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TDR Technique for Estimating the Intensity of Evapotranspiration of Turfgrasses.

Janik G, Wolski K, Daniel A, Albert M, Skierucha W, Wilczek A, Szyszkowski P, Walczak A - ScientificWorldJournal (2015)

Bottom Line: Those parameters are the temperature and the volumetric moisture of soil at the depth of 2.5 cm.Evapotranspiration has the character of a modified logistic function with empirical parameters.It assumes the form ETR(θ (2.5 cm), T (2.5 cm)) = A/(1 + B · e (-C · (θ (2.5 cm) · T (2.5 cm)), where: ETR(θ (2.5 cm), T (2.5 cm)) is evapotranspiration [mm · h(-1)], θ (2.5 cm) is volumetric moisture of soil at the depth of 2.5 cm [m(3) · m(-3)], T (2.5 cm) is soil temperature at the depth of 2.5 cm [°C], and A, B, and C are empirical coefficients calculated individually for each of the grass species [mm · h(1)], and [-], [(m(3) · m(-3) · °C)(-1)].

View Article: PubMed Central - PubMed

Affiliation: Institute of Environmental Protection and Development, Wrocław University of Environmental and Life Sciences, Plac Grunwaldzki 24, 50-363 Wrocław, Poland.

ABSTRACT
The paper presents a method for precise estimation of evapotranspiration of selected turfgrass species. The evapotranspiration functions, whose domains are only two relatively easy to measure parameters, were developed separately for each of the grass species. Those parameters are the temperature and the volumetric moisture of soil at the depth of 2.5 cm. Evapotranspiration has the character of a modified logistic function with empirical parameters. It assumes the form ETR(θ (2.5 cm), T (2.5 cm)) = A/(1 + B · e (-C · (θ (2.5 cm) · T (2.5 cm)), where: ETR(θ (2.5 cm), T (2.5 cm)) is evapotranspiration [mm · h(-1)], θ (2.5 cm) is volumetric moisture of soil at the depth of 2.5 cm [m(3) · m(-3)], T (2.5 cm) is soil temperature at the depth of 2.5 cm [°C], and A, B, and C are empirical coefficients calculated individually for each of the grass species [mm · h(1)], and [-], [(m(3) · m(-3) · °C)(-1)]. The values of evapotranspiration calculated on the basis of the presented function can be used as input data for the design of systems for the automatic control of irrigation systems ensuring optimum moisture conditions in the active layer of lawn swards.

No MeSH data available.


Related in: MedlinePlus

Dynamics of volumetric moisture as information on evapotranspiration; θji  (θjf) is volumetric moisture in jth layer at the initial (final) moment [m3·m−3], θ1,2,3i  (f) is volume of water in layers 1, 2, and 3 at the initial (final) moment [m3], ETRΔt is evapotranspiration [mm·h−1], E2Δt  (E3Δt) is unit intensity of water flux between layers 1 and 2 (2 and 3) [mm·h−1], F is surface area of soil column cross section [m2], Vj is volume of jth layer [m3], Δt is time step [h], ti  (tf) is initial (final) moment, and H is soil layer height [m].
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fig1: Dynamics of volumetric moisture as information on evapotranspiration; θji  (θjf) is volumetric moisture in jth layer at the initial (final) moment [m3·m−3], θ1,2,3i  (f) is volume of water in layers 1, 2, and 3 at the initial (final) moment [m3], ETRΔt is evapotranspiration [mm·h−1], E2Δt  (E3Δt) is unit intensity of water flux between layers 1 and 2 (2 and 3) [mm·h−1], F is surface area of soil column cross section [m2], Vj is volume of jth layer [m3], Δt is time step [h], ti  (tf) is initial (final) moment, and H is soil layer height [m].

Mentions: It was assumed that the evapotranspiration of selected turfgrass species can be calculated on the basis of a function whose domain is only two values: temperature and volumetric moisture of the surface layer of soil. The function can be determined on the basis of an experiment. The values that constitute its domain are relatively easy to measure, while the evapotranspiration can be calculated using the time-domain reflectometry (TDR), as illustrated in Figure 1.


TDR Technique for Estimating the Intensity of Evapotranspiration of Turfgrasses.

Janik G, Wolski K, Daniel A, Albert M, Skierucha W, Wilczek A, Szyszkowski P, Walczak A - ScientificWorldJournal (2015)

Dynamics of volumetric moisture as information on evapotranspiration; θji  (θjf) is volumetric moisture in jth layer at the initial (final) moment [m3·m−3], θ1,2,3i  (f) is volume of water in layers 1, 2, and 3 at the initial (final) moment [m3], ETRΔt is evapotranspiration [mm·h−1], E2Δt  (E3Δt) is unit intensity of water flux between layers 1 and 2 (2 and 3) [mm·h−1], F is surface area of soil column cross section [m2], Vj is volume of jth layer [m3], Δt is time step [h], ti  (tf) is initial (final) moment, and H is soil layer height [m].
© Copyright Policy - open-access
Related In: Results  -  Collection

Show All Figures
getmorefigures.php?uid=PMC4581558&req=5

fig1: Dynamics of volumetric moisture as information on evapotranspiration; θji  (θjf) is volumetric moisture in jth layer at the initial (final) moment [m3·m−3], θ1,2,3i  (f) is volume of water in layers 1, 2, and 3 at the initial (final) moment [m3], ETRΔt is evapotranspiration [mm·h−1], E2Δt  (E3Δt) is unit intensity of water flux between layers 1 and 2 (2 and 3) [mm·h−1], F is surface area of soil column cross section [m2], Vj is volume of jth layer [m3], Δt is time step [h], ti  (tf) is initial (final) moment, and H is soil layer height [m].
Mentions: It was assumed that the evapotranspiration of selected turfgrass species can be calculated on the basis of a function whose domain is only two values: temperature and volumetric moisture of the surface layer of soil. The function can be determined on the basis of an experiment. The values that constitute its domain are relatively easy to measure, while the evapotranspiration can be calculated using the time-domain reflectometry (TDR), as illustrated in Figure 1.

Bottom Line: Those parameters are the temperature and the volumetric moisture of soil at the depth of 2.5 cm.Evapotranspiration has the character of a modified logistic function with empirical parameters.It assumes the form ETR(θ (2.5 cm), T (2.5 cm)) = A/(1 + B · e (-C · (θ (2.5 cm) · T (2.5 cm)), where: ETR(θ (2.5 cm), T (2.5 cm)) is evapotranspiration [mm · h(-1)], θ (2.5 cm) is volumetric moisture of soil at the depth of 2.5 cm [m(3) · m(-3)], T (2.5 cm) is soil temperature at the depth of 2.5 cm [°C], and A, B, and C are empirical coefficients calculated individually for each of the grass species [mm · h(1)], and [-], [(m(3) · m(-3) · °C)(-1)].

View Article: PubMed Central - PubMed

Affiliation: Institute of Environmental Protection and Development, Wrocław University of Environmental and Life Sciences, Plac Grunwaldzki 24, 50-363 Wrocław, Poland.

ABSTRACT
The paper presents a method for precise estimation of evapotranspiration of selected turfgrass species. The evapotranspiration functions, whose domains are only two relatively easy to measure parameters, were developed separately for each of the grass species. Those parameters are the temperature and the volumetric moisture of soil at the depth of 2.5 cm. Evapotranspiration has the character of a modified logistic function with empirical parameters. It assumes the form ETR(θ (2.5 cm), T (2.5 cm)) = A/(1 + B · e (-C · (θ (2.5 cm) · T (2.5 cm)), where: ETR(θ (2.5 cm), T (2.5 cm)) is evapotranspiration [mm · h(-1)], θ (2.5 cm) is volumetric moisture of soil at the depth of 2.5 cm [m(3) · m(-3)], T (2.5 cm) is soil temperature at the depth of 2.5 cm [°C], and A, B, and C are empirical coefficients calculated individually for each of the grass species [mm · h(1)], and [-], [(m(3) · m(-3) · °C)(-1)]. The values of evapotranspiration calculated on the basis of the presented function can be used as input data for the design of systems for the automatic control of irrigation systems ensuring optimum moisture conditions in the active layer of lawn swards.

No MeSH data available.


Related in: MedlinePlus