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Rill
In hillslope geomorphology, a rill is a shallow channel (no more than a few inches/ decimeters deep) cut into soil by the erosive action of flowing surface water. Similar but smaller incised channels are known as microrills; larger incised channels are known as gullies. Artificial rills are channels constructed to carry a water supply from a distant water source. In landscape or garden design, constructed rills are an aesthetic water feature. Rills created by erosion Rills are narrow and shallow channels which are eroded into unprotected soil by hillslope runoff. Since soil is regularly left bare during agricultural operations, rills may form on farmland during these vulnerable periods. Rills may also form when bare soil is left exposed following deforestation, or during construction activities. Rills are fairly easily visible when first incised, so they are often the first indication of an ongoing erosion problem. Unless soil conservation measures are put into place ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Rill Network From Tyrone, Ireland
In hillslope geomorphology, a rill is a shallow channel (no more than a few inches/decimeters deep) cut into soil by the erosive action of flowing surface water. Similar but smaller incised channels are known as microrills; larger incised channels are known as gullies. Artificial rills are channels constructed to carry a water supply from a distant water source. In landscape or garden design, constructed rills are an aesthetic water feature. Rills created by erosion Rills are narrow and shallow channels which are eroded into unprotected soil by hillslope runoff. Since soil is regularly left bare during agricultural operations, rills may form on farmland during these vulnerable periods. Rills may also form when bare soil is left exposed following deforestation, or during construction activities. Rills are fairly easily visible when first incised, so they are often the first indication of an ongoing erosion problem. Unless soil conservation measures are put into place, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Construction
Construction is a general term meaning the art and science of forming Physical object, objects, systems, or organizations."Construction" def. 1.a. 1.b. and 1.c. ''Oxford English Dictionary'' Second Edition on CD-ROM (v. 4.0) Oxford University Press 2009 It comes from the Latin word ''constructio'' (from ''com-'' "together" and ''struere'' "to pile up") and Old French ''construction''. To 'construct' is a verb: the act of building, and the noun is construction: how something is built or the nature of its structure. In its most widely used context, construction covers the processes involved in delivering buildings, infrastructure, industrial facilities, and associated activities through to the end of their life. It typically starts with planning, financing, and design that continues until the asset is built and ready for use. Construction also covers repairs and maintenance work, any works to expand, extend and improve the asset, and its eventual demolition, dismantling or wikt:de ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Erosion
Erosion is the action of surface processes (such as water flow or wind) that removes soil, rock, or dissolved material from one location on the Earth's crust, and then transports it to another location where it is deposited. Erosion is distinct from weathering which involves no movement. Removal of rock or soil as clastic sediment is referred to as ''physical'' or ''mechanical'' erosion; this contrasts with ''chemical'' erosion, where soil or rock material is removed from an area by dissolution. Eroded sediment or solutes may be transported just a few millimetres, or for thousands of kilometres. Agents of erosion include rainfall; bedrock wear in rivers; coastal erosion by the sea and waves; glacial plucking, abrasion, and scour; areal flooding; wind abrasion; groundwater processes; and mass movement processes in steep landscapes like landslides and debris flows. The rates at which such processes act control how fast a surface is eroded. Typically, physical ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Aqueduct (water Supply)
An aqueduct is a watercourse constructed to carry water from a source to a distribution point far away. In modern engineering, the term ''aqueduct'' is used for any system of pipes, ditches, canals, tunnels, and other structures used for this purpose. The term ''aqueduct'' also often refers specifically to a bridge carrying an artificial watercourse. Aqueducts were used in ancient Greece, ancient Egypt, and ancient Rome. The simplest aqueducts are small ditches cut into the earth. Much larger channels may be used in modern aqueducts. Aqueducts sometimes run for some or all of their path through tunnels constructed underground. Modern aqueducts may also use pipelines. Historically, agricultural societies have constructed aqueducts to irrigate crops and supply large cities with drinking water. Etymology The word ''aqueduct'' is derived from the Latin words (''water'') and (''led'' or ''guided''). Ancient aqueducts Although particularly associated with the Romans, aqueducts we ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Overland Flow
Surface runoff (also known as overland flow) is the flow of water occurring on the ground surface when excess rainwater, stormwater, meltwater, or other sources, can no longer sufficiently rapidly infiltrate in the soil. This can occur when the soil is saturated by water to its full capacity, and the rain arrives more quickly than the soil can absorb it. Surface runoff often occurs because impervious areas (such as roofs and pavement) do not allow water to soak into the ground. Furthermore, runoff can occur either through natural or man-made processes. Surface runoff is a major component of the water cycle. It is the primary agent of soil erosion by water. The land area producing runoff that drains to a common point is called a drainage basin. Runoff that occurs on the ground surface before reaching a channel can be a nonpoint source of pollution, as it can carry man-made contaminants or natural forms of pollution (such as rotting leaves). Man-made contaminants in runoff in ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Surface Runoff
Surface runoff (also known as overland flow) is the flow of water occurring on the ground surface when excess rainwater, stormwater, meltwater, or other sources, can no longer sufficiently rapidly infiltrate in the soil. This can occur when the soil is saturated by water to its full capacity, and the rain arrives more quickly than the soil can absorb it. Surface runoff often occurs because impervious areas (such as roofs and pavement) do not allow water to soak into the ground. Furthermore, runoff can occur either through natural or man-made processes. Surface runoff is a major component of the water cycle. It is the primary agent of soil erosion by water. The land area producing runoff that drains to a common point is called a drainage basin. Runoff that occurs on the ground surface before reaching a channel can be a nonpoint source of pollution, as it can carry man-made contaminants or natural forms of pollution (such as rotting leaves). Man-made contaminants in runoff i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Aesthetic
Aesthetics, or esthetics, is a branch of philosophy that deals with the nature of beauty and taste, as well as the philosophy of art (its own area of philosophy that comes out of aesthetics). It examines aesthetic values, often expressed through judgments of taste. Aesthetics covers both natural and artificial sources of experiences and how we form a judgment about those sources. It considers what happens in our minds when we engage with objects or environments such as viewing visual art, listening to music, reading poetry, experiencing a play, watching a fashion show, movie, sports or even exploring various aspects of nature. The philosophy of art specifically studies how artists imagine, create, and perform works of art, as well as how people use, enjoy, and criticize art. Aesthetics considers why people like some works of art and not others, as well as how art can affect moods or even our beliefs. Both aesthetics and the philosophy of art try to find answers for what exa ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Deforestation
Deforestation or forest clearance is the removal of a forest or stand of trees from land that is then land conversion, converted to non-forest use. Deforestation can involve conversion of forest land to farms, ranches, or urban area, urban use. The most concentrated deforestation occurs in tropical rainforests. About 31% of Earth's land surface is covered by forests at present. This is one-third less than the forest cover before the expansion of agriculture, a half of that loss occurring in the last century. Between 15 million to 18 million hectares of forest, an area the size of Bangladesh, are destroyed every year. On average 2,400 trees are cut down each minute. The Food and Agriculture Organization, Food and Agriculture Organization of the United Nations defines deforestation as the conversion of forest to other land uses (regardless of whether it is human-induced). "Deforestation" and "forest area net change" are not the same: the latter is the sum of all forest losses ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Limestone
Limestone ( calcium carbonate ) is a type of carbonate sedimentary rock which is the main source of the material lime. It is composed mostly of the minerals calcite and aragonite, which are different crystal forms of . Limestone forms when these minerals precipitate out of water containing dissolved calcium. This can take place through both biological and nonbiological processes, though biological processes, such as the accumulation of corals and shells in the sea, have likely been more important for the last 540 million years. Limestone often contains fossils which provide scientists with information on ancient environments and on the evolution of life. About 20% to 25% of sedimentary rock is carbonate rock, and most of this is limestone. The remaining carbonate rock is mostly dolomite, a closely related rock, which contains a high percentage of the mineral dolomite, . ''Magnesian limestone'' is an obsolete and poorly-defined term used variously for dolomite, for lime ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Semi-arid
A semi-arid climate, semi-desert climate, or steppe climate is a dry climate sub-type. It is located on regions that receive precipitation below potential evapotranspiration, but not as low as a desert climate. There are different kinds of semi-arid climates, depending on variables such as temperature, and they give rise to different biomes. Defining attributes of semi-arid climates A more precise definition is given by the Köppen climate classification, which treats steppe climates (''BSk'' and ''BSh'') as intermediates between desert climates (BW) and humid climates (A, C, D) in ecological characteristics and agricultural potential. Semi-arid climates tend to support short, thorny or scrubby vegetation and are usually dominated by either grasses or shrubs as it usually can't support forests. To determine if a location has a semi-arid climate, the precipitation threshold must first be determined. The method used to find the precipitation threshold (in millimeters): *multip ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
