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Sporobolus Cryptandrus
Sand dropseed ''(Sporobolus cryptandrus)'' is a species of grass in the family Poaceae. It is native to North America, where it is widespread in southern Canada, most of the United States, and northern Mexico. Description ''Sporobolus cryptandrus'' is a perennial bunchgrass that forms loose tufts of erect to decumbent stems, which can grow up to one meter in length. The stem bases are thickened but remain non-woody. The leaves are rough-haired along the margins, reaching up to 26 centimeters (10 in) in length, and some emerge perpendicularly from the stem. Its inflorescence is initially dense and narrow, eventually spreading out with age, and may be partly sheathed within the uppermost leaf. The species produces a large number of small seeds—each inflorescence can bear up to 10,000—which enhances its ability to colonize new areas and establish a persistent presence in the seed bank. These tiny seeds, approximately 1 mm in size, are often sticky when wet, which may facilitate ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Alzada, Montana
Alzada (also known as Stoneville and Telegraph Point) is a census-designated place in southern Carter County, Montana, United States. As of the 2010 census it had a population of 29. It is located at the intersection of U.S. Route 212 with Montana Secondary Highways 323 and 326, near the Wyoming and South Dakota borders. The Little Missouri River flows northwards to the west of the community. Alzada is in the Mountain Time Zone. History Alzada was first established in 1878, by 9th U.S. Infantry soldiers as Camp Devin, on the Deadwood, Dakota Territory to Fort Keogh, Montana Territory telegraph line. It was called the Little Missouri River Telegraph Station, and manned by soldiers of the 7th U.S. Cavalry. Then it was named Stoneville, after the local bartender Lou Stone. It served as a stagecoach stop between Deadwood and Miles City, Montana. It was the site of a gun battle in 1884 between local authorities and rustlers known as the Axleby gang. The town's name was chang ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Kiskunság
Kiskunság ("Little Cumania", ) is a historical and geographical region in Hungary situated in the current between Kalocsa and Szeged. Its territory is 2,423 km2. Like other historical European regions called Cumania, it is named for the Cumans (), a historically very significant nomadic tribe. Geography Its most defining feature is the sand dunes created by the flat area's windy nature, and bigger dunes being created by deposits of and the old path of the Danube and Tisza The Tisza, Tysa or Tisa (see below) is one of the major rivers of Central and Eastern Europe. It was once called "the most Hungarian river" because it used to flow entirely within the Kingdom of Hungary. Today, it crosses several national bo .... See also * Kunság (Cumania) * Nagykunság (Greater Cumania) * Kiskunság National Park References Historical regions in Hungary Geography of Hungary Biosphere reserves of Hungary Historical regions in the Kingdom of Hungary Cumans ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Invasive Species
An invasive species is an introduced species that harms its new environment. Invasive species adversely affect habitats and bioregions, causing ecological, environmental, and/or economic damage. The term can also be used for native species that become harmful to their native environment after human alterations to its food web. Since the 20th century, invasive species have become serious economic, social, and environmental threats worldwide. Invasion of long-established ecosystems by organisms is a natural phenomenon, but human-facilitated introductions have greatly increased the rate, scale, and geographic range of invasion. For millennia, humans have served as both accidental and deliberate dispersal agents, beginning with their earliest migrations, accelerating in the Age of Discovery, and accelerating again with the spread of international trade. Notable invasive plant species include the kudzu vine, giant hogweed (''Heracleum mantegazzianum''), Japanese knotw ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Species Composition
Relative species abundance is a component of biodiversity and is a measure of how common or rare a species is relative to other species in a defined location or community.Hubbell, S. P. 2001. ''The unified neutral theory of biodiversity and biogeography''. Princeton University Press, Princeton, N.J. Relative abundance is the percent composition of an organism of a particular kind relative to the total number of organisms in the area. Relative species abundance (ecology), abundances tend to conform to specific patterns that are among the best-known and most-studied patterns in macroecology. Different populations in a community exist in relative proportions; this idea is known as relative abundance. Introduction Relative species abundance Relative species abundance and species richness describe key elements of biodiversity. Relative species abundance refers to how common or rare a species is relative to other species in a given location or community.McGill, B. J., Etienne R. S., Gra ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Species Richness
Species richness is the number of different species represented in an community (ecology), ecological community, landscape or region. Species richness is simply a count of species, and it does not take into account the Abundance (ecology), abundances of the species or their Relative species abundance, relative abundance distributions. Species richness is sometimes considered synonymous with species diversity, but the formal metric species diversity takes into account both species richness and species evenness. Sampling considerations Depending on the purposes of quantifying species richness, the individuals can be Forest inventory#Simple random sampling, selected in different ways. They can be, for example, trees found in an forest inventory, inventory plot, birds observed from a monitoring point, or beetles collected in a pitfall trap. Once the set of individuals has been defined, its species richness can be exactly quantified, provided the species-level Taxonomy (biology), taxo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Soil Seed Bank
The soil seed bank is the natural storage of seeds, often dormant, within the soil of most ecosystems. The study of soil seed banks started in 1859 when Charles Darwin observed the emergence of seedlings using soil samples from the bottom of a lake. The first scientific paper on the subject was published in 1882 and reported on the occurrence of seeds at different soil depths. Weed seed banks have been studied intensely in agricultural science because of their important economic impacts; other fields interested in soil seed banks include forest regeneration and restoration ecology. Henry David Thoreau wrote that the contemporary popular belief explaining the succession of a logged forest, specifically to trees of a dissimilar species to the trees cut down, was that seeds either spontaneously generated in the soil, or sprouted after lying dormant for centuries. However, he dismissed this idea, noting that heavy nuts unsuited for distribution by wind were distributed instead by an ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mowing
A mower is a person or machine that cuts (mows) grass or other plants that grow on the ground. Usually mowing is distinguished from reaping, which uses similar implements, but is the traditional term for harvesting grain crops, e.g. with reapers and combines. A smaller mower used for lawns and sports grounds (playing fields) is called a ''lawn mower'' or ''grounds mower'', which is often self-powered, or may also be small enough to be pushed by the operator. Grounds mowers have reel or rotary cutters. Larger mowers or '' mower-conditioners'' are mainly used to cut grass (or other crops) for hay or silage and often place the cut material into rows, which are referred to as ''windrows''. '' Swathers'' (or ''windrowers'') are also used to cut grass (and grain crops). Prior to the invention and adoption of mechanized mowers, (and today in places where use a mower is impractical or uneconomical), grass and grain crops were cut by hand using scythes or sickles. Mower configuratio ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Central Europe
Central Europe is a geographical region of Europe between Eastern Europe, Eastern, Southern Europe, Southern, Western Europe, Western and Northern Europe, Northern Europe. Central Europe is known for its cultural diversity; however, countries in this region also share some historical and cultural similarities. The region is variously defined, but it’s minimum definition could be considered of consisting of Austria, Bosnia and Herzegovina, Croatia, the Czech Republic, eastern France, Germany, Liechtenstein, Luxembourg, Poland, Slovakia, Slovenia and Switzerland. But also the Baltic States, the Alsace in north-east France, and South Tyrol, northern Belluno , and Friuli-Venezia Giulia in north-east Italy are culturally usually considered to be part of Central Europe. From the early 16th century until the early 18th century, parts of Croatia and Hungary were ruled by the Ottoman Empire. During the 17th century, the empire also occupied southern parts of present-day Slovakia. During ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Soil Seed Bank
The soil seed bank is the natural storage of seeds, often dormant, within the soil of most ecosystems. The study of soil seed banks started in 1859 when Charles Darwin observed the emergence of seedlings using soil samples from the bottom of a lake. The first scientific paper on the subject was published in 1882 and reported on the occurrence of seeds at different soil depths. Weed seed banks have been studied intensely in agricultural science because of their important economic impacts; other fields interested in soil seed banks include forest regeneration and restoration ecology. Henry David Thoreau wrote that the contemporary popular belief explaining the succession of a logged forest, specifically to trees of a dissimilar species to the trees cut down, was that seeds either spontaneously generated in the soil, or sprouted after lying dormant for centuries. However, he dismissed this idea, noting that heavy nuts unsuited for distribution by wind were distributed instead by an ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Photosynthesis
Photosynthesis ( ) is a system of biological processes by which photosynthetic organisms, such as most plants, algae, and cyanobacteria, convert light energy, typically from sunlight, into the chemical energy necessary to fuel their metabolism. ''Photosynthesis'' usually refers to oxygenic photosynthesis, a process that produces oxygen. Photosynthetic organisms store the chemical energy so produced within intracellular organic compounds (compounds containing carbon) like sugars, glycogen, cellulose and starches. To use this stored chemical energy, an organism's cells metabolize the organic compounds through cellular respiration. Photosynthesis plays a critical role in producing and maintaining the oxygen content of the Earth's atmosphere, and it supplies most of the biological energy necessary for complex life on Earth. Some bacteria also perform anoxygenic photosynthesis, which uses bacteriochlorophyll to split hydrogen sulfide as a reductant instead of water, p ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
C4 Carbon Fixation
carbon fixation or the Hatch–Slack pathway is one of three known photosynthetic processes of carbon fixation in plants. It owes the names to the 1960s discovery by Marshall Davidson Hatch and Charles Roger Slack. fixation is an addition to the ancestral and more common carbon fixation. The main carboxylating enzyme in photosynthesis is called RuBisCO, which catalyses two distinct reactions using either (carboxylation) or oxygen (oxygenation) as a substrate. RuBisCO oxygenation gives rise to phosphoglycolate, which is toxic and requires the expenditure of energy to recycle through photorespiration. photosynthesis reduces photorespiration by concentrating around RuBisCO. To enable RuBisCO to work in a cellular environment where there is a lot of carbon dioxide and very little oxygen, leaves generally contain two partially isolated compartments called mesophyll cells and bundle-sheath cells. is initially fixed in the mesophyll cells in a reaction catalysed by th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Black-tailed Prairie Dog
The black-tailed prairie dog (''Cynomys ludovicianus'') is a rodent of the family Sciuridae (the squirrels) found in the Great Plains of North America from about the United States–Canada border to the United States–Mexico border. Unlike some other prairie dogs, these animals do not truly hibernate. The black-tailed prairie dog can be seen above ground in midwinter. A black-tailed prairie dog town in Texas was reported to cover and included 400,000,000 individuals. Prior to habitat destruction, the species may have been the most abundant prairie dog in central North America. It was one of two prairie dogs described by the Lewis and Clark Expedition in the journals and diaries of their expedition. Description Black-tailed prairie dogs are generally tan in color, with lighter-colored bellies. They may have color variation in their pelt, such as dark fur on their back in black and brown tones. Their tails have black tips, from which their name is derived. Adults can weigh from ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
