscle relaxants, steroid s, and insecticide s. They are used to treat asthma , arthritis , malaria , heart disease, and pneumonia.
The importance of rainforest species in public health is even more incredible considering that less than one percent of rainforest species have been analyze d for their medicinal value.
A mushroom discovered in the tropical rainforest of Ecuador, for example, is capable of consuming polyurethane —a hard, durable type of plastic used in everything from garden hoses to carpets to shoes. The fungi can even consume the plastic in an oxygen-free environment, leading many environmentalists and businesses to invest in research to investigate if the fungi can help reduce waste in urban landfill s.
Rainforests are disappearing at an alarmingly fast pace, largely due to human development over the past few centuries. Since , the total area of tropical rainforests has probably been reduced by more than half, to about 6. Rampant deforestation could cause many important rainforest habitats to disappear completely within the next hundred years.
Such rapid habitat loss is due to the fact that 40 hectares acres of rainforest are cleared every minute for agricultural and industrial development. In the Amazon rainforest, large-scale agricultural industries, such as cattle ranching , clear huge tract s of forests for arable land. In the Congo rainforest, roads and other infrastructure development have reduced habitat and cut off migration corridor s for many rainforest species.
Throughout both the Amazon and Congo, mining and logging operations clear-cut to build roads and dig mines. Some rainforests are threatened by massive hydroelectric power projects, where dam s flood acres of land. Development is encroach ing on rainforest habitats from all sides.
Economic inequalities fuel this rapid deforestation. Many rainforests are located in developing countries with economies based on natural resource s. Wealthy nations drive demand for products, and economic development increases energy use.
These demands encourage local governments to develop rainforest acreage at a fraction of its value. Impoverished people who live on or near these lands are also motivated to improve their lives by convert ing forests into subsistence farmland. Many individuals, communities, governments, intergovernmental organizations, and conservation groups are taking innovative approaches to protect threatened rainforest habitats. Many countries are supporting business es and initiative s that promote the sustainable use of their rainforests.
Costa Rica is a global pioneer in this field, investing in ecotourism projects that financially contribute to local economies and the forests they depend on. The country also signed an agreement with an American pharmaceutical company, Merck, which sets aside a portion of the proceeds from rainforest-derived pharmaceutical compounds to fund conservation projects.
Intergovernmental groups address rainforest conservation at a global scale. The Democratic Republic of the Congo used REDD funds to create an online National Forest Monitoring System that tracks and maps data on logging concession s, deforestation in protected areas, and national forestry sector measures.
REDD funds were also used to investigate best practices in solving land dispute s in Cambodia, which lacks proper forest zoning and boundary enforcement. Nonprofit organizations are tackling rainforest conservation through a variety of different approaches. The Rainforest Trust, for example, supports local conservation groups around the world in purchasing and managing critically important habitats.
Partnering with Burung Indonesia, the Trust created a 8,hectare 22,acre reserve on Sangihe Island to protect the highest concentration of threatened bird species in Asia. The Rainforest Alliance is a nonprofit organization that helps businesses and consumers know that their products conserve rather than degrade rainforests. Products that bear the Rainforest Alliance seal contain ingredients from farms or forests that follow strict guidelines designed to support the sustainable development of rainforests and local communities.
The Alliance also allows tourism businesses use of their seal after they complete an education program on efficiency and sustainability.
In turn, this seal allows tourists to make ecologically smart vacation plans. Kapok trees are keystone species in many rain forest ecosystems. Photograph by Steve Winter, National Geographic. Because of the small amount of sunlight and rainfall these plants receive, they adapt easily to home environments. The bottom layer or floor of the rainforest is covered with wet leaves and leaf litter.
This material decomposes rapidly in the wet, warm conditions like a compost pile sending nutrients back into the soil. Few plants are found on the floor of the forest due to the lack of sunlight. However, the hot, moist atmosphere and all the dead plant material create the perfect conditions in which bacteria and other microorganisms can thrive.
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