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seen Mar 10 at 16:18

Nov
19
comment If I built a concrete pool, would it ever contain fish?
@goodgravy algae don't thrive on organic matter, they thrive on mineral nutrients, N and P in particular. Ca is important but rarely limiting.
Nov
18
comment Does preservation in ethanol alter leaf litter mass?
This paper implies the EtOH extractable fraction in willow leaf litter is small ~2% download.springer.com/static/pdf/61/… but this will vary by species (eg pine tar). Again, this effect can be measured on samples similar to yours.
Nov
18
comment Does preservation in ethanol alter leaf litter mass?
This sounds like something that would be straightforward to test empirically. As a bonus, any effect of EtOH on your samples (bias) could (possibly) be quantified and accounted for, especially if the effect is small. The questions you are asking will inform how best to do this. But I do suspect EtOH might dissolve some hydrophobic compounds in the coarse fraction. Maybe try evaporating it first and adding water. Not ideal, but likely more informative than throwing samples out!
Nov
18
comment Does preservation in ethanol alter leaf litter mass?
How do you plan to separate the POM from the rest of the sample?
Nov
18
comment If I built a concrete pool, would it ever contain fish?
@goodgravy your scenario requires a healthy dose of nutrients
Nov
18
comment Shortest route for a Nitrogen atom from fossil fuel to a protein in your body?
Fossil fuel -combustion-> NOx -deposition-> plant -> person
Nov
18
comment Energy flow in an ecosystem
What makes you think there are mistakes?
Jun
10
comment Measuring sugar content of a tree
@AlanBoyd Moorhead and Sinsabaugh 2006 "Theoretical Model of Litter Decay and Microbial Interaction" gives a good summary (see Part 2: Lignin x cellulose controls).
Jun
9
comment Measuring sugar content of a tree
@alan even if lignin degraders breakdown lignin and can utilize some of the products, I don't think the lignin itself results in a net benefit to the fungus (because ligninases are so costly to build) it is the cellulose inside the lignin matrix that they are after.
Jun
6
comment Measuring sugar content of a tree
The soluble carbohydrate can get the mushrooms off to a good start, but it is the cellulose that will be most important for production. Another reason people innoculate logs in winter is because there are fewer spores from competitors in the air, and less work to be done in the field (for farmers).
Mar
7
comment Fibonacci sequence in nature, truth or just wishful thinking?
The pattern forming processes generate a fibonnachi pattern, but there are other processes that occur as well.
Mar
7
comment How is instinctual information encoded?
+1 sound good, do you have any primary references?
Sep
5
comment What is the Edward O. Wilson fuss about?
How is the fact that group selection does not hold in theory reconcile with observations / experimental tests? Is there another explanation for inherited religious, social, or political groups?
Sep
5
comment What is the Edward O. Wilson fuss about?
I started reading David Sloan Wilson's work on group selection a decade ago and am surprised that the field still has such a reluctance to move on.
Sep
5
comment From which ancestor species did humans inherit orgasm?
-1 using the term "Invented" makes this question nonsensical.
Jun
19
comment Can I estimate leaf temperature from air temperature? What other information would be required?
@nico perhaps because the error of measurement is >= than the error introduced by this assumption (e.g. if the delta-T is ~1-2C the error might be on the order of 10%). If there is a reference, I haven't seen it cited, and this assumption is made ~ 10% of the time - usually in older papers before thermocouples on the leaf surface at the time of measurement were integrated into standard equipment.
Jun
19
comment Features in individuals causing high population variation
The term "striving" and the phrase "the individual should strive" raise concerns like those in the comment by @DQdlM. I would suggest re-phrasing the question.
Jun
12
comment Compare and contrast “Rubisco activity” and “assimilation rate” (is there a difference, and if so, what is it)?
more or less in general. It seems like a less direct measure (since the sugar pool presumably has losses to respiration as well as inputs from assimilation). It also seems more difficult in general, although perhaps less expensive.
Jun
12
comment What are the units of Q10 (temperature sensitivity)?
how do you calculate k, are the curves in the figure something like e^{-kt}?
Jun
12
comment Compare and contrast “Rubisco activity” and “assimilation rate” (is there a difference, and if so, what is it)?
This is a useful answer, and it does answer my question. However, I was not familiar with measuring assimilation using 14C-CO2. Almost every leaf-level measurement I have found in the literature has been measured with a LI-6400, which measures exchange of [CO2] and [H2O] between the leaf and atmosphere. In what cases is 14C used?