Fauna ( pl. : faunae or faunas ) is all of the animal life present in a particular region or time. The corresponding terms for plants and fungi are flora and funga , respectively. Flora, fauna, funga and other forms of life are collectively referred to as biota . Zoologists and paleontologists use fauna to refer to a typical collection of animals found in a specific time or place, e.g. the " Sonoran Desert fauna" or the " Burgess Shale fauna". Paleontologists sometimes refer to a sequence of faunal stages , which is a series of rocks all containing similar fossils. The study of animals of a particular region is called faunistics .
22-596: Fauna comes from the name Fauna , a Roman goddess of earth and fertility, the Roman god Faunus , and the related forest spirits called Fauns . All three words are cognates of the name of the Greek god Pan , and panis is the Modern Greek equivalent of fauna (πανίς or rather πανίδα). Fauna is also the word for a book that catalogues the animals in such a manner. The term was first used by Carl Linnaeus from Sweden in
44-584: A 1 mm mesh also depends upon whether it is alive or dead at the time of sorting. Mesofauna are macroscopic soil animals such as arthropods or nematodes . Mesofauna are extremely diverse; considering just the springtails ( Collembola ), as of 1998, approximately 6,500 species had been identified. Microfauna are microscopic or very small animals (usually including protozoans and very small animals such as rotifers ). To qualify as microfauna, an organism must exhibit animal-like characteristics, as opposed to microflora , which are more plant-like. Stygofauna
66-452: A group of organisms by their size, larger than microfauna but smaller than macrofauna, rather than a taxonomic grouping. One environment for meiofauna is between grains of damp sand (see Mystacocarida ). In practice these are metazoan animals that can pass unharmed through a 0.5–1 mm mesh but will be retained by a 30–45 μm mesh, but the exact dimensions will vary from researcher to researcher. Whether an organism passes through
88-597: A lack of wings and longer appendages . Xenofauna , theoretically , are alien organisms that can be described as animal analogues . While no alien life forms, animal-like or otherwise, are known definitively, the concept of alien life remains a subject of great interest in fields like astronomy , astrobiology , biochemistry , evolutionary biology , science fiction , and philosophy . Other terms include avifauna , which means " bird fauna" and piscifauna (or ichthyofauna ), which means " fish fauna". fauna Too Many Requests If you report this error to
110-441: A permanent change in the water table in such regions. Most crops need a water table at a minimum depth. For some important food and fiber crops a classification was made because at shallower depths the crop suffers a yield decline. A water table close to the surface affects excavation, drainage, foundations, wells and leach fields (in areas without municipal water and sanitation), and more. When excavation occurs near enough to
132-481: Is an aquifer that occurs above the regional water table. This occurs when there is an impermeable layer of rock or sediment ( aquiclude ) or relatively impermeable layer ( aquitard ) above the main water table/aquifer but below the land surface. If a perched aquifer's flow intersects the surface, at a valley wall, for example, the water is discharged as a spring . On low-lying oceanic islands with porous soil, freshwater tends to collect in lenticular pools on top of
154-408: Is any fauna that lives in groundwater systems or aquifers, such as caves , fissures and vugs . Stygofauna and troglofauna are the two types of subterranean fauna (based on life-history). Both are associated with subterranean environments – stygofauna is associated with water, and troglofauna with caves and spaces above the water table . Stygofauna can live within freshwater aquifers and within
176-493: Is associated with caves and spaces above the water table and stygofauna with water. Troglofaunal species include spiders , insects , myriapods and others. Some troglofauna live permanently underground and cannot survive outside the cave environment. Troglofauna adaptations and characteristics include a heightened sense of hearing, touch and smell. Loss of under-used senses is apparent in the lack of pigmentation as well as eyesight in most troglofauna. Troglofauna insects may exhibit
198-443: Is referred to as the potentiometric surface , not the water table. The water table may vary due to seasonal changes such as precipitation and evapotranspiration . In undeveloped regions with permeable soils that receive sufficient amounts of precipitation, the water table typically slopes toward rivers that act to drain the groundwater away and release the pressure in the aquifer. Springs , rivers , lakes and oases occur when
220-519: The pore spaces of limestone , calcrete or laterite , whilst larger animals can be found in cave waters and wells. Stygofaunal animals, like troglofauna, are divided into three groups based on their life history - stygophiles, stygoxenes, and stygobites. Troglofauna are small cave -dwelling animals that have adapted to their dark surroundings. Troglofauna and stygofauna are the two types of subterranean fauna (based on life-history). Both are associated with subterranean environments – troglofauna
242-576: The Wikimedia System Administrators, please include the details below. Request from 172.68.168.150 via cp1114 cp1114, Varnish XID 910087786 Upstream caches: cp1114 int Error: 429, Too Many Requests at Thu, 28 Nov 2024 07:40:11 GMT Water table The water table is the upper surface of the zone of saturation . The zone of saturation is where the pores and fractures of the ground are saturated with groundwater , which may be fresh, saline, or brackish, depending on
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#1732779611818264-483: The aquifer. In areas with sufficient precipitation, water infiltrates through pore spaces in the soil, passing through the unsaturated zone. At increasing depths, water fills in more of the pore spaces in the soils, until a zone of saturation is reached. Below the water table, in the phreatic zone (zone of saturation), layers of permeable rock that yield groundwater are called aquifers . In less permeable soils, such as tight bedrock formations and historic lakebed deposits,
286-548: The bottom substratum of a water body, especially within the bottom-most oceanic sediments, the layer of small particles at the bottom of a body of water, rather than on its surface. Bacteria and microalgae may also live in the interstices of bottom sediments. In general, infaunal animals become progressively smaller and less abundant with increasing water depth and distance from shore, whereas bacteria show more constancy in abundance, tending toward one million cells per milliliter of interstitial seawater. Such creatures are found in
308-399: The denser seawater intruding from the sides of the islands. Such an island's freshwater lens, and thus the water table, rises and falls with the tides. In some regions, for example, Great Britain or California , winter precipitation is often higher than summer precipitation and so the groundwater storage is not fully recharged in summer. Consequently, the water table is lower during
330-482: The direction of groundwater flow typically has both a horizontal and a vertical component. The slope of the water table is known as the “hydraulic gradient”, which depends on the rate at which water is added to and removed from the aquifer and the permeability of the material. The water table does not always mimic the topography due to variations in the underlying geological structure (e.g., folded, faulted, fractured bedrock). A perched water table (or perched aquifer)
352-406: The fossil record and include lingulata , trilobites and worms . They made burrows in the sediment as protection and may also have fed upon detritus or the mat of microbes which tended to grow on the surface of the sediment. Today, a variety of organisms live in and disturb the sediment . The deepest burrowers are the ghost shrimps ( Thalassinidea ), which go as deep as 3 metres (10 ft) into
374-431: The locality. It can also be simply explained as the depth below which the ground is saturated. The water table is the surface where the water pressure head is equal to the atmospheric pressure (where gauge pressure = 0). It may be visualized as the "surface" of the subsurface materials that are saturated with groundwater in a given vicinity. The groundwater may be from precipitation or from groundwater flowing into
396-576: The sediment at the bottom of the ocean. Limnofauna refers to the animals that live in fresh water. Macrofauna are benthic or soil organisms which are retained on a 0.5 mm sieve. Studies in the deep sea define macrofauna as animals retained on a 0.3 mm sieve to account for the small size of many of the taxa. Megafauna are large animals of any particular region or time. For example, Australian megafauna . Meiofauna are small benthic invertebrates that live in both marine and freshwater environments . The term meiofauna loosely defines
418-433: The summer. This disparity between the level of the winter and summer water table is known as the "zone of intermittent saturation", wherein the water table will fluctuate in response to climatic conditions. Fossil water is groundwater that has remained in an aquifer for several millennia and occurs mainly in deserts . It is non-renewable by present-day rainfall due to its depth below the surface, and any extraction causes
440-465: The title of his 1745 work Fauna Suecica . Cryofauna refers to the animals that live in, or very close to, cold areas. Cryptofauna is the fauna that exists in protected or concealed microhabitats . Epifauna, also called epibenthos , are aquatic animals that live on the bottom substratum as opposed to within it, that is, the benthic fauna that live on top of the sediment surface at the seafloor. Infauna are benthic organisms that live within
462-413: The water table may be more difficult to define. “Water table” and “ water level ” are not synonymous. If a deeper aquifer has a lower permeable unit that confines the upward flow, then the water level in this aquifer may rise to a level that is greater or less than the elevation of the actual water table. The elevation of the water in this deeper well is dependent upon the pressure in the deeper aquifer and
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#1732779611818484-420: The water table reaches the surface. Groundwater entering rivers and lakes accounts for the base-flow water levels in water bodies. Within an aquifer, the water table is rarely horizontal, but reflects the surface relief due to the capillary effect ( capillary fringe ) in soils , sediments and other porous media . In the aquifer, groundwater flows from points of higher pressure to points of lower pressure, and
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