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Entries in Selva Maya (23)


Eight Years Ago Today

I was in the Selva Maya of Quintana Roo putting dendrometer bands around some of the timber trees to measure growth (see Selva Maya III).  There were monkeys (Ateles geoffroyi yucatanensis) jumping around in the canopy and making a lot of noise and one landed very close to me and was checking me out. I tried to get a picture, but my camera focused on the leaves in the foreground, not the monkey in the background. [NOTE: I hate it when that happens]. 


Tree On A Ruin

White limestone, white tree (probably a Ficus sp.), cloudless blue sky, and blazing sun. Thinking of this trip to Calakmul in Campeche years ago, and how hot and dry it was, and doing all that I can to ignore the fact that it is 3° F with blustery winds in New York this morning with a wind chill of -28° F. 




Am working on a little primer for communities about measuring the growth of tropical trees, and I spent most of yesterday playing with spreadsheets. The book is largely based on the growth data collected by forestry ejidos in the Selva Maya (see Selva Maya III and Reading the Bands). Data is a bit noisy, and the relationships between size and diameter growth are not as clear as I would like (see jumble of points in the diameter/growth scattergram shown at the lower right of the computer screen). That said, the data do provide a strong estimate of the average annual growth rate of each species (inset shows that the standard errors around the mean are less than 2.0%, i.e. Mean=0.38043006 and Std. Error = 0.00620184). Mean growth estimates with standard errors as large as 10.0% are routinely used for management planning, so I am actually quite pleased with this result.

Am hoping that I can finish the primer before the end of the year. Will be in Spanish (thx, Silvia).


Other Week: Day 3

Original Post: Street Food in Chetumal
Date:February 22, 2009 at 4:23 PM
The city of Chetumal in Quintana Roo, Mexico is the entry point to the Selva Maya (see Selva MayaSelva Maya IISelva Maya III, and Selva Maya Interrupted).  Lot of delicious food available on the street at night.  The elotes smeared with mayonaise, queso fresco, and chili powder are my favorites. [NOTE: In spite of what the lady said, the chili habanero powder was - of course - killer hot.]

Tools of the Trade

We gave each of the field crews in the Selva Maya growth study (see Selva Maya III) a little plastic lunch box (available at OfficeMax in Chetumal) full of stainless steel strapping and extension springs. These items are what you need to make dendrometer bands (as shown here) to precisely measure tree growth.

A dendrometer band is custom-made for each sample tree in the field. Lot of opening and closing of the plastic lunch box, but they held up very well (thx, OfficeMax).


On The Road to NohBec

This seen in Quintana Roo, Mexico on the road to NohBec (see Radiator Cap, Patriarchand Selva Maya II). Small Mayan pyramid carefully excavated, re-constructed, and incorporated into village life. [NOTE: What a great place to graze your horse].


Is That a Pyramid?

The forests of Quintana Roo contain hundreds of unexcavated Mayan pyramids (see The Pyramid at Tres Garantias). The image above shows what these pyramids look like when you are walking through the forest reading tree bands (see Reading the Bands) and look over and see some abrupt topography in what is essentially a flat, limestone shield.

If you stop what you are doing and climb to the top of this little mountain (highly recommended), noticing all of the precisely-cut, square stones during the ascent, when you get to the top  and look out toward Guatemala, what you see - is a flat limestone shield and hundreds and hundreds of hectares of tropical forest. [NOTE: The Selva Maya is the second largest expanse of tropical forest in the New World after Amazonia].


Logging Chains

Close-up of  logging chains in the back of one of the old trucks at NohBec in the Selva Maya of Quintana Roo, Mexico (see Selva Maya, Selva Maya II, and Radiator Cap). I got some funny looks when I took this picture. 


Reading the Bands

Last March, Silvia Purata, Antonio Sierra, and I reviewed some of the dendrometer bands (see How to Make Dendrometer Bands) that we had left in the Selva Maya to measure tree growth (see Selva Maya III).  In most cases, the bands were in good condition and recording notable diameter increments. In other cases, well...[NOTE: In spite of hurricanes (see Selva Maya Interrupted), lost calipers, and various other setbacks, this research has collected an unprecedented amount of information about the growth of timber trees in the Selva Maya. Deep bows to all involved.]


Warrior's Dreams

Carefully groomed courtyard and the unfinished reconstruction of one of the pyramids at Kohunlich (see Kohunlich) in Quintana Roo.  Matsu Bashō pretty much sums it up with his haiku:

Summer grasses
All that remains
Of brave warrior's dreams