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Crop Yields
In agriculture, the yield is a measurement of the amount of a crop grown, or product such as wool, meat or milk produced, per unit area of land. The seed ratio is another way of calculating yields. Innovations, such as the use of fertilizer, the creation of better farming tools, new methods of farming and improved crop varieties, have improved yields. The higher the yield and more intensive use of the farmland, the higher the productivity and profitability of a farm; this increases the well-being of farming families. Surplus crops beyond the needs of subsistence agriculture can be sold or bartered. The more grain or fodder a farmer can produce, the more draft animals such as horses and oxen could be supported and harnessed for labour and production of manure. Increased crop yields also means fewer hands are needed on farm, freeing them for industry and commerce. This, in turn, led to the formation and growth of cities, which then translated into an increased demand for foodstuffs ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Agriculture
Agriculture or farming is the practice of cultivating plants and livestock. Agriculture was the key development in the rise of sedentary human civilization, whereby farming of domesticated species created food surpluses that enabled people to live in cities. The history of agriculture began thousands of years ago. After gathering wild grains beginning at least 105,000 years ago, nascent farmers began to plant them around 11,500 years ago. Sheep, goats, pigs and cattle were domesticated over 10,000 years ago. Plants were independently cultivated in at least 11 regions of the world. Industrial agriculture based on large-scale monoculture in the twentieth century came to dominate agricultural output, though about 2 billion people still depended on subsistence agriculture. The major agricultural products can be broadly grouped into foods, fibers, fuels, and raw materials (such as rubber). Food classes include cereals (grains), vegetables, fruits, cooking oils, meat, milk, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Harvest
Harvesting is the process of gathering a ripe crop from the fields. Reaping is the cutting of grain or pulse for harvest, typically using a scythe, sickle, or reaper. On smaller farms with minimal mechanization, harvesting is the most labor-intensive activity of the growing season. On large mechanized farms, harvesting uses the most expensive and sophisticated farm machinery, such as the combine harvester. Process automation has increased the efficiency of both the seeding and harvesting processes. Specialized harvesting equipment utilizing conveyor belts to mimic gentle gripping and mass-transport replaces the manual task of removing each seedling by hand. The term "harvesting" in general usage may include immediate postharvest handling, including cleaning, sorting, packing, and cooling. The completion of harvesting marks the end of the growing season, or the growing cycle for a particular crop, and the social importance of this event makes it the focus of seasonal celebrati ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Grain Yield Monitor
The combine grain yield monitor is a device coupled with other sensors to calculate and record the crop yield or grain yield as a modern-day combine harvester operates. Yield monitors are a part of the precision agriculture products available to producers today that provide producers with the tools to reduce costs, increase yields, and increase efficiency. The present day grain yield monitor is designed to measure the harvested grain mass flow, moisture content, and speed to determine total grain harvested. In most cases today this is coupled with global positioning system to record yield and other spatially variable information across a field. This allows for the creation of a grain yield map which provides information on spatial variability and supports management decisions for producers. Grain flow measurement Impact based mass flow measurement Grain mass flow is most commonly measured using a load cell with an impact plate attached to the load cell located at the to ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Agricultural Productivity
Agricultural productivity is measured as the ratio of agricultural outputs to inputs. While individual products are usually measured by weight, which is known as crop yield, varying products make measuring overall agricultural output difficult. Therefore, agricultural productivity is usually measured as the market value of the final output. This productivity can be compared to many different types of inputs such as labour or land. Such comparisons are called partial measures of productivity. Agricultural productivity may also be measured by what is termed total factor productivity (TFP). This method of calculating agricultural productivity compares an index of agricultural inputs to an index of outputs. This measure of agricultural productivity was established to remedy the shortcomings of the partial measures of productivity; notably that it is often hard to identify the factors cause them to change. Changes in TFP are usually attributed to technological improvements. Agri ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Actual Production History
In United States federal agricultural law, the terminology Actual Production History (APH) denotes a record of an agricultural producer’s crop yields over a multi-year period. Such records are used by the Federal Crop Insurance Corporation The Federal Crop Insurance Corporation (FCIC) is a wholly owned government corporation managed by the Risk Management Agency of the United States Department of Agriculture. FCIC manages the federal crop insurance program, which provides U.S. fa ... to determine “normal” production levels for a producer. The term "Actual Production History insurance" is used synonymously with Multi-Peril Crop Insurance. References *{{CRS, article = Report for Congress: Agriculture: A Glossary of Terms, Programs, and Laws, 2005 Edition, url = http://ncseonline.org/nle/crsreports/05jun/97-905.pdf, author= Jasper Womach Agriculture in the United States ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Frederick Blackman
Frederick Frost Blackman FRS (25 July 1866 – 30 January 1947) was a British plant physiologist. Frederick Blackman was born in Lambeth, London to a doctor. He studied medicine at St. Bartholomew's Hospital, graduating MA. In the subsequent years, he studied natural sciences at the University of Cambridge and was awarded DSc. He conducted research on plant physiology, in particular photosynthesis, in Cambridge until his retirement in 1936. Gabrielle Matthaei was his assistant until 1905. He was elected in May 1906 a Fellow of the Royal Society, his candidature citation reading "Fellow of St John's College, Cambridge. Ex-Lecturer and now Reader in Botany in the University." He has made distinguished investigations in plant physiology. In 1921 he was awarded the Royal Medal and in 1923 delivered the Croonian lecture. He was buried at the Parish of the Ascension Burial Ground in Cambridge, with his wife Elsie (1882 - 1967). Blackman's law of limiting factors Blackman propose ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Limiting Factor
A limiting factor is a variable of a system that causes a noticeable change in output or another measure of a type of system. The limiting factor is in a pyramid shape of organisms going up from the producers to consumers and so on. A factor not limiting over a certain domain of starting conditions may yet be limiting over another domain of starting conditions, including that of the factor. Overview The identification of a factor as limiting is possible only in distinction to one or more other factors that are non-limiting. Disciplines differ in their use of the term as to whether they allow the simultaneous existence of more than one limiting factor which (may then be called "co-limiting"), but they all require the existence of at least one non-limiting factor when the terms are used. There are several different possible scenarios of limitation when more than one factor is present. The first scenario, called ''single limitation'' occurs when only one factor, the one with maximum ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Liebig's Law Of The Minimum
Liebig's law of the minimum, often simply called Liebig's law or the law of the minimum, is a principle developed in agricultural science by Carl Sprengel (1840) and later popularized by Justus von Liebig. It states that growth is dictated not by total resources available, but by the scarcest resource (limiting factor). The law has also been applied to biological populations and ecosystem models for factors such as sunlight or mineral nutrients. Applications This was originally applied to plant or crop growth, where it was found that increasing the amount of plentiful nutrients did not increase plant growth. Only by increasing the amount of the limiting nutrient (the one most scarce in relation to "need") was the growth of a plant or crop improved. This principle can be summed up in the aphorism, "The availability of the most abundant nutrient in the soil is only as good as the availability of the least abundant nutrient in the soil." Or, to put it more plainly, "A chain is only ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Law Of Diminishing Returns
In economics, diminishing returns are the decrease in marginal (incremental) output of a production process as the amount of a single factor of production is incrementally increased, holding all other factors of production equal (ceteris paribus). The law of diminishing returns (also known as the law of diminishing marginal productivity) states that in productive processes, increasing a factor of production by one unit, while holding all other production factors constant, will at some point return a lower unit of output per incremental unit of input. The law of diminishing returns does not cause a decrease in overall production capabilities, rather it defines a point on a production curve whereby producing an additional unit of output will result in a loss and is known as negative returns. Under diminishing returns, output remains positive, however productivity and efficiency decrease. The modern understanding of the law adds the dimension of holding other outputs equal, since a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Alexander Mitscherlich (chemist)
Alexander Mitscherlich (28 May 1836 in Berlin – 31 May 1918 in Oberstdorf) was a German chemist and son of Eilhard Mitscherlich. He studied at University of Göttingen, where he also became member of Burschenschaft Hannovera (fraternity). His most important work was in the field of processing wood to create cellulose. He patented an early version of the sulfite process in 1882. In 1909 Mitscherlich wrote on crop yields in agronomy Agronomy is the science and technology of producing and using plants by agriculture for food, fuel, fiber, chemicals, recreation, or land conservation. Agronomy has come to include research of plant genetics, plant physiology, meteorology, and .... His results have been characterized as the "sum of two exponential processes." A historian of plant science wrote in 1942: :A working model of the soil: Liebig's Law of the Minimum was the formulation of an idea that yield of a crop was determined primarily by the amounts of plant food that were pres ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Crop Rotation
Crop rotation is the practice of growing a series of different types of crops in the same area across a sequence of growing seasons. It reduces reliance on one set of nutrients, pest and weed pressure, and the probability of developing resistant pests and weeds. Growing the same crop in the same place for many years in a row, known as monocropping, gradually depletes the soil of certain nutrients and selects for a highly competitive pest and weed community. Without balancing nutrient use and diversifying pest and weed communities, the productivity of monocultures is highly dependent on external inputs. Conversely, a well-designed crop rotation can reduce the need for synthetic fertilizers and herbicides by better using ecosystem services from a diverse set of crops. Additionally, crop rotations can improve soil structure and organic matter, which reduces erosion and increases farm system resilience. History Agriculturalists have long recognized that suitable rotations — such ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Three-field System
The three-field system is a regime of crop rotation in which a field is planted with one set of crops one year, a different set in the second year, and left fallow in the third year. A set of crops is ''rotated'' from one field to another. The technique was first used in China in the Eastern Zhou period, and was adopted in Europe in the medieval period. The three-field system let farmers plant more crops and therefore increase production. Under this system, the arable land of an estate or village was divided into three large fields: one was planted in the autumn with winter wheat or rye; the second field was planted with other crops such as peas, lentils, or beans; and the third was left fallow (unplanted). Cereal crops deplete the ground of nitrogen, but legumes can fix nitrogen and so fertilize the soil. The fallow fields were soon overgrown with weeds and used for grazing farm animals. Their excrement fertilized that field's soil to regain its nutrients. Crop assignments we ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
