Climatic response of pinus oocarpa schiede ex schetol in the “la primavera” forest, jalisco

Abstract

The Bosque la Primavera (BLP) is a natural preserve that provides environmental services for the metropolitan area of Guadalajara. Human activities, however, have altered its ecological stability. The objective was to analyze the interannual climate variability of dominant conifer Pinus oocarpa, a climate-sensitive species. Earlywood (EWI), latewood (LWI), and ring-width (RWI) chronologies 165 years in length (1850-2014) were developed for the BLP. The residual EWI chronology had a significant association (r = 0.775, p < 0.000) with seasonal October-May rainfall from neighbor weather stations, and a negative but significant response with January-June mean maximum temperature (r =-0.622, p < 0.000). The association between EWI and precipitation was used to build a linear model to reconstruct seasonal rainfall. The most severe and prolonged drought in the reconstruction took place from 1909 to 1925, but additional dry periods were present, i.e., 1850´s, 1890´s, 1950´s, 1990´s, and 2000´s. Most of these droughts have been observed in previous reconstructions for the region, suggesting the influence of atmospheric circulatory patterns such as ENSO. The rise in maximum temperature for the last three decades in the Guadalajara metropolitan area has induced a radial growth decrease of P. oocarpa, probably triggered by an increase in greenhouse gases. Increased maximum temperatures and reduced growth of the species is threatening its ecological stability and may put in risk the provision of vital environmental services for this metropolitan area.