abiotic factors in a grassland ecosystem
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Grasslands (also called greenswards) are areas where the vegetation is dominated by grasses (Poaceae) and other herbaceous (non-woody) plants (forbs). However, sedge (Cyperaceae) and rush (Juncaceae) families can also be found. Grasslands occur naturally on all continents except Antarctica. In temperate latitudes, such as northwest Europe and the Great Plains and California in North America, native grasslands are dominated by perennial bunch grass species, whereas in warmer climates annual species form a greater component of the vegetation.
Grasslands are found in most ecological regions of the earth. For example there are five Terrestrial ecoregion classifications (subdivisions) of the Temperate grasslands, savannas, and shrublandsBiome ('Ecosystem'), which is one of eight Terrestrial ecozones of the Earth's surface.
Grassland vegetation can vary in height from very short, as in chalk where the vegetation may be less than 30|cm|abbr=on high, to quite tall, as in the case of North American tallgrass prairie, South American grasslands and African savanna. Woody plants, shrubs or trees, may occur on some grasslands - forming savannas, scrubby grassland or semi-wooded grassland, such as the African savannas or the Iberian dehesa. Such grasslands are sometimes referred to as wood-pasture or woodland.
Grasslands cover nearly fifty percent of the land surface of the continent of Africa. While grasslands in general support diverse wildlife, given the lack of hiding places for predators, the African Savanna regions support a much greater diversity in wildlife than do temperate grasslands.
The appearance of mountains in the western United States during the Miocene and Pliocene epochs, a period of some 25 million years, created a continental climate favorable to the evolution of grasslands. Existing forest biomes declined, and grasslands became much more widespread. Following the PleistoceneIce Ages, grasslands expanded in range in the hotter, drier climates, and began to become the dominant land feature worldwide.
As flowering plants, grasses grow in great concentrations in climates where annual rainfall ranges between 500|and|900|mm|abbr=on. The root systems of perennial grasses and forbs form complex mats that hold the soil in place. Mites, insect larvae, nematodes and earthworms inhabit deep soil, which can reach 6|m underground in undisturbed grasslands on the richest soils of the world. These invertebrates, along with symbiotic fungi, extend the root systems, break apart hard soil, enrich it with urea and other natural fertilizers, trap minerals and water and promote growth. Some types of fungi make the plants more resistant to insect and microbial attacks.
Natural grasslands primarily occur in regions that receive between 250|and|900|mm|abbr=on of rain per year, as compared with deserts, which receive less than 250|mm|abbr=on and tropical rainforests, which receive more than 2000|mm|abbr=on. Anthropogenic grasslands often occur in much higher rainfall zones, as high as 200|cm|abbr=on annual rainfall. Grassland can exist naturally in areas with higher rainfall when other factors prevent the growth of forests, such as in serpentine barrens, where minerals in the soil inhibit most plants from growing.
Average daily temperatures range between -20 and 30 Â°C. Temperate grasslands have warm summers and cold winters with rain or some snow.
Grassland biodiversity and conservation
Grasslands dominated by unsown wild-plant communities ("unimproved grasslands") can be called either natural or 'semi-natural' habitats. The majority of grasslands in temperate climates are 'semi-natural'. Although their plant communities are natural, their maintenance depends upon anthropogenic activities such as low-intensity farming, which maintains these grasslands through grazing and cutting regimes. These grasslands contain many species of wild plants - grasses, sedges, rushes and herbs - 25 or more speerican prairie grasslands or lowland wildflower meadows in the UK are now rare and their associated wild flora equally threatened. Associated with the wild-plant diversity of the "unimproved" grasslands is usually a rich invertebrate fauna; also there are many species of birds that are grassland "specialists", such as the snipe and the Great Bustard. Agriculturally improved grasslands, which dominate modern intensive agricultural landscapes, are usually poor in wild plant species due to the original diversity of plants having been destroyed by cultivation, the original wild-plant communities having been replaced by sown monocultures of cultivated varieties of grasses and clovers, such as Perennial ryegrass and White Clover. In many pa
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Answers:Biotic is referring to the biology or organisms present in a particular ecosystem. So it is all of the species present, whether plant or animal and both eukaryotic and prokaryotic organisms. Abiotic factors include all the non-living features of an ecosystem, Minerals, inorganic substances such as bio-limiting nutrients etc.
Answers:An "abiotic factor" denotes any inorganic, non-living substance or matter. So in a grassland, this can range include sunlight, water, soil, grass, etc.
Answers:Some abiotic factors are as simple as temperature, dirt, water, oxygen etc. It is pretty much anything that isn't living that you could find there.