Environment, SUM-WHA
Biological diversity is key to a healthy ecosystem, whether it’s a small biological community or the global biosphere. Ecology, which studies the relationships between organisms and their environment, is an invaluable science that helps us understand what allows an ecological community to thrive.
Environment Encyclopedia Articles By Title
Summer
Summer, warmest season of the year, between spring and autumn. In the Northern Hemisphere, it is usually defined......
Sundarbans National Park
Sundarbans National Park, large natural area in extreme southeastern West Bengal state, eastern India. The park,......
Sunset Crater Volcano National Monument
Sunset Crater Volcano National Monument, geologic formation in north-central Arizona, U.S. The monument lies 15......
Superfund
Superfund, U.S. government fund intended to pay for the cleanup of hazardous-waste dump sites and spills. The 1980......
survivorship curve
survivorship curve, graphic representation of the number of individuals in a population that can be expected to......
sustainability
sustainability, the long-term viability of a community, set of social institutions, or societal practice. In general,......
Suzuki, David
David Suzuki is a Canadian scientist, television personality, author, and environmental activist who is known for......
Swaminathan, M.S.
M.S. Swaminathan was an Indian geneticist and agricultural scientist who spearheaded India’s agricultural transformation.......
Swiss National Park
Swiss National Park, national park in Graubünden canton, southeastern Switzerland, adjoining the Italian border......
symbiosis
symbiosis, any of several living arrangements between members of two different species, including mutualism, commensalism,......
Syntrophism
Syntrophism, mutual dependence of different types of organisms for the satisfaction of their respective nutritional......
systems ecology
systems ecology, Branch of ecosystem ecology (the study of energy budgets, biogeochemical cycles, and feeding and......
Tablas de Daimiel National Park
Tablas de Daimiel National Park, nature reserve and wetland ecosystem, located about 19 miles (30 km) northeast......
Tadoba National Park
Tadoba National Park, national park in eastern Maharashtra state, western India. It was established as a wildlife......
Taiga
Taiga, biome (major life zone) of vegetation composed primarily of cone-bearing needle-leaved or scale-leaved evergreen......
Talking Ocean Trash: Ghost Gear Keeps on Fishing
An earlier version of this article was published on the Britannica blog Advocacy for Animals. In July 2015 a piece......
Tatshenshini-Alsek Wilderness Provincial Park
Tatshenshini-Alsek Wilderness Provincial Park, wilderness park, extreme northwestern British Columbia, Canada,......
Taï, Parc National de
Parc National de Taï, national park, southwestern Côte d’Ivoire (Ivory Coast), situated between the Liberian border......
Temperate forest
Temperate forest, vegetation type with a more or less continuous canopy of broad-leaved trees. Such forests occur......
Temperate rainforest
Temperate rainforest, in ecology, a biome dominated by a mix of broad-leaved or coniferous trees that occurs in......
territory
territory, in ecology, any area defended by an organism or a group of similar organisms for such purposes as mating,......
The Arctic’s Seed-Filled Doomsday Fortress
Beyond the Arctic Circle lies the Svalbard Global Seed Vault, the world’s largest secure seed storage. Opened by......
The Darwin-Lincoln Double Bicentennial
Abraham Lincoln and Charles Darwin, two of the 19th century’s most enduring thinkers and figures, share more than......
The Perils of an Early Spring
Outside of the tropics, the spring season is a time of renewal as buds and leaves begin to sprout on trees and......
The Sahara Was Once Green
The Sahara, which covers the bulk of North Africa, is the world’s largest hot desert. It is a vast, desolate region......
The six criteria air pollutants
Empowered by the Clean Air Act of 1970, the U.S. Environmental Protection Agency (EPA) quickly established air......
thermal-heat recovery
thermal-heat recovery, use of heat energy that is released from some industrial processes and that would otherwise......
Thorn forest
Thorn forest, dense scrublike vegetation characteristic of dry subtropical and warm temperate areas with a seasonal......
Thousand Islands National Park
Thousand Islands National Park, national park covering an area of mainland, islands, and islets in southeastern......
Thunberg, Greta
Greta Thunberg was just eight years old when she became passionate about about climate change. By the time she......
timberline
timberline, upper limit of tree growth in mountainous regions or in high latitudes, as in the Arctic. Its location......
Timeline of Climate Change
This infographic presents a timeline of climate change. A detailed description of this infographic appears below.......
Timpanogos Cave National Monument
Timpanogos Cave National Monument, limestone cave system in American Fork Canyon, north-central Utah, U.S. The......
Today in History—April 14: The Volcanic Eruption That Grounded a Continent
On this day in 2010, Iceland’s Eyjafjallajökull volcano erupted in earnest. Small earthquakes had been rumbling......
Today in History—January 5: A Winter So Cold It Rewrote History
On January 5, 1709, Europe’s coldest winter in 500 years crept in overnight. The chill stretched from England to......
Today in History—July 2: The Canadian Cod Fishery Collapse
On this day in 1992, the Canadian government confirmed what thousands of people in Newfoundland and Labrador already......
Today in History—June 1: Czech Republic Passes “Dark-Sky” Law
On this day in 2002, one of the weirdest side effects of capitalism was thrust into the spotlight, literally: lighting.......
Today in History—June 28: A Milestone Moment for Bald Eagles
This day in 2007 represented a rare conservation victory: Bald eagles were removed from the endangered species......
Today in History—June 9: The Global Fraud Case About Toxic Waste
On this day in 1986, brothers Jack and Charles Colbert were found guilty in a New York courtroom of running what......
Today in History—March 1: The First National Park Is Founded
On this day in 1872 the United States did something new: Pres. Ulysses S. Grant signed the act establishing Yellowstone......
Today in History—May 9: Mr. Trash Wheel Goes on Duty
Baltimore has a new celebrity. He’s 16 feet tall, weighs almost 100,000 pounds, and eats a lot—nearly 500,000 pounds......
Today in History—October 20: The Monterey Bay Aquarium Opens
On this day in 1984, a former sardine factory on California’s historic Cannery Row began a remarkable new chapter:......
Today in History—September 5: The Garbage Ship Sets Sail
On this day in 1986, about 28 million pounds of incinerated garbage set sail from Philadelphia aboard a rusty ship......
Tongass National Forest
Tongass National Forest, forest region and wilderness area in southeastern Alaska, U.S. It was established in 1907......
toxic waste
toxic waste, chemical waste material capable of causing death or injury to life. Waste is considered toxic if it......
tragedy of the commons
tragedy of the commons, concept highlighting the conflict between individual and collective rationality. The idea......
trophic cascade
trophic cascade, an ecological phenomenon triggered by the addition or removal of top predators and involving reciprocal......
trophic level
trophic level, step in a nutritive series, or food chain, of an ecosystem. The organisms of a chain are classified......
trophic pyramid
trophic pyramid, the basic structure of interaction in all biological communities characterized by the manner in......
Tropical dry forest
Tropical dry forest, biome of any open woodland in tropical areas that have a long dry season followed by a season......
Tropical rainforest
Tropical rainforest, luxuriant forest found in wet tropical uplands and lowlands around the Equator. Tropical rainforests,......
Tsavo National Park
Tsavo National Park, national park, southeastern Kenya, east of Mount Kilimanjaro. The largest (8,036 square miles......
Tundra
Tundra, a major zone of treeless level or rolling ground found in cold regions, mostly north of the Arctic Circle......
Type I survivorship curve
Type I survivorship curve, in ecology, a curve displayed on a semilogarithmic scale that tracks organisms that......
Type II survivorship curve
Type II survivorship curve, in ecology, a curve displayed on a semilogarithmic scale that tracks organisms whose......
U.S. Death Toll During Major Events
This infographic shows the death toll caused by major events during the history of the United States, including......
U.S. Forest Service
U.S. Forest Service (USFS), federal agency within the U.S. Department of Agriculture (USDA) charged with oversight,......
Ujung Kulon National Park
Ujung Kulon National Park, national park on the island of Java, in the province of Banten, Indonesia. It is best......
Umfolozi Game Reserve
Umfolozi Game Reserve, wild animal sanctuary in northern KwaZulu/Natal province, South Africa. The reserve lies......
uMkhuze Game Reserve
uMkhuze Game Reserve, park in northern KwaZulu-Natal province, South Africa. The park, established in 1912, lies......
UNESCO
UNESCO, specialized agency of the United Nations (UN) that was outlined in a constitution signed November 16, 1945.......
Uninvited Guests: The 7 Worst Parasitic Worms
What’s slimy and spineless and looking to parasitize you? (They’re not running for office, if that narrows it down.)......
United Nations Conference on Environment and Development
United Nations Conference on Environment and Development (UNCED), conference held at Rio de Janeiro, Brazil (June......
United Nations Conference on the Human Environment
United Nations Conference on the Human Environment, the first United Nations (UN) conference that focused on international......
United Nations Environment Programme
United Nations Environment Programme (UNEP), organization established in 1972 to guide and coordinate environmental......
United Nations Population Fund
United Nations Population Fund (UNFPA), trust fund under the jurisdiction of the United Nations Development Programme......
Upemba National Park
Upemba National Park, park in southeastern Congo (Kinshasa). It was created in 1939 and has an area of 4,529 square......
Urban ecosystem
Urban ecosystem, any ecological system located within a city or other densely settled area or, in a broader sense,......
Vanoise National Park
Vanoise National Park, nature reserve in Savoie département, Rhône-Alpes région, southeastern France. It is contiguous......
Vavilov, Nikolai
Nikolai Vavilov was a Soviet plant geneticist whose research into the origins of cultivated plants incurred the......
veld
veld, name given to various types of open country in Southern Africa that is used for pasturage and farmland. To......
Virgin Islands Coral Reef National Monument
Virgin Islands Coral Reef National Monument, natural marine area lying off the island of St. John in the United......
Virunga National Park
Virunga National Park, park in northeastern Democratic Republic of the Congo (Kinshasa). Created in 1925, it has......
vital rates
vital rates, relative frequencies of vital occurrences that affect changes in the size and composition of a population.......
volcanic winter
volcanic winter, cooling at Earth’s surface resulting from the deposition of massive amounts of volcanic ash and......
Voyageurs National Park
Voyageurs National Park, region of lakes and wilderness in northern Minnesota, U.S. The park lies along the Canadian......
Wallace Line
Wallace Line, boundary between the Oriental and Australian faunal regions, proposed by the 19th-century British......
Ward, Barbara, Baroness Jackson
Barbara Ward, Baroness Jackson was a British economist and writer. After studying economics at the University of......
Warming, Johannes Eugenius Bülow
Johannes Eugenius Bülow Warming was a Danish botanist whose work on the relations between living plants and their......
Water bloom
Water bloom, dense aquatic population of microscopic photosynthetic organisms produced by an abundance of nutrient......
Water cycle
Water cycle, cycle that involves the continuous circulation of water in the Earth-atmosphere system. Of the many......
water pollution
water pollution, the release of substances into subsurface groundwater or into lakes, streams, rivers, estuaries,......
water purification
water purification, process by which undesired chemical compounds, organic and inorganic materials, and biological......
water resource
water resource, any of the entire range of natural waters that occur on the Earth, regardless of their state (i.e.,......
water scarcity
water scarcity, insufficient freshwater resources to meet the human and environmental demands of a given area.......
Water Scarcity Facts and Statistics
Water scarcity results from insufficient available freshwater resources to meet the human and environmental demands......
water supply
water supply, available water provided to fulfill a particular need. If the need is domestic, industrial, or agricultural,......
Watson, Paul
Paul Watson is a Canadian American environmental activist who founded (1977) the Sea Shepherd Conservation Society,......
What Are the Different Types of Pollution?
Pollution can be described as a nutrient or substance that is out of place. More specifically, however, it is the......
What causes acid rain?
The main contributors to acid rain are sulfur dioxide (SO2) and nitrogen oxides (NOx; the combination of NO and......
What do ants eat?
There are approximately 10,000 species of ants on Earth, with a wide range of diets and behaviors among them. Many......
What eats snakes?
Although snakes are predators, they are also themselves eaten by other creatures, making them secondary consumers......
What Happened to Acid Rain?
During the 1970s and ’80s the phenomenon called acid rain was one of the most well-known environmental problems......
What Happens to Earth If the Amazon Rainforest Is Completely Burned?
Metaphorically speaking, the vast tropical rainforest in South America’s Amazon River basin is often called the......
What Is a Whale Graveyard?
You might have heard of elephant graveyards—that is, the final resting places where, according to legend, old,......
What Is Known (and Not Known) About the Tunguska Event
Rumors, conjecture, and conspiracy theories swirl around the explosion that happened near the Podkamennaya Tunguska......
What Is the Christmas Bird Count?
The Christmas Bird Count is an annual large-scale bird census organized by the National Audubon Society—a U.S.-based......
What is the coldest temperature ever recorded on Earth?
Antarctica holds the record for the lowest temperature ever recorded on Earth. At Vostok Station, a Russian research......
What Is the Deadliest Wildfire in History?
Wildfires erupt from a deadly confluence of extreme weather conditions and primed fuel sources. Drought, heat,......
What Is the Difference Between Primary and Secondary Ecological Succession?
Ecosystems are not static things. Wetlands and grasslands, patches of forests, and even whole landscapes (which......