Dear Ecology list,

I'm trying to calculate the Q10 (temperature sensitivity) of decomposition
in R. I have done so in excel straight forwardly enough but I want to check
it in R.
Does anyone have any ideas how to go about this?

It is calculated as

y_T ~ a * e^(bx_T)
where y is the decomposition rate at temperature T, x_T is the temperature
and "a" and "b" are constants. "e" is the magic number (exp(1) ; 2.7183)

then

 Q10 = exp(10*b)

In excel I simply fit an exponential trend line, read off "b" from the
formula and then calculate Q10 as above. In R it seems to be a bit harder.

Ive attempted to use nls() to derive the exponent but I get a completely
different number (when it doesnt give me a singularity error). nls() doesnt
seem to like the "a" term either, as it seems to be this that generates the
singularity issue.

Does anyone know of a function, or suite of functions, for calculating Q10?

Thanks in advance,

Alan



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Email: aghaynes@gmail.com
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