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The application of biotechnological techniques utilizing fungi for agricultural purposes. Fungal biotechnology is applied in agriculture to promote plant vigor, to increase yields, and to reduce impacts of plant diseases, weeds, or invertebrate…

The expression of a heritable trait in both the homozygous and heterozygous conditions. Genetic dominance (Fig. 1) is a cornerstone of the basic laws of biological inheritance (also known as Mendelian inheritance or Mendelism). In particular,…

Photosynthesis is a key natural process utilized by plants and is necessary for proper plant growth. Specifically, photosynthesis uses light to manufacture chemical compounds, including organic compounds—primarily carbohydrates—that are derived from…

Plants that have altered genetic material (DNA) through recombinant DNA (rDNA) manipulation. Genetic engineering of plants allows for very specific genetic changes to be made to a plant's deoxyribonucleic acid (DNA), as opposed to the random…

Commercially grown plants that have altered genetic material through artificial recombinant manipulation. Genetic modification is the latest scientific tool for developing improved crop varieties. Such genetically modified (GM) crops can help to…

The discipline of Earth science that investigates the chemical composition of the Earth, other planets, and the universe as a whole, as well as the chemical processes that occur within them. Geochemistry is important because basic knowledge about…

Computer-based technologies for storing, manipulating, and analyzing geographically referenced information. Attribute information and spatial information are integrated in geographic information systems (GIS) through the notion of a data layer,…

The science of the Earth. The study of the Earth's materials and of the processes that shape them is known as physical geology. Historical geology is the record of past events. Earth Earth sciencesEnergy from two sources continually produces changes…

The study of landforms, including the description, classification, origin, development, and history of planetary surface features. Emphasis is placed on the interpretation of the erosional and depositional features of the Earth's surface. However,…

Thermal or electrical power produced from the thermal energy contained in the Earth (geothermal energy). Use of geothermal energy is based thermodynamically on the temperature difference between a mass of subsurface rock and water and a mass of…

Researchers surveying ice loss from 650 glaciers across a 2000-kilometer (1240-mile) west-to-east expanse of the Himalayan Mountains reported in the journal Science Advances (June 2019) significant melting caused by global climate change over the…

A broad field encompassing all aspects of the study of ice. Many glaciologists focus their attention on glaciers, the largest ice masses on Earth, but glaciology also includes the study of ice that forms on rivers, lakes, and the sea; ice in the…

Significant and persistent changes in the state of Earth’s climate. Earth's past climates, or paleoclimates, have alternated between ice ages and periods warmer than today over relatively long time scales (millions to tens of millions of years)…

The rise in the surface temperature of the Earth. Global warming is one of the names given to the systematic increase of globally averaged surface temperature that has been measured since the mid-nineteenth century. There is abundant evidence that…

All freshwater comes from precipitation over land, which is distributed on Earth as blue and green water. Blue water—that is, surface and groundwater—is stored as freshwater in lakes, streams, ice, and snow, as well as below ground. Green water is…

A glass- or plastic-enclosed structure that is used to grow plants under protected conditions. Greenhouses (also known as glasshouses) are transparent, enclosed, climate-controlled structures (Fig. 1) in which young, tender, or out-of-season plants…

A mineral with the chemical composition MnWO4. Hübnerite (sometimes spelled huebnerite) is the manganese member of the wolframite solid-solution series. It commonly contains small amounts of iron. It occurs in monoclinic, short, prismatic crystals.…

A tropical cyclone with maximum sustained winds that reach or exceed a threshold of 119 km/h (74 mi/h). In the western North Pacific Ocean such a storm is known as a typhoon and in other parts as a severe tropical cyclone. Many tropical cyclones do…

Accelerating fluxes and stores of water in the atmosphere, oceans, and land regions because of global warming. Figure 1 shows the primary hydrologic cycle compartments and fluxes. The total volume of water in the Earth system is approximately 1.36 ×…

A large mass of glacial ice broken off and drifted from parent glaciers or ice shelves along polar seas. Icebergs are distinguished from polar pack ice, which is sea ice, and from frozen seawater, whose rafted or hummocked fragments may resemble…

Researchers Chi Ma of Caltech and Alan Rubin of the University of California at Los Angeles reported in the journal American Mineralogist (September 2019) the discovery in a meteorite of the first natural occurrence of the iron-carbide mineral…

Earth’s surface temperature is warming, and the Arctic region is warming even faster. Yet winters in the mid-latitudes of Asia, Europe, and the United States have been colder than average, thanks to blasts of record-breaking frigid air caused by…

After reports that June 2019 was the warmest June on record, July 2019 followed with the dubious distinction that it was the warmest month since atmospheric temperature record-keeping began in 1880, according to the U.S. National Oceanic and…

Researchers at Duke University in North Carolina (United States) have developed a test for distinguishing lead isotopes found in coal fly ash from lead isotopes found in other lead-containing sources, such as paint. Fly ash is a fine particulate…