The Amazon rainforest, also called Amazon jungle or Amazonia, is a moist broadleaf tropical rainforest in the Amazon biome that covers most of the Amazon basin of South America. This basin encompasses 7,000,000 km2 (2,700,000 sq mi), of which 5,500,000 km2 (2,100,000 sq mi) are covered by the rainforest. This region includes territory belonging to nine nations and 3,344 formally acknowledged indigenous territories.
Conservation biology is the study of the conservation of nature and of Earth's biodiversity with the aim of protecting species, their habitats, and ecosystems from excessive rates of extinction and the erosion of biotic interactions. It is an interdisciplinary subject drawing on natural and social sciences, and the practice of natural resource management.
A keystone species is a species that has a disproportionately large effect on its natural environment relative to its abundance, a concept introduced in 1969 by the zoologist Robert T. Paine. Keystone species play a critical role in maintaining the structure of an ecological community, affecting many other organisms in an ecosystem and helping to determine the types and numbers of various other species in the community. Without keystone species, the ecosystem would be dramatically different or cease to exist altogether. Some keystone species, such as the wolf, are also apex predators.
Bushmeat is meat from wildlife species that are hunted for human consumption. Bushmeat represents a primary source of animal protein and a cash-earning commodity in poor and rural communities of humid tropical forest regions of the world.
An ecological or environmental crisis occurs when changes to the environment of a species or population destabilizes its continued survival. Some of the important causes include:
Habitat fragmentation describes the emergence of discontinuities (fragmentation) in an organism's preferred environment (habitat), causing population fragmentation and ecosystem decay. Causes of habitat fragmentation include geological processes that slowly alter the layout of the physical environment, and human activity such as land conversion, which can alter the environment much faster and causes the extinction of many species. More specifically, habitat fragmentation is a process by which large and contiguous habitats get divided into smaller, isolated patches of habitats.
Habitat destruction occurs when a natural habitat is no longer able to support its native species. The organisms once living there have either moved to elsewhere or are dead, leading to a decrease in biodiversity and species numbers. Habitat destruction is in fact the leading cause of biodiversity loss and species extinction worldwide.
Reconciliation ecology is the branch of ecology which studies ways to encourage biodiversity in the human-dominated ecosystems of the anthropocene era. Michael Rosenzweig first articulated the concept in his book Win-Win Ecology, based on the theory that there is not enough area for all of earth's biodiversity to be saved within designated nature preserves. Therefore, humans should increase biodiversity in human-dominated landscapes. By managing for biodiversity in ways that do not decrease human utility of the system, it is a "win-win" situation for both human use and native biodiversity. The science is based in the ecological foundation of human land-use trends and species-area relationships. It has many benefits beyond protection of biodiversity, and there are numerous examples of it around the globe. Aspects of reconciliation ecology can already be found in management legislation, but there are challenges in both public acceptance and ecological success of reconciliation attempts.
Lee Hannah is a conservation ecologist and a Senior Researcher in Climate Change Biology at Conservation International. Hannah is one of many authors who published an article predicting that between 15% and 37% of species are at risk of extinction due to climate change caused by human greenhouse gas emissions.
Global biodiversity is the measure of biodiversity on planet Earth and is defined as the total variability of life forms. More than 99 percent of all species that ever lived on Earth are estimated to be extinct. Estimates on the number of Earth's current species range from 2 million to 1 trillion, but most estimates are around 11 million species or fewer. About 1.74 million species were databased as of 2018, and over 80 percent have not yet been described. The total amount of DNA base pairs on Earth, as a possible approximation of global biodiversity, is estimated at 5.0 x 1037, and weighs 50 billion tonnes. In comparison, the total mass of the biosphere has been estimated to be as much as 4 TtC (trillion tons of carbon).
Defaunation is the global, local, or functional extinction of animal populations or species from ecological communities. The growth of the human population, combined with advances in harvesting technologies, has led to more intense and efficient exploitation of the environment. This has resulted in the depletion of large vertebrates from ecological communities, creating what has been termed "empty forest". Defaunation differs from extinction; it includes both the disappearance of species and declines in abundance. Defaunation effects were first implied at the Symposium of Plant-Animal Interactions at the University of Campinas, Brazil in 1988 in the context of Neotropical forests. Since then, the term has gained broader usage in conservation biology as a global phenomenon.
Stuart Leonard Pimm is the Doris Duke Chair of Conservation Ecology at Duke University. His early career was as a theoretical ecologist but he now specialises in scientific research of biodiversity and conservation biology.
In ecology, extinction debt is the future extinction of species due to events in the past. The phrases dead clade walking and survival without recovery express the same idea.
Joe Roman is a conservation biologist, academic, and author of the books Whale and Listed: Dispatches from America's Endangered Species Act. His conservation research includes studies of the historical population size of whales, the role of cetaceans in the nitrogen cycle, the relationship between biodiversity and disease, and the genetics of invasions. He is the founding editor of "Eat the Invaders", a website dedicated to controlling invasive species by eating them.
Conservation behavior is the interdisciplinary field about how animal behavior can assist in the conservation of biodiversity. It encompasses proximate and ultimate causes of behavior and incorporates disciplines including genetics, physiology, behavioral ecology, and evolution.
Lian Pin Koh is a Singaporean conservation scientist. He is the Kwan Im Thong Hood Cho Temple Professor of Conservation, Vice Dean of Research at the Faculty of Science, Director of the Centre for Nature-based Climate Solutions, and Director of the Tropical Marine Science Institute at the National University of Singapore (NUS).
Yadvinder Singh Malhi is professor of Ecosystem Science at the University of Oxford and a Jackson Senior Research Fellow at Oriel College, Oxford.
Road expansion refers to the increasing rate at which roads are constructed globally. Increases in population size and GDP, particularly in developing nations, are the primary drivers of road expansion but transportation planning decisions also play an important role. The anticipated length of newly paved roads to be built between 2010 and 2050 would encircle the planet more than 600 times. Approximately 90% of the new roads are being built in developing nations. Africa and Southeast Asia are predicted to experience a large amount of road expansion shortly.
Felicia Keesing is an ecologist and the David & Rosalie Rose Distinguished Chair of the Sciences, Mathematics, and Computing at Bard College in Annandale-on-Hudson, New York.
James R. Karr is an ecologist, ornithologist, conservation biologist, stream ecologist, academic, and author. He is a Professor Emeritus of Aquatic and Fishery Sciences at the University of Washington, Seattle.
