[Aztlan] deforestation in the Peten

[Bruce Rogers]

Listeros,

While this is a recent study, it has implications 
for the increase in daily temperatures and 
lowering of soil moisture with subsequent 
lowering of crop yields, increasing scarcity of 
drinking water, and diminishing forest timber and 
food resources in the Peten at the end of the 
Classic/Terminal Classic Period.  This apparently 
contributed to the subsequent demise of organized 
society during the "Maya collapse," all as a 
result of deforestation.

Cheers,
Bruce Rogers, earth scientist on a good, wet day


Impact of deforestation on regional surface 
temperatures and moisture in the Maya lowlands of 
Guatemala

Vani Starry Manoharan and Ronald M. Welch
Department of Atmospheric Sciences, University of 
Alabama in Huntsville, Huntsville, Alabama, USA

Robert O. Lawton
Department of Biological Sciences, University of 
Alabama in Huntsville, Huntsville, Alabama, USA

The Petén basin of Guatemala is a region in 
Mesoamerica experiencing extensive deforestation. 
Twelve 30 x 30 km2 forested, deforested and 
partially deforested habitats are selected to 
compare changes in surface temperature, 
Normalized  Difference Vegetation Index (NDVI) 
and soil moisture parameters derived from MODIS 
satellite data during the dry and wet seasons 
from 2000 to 2008.

During the wet season surface temperatures, soil 
moisture, and NDVI values have similar values in 
forested  and deforested regions. During the dry 
season, deforested regions tend to be 4-8°C 
warmer than nearby forested regions, along  with 
significantly lower values of NDVI and soil 
moisture.

From 2000 to 2008, the partially deforested 
regions became progressively  warmer during the 
dry season, and both NDVI and soil moisture 
values approached those of the deforested 
regions. A supervised classification revealed 
that three partially deforested regions contained 
17.7%, 12.9% and 13.4% forests in 2000, 
decreasing  to 2.9%, 8.3% and 4.7%, respectively, 
in 2008. Overall, partially forested regions in 
the Petén region decreased in forest  cover by 
9.3% from 2000 to 2008, while there has been a 
0.33% per year deforestation rate over the entire 
Petén basin.

  Received 3 September  2009;  accepted 8 October 
2009;  published 4 November  2009.
Citation: Manoharan, V. S., R. M. Welch, and R. 
O. Lawton (2009), Impact of deforestation on 
regional surface temperatures and moisture in the 
Maya lowlands of Guatemala,  Geophys. Res. 
Lett.,  36, L21701, doi:10.1029/2009GL040818.