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Polytunnel
A polytunnel (also known as a polyhouse, hoop greenhouse or hoophouse, grow tunnel or high tunnel) is a tunnel typically made from steel and covered in polyethylene, usually semi-circular, square or elongated in shape. The interior heats up because incoming solar radiation from the sun warms plants, soil, and other things inside the building faster than heat can escape the structure. Air warmed by the heat from hot interior surfaces is retained in the building by the roof and wall. Temperature, humidity and ventilation can be controlled by equipment fixed in the polytunnel or by manual opening and closing of vents. Polytunnels are mainly used in temperate regions in similar ways to glass greenhouses and row covers. Besides the passive solar heating that every polytunnel provides, every variation of auxiliary heating (from hothouse heating through minimal heating to unheated houses) is represented in current practice. The nesting of row covers and low tunnels inside high tunnels is ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Polytunnel Balhungie
A polytunnel (also known as a polyhouse, hoop greenhouse or hoophouse, grow tunnel or high tunnel) is a tunnel typically made from steel and covered in polyethylene, usually semi-circular, square or elongated in shape. The interior heats up because incoming solar radiation from the sun warms plants, soil, and other things inside the building faster than heat can escape the structure. Air warmed by the heat from hot interior surfaces is retained in the building by the roof and wall. Temperature, humidity and ventilation (architecture), ventilation can be controlled by equipment fixed in the polytunnel or by manual opening and closing of vents. Polytunnels are mainly used in temperate regions in similar ways to glass greenhouses and row covers. Besides the passive solar heating that every polytunnel provides, every variation of auxiliary heating (from hothouse heating through minimal heating to unheated houses) is represented in current practice. The nesting of row covers and low tu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Season Extension
Season extension in agriculture is any method that allows a crop to be grown beyond its normal outdoor growing season and harvesting time frame, or the extra time thus achieved. To extend the growing season into the colder months, one can use unheated techniques such as floating row covers, low tunnels, caterpillar tunnels, or hoophouses. However, even if colder temperatures are mitigated, most crops will stop growing when the days become shorter than 10 hours, and resume after winter as the daylight increases above 10 hours. A hothouse — a greenhouse which is heated and illuminated — creates an environment where plants are fooled into thinking it is their normal growing season. Though this ''is'' a form of season extension for the grower, it is not the usual meaning of the term. Season extension can apply to other climates, where conditions other than cold and shortened period of sunlight end the growing year (e.g. a rainy season). Structures * Unheated greenhouses (also ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Vegetable
Vegetables are parts of plants that are consumed by humans or other animals as food. The original meaning is still commonly used and is applied to plants collectively to refer to all edible plant matter, including the flowers, fruits, stems, leaves, roots, and seeds. An alternative definition of the term is applied somewhat arbitrarily, often by culinary and cultural tradition. It may exclude foods derived from some plants that are fruits, flowers, nuts, and cereal grains, but include savoury fruits such as tomatoes and courgettes, flowers such as broccoli, and seeds such as pulses. Originally, vegetables were collected from the wild by hunter-gatherers and entered cultivation in several parts of the world, probably during the period 10,000 BC to 7,000 BC, when a new agricultural way of life developed. At first, plants which grew locally would have been cultivated, but as time went on, trade brought exotic crops from elsewhere to add to domestic types. Nowadays, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Row Cover
In agriculture and gardening, row cover is any transparent or semi-transparent flexible material, like fabric or plastic sheeting, used as a protective covering for plants, usually vegetables. Covers are used to extend growing seasons, and reduce undesirable effects of cold, wind and insects. Article marked reviewed by publisher in 2012. Row covers can reduce the drying effect of wind, and can provide a small amount of warming in a similar way to unheated cold frames, greenhouses and polytunnels, creating a microclimate for the plants. The first commercial-scale use of polyethylene row covers in the US was in the 1950s, and by the 1980s their use was widespread. Row cover is a lightweight synthetic, such as clear plastic (polyethylene) or spunbonded polyester called horticultural fleece. Plastic covers are elevated above plants on a supporting framework such as wire hoops to form a low tunnel. (Plastic placed directly on the ground is mulch.) Fleece covers can be placed directl ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Solar Radiation
Solar irradiance is the power per unit area (surface power density) received from the Sun in the form of electromagnetic radiation in the wavelength range of the measuring instrument. Solar irradiance is measured in watts per square metre (W/m2) in SI units. Solar irradiance is often integrated over a given time period in order to report the radiant energy emitted into the surrounding environment (joule per square metre, J/m2) during that time period. This integrated solar irradiance is called solar irradiation, solar exposure, solar insolation, or insolation. Irradiance may be measured in space or at the Earth's surface after atmospheric absorption and scattering. Irradiance in space is a function of distance from the Sun, the solar cycle, and cross-cycle changes.Michael Boxwell, ''Solar Electricity Handbook: A Simple, Practical Guide to Solar Energy'' (2012), p. 41–42. Irradiance on the Earth's surface additionally depends on the tilt of the measuring surface, the height ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Drying
Drying is a mass transfer process consisting of the removal of water or another solvent by evaporation from a solid, semi-solid or liquid. This process is often used as a final production step before selling or packaging products. To be considered "dried", the final product must be solid, in the form of a continuous sheet (e.g., paper), long pieces (e.g., wood), particles (e.g., cereal grains or corn flakes) or powder (e.g., sand, salt, washing powder, milk powder). A source of heat and an agent to remove the vapor produced by the process are often involved. In bioproducts like food, grains, and pharmaceuticals like vaccines, the solvent to be removed is almost invariably water. Desiccation may be synonymous with drying or considered an extreme form of drying. In the most common case, a gas stream, e.g., air, applies the heat by convection and carries away the vapor as humidity. Other possibilities are vacuum drying, where heat is supplied by conduction or radiation (or microwave ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Strawberries
The garden strawberry (or simply strawberry; ''Fragaria × ananassa'') is a widely grown hybrid species of the genus '' Fragaria'', collectively known as the strawberries, which are cultivated worldwide for their fruit. The fruit is widely appreciated for its characteristic aroma, bright red color, juicy texture, and sweetness. It is consumed in large quantities, either fresh or in such prepared foods as jam, juice, pies, ice cream, milkshakes, and chocolates. Artificial strawberry flavorings and aromas are also widely used in products such as candy, soap, lip gloss, perfume, and many others. The garden strawberry was first bred in Brittany, France, in the 1750s via a cross of ''Fragaria virginiana'' from eastern North America and ''Fragaria chiloensis'', which was brought from Chile by Amédée-François Frézier in 1714. Cultivars of ''Fragaria'' × ''ananassa'' have replaced, in commercial production, the woodland strawberry ('' Fragaria vesca''), which was the first straw ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Poultry
Poultry () are domesticated birds kept by humans for their eggs, their meat or their feathers. These birds are most typically members of the superorder Galloanserae (fowl), especially the order Galliformes (which includes chickens, quails, and turkeys). The term also includes birds that are killed for their meat, such as the young of pigeons (known as squabs) but does not include similar wild birds hunted for sport or food and known as game. The word "poultry" comes from the French/Norman word ''poule'', itself derived from the Latin word ''pullus'', which means "small animal". Recent genomic study involving the four extant Junglefowl species reveals that the domestication of chicken, the most populous poultry species, occurred around 8,000 years ago in Southeast Asia - although this was previously believed to have occurred later - around 5,400 years ago - in Southeast Asia. The process may have originally occurred as a result of people hatching and rearing young birds fro ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Calf (animal)
A calf ( : calves) is a young domestic cow or bull. Calves are reared to become adult cattle or are slaughtered for their meat, called veal, and hide. The term ''calf'' is also used for some other species. See "Other animals" below. Terminology "Calf" is the term used from birth to weaning, when it becomes known as a ''weaner'' or ''weaner calf'', though in some areas the term "calf" may be used until the animal is a yearling. The birth of a calf is known as ''calving''. A calf that has lost its mother is an orphan calf, also known as a ''poddy'' or ''poddy-calf'' in British. ''Bobby calves'' are young calves which are to be slaughtered for human consumption. A ''vealer'' is a calf weighing less than about which is at about eight to nine months of age. A young female calf from birth until she has had a calf of her own is called a ''heifer'' (). In the American Old West, a motherless or small, runty calf was sometimes referred to as a dodie. The term "calf" is also used for ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Goats
The goat or domestic goat (''Capra hircus'') is a domesticated species of Caprinae, goat-antelope typically kept as livestock. It was domesticated from the wild goat (''C. aegagrus'') of Southwest Asia and Eastern Europe. The goat is a member of the animal family Bovidae and the tribe Caprini, meaning it is closely related to the sheep. There are over 300 distinct breeds of goat.Hirst, K. Kris"The History of the Domestication of Goats".''About.com''. Accessed August 18, 2008. It is one of the oldest domesticated species of animal, according to archaeological evidence that its earliest domestication occurred in Iran at 10,000 calibrated calendar years ago. Goats have been used for milk, Goat meat, meat, Animal fur, fur, and Animal skin, skins across much of the world. Milk from goats is often turned into goat cheese. Female goats are referred to as ''does'' or ''nannies'', Entire (animal), intact males are called ''bucks'' or ''billies'', and juvenile goats of both sexes are ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Alpacas
The alpaca (''Lama pacos'') is a species of South American camelid mammal. It is similar to, and often confused with, the llama. However, alpacas are often noticeably smaller than llamas. The two animals are closely related and can successfully crossbreed. Both species are believed to have been domesticated from their wild relatives, the vicuña and guanaco. There are two breeds of alpaca: the Suri alpaca and the Huacaya alpaca. Alpacas are kept in herds that graze on the level heights of the Andes of Southern Peru, Western Bolivia, Ecuador, and Northern Chile at an altitude of above sea level. Alpacas are considerably smaller than llamas, and unlike llamas, they were not bred to be working animals, but were bred specifically for their fiber. Alpaca fiber is used for making knitted and woven items, similar to sheep's wool. These items include blankets, sweaters, hats, gloves, scarves, a wide variety of textiles, and ponchos, in South America, as well as sweaters, socks, coat ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sheep
Sheep or domestic sheep (''Ovis aries'') are domesticated, ruminant mammals typically kept as livestock. Although the term ''sheep'' can apply to other species in the genus ''Ovis'', in everyday usage it almost always refers to domesticated sheep. Like all ruminants, sheep are members of the order Artiodactyla, the even-toed ungulates. Numbering a little over one billion, domestic sheep are also the most numerous species of sheep. An adult female is referred to as a ''ewe'' (), an intact male as a ''ram'', occasionally a ''tup'', a castrated male as a ''wether'', and a young sheep as a ''lamb''. Sheep are most likely descended from the wild mouflon of Europe and Asia, with Iran being a geographic envelope of the domestication center. One of the earliest animals to be domesticated for agricultural purposes, sheep are raised for fleeces, meat (lamb, hogget or mutton) and milk. A sheep's wool is the most widely used animal fiber, and is usually harvested by shearing. In Commonw ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
