| the carbon charging of pines at the climatic treeline: a global comparison. | the carbon charging of pines across the treeline ecotone of three different climatic zones (mexico 19 degrees n pinus hartwegii, swiss alps 46 degrees n p. cembra and northern sweden 68 degrees n p. sylvestris) was analyzed, to test whether a low-temperature-driven carbon shortage can explain high-elevation tree limits, and whether the length of the growing season affects the trees' carbon balance. we quantified the concentrations of non-structural carbohydrates (nsc) and lipids (acylglycerols) ... | 2003 | 12647099 |
| a 400-year tree-ring chronology from the tropical treeline of north america. | high-elevation sites in the tropics may be particularly sensitive to rapid climate change. by sampling treeline populations, i have developed the first extensive (> 300 years) tree-ring chronology in tropical north america. the site is nevado de colima, at the western end of the mexican neovolcanic belt, and the species studied is mexican mountain pine (pinus hartwegii). despite past logging in the area, 300 to 500-year old pines were found at 3600-3700 m elevation, about 300 m below the present ... | 2001 | 11436664 |
| chloroplast evolution in the pinus montezumae complex: a coalescent approach to hybridization. | this study addresses the evolutionary history of the chloroplast genomes of two closely related pine species, pinus hartwegii lindl. and p. montezumae lamb (subsect. ponderosae) using coalescent theory and some of the statistical tools that have been developed from it during the past two decades. pinus hartwegii and p. montezumae are closely related species in the p. montezumae complex (subsect. ponderosae) of mexico and central america. pinus hartwegii is a high elevation species, whereas p. mo ... | 2000 | 11005290 |
| a review of ozone-induced effects on the forests of central mexico. | the first report on oxidant-induced plant damage in the valley of mexico was presented over 30 years ago. ozone is known to occur in the mexico city metropolitan area and elsewhere as the cause of chlorotic mottling on pine needles that are 2 years old or older as observed in 1976 on pinus hartwegii and pinus leiophylla. visible evidences for the negative effects of ozone on the vegetation of central mexico include foliar injury expressed as chlorotic mottling and premature defoliation on pines, ... | 2007 | 17478022 |