Skip to Main Content
Nitrogen and sulfur desposition and forest nutrient status in the valley of MexicoAuthor(s): Mark E. Fenn; L.I. De Baur; A. Quevedo-Nolasco; C. Rodriguez-Frausto
Source: Water, Air, and Soil Pollution 113:155-174
Publication Series: Miscellaneous Publication
PDF: View PDF (144 KB)
DescriptionMexico City experiences some of the most severe air pollution in the world. Ozone injury has been documented in sensitive tree species in urban and forested areas in the Valley of Mexico. However, little is known of the levels of other atmospheric pollutants and their ecological effects on forests in the Valley of Mexico. In this study bulk throughfall deposition of inorganic nitrogen (N) and sulfur (S) was measured for one year at a forested site upwind (east) and downwind (southwest) of Mexico City. Edaphic and plant (Pinus hartwegii Lindl.) indicators of N and S nutrient status were also measured. Streamwater NO3- and SO2−4 concentrations were also determined as an indicator of watershed-level N and S loss. Annual bulk throughfall deposition of inorganic N and S at the high-pollution forested site 23 km southwest of Mexico City (Desierto de los Leones National Park; DL) was 18.5 and 20.4 kg ha−1. Values for N and S deposition at Zoquiapan (ZOQ), a relatively low-pollution site 53 km east of Mexico City, were 5.5 and 8.8 kg ha−1 yr−1. Foliar concentrations of N, foliar N:P and C:N ratios, extractable soil NO−3 , and streamwater NO3- concentrations indicate that the forest at DL is N enriched, possibly as a result of chronic N deposition. Sulfur concentrations in current-year foliage were also slightly greater at DL than at ZOQ, but S concentrations in one-year-old foliage were not statistically different between the two sites. Streamwater concentrations of NO3- ranged from 0.8 to 44.6 μEq L−1 at DL compared to 0.0 to 11.3 μEq L−1 at ZOQ. In summary, these findings support the hypothesis that elevated N deposition at DL has increased the level of available N, increased the N status of P. hartwegii, and resulted in export of excess N as NO3- in streamwater.
- You may send email to email@example.com to request a hard copy of this publication.
- (Please specify exactly which publication you are requesting and your mailing address.)
- We recommend that you also print this page and attach it to the printout of the article, to retain the full citation information.
- This article was written and prepared by U.S. Government employees on official time, and is therefore in the public domain.
CitationFenn, Mark E.; Baur, L.I. De; Quevedo-Nolasco, A.; Rodriguez-Frausto, C. 1999. Nitrogen and sulfur desposition and forest nutrient status in the valley of Mexico. Water, Air, and Soil Pollution 113:155-174
KeywordsNitrogen enrichment, nutrient ratios, streamwater nitrate, throughfall, volcanic emissions
- Throughfall and fog deposition of nitrogen and sulfur at an N-limited and N-saturated site in the San Bernardino Mountains, southern California
- Summar throughfall and winter deposition in the San Bernardino mountains in southern California
- Nitrogen deposition in California forests: a review
XML: View XML