River ecosystems are flowing waters that drain the landscape, and include the biotic (living) interactions amongst plants, animals and micro-organisms, as well as abiotic (nonliving) physical and chemical interactions of its many parts. River ecosystems are part of larger watershed networks or catchments, where smaller headwater streams drain into mid-size streams, which progressively drain into larger river networks. The major zones in river ecosystems are determined by the river bed's gradient or by the velocity of the current. Faster moving turbulent water typically contains greater concentrations of dissolved oxygen, which supports greater biodiversity than the slow-moving water of pools. These distinctions form the basis for the division of rivers into upland and lowland rivers.

The food base of streams within riparian forests is mostly derived from the trees, but wider streams and those that lack a canopy derive the majority of their food base from algae. Anadromous fish are also an important source of nutrients. Environmental threats to rivers include loss of water, dams, chemical pollution and introduced species. A dam produces negative effects that continue down the watershed. The most important negative effects are the reduction of spring flooding, which damages wetlands, and the retention of sediment, which leads to the loss of deltaic wetlands. (Full article...)

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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.

The role that a keystone species plays in its ecosystem is analogous to the role of a keystone in an arch. While the keystone is under the least pressure of any of the stones in an arch, the arch still collapses without it. Similarly, an ecosystem may experience a dramatic shift if a keystone species is removed, even though that species was a small part of the ecosystem by measures of biomass or productivity.

It became a popular concept in conservation biology, alongside flagship and umbrella species. Although the concept is valued as a descriptor for particularly strong inter-species interactions, and has allowed easier communication between ecologists and conservation policy-makers, it has been criticized for oversimplifying complex ecological systems. (Full article...)

John Stanley Beard (15 February 1916 – 17 February 2011) was a British-born forester and ecologist who resided in Australia. Beard studied at the University of Oxford where he completed his doctoral thesis on tropical forestry.

While working with the Forestry Division in Trinidad and Tobago during the 1940s, Beard developed a system of forest classification for Tropical America and described the forests of Trinidad, Tobago, and the Lesser Antilles; these descriptions remain standard references on the topics. (Full article...)

• ... that the British political theorist Chris Armstrong has called for a "blue new deal" to secure ecological resilience for the ocean and a just blue economy?
• ... that wampum artist Elizabeth James-Perry also works on ecological restoration projects, including the reintroduction of native plant life?
• ... that Kühkopf-Knoblochsaue is a large Naturschutzgebiet in Hesse, Germany, protecting the ecology of the floodplains where the Rhine formerly meandered?
• ... that ancient Roman gynecologists believed that menstrual blood could be used to drive dogs insane?
• ... that scientist Adelaida K. Semesi was known as "mama mangroves" due to her specialist knowledge of their ecology?
• ... that Enriqueta Medellín, a Mexican surgeon, has an ecological center and environmental prize named after her in the state of Aguascalientes?

“	The two most abundant forms of power on earth are solar and wind, and they're getting cheaper and cheaper…	”
	— Ed Begley Jr.

More selected quotes

• April 23: European Union to reduce carbon emissions by 55% of 1990 levels by 2030
• November 27: Wikinews interviews Craig Farquharson, Liberal Democrat candidate for 2020 Groom by-election
• November 27: Wikinews interviews Sandra Jephcott, Sustainable Australia candidate for 2020 Groom by-election
• December 14: Greta Thunberg named 2019 Time Person of the Year
• November 23: Researchers break down deaths due to power plant pollution in the United States
• November 21: Slippery business: Materials scientists invent new coating for self-cleaning, water-efficient toilets
• October 19: Northern Arapaho Tribe welcomes buffalo herd in Wyoming, United States
• October 12: Scientists describe how 'upside-down rivers' of warm water break Antarctica's ice shelf
• October 5: Voracious fish defend coral reefs against warming, say scientists
• September 8: Scientists report skyrocketing phytoplankton population in aftermath of Kīlauea eruption

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• November 5, 2009: "New ocean forming in African desert."

Frontiers in Ecology and the Environment is a peer-reviewed scientific journal. It is published ten times per year by the Ecological Society of America and is its official journal. Its focus is on present day concerns pertaining to ecological and environmental issues. (Full article...)