"How much forest is crushed to pull out one tree?"I've hired a "tecnico" from the ejido, Valentin Canul, who I noticed last week had an uncanny ability to remember plant names. Well, uncanny from my perspective anyway, here its just a little better than normal.
Valentin is a local tecnico, meaning he was trained by the ejido union, Organizacion de Ejidos Productores Forestales de la Zona Maya (OEPF) to do tree inventories and collect forestry data. Since the hurricane hit, he's been working on a tree inventory for the Ejido, a requirement before new logging permits are issued. He's not paid for this work, but he knows there won't be a job for him or others in the ejido if they don't get new permits.
He explained a little bit of the methodology* for the tree surveys while we were trying to figure out how to answer my question. The ejido's property is divided into a series of transects, or straight lines across the land.
Starting on the transect line and moving away from it in both directions, Valentin or another tecnico measures all seedlings (over 5 cm tall) for the first 10 meters. From the 10 meter line, he measures only the big stuff, everything larger than 20 cm measured at the height of his chest.** From the 25 meter line to the 100 meter line, he only measures the commercially valuable species.With this (rather impressive) amount of information, the government and OEPF can gain an accurate picture from which to decide how much wood can be harvested each year. Valentin says they have enough information right now for the next 5 years in their 25 year cycle.
In order to make my measurements of destruction fit into OEPF's methods, I used their size classes and worked out the methodology with Valentin. We decided to follow the Treefarmer, which is a sort of cross between a bulldozer and a tractor used to clear a path to a tree and pull out the log. The Treefarmer is the most destructive part of the logging operation, and its also the part we're hoping can be eliminated once the microsawmills take over and people are pulling boards rather than logs out of the forest.
We spent the day behind the Treefarmer measuring 30 meters with our measuring tape before stopping to count all of the plants in our sample. The sample was 1 meter long and as wide as the obvious impact of the tree farmer, which varied from 4 meters to 7 meters. Valentin identified all the plants, gave me their names in Spanish or Mayan (whichever one was shorter) and I simply wrote them down. It felt like Valentin could have done this on his own, but I did insist on counting all the plants, even the tiny ones, which might not have happened if it was just him.
Turns out, it took almost half a hectare (1.2 acres) of Treefarmer destruction to get 16 trees, about 0.03 hectares (0.07 acres) per tree. Thats a half hectare of impact and soil compaction, but nobody knows how well the Treefarmer trails recover after they've been used. Of course, my sample is also really low because I was only able to get out there and measure this for one day, so its best you think of it as a detailed anecdote.
Attached is my data, categorized in Spanish. Checka checka checka if you think its cool-
Data
--
* I realize this is a really geeky article, but I always wish I could find stuff like this on the internet so here it is! Enjoy it, rising forestry geeks.
** This measurement, called Diameter at Breast Height or DBH, is a standard measurement in forestry that has survived the ages despite its innate subjectivity as to what "Breast Height" is.
No comments:
Post a Comment