Transpiration

Last updated
Overview of transpiration: Water is passively transported into the roots and then into the xylem. The forces of cohesion and adhesion cause the water molecules to form a column in the xylem. Water moves from the xylem into the mesophyll cells, evaporates from their surfaces and leaves the plant by diffusion through the stomata Transpiration Overview.svg
Overview of transpiration:
  1. Water is passively transported into the roots and then into the xylem.
  2. The forces of cohesion and adhesion cause the water molecules to form a column in the xylem.
  3. Water moves from the xylem into the mesophyll cells, evaporates from their surfaces and leaves the plant by diffusion through the stomata
Transpiration of water in xylem Transpiration of Water in Xylem.svg
Transpiration of water in xylem
Stoma in a tomato leaf shown via colorized scanning electron microscope Tomato leaf stomate 1-color.jpg
Stoma in a tomato leaf shown via colorized scanning electron microscope
The clouds in this image of the Amazon Rainforest are a result of evapotranspiration. Afternoon Clouds over the Amazon Rainforest.jpg
The clouds in this image of the Amazon Rainforest are a result of evapotranspiration.

Transpiration is the process of water movement through a plant and its evaporation from aerial parts, such as leaves, stems and flowers. It is a passive process that requires no energy expense by the plant. [1] Transpiration also cools plants, changes osmotic pressure of cells, and enables mass flow of mineral nutrients. When water uptake by the roots is less than the water lost to the atmosphere by evaporation, plants close small pores called stomata to decrease water loss, which slows down nutrient uptake and decreases CO2 absorption from the atmosphere limiting metabolic processes, photosynthesis, and growth. [2]

Contents

Water and nutrient uptake

Water is necessary for plants, but only a small amount of water taken up by the roots is used for growth and metabolism. The remaining 97–99.5% is lost by transpiration and guttation. [3] Water with any dissolved mineral nutrients is absorbed into the roots by osmosis, which travels through the xylem by way of water molecule adhesion and cohesion to the foliage and out small pores called stomata (singular "stoma"). [4] The stomata are bordered by guard cells and their stomatal accessory cells (together known as stomatal complex) that open and close the pore. [5] The cohesion-tension theory explains how leaves pull water through the xylem. Water molecules stick together or exhibit cohesion. As a water molecule evaporates from the leaf's surface, it pulls on the adjacent water molecule, creating a continuous water flow through the plant. [6]

Two major factors influence the rate of water flow from the soil to the roots: the hydraulic conductivity of the soil and the magnitude of the pressure gradient through the soil. Both of these factors influence the rate of bulk flow of water moving from the roots to the stomatal pores in the leaves via the xylem. [7] Mass flow of liquid water from the roots to the leaves is driven in part by capillary action, but primarily driven by water potential differences. If the water potential in the ambient air is lower than that in the leaf airspace of the stomatal pore, water vapor will travel down the gradient and move from the leaf airspace to the atmosphere. This movement lowers the water potential in the leaf airspace and causes evaporation of liquid water from the mesophyll cell walls. This evaporation increases the tension on the water menisci in the cell walls and decreases their radius, thus exerting tension in the cells' water. Because of the cohesive properties of water, the tension travels through the leaf cells to the leaf and stem xylem, where a momentary negative pressure is created as water is pulled up the xylem from the roots. [8] In taller plants and trees, the force of gravity pulling the water inside can only be overcome by the decrease in hydrostatic pressure in the upper parts of the plants due to the diffusion of water out of stomata into the atmosphere. [3]

Etymology

We can see the history of the word transpiration when we break it down into trans, a Latin preposition that means "across," and spiration, which comes from the Latin verb spīrāre, meaning "to breathe." The motion suffix adds the meaning "the act of," so we can see transpiration is, literally, "the ACT of breathing across," which clearly identifies vapor emission from plant leaves.

Capillary action

Capillary action is the process of a liquid flowing in narrow spaces without the assistance of, or even in opposition to, external forces like gravity. The effect can be seen in the drawing up of liquids between the hairs of a paint-brush, in a thin tube, in porous materials such as paper and plaster, in some non-porous materials such as sand and liquefied carbon fiber, or in a biological cell. It occurs because of intermolecular forces between the liquid and surrounding solid surfaces. If the diameter of the tube is sufficiently small, then the combination of surface tension (which is caused by cohesion within the liquid) and adhesive forces between the liquid and container wall act to propel the liquid.[ citation needed ]

Regulation

Plants regulate the rate of transpiration by controlling the size of the stomatal apertures. The rate of transpiration is also influenced by the evaporative demand of the atmosphere surrounding the leaf such as boundary layer conductance, humidity, temperature, wind, and incident sunlight. Along with above-ground factors, soil temperature and moisture can influence stomatal opening, [9] and thus transpiration rate. The amount of water lost by a plant also depends on its size and the amount of water absorbed at the roots. Factors that effect root absorption of water include: moisture content of the soil, excessive soil fertility or salt content, poorly developed root systems, and those impacted by pathogenic bacteria and fungi such as pythium or rhizoctonia.

FeatureEffect on transpiration
Number of leavesMore leaves (or spines, or other photosynthesizing organs) means a bigger surface area and more stomata for gaseous exchange. This will result in greater water loss.
Number of stomataMore stomata will provide more pores for transpiration.
Size of the leafA leaf with a bigger surface area will transpire faster than a leaf with a smaller surface area.
Presence of plant cuticle A waxy cuticle is relatively impermeable to water and water vapor and reduces evaporation from the plant surface except via the stomata. A reflective cuticle will reduce solar heating and temperature rise of the leaf, helping to reduce the rate of evaporation. Tiny hair-like structures called trichomes on the surface of leaves also can inhibit water loss by creating a high humidity environment at the surface of leaves. These are some examples of the adaptations of plants for the conservation of water that may be found on many xerophytes.
Light supplyThe rate of transpiration is controlled by the stomatal aperture, and these small pores open especially for photosynthesis. While there are exceptions to this (such as night or CAM photosynthesis), in general, a light supply will encourage open stomata.
TemperatureTemperature affects the rate in two ways:

1) An increased rate of evaporation due to a temperature rise will hasten the loss of water.
2) Decreased relative humidity outside the leaf will increase the water potential gradient.

Relative humidityDrier surroundings give a steeper water potential gradient, and so increase the rate of transpiration.
WindIn still air, water lost due to transpiration can accumulate in the form of vapor close to the leaf surface. This will reduce the rate of water loss, as the water potential gradient from inside to outside of the leaf is then slightly less. The wind blows away much of this water vapor near the leaf surface, making the potential gradient steeper and speeding up the diffusion of water molecules into the surrounding air. Even in wind, though, there may be some accumulation of water vapor in a thin boundary layer of slower moving air next to the leaf surface. The stronger the wind, the thinner this layer will tend to be, and the steeper the water potential gradient.
Water supply Water stress caused by restricted water supply from the soil may result in stomatal closure and reduce the rates of transpiration.
Some xerophytes will reduce the surface of their leaves during water deficiencies (left). If temperatures are cool enough and water levels are adequate the leaves expand again (right). Xerophyte.png
Some xerophytes will reduce the surface of their leaves during water deficiencies (left). If temperatures are cool enough and water levels are adequate the leaves expand again (right).

During a growing season, a leaf will transpire many times more water than its own weight. An acre of corn gives off about 3,000–4,000 gallons (11,400–15,100 liters) of water each day, and a large oak tree can transpire 40,000 gallons (151,000 liters) per year. The transpiration ratio is the ratio of the mass of water transpired to the mass of dry matter produced; the transpiration ratio of crops tends to fall between 200 and 1000 (i.e., crop plants transpire 200 to 1000 kg of water for every kg of dry matter produced). [10]

Transpiration rates of plants can be measured by a number of techniques, including potometers, lysimeters, porometers, photosynthesis systems and thermometric sap flow sensors. Isotope measurements indicate transpiration is the larger component of evapotranspiration. [11] Recent evidence from a global study [12] of water stable isotopes shows that transpired water is isotopically different from groundwater and streams. This suggests that soil water is not as well mixed as widely assumed. [13]

Desert plants have specially adapted structures, such as thick cuticles, reduced leaf areas, sunken stomata and hairs to reduce transpiration and conserve water. Many cacti conduct photosynthesis in succulent stems, rather than leaves, so the surface area of the shoot is very low. Many desert plants have a special type of photosynthesis, termed crassulacean acid metabolism or CAM photosynthesis, in which the stomata are closed during the day and open at night when transpiration will be lower. [14]

Cavitation

To maintain the pressure gradient necessary for a plant to remain healthy they must continuously uptake water with their roots. They need to be able to meet the demands of water lost due to transpiration. If a plant is incapable of bringing in enough water to remain in equilibrium with transpiration an event known as cavitation occurs. [15] Cavitation is when the plant cannot supply its xylem with adequate water so instead of being filled with water the xylem begins to be filled with water vapor. These particles of water vapor come together and form blockages within the xylem of the plant. This prevents the plant from being able to transport water throughout its vascular system. [16] There is no apparent pattern of where cavitation occurs throughout the plant's xylem. If not effectively taken care of, cavitation can cause a plant to reach its permanent wilting point, and die. Therefore, the plant must have a method by which to remove this cavitation blockage, or it must create a new connection of vascular tissue throughout the plant. [17] The plant does this by closing its stomates overnight, which halts the flow of transpiration. This then allows for the roots to generate over 0.05 mPa of pressure, and that is capable of destroying the blockage and refilling the xylem with water, reconnecting the vascular system. If a plant is unable to generate enough pressure to eradicate the blockage it must prevent the blockage from spreading with the use of pit pears and then create new xylem that can re-connect the vascular system of the plant. [18]

Scientists have begun using magnetic resonance imaging (MRI) to monitor the internal status of the xylem during transpiration, in a non invasive manner. This method of imaging allows for scientists to visualize the movement of water throughout the entirety of the plant. It also is capable of viewing what phase the water is in while in the xylem, which makes it possible to visualize cavitation events. Scientists were able to see that over the course of 20 hours of sunlight more than 10 xylem vessels began filling with gas particles becoming cavitated. MRI technology also made it possible to view the process by which these xylem structures are repaired in the plant. After three hours in darkness it was seen that the vascular tissue was resupplied with liquid water. This was possible because in darkness the stomates of the plant are closed and transpiration no longer occurs. When transpiration is halted the cavitation bubbles are destroyed by the pressure generated by the roots. These observations suggest that MRIs are capable of monitoring the functional status of xylem and allows scientists to view cavitation events for the first time. [17]

Effects on the environment

Cooling

Transpiration cools plants, as the evaporating water carries away heat energy due to its large latent heat of vaporization of 2260 kJ per liter.

This section is an excerpt from Transpirational cooling (biological).[ edit ]

Transpirational cooling is the cooling provided as plants transpire water. Excess heat generated from solar radiation is damaging to plant cells and thermal injury occurs during drought or when there is rapid transpiration which produces wilting. [19] Green vegetation contributes to moderating climate by being cooler than adjacent bare earth or constructed areas. As plant leaves transpire they use energy to evaporate water aggregating up to a huge volume globally every day.

An individual tree can transpire hundreds of liters of water per day. For every 100 liters of water transpired, the tree then cools by 70 kWh. [20] [21] Urban heat island effects can be attributed to the replacement of vegetation by constructed surfaces. Deforested areas reveal a higher temperature than adjacent intact forest. Forests and other natural ecosystems support climate stabilisation.

The Earth’s energy budget reveals pathways to mitigate climate change using our knowledge of the efficacy of how plants cool.

See also

Wikisource-logo.svg
Wikisource has the text of the 1905 New International Encyclopedia article " Transpiration ".

Related Research Articles

<span class="mw-page-title-main">Xylem</span> Water transport tissue in vascular plants

Xylem is one of the two types of transport tissue in vascular plants, the other being phloem; both of these are part of the vascular bundle. The basic function of the xylem is to transport water upward from the roots to parts of the plants such as stems and leaves, but also transports nutrients. The word xylem is derived from the Ancient Greek word ξύλον (xylon), meaning "wood"; the best-known xylem tissue is wood, though it is found throughout a plant. The term was introduced by Carl Nägeli in 1858.

<span class="mw-page-title-main">Vascular plant</span> Clade of plants with xylem and phloem

Vascular plants, also called tracheophytes or collectively tracheophyta, are plants that have lignified tissues for conducting water and minerals throughout the plant. They also have a specialized non-lignified tissue to conduct products of photosynthesis. The group includes most land plants other than mosses.

<span class="mw-page-title-main">Stoma</span> In plants, a variable pore between paired guard cells

In botany, a stoma, also called a stomate, is a pore found in the epidermis of leaves, stems, and other organs, that controls the rate of gas exchange between the internal air spaces of the leaf and the atmosphere. The pore is bordered by a pair of specialized parenchyma cells known as guard cells that regulate the size of the stomatal opening.

<span class="mw-page-title-main">Guttation</span> Exudations of xylem sap

Guttation is the exudation of drops of xylem and phloem sap on the tips or edges of leaves of some vascular plants, such as grasses, and also a number of fungi. Ancient Latin gutta means "a drop of fluid", whence modern botany formed the word guttation to designate that a plant exudes drops of fluid onto the outer surface of the plant, when the source of the fluid is inside the plant. Guttation happens in a variety of plant species.

Water potential is the potential energy of water per unit volume relative to pure water in reference conditions. Water potential quantifies the tendency of water to move from one area to another due to osmosis, gravity, mechanical pressure and matrix effects such as capillary action. The concept of water potential has proved useful in understanding and computing water movement within plants, animals, and soil. Water potential is typically expressed in potential energy per unit volume and very often is represented by the Greek letter ψ.

<span class="mw-page-title-main">Wilting</span> Reduced plant functioning caused by dehydration

Wilting is the loss of rigidity of non-woody parts of plants. This occurs when the turgor pressure in non-lignified plant cells falls towards zero, as a result of diminished water in the cells. Wilting also serves to reduce water loss, as it makes the leaves expose less surface area. The rate of loss of water from the plant is greater than the absorption of water in the plant. The process of wilting modifies the leaf angle distribution of the plant towards more erectophile conditions.

<span class="mw-page-title-main">Soil moisture</span> Water content of the soil

Soil moisture is the water content of the soil. It can be expressed in terms of volume or weight. Soil moisture measurement can be based on in situ probes or remote sensing methods.

In the life sciences, mass flow, also known as mass transfer and bulk flow, is the movement of fluids down a pressure or temperature gradient. As such, mass flow is a subject of study in both fluid dynamics and biology. Examples of mass flow include blood circulation and transport of water in vascular plant tissues. Mass flow is not to be confused with diffusion which depends on concentration gradients within a medium rather than pressure gradients of the medium itself.

Moisture stress is a form of abiotic stress that occurs when the moisture of plant tissues is reduced to suboptimal levels. Water stress occurs in response to atmospheric and soil water availability when the transpiration rate exceeds the rate of water uptake by the roots and cells lose turgor pressure. Moisture stress is described by two main metrics, water potential and water content.

<span class="mw-page-title-main">Transpiration stream</span>

In plants, the transpiration stream is the uninterrupted stream of water and solutes which is taken up by the roots and transported via the xylem to the leaves where it evaporates into the air/apoplast-interface of the substomatal cavity. It is driven by capillary action and in some plants by root pressure. The main driving factor is the difference in water potential between the soil and the substomatal cavity caused by transpiration.

<span class="mw-page-title-main">Guard cell</span> Paired cells that control the stomatal aperture

Guard cells are specialized plant cells in the epidermis of leaves, stems and other organs that are used to control gas exchange. They are produced in pairs with a gap between them that forms a stomatal pore. The stomatal pores are largest when water is freely available and the guard cells become turgid, and closed when water availability is critically low and the guard cells become flaccid. Photosynthesis depends on the diffusion of carbon dioxide (CO2) from the air through the stomata into the mesophyll tissues. Oxygen (O2), produced as a byproduct of photosynthesis, exits the plant via the stomata. When the stomata are open, water is lost by evaporation and must be replaced via the transpiration stream, with water taken up by the roots. Plants must balance the amount of CO2 absorbed from the air with the water loss through the stomatal pores, and this is achieved by both active and passive control of guard cell turgor pressure and stomatal pore size.

<span class="mw-page-title-main">Soil-plant-atmosphere continuum</span>

The soil-plant-atmosphere continuum (SPAC) is the pathway for water moving from soil through plants to the atmosphere. Continuum in the description highlights the continuous nature of water connection through the pathway. The low water potential of the atmosphere, and relatively higher water potential inside leaves, leads to a diffusion gradient across the stomatal pores of leaves, drawing water out of the leaves as vapour. As water vapour transpires out of the leaf, further water molecules evaporate off the surface of mesophyll cells to replace the lost molecules since water in the air inside leaves is maintained at saturation vapour pressure. Water lost at the surface of cells is replaced by water from the xylem, which due to the cohesion-tension properties of water in the xylem of plants pulls additional water molecules through the xylem from the roots toward the leaf.

Ecophysiology, environmental physiology or physiological ecology is a biological discipline that studies the response of an organism's physiology to environmental conditions. It is closely related to comparative physiology and evolutionary physiology. Ernst Haeckel's coinage bionomy is sometimes employed as a synonym.

A xerophyte is a species of plant that has adaptations to survive in an environment with little liquid water. Examples of xerophytes include cacti, pineapple and some gymnosperm plants. The morphology and physiology of xerophytes are adapted to conserve water during dry periods. Some species called resurrection plants can survive long periods of extreme dryness or desiccation of their tissues, during which their metabolic activity may effectively shut down. Plants with such morphological and physiological adaptations are said to be xeromorphic. Xerophytes such as cacti are capable of withstanding extended periods of dry conditions as they have deep-spreading roots and capacity to store water. Their waxy, thorny leaves prevent loss of moisture.

<span class="mw-page-title-main">Photosynthesis system</span> Instruments measuring photosynthetic rates

Photosynthesis systems are electronic scientific instruments designed for non-destructive measurement of photosynthetic rates in the field. Photosynthesis systems are commonly used in agronomic and environmental research, as well as studies of the global carbon cycle.

Water-use efficiency (WUE) refers to the ratio of plant biomass to water lost by transpiration, can be defined either at the leaf, at the whole plant or a population/stand/field level:

<span class="mw-page-title-main">Absorption of water</span> Life process in plants

In higher plants water and minerals are absorbed through root hairs which are in contact with soil water and from the root hairs zone a little the root tips.

Stomatal conductance, usually measured in mmol m−2 s−1 by a porometer, estimates the rate of gas exchange and transpiration through the leaf stomata as determined by the degree of stomatal aperture.

Homoiohydry is the capacity of plants to regulate, or achieve homeostasis of, cell and tissue water content. Homoiohydry evolved in land plants to a lesser or greater degree during their transition to land more than 500 million years ago, and is most highly developed in the vascular plants. It is the consequence of a suite of morphological innovations and strategies that enable plant shoots exploring aerial environments to conserve water by internalising the gas exchange surfaces, enclosing them in a waterproof membrane and providing a variable aperture control mechanism, the stomatal guard cells, which regulate the rates of water transpiration and CO2 exchange. In vascular plants, water is acquired from the soil by roots and transported via the xylem to aerial portions of the plant. Water evaporation from the aerial surfaces of the plant is controlled by a waterproof covering of cuticle. Gas exchange with the atmosphere is controlled by stomata, which can open and close to control water loss, and diffusion of carbon dioxide to the chloroplasts takes place in intercellular spaces between chlorenchyma cells in the stem or in the mesophyll tissue of the leaf.

Transpirational cooling is the cooling provided as plants transpire water. Excess heat generated from solar radiation is damaging to plant cells and thermal injury occurs during drought or when there is rapid transpiration which produces wilting. Green vegetation contributes to moderating climate by being cooler than adjacent bare earth or constructed areas. As plant leaves transpire they use energy to evaporate water aggregating up to a huge volume globally every day.

References

  1. ↑ Reddy, S. M. (2007). University Botany- Iii : (Plant Taxonomy, Plant Embryology, Plant Physiology). New Age International. ISBN   978-81-224-1547-6.
  2. ↑ Runkle, Erik (September 2023). "The Importance of Transpiration". GPN Green House Product News. 33 (9): 12–13.
  3. 1 2 Sinha, Rajiv Kumar (2004). Modern Plant Physiology. CRC Press. ISBN   978-0-8493-1714-9.
  4. ↑ Bhattacharya, A. (2022-02-25). Physiological Processes in Plants Under Low Temperature Stress. Springer Nature. ISBN   978-981-16-9037-2.
  5. ↑ Cummins, Benjamin (2007). Biological Science (3rd ed.). Freeman, Scott. p. 215.
  6. ↑ Graham, Linda E. (2006). Plant Biology. Upper Saddle River, New Jersey, USA: Pearson Education, Inc. pp. 200–202. ISBN   0-13-146906-1.
  7. ↑ Taiz, Lincoln (2015). Plant Physiology and Development. Sunderland, Massachusetts, USA: Sinauer Associates, Inc. p. 101. ISBN   978-1-60535-255-8.
  8. ↑ Freeman, Scott; Quillin, Kim; Allison, Lizabeth (2014). Biological Sciences: The Cell, Genetics, & Development. Boston, Massachusetts, USA: Pearson. pp. 765–766. ISBN   978-0-321-74367-1.
  9. ↑ Mellander, Per-Erik; Bishop, Kevin; Lundmark, Tomas (2004-06-28). "The influence of soil temperature on transpiration: a plot scale manipulation in a young Scots pine stand". Forest Ecology and Management. 195 (1): 15–28. doi:10.1016/j.foreco.2004.02.051. ISSN   0378-1127.
  10. ↑ Martin, J.; Leonard, W.; Stamp, D. (1976), Principles of Field Crop Production (3rd ed.), New York: Macmillan Publishing Co., ISBN   978-0-02-376720-3
  11. ↑ Jasechko, Scott; Sharp, Zachary D.; Gibson, John J.; Birks, S. Jean; Yi, Yi; Fawcett, Peter J. (3 April 2013). "Terrestrial water fluxes dominated by transpiration". Nature. 496 (7445): 347–50. Bibcode:2013Natur.496..347J. doi:10.1038/nature11983. PMID   23552893. S2CID   4371468.
  12. ↑ Evaristo, Jaivime; Jasechko, Scott; McDonnell, Jeffrey J. (2015-09-03). "Global separation of plant transpiration from groundwater and streamflow". Nature. 525 (7567): 91–94. Bibcode:2015Natur.525...91E. doi:10.1038/nature14983. ISSN   0028-0836. PMID   26333467. S2CID   4467297.
  13. ↑ Bowen, Gabriel (2015-09-03). "Hydrology: The diversified economics of soil water". Nature. 525 (7567): 43–44. Bibcode:2015Natur.525...43B. doi:10.1038/525043a. ISSN   0028-0836. PMID   26333464. S2CID   205086035.
  14. ↑ Ingram, David S.; Vince-Prue, Daphne; Gregory, Peter J. (2008-04-15). Science and the Garden: The Scientific Basis of Horticultural Practice. John Wiley & Sons. ISBN   978-0-470-99533-4.
  15. ↑ Zhang, Yong-Jiang (December 2016). "Reversible Leaf Xylem Collapse: A Potential "Circuit Breaker" against Cavitation". Plant Physiology. 172 (4): 2261–2274. doi:10.1104/pp.16.01191. PMC   5129713 . PMID   27733514.
  16. ↑ Hochberg, Uri (June 2017). "Stomatal Closure, Basal Leaf Embolism, and Shedding Protect the Hydraulic Integrity of Grape Stems". Plant Physiology. 174 (2): 764–775. doi:10.1104/pp.16.01816. PMC   5462014 . PMID   28351909.
  17. 1 2 Holbrook, Michele (May 2001). "In Vivo Observation of Cavitation and Embolism Repair Using Magnetic Resonance Imaging". Plant Physiology. 126 (1): 27–31. doi:10.1104/pp.126.1.27. PMC   1540104 . PMID   11351066.
  18. ↑ Tiaz, Lincoln (2015). Plant Physiology and Development. Massachusetts: Sinauer Associates, Inc. p. 63. ISBN   978-1605352558.
  19. ↑ Forbes, James C.; Watson, Drennan (1992-08-20). Plants in Agriculture. Cambridge University Press. ISBN   978-0-521-42791-3.
  20. ↑ Ellison, David; Morris, Cindy E.; Locatelli, Bruno; Sheil, Douglas; Cohen, Jane; Murdiyarso, Daniel; Gutierrez, Victoria; Noordwijk, Meine van; Creed, Irena F.; Pokorny, Jan; Gaveau, David; Spracklen, Dominick V.; Tobella, Aida Bargués; Ilstedt, Ulrik; Teuling, Adriaan J. (2017-03-01). "Trees, forests and water: Cool insights for a hot world". Global Environmental Change. 43: 51–61. doi: 10.1016/j.gloenvcha.2017.01.002 . ISSN   0959-3780.
  21. ↑ Pokorny, Jan (2019-01-01), "Evapotranspiration☆", in Fath, Brian (ed.), Encyclopedia of Ecology (Second Edition), Oxford: Elsevier, pp. 292–303, ISBN   978-0-444-64130-4 , retrieved 2022-11-21
This page is based on this Wikipedia article
Text is available under the CC BY-SA 4.0 license; additional terms may apply.
Images, videos and audio are available under their respective licenses.