Topics include major events, persons, and issues spanning the period from the African heritage to contemporary times.
Amazon River rain forest in Peru Tropical rainforests can be characterized in two words: Tropical rainforests exhibit high levels of biodiversity. Tropical rainforests are among the most threatened ecosystems globally due to large-scale fragmentation as a result of human activity.
Habitat fragmentation caused by geological processes such as volcanism and climate change occurred in the past, and have been identified as important drivers of speciation.
Tropical rain forests have been subjected to heavy logging and agricultural clearance throughout the 20th century, and the area covered by rainforests around the world is rapidly shrinking. Most tropical rainforests today are on fragments of the Mesozoic era supercontinent of Gondwana.
Other types of tropical forest Several biomes may appear similar-to, or merge via ecotones with, tropical rainforest: Moist seasonal tropical forest Daintree "rainforest" in Queensland is actually a seasonal tropical forest. Moist seasonal tropical forests receive high overall rainfall with a warm summer wet season and a cooler winter dry season.
Some trees in these forests drop some or all of their leaves during the winter dry season, thus they are sometimes called "tropical mixed forest".
They are found in parts of South America, in Central America and around the Caribbeanin coastal West Africaparts of the Indian subcontinentand across much of Indochina. Montane rainforests These are found in cooler-climate mountainous areas, becoming known as cloud forests at higher elevations.
Forest structure Rainforests are divided into different strata, or layers, with vegetation organized into a vertical pattern from the top of the soil to the canopy. Only the emergent layer is unique to tropical rainforests, while the others are also found in temperate rainforests.
Only plants adapted to low light can grow in this region. Away from riverbanks, swamps and clearings, where dense undergrowth is found, the forest floor is relatively clear of vegetation because of the low sunlight penetration. This more open quality permits the easy movement of larger animals such as: The forest floor also contains decaying plant and animal matter, which disappears quickly, because the warm, humid conditions promote rapid decay.
Many forms of fungi growing here help decay the animal and plant waste. Understory layer Main article: Understory The understory layer lies between the canopy and the forest floor. The understory is home to a number of birds, small mammals, insects, reptiles, and predators.
Examples include leopard Panthera parduspoison dart frogs Dendrobates sp. As an adaptation to these low light levels, understory plants have often evolved much larger leaves.
Many seedlings that will grow to the canopy level are in the understory. Canopy ecology The canopy is the primary layer of the forest forming a roof over the two remaining layers. It contains the majority of the largest trees, typically 30—45 m in height.
Tall, broad-leaved evergreen trees are the dominant plants. The densest areas of biodiversity are found in the forest canopy, as it often supports a rich flora of epiphytesincluding orchids, bromeliads, mosses and lichens. These epiphytic plants attach to trunks and branches and obtain water and minerals from rain and debris that collects on the supporting plants.
The fauna is similar to that found in the emergent layer, but more diverse. It is suggested that the total arthropod species richness of the tropical canopy might be as high as 20 million. Balizia elegansDipteryx panamensisHieronyma alchorneoidesHymenolobium mesoamericanumLecythis ampla and Terminalia oblonga.
Several unique faunal species inhabit this layer such as the crowned eagle Stephanoaetus coronatusthe king colobus Colobus polykomosand the large flying fox Pteropus vampyrus.
Rainforests are dynamic and many changes affect the structure of the forest. Emergent or canopy trees collapse, for example, causing gaps to form. Openings in the forest canopy are widely recognized as important for the establishment and growth of rainforest trees.
In general, climatic patterns consist of warm temperatures and high annual rainfall. However, the abundance of rainfall changes throughout the year creating distinct moist and dry seasons. Tropical forests are classified by the amount of rainfall received each year, which has allowed ecologists to define differences in these forests that look so similar in structure.
However, most lowland tropical forests can be classified as tropical moist or wet forests, which differ in regards to rainfall. Tropical forest ecology- dynamics, composition, and function- are sensitive to changes in climate especially changes in rainfall.The Importance of Tropical Rainforest Conservation in the Modern Day world.
By Dusty Brett. Since the beginning of civilization, the tropical rainforests have been used to sustain the survival of people and facilitate trade between different groups. A useful revision guide explaining all about specialist input devices and their uses, such as concept keyboards and interactive whiteboards, for GCSE ICT.
JSTOR is a digital library of academic journals, books, and primary sources. View Essay - Tropical Rainforest_Essay_Human Impact from CHEM at Los Angeles City College.
Running head: MANMADE DESTRUCTION TO OUR TROPICAL RAINFORESTS The Effects of Manmade Destruction to Our. A newly released study, produced with help from eight universities, found some good news. Between and , the global impact of human activities on the terrestrial environment is expanding more slowly than the rates of economic and/or population growth.
New research suggests that between three million and million years ago, the diet of our very early ancestors in central Africa is likely to have consisted mainly of tropical grasses and sedges.