A greenhouse is a special structure that is designed to regulate the temperature and humidity of the environment inside. There are different types of greenhouses, but they all have large areas covered with transparent materials that capture sunlight and heat. The most common materials used in modern greenhouses for walls and roofs are rigid plastic made of polycarbonate, plastic film made of polyethylene, or glass panes.[1] When the inside of a greenhouse is exposed to sunlight, the temperature increases, providing a sheltered environment for plants to grow even in cold weather.
The terms greenhouse, glasshouse, and hothouse are often used interchangeably to refer to buildings used for cultivating plants. The specific term used depends on the material and heating system used in the building. Nowadays, greenhouses are more commonly constructed with a variety of materials, such as wood and polyethylene plastic.[2] A glasshouse, on the other hand, is a traditional type of greenhouse made only of glass panes that allow light to enter. The term hothouse indicates that the greenhouse is artificially heated. However, both heated and unheated structures can generally be classified as greenhouses.
Young tomato plants for transplanting in an industrial-sized greenhouse in the Netherlands
Greenhouses can range in size from small sheds to industrial-sized buildings and enormous glasshouses. The smallest example is a miniature greenhouse known as a cold frame, typically used at home, whereas large commercial greenhouses are high tech production facilities for vegetables, flowers or fruits. The glass greenhouses are filled with equipment including screening installations, heating, cooling, and lighting, and may be controlled by a computer to optimize conditions for plant growth. Different techniques are then used to manage growing conditions, including air temperature, relative humidity and vapour-pressure deficit, in order to provide the optimum environment for cultivation of a specific crop.
Before the development of greenhouses, agricultural practices were constrained to weather conditions. According to the climatic zone of communities, people were limited to a select range of species and time of the year in which they could grow plants. Yet around 30 CE, the Roman Empire built the first recorded attempt of an artificial environment.[3] Due to emperor Tiberius's declining health, the royal physicians recommended that the emperor eat one cucumber a day.[3]Cucumbers, however, are quite tender plants and do not grow easily year-round. Therefore, the Romans designed an artificial environment, like a greenhouse, to have cucumbers available for the emperor all year. Cucumbers were planted in wheeled carts which were put in the sun daily, then taken inside to keep them warm at night. The cucumbers were stored under frames or in cucumber houses glazed with either oiled cloth known as specularia or with sheets of selenite (a.k.a. lapis specularis), according to the description by Pliny the Elder.[4][5]
15th-century Korea
The next biggest breakthrough in greenhouse design came from Korea in the 15th century during the Joseon dynasty. In the 1450s, Soon ui Jeon described the first artificially heated greenhouse in his manuscript called Sangayorok.[6] Soon ui Jeon was a physician to the royal family, and Sangayorok was intended to provide the nobility with important agricultural and housekeeping knowledge.[6] Within the section of agricultural techniques, Soon ui Jeon wrote how to build a greenhouse that was able to cultivate vegetables and other plants in the winter.[6] The Korean design adds an ondol system to the structure.[6] An ondol is a Korean heating system used in domestic spaces, which runs a flue pipe from a heat source underneath the flooring.[6] In addition to the ondol, a cauldron filled with water was also heated to create steam and increase the temperature and humidity in the greenhouse.[6] These Korean greenhouses were the first active greenhouses that controlled temperature, rather than only relying on energy from the sun.[2] The design still included passive heating methods, such as semi-transparent oiled hanji windows to capture light and cob walls to retain heat, but the furnace provided extra control over the artificial environment.[6] The Annals of the Joseon Dynasty confirm that greenhouse-like structures incorporating ondol were constructed to provide heat for mandarin orange trees during the winter of 1438.[6]
17th century
The concept of greenhouses also appeared in the Netherlands and then England in the 17th century, along with the plants. Some of these early attempts required enormous amounts of work to close up at night or to winterize. There were serious problems with providing adequate and balanced heat in these early greenhouses. The first 'stove' (heated) greenhouse in the UK was completed at Chelsea Physic Garden by 1681.[7] Today, the Netherlands has many of the largest greenhouses in the world, some of them so vast that they are able to produce millions of vegetables every year.
Experimentation with greenhouse design continued during the 17th century in Europe, as technology produced better glass and construction techniques improved. The greenhouse at the Palace of Versailles was an example of their size and elaborateness; it was more than 150 metres (490ft) long, 13 metres (43ft) wide, and 14 metres (46ft) high.
18th century
Andrew Faneuil, a prosperous Boston merchant, built the first American greenhouse in 1737.[8]
Reconstruction of George Washington's greenhouse at Mount Vernon
When returning to Mount Vernon after the war, George Washington learned of the greenhouse built at the Carroll estate of Mount Clare (Maryland). It was designed by Margaret Tilghman Carroll, an industrious gardener who cultivated citrus trees in this orangery.[9] In 1784 Washington wrote requesting details about the design of her greenhouse, and she complied. Washington wrote:
I shall essay the finishing of my greenhouse this fall, but find that neither myself, nor any person about me is so well skilled in the internal constructions as to proceed without a probability at least of running into errors. Shall I for this reason, ask the favor of you to give me a short description of the Green-house at Mrs. Carrolls? I am persuaded, now that I planned mine on too contracted a scale. My house is (of Brick) 40 feet by 24, in the outer dimensions …[10]
19th century
A heated greenhouse, or "hothouse", In Macon, Georgia c.1877.Interior of a "hothouse" (or greenhouse) in Central City Park, Macon, GA, c.1877.
The French botanist Charles Lucien Bonaparte is often credited with building the first practical modern greenhouse in Leiden, Holland, during the 1800s to grow medicinal tropical plants.[11] Originally only on the estates of the rich, the growth of the science of botany caused greenhouses to spread to the universities. The French called their first greenhouses orangeries, since they were used to protect orange trees from freezing. As pineapples became popular, pineries, or pineapple pits, were built.
The largest glasshouses yet conceived were constructed in England during the Victorian era. As a direct result of colonial expansion, the purpose of glasshouses changed from agriculture to horticulture.[12] The accelerated transfer of plants and horticultural knowledge between colonies contributed to the Victorian fascination with 'exotic' plants and environments.[13] Glasshouses became spectacles to entertain the general public. The curated environments in glasshouses aimed to capture "the Western imagination of an idealised landscape" and support the fantasy of the cultural 'other'.[13] As a consequence, the collection of plants are believed to be true reflections of the world, yet are actually stereotypical arrangements of 'exotic' plants to symbolize exactly where British colonies are and how far their authority reaches.[12] To uphold British hegemony, glasshouses became arguments of colonial power which flaunt the "absolute control of colonized environments and flora...[using plants] as a symbol of British Imperial power.[14]
A prominent design from the 19th century were glasshouses with sufficient height for sizeable trees, called palm houses. These were normally in public gardens or parks and exemplified the 19th-century development of glass and iron architecture. This technology was widely used in railway stations, markets, exhibition halls, and other large buildings that needed large, open internal area. One of the earliest examples of a palm house is in the Belfast Botanic Gardens. Designed by Charles Lanyon, the building was completed in 1840. It was constructed by iron-maker Richard Turner, who would later build the Palm House, Kew Gardens at the Royal Botanic Gardens, Kew, London, in 1848. This came shortly after the Chatsworth Great Conservatory (1837–40) and shortly before The Crystal Palace (1851), both designed by Joseph Paxton, and both now lost.[15]
Greenhouse structures adapted in the 1960s when wider sheets of polyethylene (polythene) film became widely available. Hoop houses were made by several companies and were also frequently made by the growers themselves. Constructed of aluminum extrusions, special galvanized steel tubing, or even just lengths of steel or PVC water pipe, construction costs were greatly reduced. This resulted in many more greenhouses being constructed on smaller farms and garden centers. Polyethylene film durability increased greatly when more effective UV-inhibitors were developed and added in the 1970s; these extended the usable life of the film from one or two years up to three and eventually four or more years.
Gutter-connected greenhouses became more prevalent in the 1980s and 1990s. These greenhouses have two or more bays connected by a common wall, or row of support posts. Heating inputs were reduced as the ratio of floor area to exterior wall area was increased substantially. Gutter-connected greenhouses are now commonly used both in production and in situations where plants are grown and sold to the public as well. Gutter-connected greenhouses are commonly covered with structured polycarbonate materials, or a double layer of polyethylene film with air blown between to provide increased heating efficiencies.
Theory of operation
The warmer temperature in a greenhouse occurs because incident solar radiation passes through the transparent roof and walls and is absorbed by the floor, earth, and contents, which become warmer. These in turn warm up the surrounding air within the greenhouse. As the structure is not open to the atmosphere, the warmed air cannot escape via convection due to the presence of roof and walls, so the temperature inside the greenhouse rises.
This differs from the earth-oriented theory known as the "greenhouse effect",[18][19][20][21] which is a reduction in a planet's heat loss through radiation.
Quantitative studies suggest that the effect of infrared radiative cooling is not negligibly small, and may have economic implications in a heated greenhouse. Analysis of issues of near-infrared radiation in a greenhouse with screens of a high coefficient of reflection concluded that installation of such screens reduced heat demand by about 8%, and application of dyes to transparent surfaces was suggested. Composite less-reflective glass, or less effective but cheaper anti-reflective coated simple glass, also produced savings.[22]
Ventilation
Ventilation is one of the most important components in a successful greenhouse. If there is no proper ventilation, greenhouses and their growing plants can become prone to problems. The main purposes of ventilation is to regulate the temperature and humidity to the optimal level, and to ensure movement of air and thus prevent the build-up of plant pathogens (such as Botrytis cinerea) that prefer still air conditions. Ventilation also ensures a supply of fresh air for photosynthesis and plant respiration, and may enable important pollinators to access the greenhouse crop.
Ventilation can be achieved via the use of vents – often controlled automatically via a computer – and recirculation fans.
Heating or electricity is one of the most considerable costs in the operation of greenhouses across the globe, especially in colder climates. The main problem with heating a greenhouse as opposed to a building that has solid opaque walls is the amount of heat lost through the greenhouse covering. Since the coverings need to allow light to filter into the structure, they conversely cannot insulate very well. With traditional plastic greenhouse coverings having an R-value of around 2, a great amount of money is therefore spent to continually replace the heat lost. Most greenhouses, when supplemental heat is needed use natural gas or electric furnaces.
Passive heating methods exist which seek heat using low energy input. Solar energy can be captured from periods of relative abundance (day time/summer), and released to boost the temperature during cooler periods (night time/winter). Waste heat from livestock can be used to heat greenhouses, e.g., placing a chicken coop inside a greenhouse recovers the heat generated by the chickens, which would otherwise be wasted.[23] Some greenhouses also rely on geothermal heating.[24]
Cooling
Cooling is typically done by opening windows in the greenhouse when it gets too warm for the plants inside it. This can be done manually, or in an automated manner. Window actuators can open windows due to temperature difference or can be opened by electronic controllers. Electronic controllers are often used to monitor the temperature and adjusts the furnace operation to the conditions. This can be as simple as a basic thermostat, but can be more complicated in larger greenhouse operations.
For very hot situations, a shade house providing cooling by shade may be used.
Lighting
During the day, light enters the greenhouse via the windows and is used by the plants. Some greenhouses are also equipped with grow lights (often LED lights) which are switched on at night to increase the amount of light the plants get, hereby increasing the yield with certain crops.[25]
The benefits of carbon dioxide enrichment to about 1100 parts per million in greenhouse cultivation to enhance plant growth has been known for nearly 100 years.[26][27][28] After the development of equipment for the controlled serial enrichment of carbon dioxide, the technique was established on a broad scale in the Netherlands.[29] Secondary metabolites, e.g., cardiac glycosides in Digitalis lanata, are produced in higher amounts by greenhouse cultivation at enhanced temperature and at enhanced carbon dioxide concentration.[30] Carbon dioxide enrichment can also reduce greenhouse water usage by a significant fraction by mitigating the total air-flow needed to supply adequate carbon for plant growth and thereby reducing the quantity of water lost to evaporation.[31] Commercial greenhouses are now frequently located near appropriate industrial facilities for mutual benefit. For example, Cornerways Nursery in the UK is strategically placed near a major sugar refinery,[32] consuming both waste heat and CO2 from the refinery which would otherwise be vented to atmosphere. The refinery reduces its carbon emissions, whilst the nursery enjoys boosted tomato yields and does not need to provide its own greenhouse heating.
Enrichment only becomes effective where, by Liebig's law, carbon dioxide has become the limiting factor. In a controlled greenhouse, irrigation may be trivial, and soils may be fertile by default. In less-controlled gardens and open fields, rising CO2 levels only increase primary production to the point of soil depletion (assuming no droughts,[33][34][35] flooding,[36] or both[37][38][39][40][41]), as demonstrated prima facie by CO2 levels continuing to rise. In addition, laboratory experiments, free air carbon enrichment (FACE) test plots,[42][43] and field measurements provide replicability.[44][45]
Types
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Private greenhouse in Finland.
In domestic greenhouses, the glass used is typically 3mm (or ⅛″) 'horticultural glass' grade, which is good quality glass that should not contain air bubbles (which can produce scorching on leaves by acting like lenses).[46]
Commercial glass greenhouses are often high-tech production facilities for vegetables or flowers. The glass greenhouses are filled with equipment such as screening installations, heating, cooling and lighting, and may be automatically controlled by a computer.
Dutch Light
In the UK and other Northern European countries a pane of horticultural glass referred to as "Dutch Light" was historically used as a standard unit of construction, having dimensions of 28¾″ x 56″ (approx. 730mm x 1422mm). This size gives a larger glazed area when compared with using smaller panes such as the 600mm width typically used in modern domestic designs which then require more supporting framework for a given overall greenhouse size. A style of greenhouse having sloped sides (resulting in a wider base than at eaves height) and using these panes uncut is also often referred to as "Dutch Light design", and a cold frame using a full- or half-pane as being of "Dutch" or "half-Dutch" size.
Greenhouses with spectrally selective solar modules
Potential new photovoltaic technologies which let through the colors of light needed by the interior plants, but use the other wavelengths to generate electricity, might one day have some future use in greenhouses. There are prototypes of such greenhouses.[47][48] "Semi-transparent" PV panels used in agrivoltaics increase the spacing between solar cells and use clear backsheets enhancing food production below. In this option, the fixed PV panels enable the east–west movement of the sun to "spray sunlight" over the plants below, thereby reducing "over-exposure" due to the day-long sun as in transparent greenhouses, as they generate electricity above.[49]
Uses
Greenhouses allow for greater control over the growing environment of plants. Depending upon the technical specification of a greenhouse, key factors that may be controlled include temperature, levels of light and shade, irrigation, fertilizer application, and atmospheric humidity. Greenhouses may be used to overcome shortcomings in the growing qualities of a piece of land, such as a short growing season or poor light levels, and they can thereby improve food production in marginal environments. Shade houses are used specifically to provide shade in hot, dry climates.[50][51]
As they may enable certain crops to be grown throughout the year, greenhouses are increasingly important in the food supply of high-latitude countries. One of the largest complexes in the world is in Almería, Andalucía, Spain, where greenhouses cover almost 200km2 (49,000 acres).[52]
Greenhouses are often used for growing flowers, vegetables, fruits, and transplants. Special greenhouse varieties of certain crops, such as tomatoes, are generally used for commercial production.
Many vegetables and flowers can be grown in greenhouses in late winter and early spring, and then transplanted outside as the weather warms. Seed tray racks can also be used to stack seed trays inside the greenhouse for later transplanting outside. Hydroponics (especially hydroponic A-frames) can be used to make the most use of the interior space when growing crops to mature size inside the greenhouse.
The relatively closed environment of a greenhouse has its unique management requirements, compared with outdoor production. Pests and diseases, and extremes of temperature and humidity, have to be controlled, and irrigation is necessary to provide water. Most greenhouses use sprinklers or drip lines. Significant inputs of heat and light may be required, particularly with winter production of warm-weather vegetables.
An "alpine house" is a specialized greenhouse used for growing alpine plants. The purpose of an alpine house is to mimic the conditions in which alpine plants grow; particularly to protect from wet conditions in winter. Alpine houses are often unheated since the plants grown there are hardy, or require at most protection from hard frost in the winter. They are designed to have excellent ventilation.[54]
The Netherlands has some of the largest greenhouses in the world. Such is the scale of food production in the country that in 2017, greenhouses occupied nearly 5,000 hectares.[56]
Greenhouses began to be built in the Westland region of the Netherlands in the mid-19th century. The addition of sand to bogs and clay soil created fertile soil for agriculture, and around 1850, grapes were grown in the first greenhouses, simple glass constructions with one of the sides consisting of a solid wall. By the early 20th century, greenhouses began to be constructed with all sides built using glass, and they began to be heated. This also allowed for the production of fruits and vegetables that did not ordinarily grow in the area. Today, the Westland and the area around Aalsmeer have the highest concentration of greenhouse agriculture in the world.[57] The Westland produces mostly vegetables, besides plants and flowers; Aalsmeer is noted mainly for the production of flowers and potted plants. Since the 20th century, the area around Venlo and parts of Drenthe have also become important regions for greenhouse agriculture.
Since 2000, technical innovations have included the "closed greenhouse", a completely closed system allowing the grower complete control over the growing process while using less energy. Floating greenhouses[clarification needed] are used in watery areas of the country.
The Netherlands has around 4,000 greenhouse enterprises that operate over 9,000 hectares[58] of greenhouses and employ some 150,000 workers, producing €7.2 billion[59] worth of vegetables, fruit, plants, and flowers, some 80% of which is exported.[citation needed][60][61]
Pliny the Elder with John Bostock and H. T. Riley, trans., Natural History (London, England: Henry G. Bohn, 1856), vol. 4, book 19, chapter 23: "Vegetables of a cartilaginous nature – cucumbers. Pepones.", p. 156.
The Roman poet Martial also briefly mentions greenhouses or cold frames in: Martial with Walter C. A. Ker, trans., Epigrams (London: William Heinemann, 1920), vol. 2, book 8 (VIII ), no. 14 (XIV), p. 13.
↑ rogue classicism: Roman Greenhouses?Cartilaginum generis extraque terram est cucumis mira voluptate Tiberio principi expetitus Nullo quippe non die contigit ei pensiles eorum hortos promoventibus in solem rotis olitoribus rursusque hibernis diebus intra specularium munimenta revocantibus
1 2 3 4 5 6 7 8 Yoon, Sang Jun; Woudstra, Jan (Summer 2007). "Advanced Horticultural Techniques in Korea: The Earliest Documented Greenhouses". Garden History. 35 (1): 68–84. JSTOR25472355.
↑ Minter, Sue (2003). The Apothecaries' Garden. Sutton. p.4. ISBN978-0750936385.
1 2 Evans, Evie. "Cultivating Colonialism: The Musealisation Of Natural Object In the Hortus Botanicus, Amsterdam, And The Royal Botanic Gardens, Kew." (Master's thesis, University of Amsterdam, 2021). FramerFramed.
↑ Reinau, E. (1927) Praktische Kohlensäuredüngung, Springer, Berlin
↑ Brijer, C. J. (1959) "Een verlaten goudmijn: koolzuurbemesting". In: Mededelingenvan de DirectieTuinbouw. Ministerie van Landbouw en Visserij, Nederland. Vol. 22, pp. 670–674
Solar energy is radiant light and heat from the Sun that is harnessed using a range of technologies such as solar power to generate electricity, solar thermal energy, and solar architecture. It is an essential source of renewable energy, and its technologies are broadly characterized as either passive solar or active solar depending on how they capture and distribute solar energy or convert it into solar power. Active solar techniques include the use of photovoltaic systems, concentrated solar power, and solar water heating to harness the energy. Passive solar techniques include orienting a building to the Sun, selecting materials with favorable thermal mass or light-dispersing properties, and designing spaces that naturally circulate air.
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.
Electric power systems consist of generation plants of different energy sources, transmission networks, and distribution lines. Each of these components can have environmental impacts at multiple stages of their development and use including in their construction, during the generation of electricity, and in their decommissioning and disposal. These impacts can be split into operational impacts and construction impacts. All forms of electricity generation have some form of environmental impact, but coal-fired power is the dirtiest. This page is organized by energy source and includes impacts such as water usage, emissions, local pollution, and wildlife displacement.
A polytunnel 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 is represented in current practice. The nesting of row covers and low tunnels inside high tunnels is also common.
In agriculture and gardening, a cold frame is a transparent-roofed enclosure, built low to the ground, used to protect plants from adverse weather, primarily excessive cold or wet. The transparent top admits sunlight and prevents heat escape via convection that would otherwise occur, particularly at night. Essentially, a cold frame functions as a miniature greenhouse to extend the growing season.
A fossil fuel power station is a thermal power station which burns a fossil fuel, such as coal or natural gas, to produce electricity. Fossil fuel power stations have machinery to convert the heat energy of combustion into mechanical energy, which then operates an electrical generator. The prime mover may be a steam turbine, a gas turbine or, in small plants, a reciprocating gas engine. All plants use the energy extracted from the expansion of a hot gas, either steam or combustion gases. Although different energy conversion methods exist, all thermal power station conversion methods have their efficiency limited by the Carnot efficiency and therefore produce waste heat.
Bioenergy is a type of renewable energy that is derived from plants and animal waste. The biomass that is used as input materials consists of recently living organisms, mainly plants. Thus, fossil fuels are not regarded as biomass under this definition. Types of biomass commonly used for bioenergy include wood, food crops such as corn, energy crops and waste from forests, yards, or farms.
Vertical farming is the practice of growing crops in vertically stacked layers. It often incorporates controlled-environment agriculture, which aims to optimize plant growth, and soilless farming techniques such as hydroponics, aquaponics, and aeroponics. Some common choices of structures to house vertical farming systems include buildings, shipping containers, underground tunnels, and abandoned mine shafts.
Plasticulture is the practice of using plastic materials in agricultural applications. The plastic materials themselves are often and broadly referred to as "ag plastics". Plasticulture ag plastics include soil fumigation film, irrigation drip tape/tubing, plastic plant packaging cord, nursery pots and bales, but the term is most often used to describe all kinds of plastic plant/soil coverings. Such coverings range from plastic mulch film, row coverings, high and low tunnels (polytunnels), to plastic greenhouses.
Controlled-environment agriculture (CEA) -- which includes indoor agriculture (IA) and vertical farming—is a technology-based approach toward food production. The aim of CEA is to provide protection from the outdoor elements and maintain optimal growing conditions throughout the development of the crop. Production takes place within an enclosed growing structure such as a greenhouse or plant factory.
Greenhouse gas (GHG) emissions from human activities intensify the greenhouse effect. This contributes to climate change. Carbon dioxide, from burning fossil fuels such as coal, oil, and natural gas, is one of the most important factors in causing climate change. The largest emitters are China followed by the United States. The United States has higher emissions per capita. The main producers fueling the emissions globally are large oil and gas companies. Emissions from human activities have increased atmospheric carbon dioxide by about 50% over pre-industrial levels. The growing levels of emissions have varied, but have been consistent among all greenhouse gases. Emissions in the 2010s averaged 56 billion tons a year, higher than any decade before. Total cumulative emissions from 1870 to 2017 were 425±20 GtC from fossil fuels and industry, and 180±60 GtC from land use change. Land-use change, such as deforestation, caused about 31% of cumulative emissions over 1870–2017, coal 32%, oil 25%, and gas 10%.
Soil solarization is a non-chemical environmentally friendly method for controlling pests using solar power to increase the soil temperature to levels at which many soil-borne plant pathogens will be killed or greatly weakened. Soil solarization is used in warm climates on a relatively small scale in gardens and organic farms. Soil solarization weakens and kills fungi, bacteria, nematodes, and insect and mite pests along with weeds in the soil by mulching the soil and covering it with a tarp, usually with a transparent polyethylene cover to trap solar energy. This energy causes physical, chemical, and biological changes in the soil community. Soil solarization is dependent upon time, temperature, and soil moisture. It may also be described as methods of decontaminating soil or creating suppressive soils by the use of sunlight.
This is a glossary of environmental science.
Nutrient film technique (NFT) is a hydroponic technique where in a very shallow stream of water containing all the dissolved nutrients required for plant growth is re-circulated past the bare roots of plants in a watertight gully, also known as channels.
Many types of flowering plants are available to plant in flower gardens or flower beds. The floral industry calls these plants, bedding plants. These fast-growing plants in seasonal flower beds create colourful displays, during spring, summer, fall or winter, depending on the climate. Plants used for bedding are generally annuals, but biennials, tender perennials, and succulents are used.
An Eco-house (or Eco-home) is an environmentally low-impact home designed and built using materials and technology that reduces its carbon footprint and lowers its energy needs. Eco-homes are measured in multiple ways meeting sustainability needs such as water conservation, reducing wastes through reusing and recycling materials, controlling pollution to limit global warming, energy generation and conservation, and decreasing CO2 emissions.
Building-integrated agriculture (BIA) is the practice of locating high-performance hydroponic greenhouse farming systems on and in mixed-use buildings to exploit synergies between the built environment and agriculture.
Climate-friendly gardening is a form of gardening that can reduce emissions of greenhouse gases from gardens and encourage the absorption of carbon dioxide by soils and plants in order to aid the reduction of global warming. To be a climate-friendly gardener means considering both what happens in a garden and the materials brought into it as well as the impact they have on land use and climate. It can also include garden features or activities in the garden that help to reduce greenhouse gas emissions through processes not directly related to gardening.
The CO2 fertilization effect or carbon fertilization effect causes an increased rate of photosynthesis while limiting leaf transpiration in plants. Both processes result from increased levels of atmospheric carbon dioxide (CO2). The carbon fertilization effect varies depending on plant species, air and soil temperature, and availability of water and nutrients. Net primary productivity (NPP) might positively respond to the carbon fertilization effect. Although, evidence shows that enhanced rates of photosynthesis in plants due to CO2 fertilization do not directly enhance all plant growth, and thus carbon storage. The carbon fertilization effect has been reported to be the cause of 44% of gross primary productivity (GPP) increase since the 2000s. Earth System Models, Land System Models and Dynamic Global Vegetation Models are used to investigate and interpret vegetation trends related to increasing levels of atmospheric CO2. However, the ecosystem processes associated with the CO2 fertilization effect remain uncertain and therefore are challenging to model.
Digeponics (pronounced die-jeh-ponics, as in digestion) is a method of agriculture which integrates the products of anaerobic digestion, including CO2 and digestate, with greenhouse cultivation of vegetables.
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