Resumo

VILLANUEVA-DIAZ, José et al. Five centuries of dendrochronological history of the Montezuma cypress (Taxodium mucronatum Ten.) at the El Contador park, San Salvador Atenco, Estado de México. Agrociencia [online]. 2014, vol.48, n.7, pp.725-737. ISSN 2521-9766.

The reconstruction of climatic variability by means of tree rings is a technique that makes it possible to study climate and tree growth of the past. In order to recover dendroclimatic information in the El Contador park, San Salvador Atenco, Estado de Mexico, analyses were made of Montezuma cypress (Taxodium mucronatum Ten.) remnants of the XV century and wood cores of live trees in the area of influence of the park. The samples were analyzed with standard dendrochronological techniques, for which codating was statistically validated among sections and wood cores. The correlation with climatic variables was based on rainfall records of climatic stations in the vicinity of the study site. The chronology of the El Contador park (PCO) was compared with those of Chapultepec park, Mexico City (PCHA), and Amealco, Querétaro (AMQ), to identify extreme events in common. Total ring width is explained by the precipitation of January to June; its reduction of 55 %, from 225 to 100 mm after 1985, contributed to the 85 % reduction of growth in the basal area. It was confirmed that the trees of the park are of the period of Nezahualcoyotl (1402-1472) and their disappearance has been gradual. This elimination shows significant correlation with the depletion of the groundwater of the Valley of Mexico. The correlation among the PCO, PCHA and AMQ chronologies was not significant. In the first case, there was influence of the complementary irrigations to the trees and the climatic difference among localities in the second case. The PCO dendrochronological series showed the climatic variability of the area of influence of the Ex Lake of Texcoco and the radial growth of Montezuma cypresses. The information is relevant for the conservation of this species in its natural surroundings and in plantations with aesthetic or pharmaceutical purposes, as well as for ecological restoration and historic value.

Palavras-chave : Growth rings; long-living trees; dendroclimatology; Montezuma cypress; climatic variability.

        · resumo em Espanhol     · texto em Espanhol     · Espanhol ( pdf )