Environment Portal | Britannica

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Biological diversity, or biodiversity, is the variety of life either in a particular place or on... </div> </div> </div> </div> </div> <div class="p-10 d-inline-flex js-pin col-100 col-sm-33 col-md-25 "> <div class="card text-normal col-100 "> <div class="card-media position-relative"> <a href="https://www.britannica.com/topic/Environmental-Protection-Agency" style="--aspect-ratio: 16/9"> <img loading="lazy" src="https://cdn.britannica.com/22/141122-050-4CA8A447/headquarters-Environmental-Protection-Agency-Washington-DC.jpg?w=400&h=225&c=crop" alt="Environmental Protection Agency" class="col-100" /> </a> </div> <div class="col"> <div class="card-body text-hyphenate"> <a href="https://www.britannica.com/topic/Environmental-Protection-Agency" class="font-weight-bold font-16 lh-sm">Environmental Protection Agency</a> <div class="font-serif mt-10 font-14"> Environmental Protection Agency (EPA), agency of the U.S. government that sets and enforces national pollution-control standards. 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Water is the most... </div> </div> </div> </div> </div> <div class="p-10 d-inline-flex js-pin col-100 col-sm-33 col-md-25 "> <div class="card text-normal col-100 "> <div class="card-media position-relative"> <a href="https://www.britannica.com/science/environment" style="--aspect-ratio: 16/9"> <img loading="lazy" src="https://cdn.britannica.com/mendel-resources/3-130/images/shared/default3.png?v=3.130.14" class="default col-100" /> </a> </div> <div class="col"> <div class="card-body text-hyphenate"> <a href="https://www.britannica.com/science/environment" class="font-weight-bold font-16 lh-sm">environment</a> <div class="font-serif mt-10 font-14"> Environment, the complex of physical, chemical, and biotic factors that act upon an organism or an ecological community and ultimately determine its form and survival. 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The basic phases in recycling are the collection of waste materials, their processing or manufacture into new products,... </div> </div> </div> </div> </div> <div class="p-10 d-inline-flex js-pin col-100 col-sm-33 col-md-25 "> <div class="card text-normal col-100 "> <div class="card-media position-relative"> <a href="https://www.britannica.com/science/atmosphere" style="--aspect-ratio: 16/9"> <img loading="lazy" src="https://cdn.britannica.com/98/74598-050-C98CDE77/atmospheres-planets-solar-system-places-particulates-gases.jpg?w=400&h=225&c=crop" alt="feathery cirrus clouds over Pinawa Dam Provincial Park" class="col-100" /> </a> </div> <div class="col"> <div class="card-body text-hyphenate"> <a href="https://www.britannica.com/science/atmosphere" class="font-weight-bold font-16 lh-sm">atmosphere</a> <div class="font-serif mt-10 font-14"> Atmosphere, the gas and aerosol envelope that extends from the ocean, land, and ice-covered surface of a planet outward into space. The density of the atmosphere decreases outward, because the gravitational... </div> </div> </div> </div> </div> <div class="p-10 d-inline-flex js-pin col-100 col-sm-33 col-md-25 "> <div class="card text-normal col-100 "> <div class="card-media position-relative"> <a href="https://www.britannica.com/science/climate-change" style="--aspect-ratio: 16/9"> <img loading="lazy" src="https://cdn.britannica.com/50/112550-050-D7D94E18/Grinnell-Glacier-series-photographs-summit-Mount-Gould-2006.jpg?w=400&h=225&c=crop" alt="Grinnell Glacier shrinkage" class="col-100" /> </a> </div> <div class="col"> <div class="card-body text-hyphenate"> <a href="https://www.britannica.com/science/climate-change" class="font-weight-bold font-16 lh-sm">climate change</a> <div class="font-serif mt-10 font-14"> Climate change, periodic modification of Earth鈥檚 climate brought about as a result of changes in the atmosphere as well as interactions between the atmosphere and various other geologic, chemical, biological,... </div> </div> </div> </div> </div> <div class="p-10 d-inline-flex js-pin col-100 col-sm-33 col-md-25 "> <div class="card text-normal col-100 "> <div class="card-media position-relative"> <a href="https://www.britannica.com/science/tropical-rainforest" style="--aspect-ratio: 16/9"> <img loading="lazy" src="https://cdn.britannica.com/90/3890-050-F451C580/rainforest-coast-lowland-rainforests-Ecuador-tropics-evergreen.jpg?w=400&h=225&c=crop" alt="Ecuador: rainforest" class="col-100" /> </a> </div> <div class="col"> <div class="card-body text-hyphenate"> <a href="https://www.britannica.com/science/tropical-rainforest" class="font-weight-bold font-16 lh-sm">tropical rainforest</a> <div class="font-serif mt-10 font-14"> Tropical rainforest, luxuriant forest found in wet tropical uplands and lowlands around the Equator. Tropical rainforests, which worldwide make up one of Earth鈥檚 largest biomes (major life zones), are... </div> </div> </div> </div> </div> <div class="p-10 d-inline-flex js-pin col-100 col-sm-33 col-md-25 "> <div class="card text-normal col-100 "> <div class="card-media position-relative"> <a href="https://www.britannica.com/science/sustainability" style="--aspect-ratio: 16/9"> <img loading="lazy" src="https://cdn.britannica.com/19/196519-050-E9EE2978/Wind-turbines-field.jpg?w=400&h=225&c=crop" alt="renewable energy" class="col-100" /> </a> </div> <div class="col"> <div class="card-body text-hyphenate"> <a href="https://www.britannica.com/science/sustainability" class="font-weight-bold font-16 lh-sm">sustainability</a> <div class="font-serif mt-10 font-14"> Sustainability, the long-term viability of a community, set of social institutions, or societal practice. In general, sustainability is understood as a form of intergenerational ethics in which the environmental... </div> </div> </div> </div> </div> <div class="p-10 d-inline-flex js-pin col-100 col-sm-33 col-md-25 "> <div class="card text-normal col-100 "> <div class="card-media position-relative"> <a href="https://www.britannica.com/topic/environmental-law" style="--aspect-ratio: 16/9"> <img loading="lazy" src="https://cdn.britannica.com/mendel-resources/3-130/images/shared/default3.png?v=3.130.14" class="default col-100" /> </a> </div> <div class="col"> <div class="card-body text-hyphenate"> <a href="https://www.britannica.com/topic/environmental-law" class="font-weight-bold font-16 lh-sm">environmental law</a> <div class="font-serif mt-10 font-14"> Environmental law, principles, policies, directives, and regulations enacted and enforced by local, national, or international entities to regulate human treatment of the nonhuman world. 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