Encyclopedia of Earth
Encyclopedia of Earth: Geology: Silurian
Article covering the Silurian Period, which lasted from 443 million to 417 million years ago. It covers the subdivisions of this Period, some life forms preserved in the fossil record, geology, and climate. (Published: January 22, 2010)
Encyclopedia of Earth
Encyclopedia of Earth: Silicon
Information about the element, Silicon, atomic number 14. Covers physical properties, atomic properties, how abundant it is on the Earth, and details about health-related regulations. Also discusses sources of Silicon, and its many...
Encyclopedia of Earth
Encyclopedia of Earth: Scandium
Information about the element, Scandium, atomic number 21. Covers physical properties, atomic properties, how abundant it is on the Earth and where it is found, and details about any impact on human health.
Encyclopedia of Earth
Encyclopedia of Earth: Rubidium
Information about the element, Rubidium, atomic number 37. Covers physical properties, atomic properties, how abundant it is on the Earth, and details about health-related regulations.
Encyclopedia of Earth
Encyclopedia of Earth: Rhenium
Information about the metallic element, Rhenium, atomic number 75. Covers its physical and atomic properties, how abundant it is on the Earth, sources, uses, and potential substitutes.
Encyclopedia of Earth
Encyclopedia of Earth: Botany: Respiration
The process of respiration in plants, humans, and animals is discussed, along with diseases that can affect respiration. (Published: November 16, 2011)
Encyclopedia of Earth
Encyclopedia of Earth: Entomology: Insect Repellent
Information on insect repellents and how to use them safely. Includes links to additional resources. (Published: July 18, 2012)
Encyclopedia of Earth
Encyclopedia of Earth: Arctic Climate Impact Assessment
An extensive research report on climate change in the Arctic and the impact this is having on the environment, flora and fauna, and indigenous peoples. (Updated: December 20, 2010)
Encyclopedia of Earth
Encyclopedia of Earth: Rapid Changes in Glaciers and Ice Sheets
The world's glaciers and ice sheets are melting according to this extensive report. It makes recommendations on how to monitor this situation, explains what we know about the past when there was much less ice in the world, describes what...
Encyclopedia of Earth
Encyclopedia of Earth: Radon
Information about the radioactive element, Radon, atomic number 86. Covers physical properties, atomic properties, how abundant it is on the Earth, details about its impact on human health, and about how it can be monitored.
Encyclopedia of Earth
Encyclopedia of Earth: Radium
Information about the radioactive element, Radium, atomic number 88. Covers physical and atomic properties, how abundant it is on the Earth, and permissible exposure limits.
Encyclopedia of Earth
Encyclopedia of Earth: Proterozoic
Article describing the Proterozoic Eon, which lasted from 2.5 billion to 543 million years ago. It covers the subdivisions of the Proterozoic Eon, geology, Earth's atmosphere at the time, climate, and life forms. (Published: July 26, 2010)
Encyclopedia of Earth
Encyclopedia of Earth: Predation
Defines the term predation, describes the types, and explains the roles predation plays in population management, in species diversity, and in natural selection. (Published: December 28, 2009)
Encyclopedia of Earth
Encyclopedia of Earth: Potassium
Basic information about the element Potassium, atomic number 19. Covers its history, physical and atomic properties, and how abundant it is on the Earth.
Encyclopedia of Earth
Encyclopedia of Earth: Botany: Pollination
Scientific article detailing what pollination is, types of pollination, animals (mainly insects) that facilitate pollination, ways pollination can take place, its evolution, pollination in agriculture, and threats to pollination....
Encyclopedia of Earth
Encyclopedia of Earth: Plutonium
Information about the element, Plutonium, atomic number 94. Covers physical properties, atomic properties, how abundant it is on the Earth, and details about health-related regulations. Discusses reactor- and weapons-grade plutonium, and...
Encyclopedia of Earth
Encyclopedia of Earth: Geology: Pliocene
Article describing the Pliocene Epoch, which lasted from 5.3 million to 1.8 million years ago, and was part of the Cenozoic Era. It covers subdivisions of the Pliocene, geology, and climate. (Published: January 20, 2010)
Encyclopedia of Earth
Encyclopedia of Earth: Evolutionary Biology: Pleistocene
Article describing the Pleistocene Epoch, which lasted from 1.8 million to about 10,000 years ago. It discusses species that lived then (e.g., the mammoth), and the climate changes that took place at that time. (Published: May 8, 2010)
Encyclopedia of Earth
Encyclopedia of Earth: Platinum
Information about the element, Platinum, atomic number 78. Covers its physical and atomic properties, how abundant it is on the Earth, sources, uses, potential substitutes, and permissible exposure limits.
Encyclopedia of Earth
Encyclopedia of Earth: Botany: Pine
Article on pine tree. Covers classification, physical features, ecology, and ways pine is used by humans. (Published: May 31, 2012)
Encyclopedia of Earth
Encyclopedia of Earth: Photovoltaics
Article explaining what photovoltaic cells are, their role in solar energy, how they work, how electricity is produced, and applications of this technology. (Published: April 24, 2010)
Encyclopedia of Earth
Encyclopedia of Earth: Biogeochemistry: Phosphorus Cycle
Article explaining what the phosphorus cycle is, where it occurs, its place in the biotic world, and the environmental impact of human activities on the phosphorus cycle. (Published: October 8, 2009)
Encyclopedia of Earth
Encyclopedia of Earth: Phosphorus
Information about the element, Phosphorus, atomic number 15. Covers physical and atomic properties, the phosphorus cycle, phosphorus chemistry, and how exposure to white phosphorus affects human health.
Encyclopedia of Earth
Encyclopedia of Earth: Physics & Chemistry: Phosphate
Discusses what phosphates are, their role in the phosphorous cycle, where they occur in the natural world, their chemistry, and the impact of the use of phosphate fertilizers in agriculture.