Cultivating the Seeds of Knowledge:
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Get Involved with the Encyclopedia of EarthLast Updated on 2014-03-09 17:39:06We are looking for authors who embrace the Encyclopedia of Earth quality standards, and who are willing to work under your real name in a dynamic, collaborative environment. We are expanding content in the physical and natural sciences, as well as associated fields of history, geography, environmental policy and allied engineering disciplines.
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California coastal sage and chaparralLast Updated on 2014-03-06 18:01:11
The California coastal sage and chaparral ecoregion, located along the southern and central coast of California, has extremely high levels of species diversity and endemism. The coastal sage scrub is an endangered ecosystem that contains a number of endangered species. The California Gnatcatcher is currently being used as an umbrella species to protect the endemic flora and fauna of this region from urban development. The region is listed as an Endemic Bird Area with a large number of endemic scrub species. Generally located on high value coastal zone real estate and threatened by land development, the ecoregion represents the struggle between ecological preservation and human development.
The California coastal sage and chaparral encompasses coastal terraces, plains, and foothills along the Pacific coast of northwestern Mexico and southern California, USA. The Santa Rosa Mountains... More »
Energy qualityLast Updated on 2014-03-06 16:45:22
Energy quality refers to differences in the ability of a unit of energy to produce goods and services for people. The usefulness of an energy system is determined by a complex combination of physical, technical, economic, and social attributes. These include gravimetric and volumetric energy density, power density, emissions, cost and efficiency of conversion, financial risk, amenability to storage, risk to human health, and ease of transport. No single metric of an energy system captures all such attributes. It stands to reason, therefore, that a comprehensive and balanced comparison of energy technologies should employ a range of metrics, with their strengths and weaknesses duly noted.
The most common way to measure energy is by heat content because all forms of energy can be completely converted to heat (Btus, joules, calories, kilowatt-hours). The aggregation of... More »
Palouse grasslandsLast Updated on 2014-03-06 15:18:43The Palouse grasslands ecoregion extends over eastern Washington, northwestern Idaho and northeastern Oregon. Grasslands and savannas once covered extensive areas of the inter-mountain west, from southwest Canada into western Montana in the USA. Today, areas like the great Palouse prairie of eastern are virtually eliminated as natural areas due to conversion to rangeland. The Palouse, formerly a vast expanse of native wheatgrasses (Agropyron spp), Idaho Fescue (Festuca idahoensis), and other grasses, has been plowed and converted to wheat fields or is covered by Drooping Brome (Bromus tectorum) and other alien plant species.
The Palouse lies in the rain shadow of the Cascades and has a generally semiarid climate. This climate is similar to that of the annual grasslands of California, yet the Palouse historically resembled the mixed-grass vegetation of the Central grasslands,... More »
Beringia upland tundraLast Updated on 2014-03-06 15:01:09
The Beringia Upland Tundra consists of three disjunct areas on the Bering Sea coast of Alaska, one comprised of the upland and mountainous areas of Seward Peninsula, one corresponding to the hills and mountains of the Ahklun and Kilbuck mountain ranges in southwest Alaska, and one of much smaller extent on the western half of St. Lawrence Island in the northern Bering Sea. These areas are similar in their varied terrain and elevation, and corresponding variety of vegetation, habitats, and communities. The ecoregion consists of steep, jagged mountain ranges set among large areas of rolling hills, broad valleys, and lowlands. Elevation ranges from sea level to 500 meters (m) in the hilly uplands to over 1,500 m in the tallest ranges. Plant communities respond to these differences in topography and accompanying drainage. Low-lying, poorly drained areas support wet graminoid... More »
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