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Indirectly - by measuring the distance the water level drops in the graduated tube over a measured length of time. It is assumed that this is due to the cutting taking in water which in turn is necessary to replace an equal volume of water lost by transpiration. Directly - by measuring the reduction in mass of the potometer over a period of time.
Chlorophyll fluorometers are designed to measure variable fluorescence of photosystem II. This variable fluorescence can be used to measure the level of plant stress. The most commonly used protocols include those aimed at measuring the photosynthetic efficiency of photosystem II, both in the light (ΔF/Fm') and in a dark-adapted state (Fv/Fm ...
It is also known as available water content (AWC), profile available water (PAW) [2] or total available water (TAW). The concept, put forward by Frank Veihmeyer and Arthur Hendrickson, [ 3 ] assumed that the water readily available to plants is the difference between the soil water content at field capacity ( θ fc ) and permanent wilting point ...
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.
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: leaf level : photosynthetic water-use efficiency (also called instantaneous water-use efficiency WUE inst), which is defined as the ratio of the rate of net CO 2 ...
The maximum amount of water that a given soil can retain is called field capacity, whereas a soil so dry that plants cannot liberate the remaining moisture from the soil particles is said to be at wilting point. [2] Available water is that which the plants can utilize from the soil within the range between field capacity and wilting point.
A water balance states that the amount water entering the soil must be equal to the amount of water leaving the soil plus the change in the amount of water stored in the soil. The water balance has four main components: infiltration of precipitation into the soil, evapotranspiration , leakage of water into deeper portions of the soil not ...
Fremitus is a vibration transmitted through the body. [1] In common medical usage, it usually refers to assessment of the lungs by either the vibration intensity felt on the chest wall (tactile fremitus) and/or heard by a stethoscope on the chest wall with certain spoken words (vocal fremitus), although there are several other types.