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dc.contributor.advisorTempler, Pamela H.en_US
dc.contributor.advisorHutyra, Lucy R.en_US
dc.contributor.authorDecina, Stephen Michaelen_US
dc.date.accessioned2018-08-29T13:49:29Z
dc.date.available2018-08-29T13:49:29Z
dc.date.issued2018
dc.identifier.urihttps://hdl.handle.net/2144/30929
dc.description.abstractWith a burgeoning population, increasing land area, and the emergence of new megacities, urban areas have the ability to alter biogeochemical cycles across great scales. Though cities are hotspots of pollution, these concentrated population centers present an opportunity to reduce the human footprint and provide a model of sustainability. Creating sustainable cities requires an understanding of urban biogeochemical cycles of nutrients, such as carbon (C), nitrogen (N), and phosphorus (P). Studies in urban areas, however, often include measurements at only a few sites, either in an urban-rural comparison or as an anchor along an urban-rural gradient. In my dissertation work, I deployed a network of sites across the greater Boston area to measure several key biogeochemical processes: 1) rates of carbon dioxide (CO2) efflux through soil respiration, 2) atmospheric inputs and soil solution concentrations of N, P, and organic C, and 3) rates of N mineralization and nitrification in soils. I found that urban soil respiration is driven by landowner management and that respiration from urban residential soils produces almost 75% of the CO2 as fossil fuel emissions in these areas during the growing season. I also found that mean fluxes of inorganic N in throughfall are double rural rates and vary more than threefold throughout the urban area, exhibiting rates at some urban sites which are as low as rural rates. These rates are driven by vehicular N emissions and local fertilizer inputs, and are decoupled from rates of soil biogeochemical cycling of C and N. Finally, I found atmospheric fluxes of organic N equaling almost 40% of total atmospheric N inputs, atmospheric inputs of organic C on par with rural rates, atmospheric inputs of P similar to rates of P in parking lot runoff, and an enhancement of nutrient inputs to urban ecosystems by the urban tree canopy. My dissertation work highlights the need for a more thorough understanding of biogeochemical fluxes in cities, provides further impetus for the development of a more holistic, multifaceted understanding of urbanization, and suggests that urban areas should be studied as systems unto themselves, rather than strictly in comparison to rural areas.en_US
dc.language.isoen_US
dc.subjectBiogeochemistryen_US
dc.subjectAtmospheric depositionen_US
dc.subjectCarbon cycleen_US
dc.subjectNitrogen cycleen_US
dc.subjectPhosphorus cycleen_US
dc.subjectUrban biogeochemistryen_US
dc.subjectUrban ecologyen_US
dc.titleBiogeochemical cycling of carbon, nitrogen, and phosphorus across the greater Boston areaen_US
dc.typeThesis/Dissertationen_US
dc.date.updated2018-08-29T01:06:10Z
etd.degree.nameDoctor of Philosophyen_US
etd.degree.leveldoctoralen_US
etd.degree.disciplineBiologyen_US
etd.degree.grantorBoston Universityen_US


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