Carbon Cycle of Urban Ecosystems

Urbanization is one of the most irreversible and visible anthropogenic forces on Earth. The fraction of urban population is growing and is predicted to reach 70% of the world’s population by 2050. Urban areas are both drivers and recipients of global environmental change. Carbon cycle of urban areas plays an important role in the feedbacks between urban development and global environmental change. On one side it is a driver of the global environmental change, because more than 70% of global CO2 emissions originate in urban areas. On the other side the global and regional environmental changes such as heat waves, water scarcity, and air pollution influence urban carbon cycle. Carbon cycling through natural (e.g., urban vegetation and soils) and anthropogenic components (e.g., buildings, furniture, landfills, etc.) is intrinsically coupled in urban areas. In cities not only green plants take up carbon, but also concrete buildings. Emissions of carbon from vegetation and soils are complemented by emissions from fossil fuel burning. Urban areas have a large variety of pools to store carbon: from vegetation and soil to buildings, furniture, and landfills. The natural and anthropogenic carbon fluxes through urban areas are controlled by common drivers such as climate and urban form. Three issues are identified as the most important ones for understanding and quantification of urban carbon cycle. They include: (i) the lateral flows of carbon between an urban area and its footprint; (ii) responses of urban vegetation to urban climate and pollution, and (iii) interactions between natural and anthropogenic components of the urban carbon cycle. Because both natural and anthropogenic components are equally important for understanding urban C cycle, they have to be considered simultaneously in the design of any observation strategy or numerical model development. Understanding of the urban C cycle and the whole spectrum of its C pools and fluxes would be beneficial not only for scientists, but also for city governments. It can be instrumental in choosing the optimal policy to reduce urban C footprint.

[1]  Morton A. Barlaz,et al.  Carbon storage during biodegradation of municipal solid waste components in laboratory‐scale landfills , 1998 .

[2]  Elena Mauri,et al.  Satellite monitoring of summer heat waves in the Paris metropolitan area , 2011 .

[3]  T. Peterson,et al.  An integrated approach to improving fossil fuel emissions scenarios with urban ecosystem studies , 2009 .

[4]  Edward B. Rastetter,et al.  Forest Ecosystems, Analysis at Multiple Scales, 2nd Edition , 1999 .

[5]  Jeffrey Kenworthy,et al.  Sustainability and Cities: Overcoming Automobile Dependence , 1999 .

[6]  Richard H. Waring,et al.  Forest Ecosystems: Analysis at Multiple Scales , 1985 .

[7]  T. Derting,et al.  Ecology: A Bridge between Science and Society , 1998 .

[8]  Aumnad Phdungsilp,et al.  Greenhouse gas emissions from global cities. , 2009, Environmental science & technology.

[9]  P. Kasibhatla,et al.  Growth of Continental-Scale Metro-Agro-Plexes, Regional Ozone Pollution, and World Food Production , 1994, Science.

[10]  Toby N. Carlson,et al.  The impact of land use — land cover changes due to urbanization on surface microclimate and hydrology: a satellite perspective , 2000 .

[11]  D. Nowak,et al.  Carbon storage by urban soils in the United States. , 2006, Journal of environmental quality.

[12]  L. Ziska,et al.  Characterization of an urban-rural CO2/temperature gradient and associated changes in initial plant productivity during secondary succession , 2004, Oecologia.

[13]  R. Bornstein,et al.  Urban heat islands and summertime convective thunderstorms in Atlanta: three case studies , 2000 .

[14]  J. Monteith,et al.  Boundary Layer Climates. , 1979 .

[15]  Emergency Response,et al.  Characterization of building-related construction and demolition debris in the United States , 1998 .

[16]  C. Osmond,et al.  Physiological Plant Ecology I , 1981, Encyclopedia of Plant Physiology.

[17]  Kathleen M. Bergen,et al.  Increasing Gross Primary Production (GPP) in the Urbanizing Landscapes of Southeastern Michigan , 2007 .

[18]  J. M. Shepherd,et al.  A Review of Current Investigations of Urban-Induced Rainfall and Recommendations for the Future , 2005 .

[19]  W. Larcher.  Physiological Plant Ecology , 1977 .

[20]  J. Randerson,et al.  Regional patterns of radiocarbon and fossil fuel‐derived CO2 in surface air across North America , 2007 .

[21]  D. Theobald.  Landscape Patterns of Exurban Growth in the USA from 1980 to 2020 , 2005 .

[22]  Lewis H. Ziska,et al.  Elevated atmospheric CO2 concentration and temperature across an urban–rural transect , 2007 .

[23]  D. Nowak,et al.  Carbon storage and sequestration by urban trees in the USA. , 2002, Environmental pollution.

[24]  M. Claussen,et al.  Urbanization impacts on the climate in Europe: Numerical experiments by the PSU-NCAR Mesoscale Model (MM5) , 2008 .

[25]  E. Mcpherson,et al.  Urban ecosystems and the North American carbon cycle , 2006 .

[26]  L. Hutyra,et al.  Terrestrial carbon stocks across a gradient of urbanization: a study of the Seattle, WA region , 2011 .

[27]  Mark Lawrence,et al.  Regional pollution potentials of megacities and other major population centers , 2006 .

[28]  G. Keoleian,et al.  Carbon Stored in Human Settlements: the Conterminous US , 2008 .

[29]  Gregory A. Keoleian,et al.  Carbon stored in human settlements: the conterminous United States , 2010 .

[30]  Galina Churkina,et al.  Modeling the carbon cycle of urban systems , 2008 .

[31]  K. Seto,et al.  Climate Response to Rapid Urban Growth: Evidence of a Human-Induced Precipitation Deficit , 2007 .

[32]  Noah S. Diffenbaugh,et al.  Influence of modern land cover on the climate of the United States , 2009 .

[33]  P. Reich,et al.  Relationships of leaf dark respiration to leaf nitrogen, specific leaf area and leaf life-span: a test across biomes and functional groups , 1998, Oecologia.

[34]  D. Imre,et al.  Ozone production rate and hydrocarbon reactivity in 5 urban areas: A cause of high ozone concentration in Houston , 2002 .

[35]  F. Chapin,et al.  Principles of Terrestrial Ecosystem Ecology , 2002, Springer New York.

[36]  G. Churkina,et al.  The response of the terrestrial biosphere to urbanization: land cover conversion, climate, and urban pollution , 2008 .

[37]  Sigurdur R. Gislason,et al.  Mineral Carbonation of CO2 , 2008 .

[38]  T. Dawson,et al.  Urbanization effects on tree growth in the vicinity of New York City , 2003, Nature.

[39]  D. Pataki,et al.  Spatial patterns of plant isotope tracers in the Los Angeles urban region , 2009, Landscape Ecology.

[40]  Loretta Gratani,et al.  Daily and seasonal variation of CO2 in the city of Rome in relationship with the traffic volume , 2005 .

[41]  David J. Nowak,et al.  People and Trees: Assessing the US Urban Forest Resource , 2001 .

[42]  E. Kalnay,et al.  Impact of urbanization and land-use change on climate , 2003, Nature.

[43]  F. Southworth,et al.  Shrinking the Carbon Footprint of Metropolitan America , 2008 .

[44]  N. Grimm,et al.  Global Change and the Ecology of Cities , 2008, Science.

[45]  A. Townsend‐Small,et al.  Carbon sequestration and greenhouse gas emissions in urban turf , 2010 .

[46]  C. O'Dowd,et al.  Flood or Drought: How Do Aerosols Affect Precipitation? , 2008, Science.

[47]  A. Ramaswami,et al.  A demand-centered, hybrid life-cycle methodology for city-scale greenhouse gas inventories. , 2008, Environmental science & technology.

[48]  Eric J. Barron,et al.  Impacts of agriculture and urbanization on the climate of the Northeastern United States , 2005 .