Tree growth is a key mechanism driving carbon sequestration in forest ecosystems. Environmental conditions are important regulators of tree growth that can vary considerably between nearby urban and rural forests. For example, trees growing in cities often experience hotter and drier conditions than their rural counterparts while also being exposed to higher levels of light, pollution, and nutrient inputs. However, the extent to which these intrinsic differences in the growing conditions of trees in urban versus rural forests influence tree growth response to climate is not well known. In this study, we tested for differences in the climate sensitivity of tree growth between urban and rural forests along a latitudinal transect in the eastern United States that included Boston, Massachusetts, New York City, New York, and Baltimore, Maryland. Using dendrochronology analyses of tree cores from 55 white oak trees (
White oak and red maple foliar chemistry of urban and reference forests of the eastern US
Foliar chemistry values were obtained from two important native tree
species (white oak (Quercus alba L.) and red maple (Acer rubrum L.))
across urban and reference forest sites of three major cities in the
eastern United States during summer 2015 (New York, NY (NYC);
Philadelphia, PA; and Baltimore, MD). Trees were selected from
secondary growth oak-hickory forests found in New York, NY;
Philadelphia, PA; and Baltimore, MD, as well as at reference forest
sites outside each metropolitan area. In all three metropolitan areas,
urban forest patches and references forest sites were selected based
on the presence of red maple and white oak canopy dominant trees in
patches of at least 1.5 hectares with slopes less than 25%, and
well-drained soils of similar soil series within each metropolitan
area. Within each city, several forest patches were selected to
capture the variation in forest patch site conditions across an
individual city. All reference sites were located in protected areas
outside of the city and within intermix wildland-urban interface
landscapes, in order to target similar contexts of surrounding land
use and population density (Martinuzzi et al. 2015). Several reference
sites were selected for each city, located within the same protected
area considered representative of rural forests of the region. White
oaks were at least 38.1 cm diameter at breast height (DBH), red maples
were at least 25.4 cm DBH, and all trees were dominant or co-dominant
canopy trees. The trees had no major trunk cavities and had crown
vigor scores of 1 or 2 (less than 25% overall canopy damage; Pontius
& Hallett 2014). From early July to early August 2015, sun leaves
were collected from the periphery of the crown of each tree with
either a shotgun or slingshot for subsequent analysis to determine
differences in foliar chemistry across cities and urban vs. reference
forest site types. The data were used to invstigate whether
differences in native tree physiology occur between urban and
reference forest patches, and whether those differences are site- and
species-specific.
A complete analysis of these data can be found in:
Sonti, NF. 2019. Ecophysiological and social functions of urban forest
patches. Ph.D. dissertation. University of Maryland, College Park, MD.
166 p.
References:
Martinuzzi S, Stewart SI, Helmers DP, Mockrin MH, Hammer RB, Radeloff
VC. 2015. The 2010 wildland-urban interface of the conterminous United
States. Research Map NRS-8. US Department of Agriculture, Forest
Service, Northern Research Station: Newtown Square, PA.
Pontius J, Hallett R. 2014. Comprehensive methods for earlier
detection and monitoring of forest decline. Forest Science 60(6):
1156-1163.
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- Award ID(s):
- 1855277
- NSF-PAR ID:
- 10474639
- Publisher / Repository:
- Environmental Data Initiative
- Date Published:
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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Groffman PM, Holland E, Myrold DD, Robertson GP and Zou X (1999) Denitrification. In: Robertson GP, Bledsoe CS, Coleman DC and Sollins P (Eds) Standard Soil Methods for Long Term Ecological Research. (pp 272-290). Oxford University Press, New York Groffman PM, Pouyat RV, Cadenasso ML, Zipperer WC, Szlavecz K, Yesilonis IC,. Band LE and Brush GS. 2006. Land use context and natural soil controls on plant community composition and soil nitrogen and carbon dynamics in urban and rural forests. Forest Ecology and Management 236:177-192. Groffman, P.M., C.O. Williams, R.V. Pouyat, L.E. Band and I.C. Yesilonis. 2009. Nitrate leaching and nitrous oxide flux in urban forests and grasslands. Journal of Environmental Quality 38:1848-1860. Groffman, P.M. and R.V. Pouyat. 2009. Methane uptake in urban forests and lawns. Environmental Science and Technology 43:5229-5235. DOI: 10.1021/es803720h. Holland EA, Boone R, Greenberg J, Groffman PM and Robertson GP (1999) Measurement of Soil CO2, N2O and CH4 exchange. In: Robertson GP, Bledsoe CS, Coleman DC and Sollins P (Eds) Standard Soil Methods for Long Term Ecological Research. (pp 258-271). Oxford University Press, New York Robertson GP, Wedin D, Groffman PM, Blair JM, Holland EA, Nadelhoffer KJ and. Harris D. 1999. Soil carbon and nitrogen availability: Nitrogen mineralization, nitrification and carbon turnover. In: Standard Soil Methods for Long Term Ecological Research (Robertson GP, Bledsoe CS, Coleman DC and Sollins P (Eds) Standard Soil Methods for Long Term Ecological Research. (pp 258-271). Oxford University Press, New York Savva, Y., K. Szlavecz, R. V. Pouyat, P. M. Groffman, and G. Heisler. 2010. Effects of land use and vegetation cover on soil temperature in an urban ecosystem. Soil Science Society of America Journal 74:469-480."more » « less
