there are threeparts to this question: how to read rings from a tree, how to sample tree growth to analyze potential carbon sequestration, and how to convert this into sequestered carbon units.

I will skip for the moment on part two, but you need to think carefully about what trees you need to sample (species, age, isolated or in a forest...) and consider natural variability by a meaningful sampling design (repetitions, stratification, etc).

part three is carried out by estimating the volume increment from the radial increment: you must know the tree dimensions and have some function that converts diameter to volume (also taking into account the bark thickness of the bole) and volume to dry biomass. If you do this over time you will get an estimate of aboveground carbon stocked: carbon in roots, small branches, leaves, and possibly the soil will need to be estimated and added later.

part one: in summary, you need to extract tree rings (best if two, in orthogonal directions across the stem, avoiding any macroscopic growth irregularities) with an increment borer, or obtain a cross-section (destructive sampling) at a standard height (130 cm usually). 

Then you prepare the core (glued to a support) or cross-section by sanding with progressively finer paper, then you count and measure increment rings (usually to the nearest 1/100 mm)  under a microscope attached to some reading device (eg a LINTAB). 

Age is estimated by counting rings, plus adding your estimate of missing pith rings, plus time required for the tree to get to sampling height. 

A correct attribution of ring widths to each year, however, must be done by cross-dating your ringwidth series against other trees in the area or known chronologies. 

Thanks Giorgio. Yes, species choice will be done after following the previous research output. I will go for taking cores from 20 individual tree species over 20 years old. The stratification will be based on rainfall gradient and the ecosystem from homestead agroforestry.  Yes, I will go for above ground biomass estimation then gradually carbon stock. I will follow the established method for that.

LINTAB device..........yes, I think it would be nice to measure tree ring width. I think fro cross dating 20 cores will be enough. Begging your suggestions.

Which method you prefer for estimating biomass calculation, including litterfall and foilage biomass  and to convert into carbon content?

I am seeking your suggestions.

Hi Nirmol,

I cheap device for measuring is the Corecorder http://www.cybis.se/forfun/dendro/ it´s about 70U$ together with a scanner eg. Epson V370 https://www.epson.de/products/scanners/consumer-scanners/perfection-v370-photo for ca 150U$ you have a very good measuring unite. Much cheaper than LINTAB and more practical because you are working with digital images. Deleating and inserting of rings is faster.

Crossdating can be done in R (dplR) or Cofecha

Hi Stefan,

So many thanks. This machine was fully unknown to me. It is wonderful as it is too cheap and good. Can you please give me some detail of dpIR or Cofecha?

Thanks once again.

Hi,

I also recommend CooRecorder and basically any flatbed scanner (higher resolution is better). It is worth mentioning that actually you are buying packed of softwares from Cybis. It is called Cdendro and includes two programs: CooRecorder, which is dedicated to measure ring widths and also other parameters and CDendro which is tool to test the quality of measurements, crossdate and build chronology.  It is easier to work using this couple of programs because the file formats is identical. I recommend using Cofecha, which is great tool or/and dplR only as a next step.

Good luck and don't hesitate to ask about details if necessary!

Thanks Kaczka. Do you have some reference on Cofecha?

Dear Nirmol,

I recommend you to check this references: the first one for the COFECHA program and the second one for the basic concepts for dendrochronological studies (including COFECHA).

GRISSINO-MAYER, H.D. 2001. Evaluating crossdating accuracy: a manual and tutorial for the computer program COFECHA. Tree-Ring Res. 57: 205–221.

Speer, J.H. 2010. Fundamentals of Tree-Ring Research. The University of Arizona Press. 324p.

Best wishes,

Stella.

Thanks Stella. Indeed your references will help me a lot.