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Shiro TSUYUZAKI
Plant community ecology / Environmental conservation

Mount Usu / Sarobetsu post-mined peatland
From left: Crater basin in 1986 and 2006. Cottongrass / Daylily

(Update on Feb. 15, 2009)

Temperatuere

[ temperature | thermal time ]

Temperature

A physical property of a system that underlies the common notions of hot and cold

absolute temperature
centigrade temperature (degrees C)
Fahrenheit temperature (degrees F)
Kelvin temperature

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Thermal time

(Black et al. 2006)

Cumulative temperature above a base temperature below which plant development (or germination) ceases, and is often calculated on a daily basis, as follows.

Tt (oC d) = Σ(((Tmax - Tmin)/2) - Tb)

where Tmax and Tmin are the daily maximum and minimum temperatures and Tb is the base temperature.
Data are plotted as the reciprocal of the duration (in days) to x% germination against the mean temperature (T). The inverse of duration (1 d-1) represents the development rate (DR). Least squares regression analysis was used for the positive linear portion of the response whereby:

DR = a1 + b1T
Tb = -a1/b1
and
Tt = 1/b1

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References

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