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Sonti NF, Groffman PM, Nowak DJ, Henning JG, Avolio ML, Rosi EJ. Urban net primary production: Concepts, field methods, and Baltimore, Maryland, USA case study. ECOLOGICAL APPLICATIONS : A PUBLICATION OF THE ECOLOGICAL SOCIETY OF AMERICA 2022; 32:e2562. [PMID: 35138007 DOI: 10.1002/eap.2562] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/24/2021] [Accepted: 12/01/2021] [Indexed: 06/14/2023]
Abstract
Given the large and increasing amount of urban, suburban, and exurban land use on Earth, there is a need to accurately assess net primary productivity (NPP) of urban ecosystems. However, the heterogeneous and dynamic urban mosaic presents challenges to the measurement of NPP, creating landscapes that may appear more similar to a savanna than to the native landscape replaced. Studies of urban biomass have tended to focus on one type of vegetation (e.g., lawns or trees). Yet a focus on the ecology of the city should include the entire urban ecosystem rather than the separate investigation of its parts. Furthermore, few studies have attempted to measure urban aboveground NPP (ANPP) using field-based methods. Most studies project growth rates from measurements of tree diameter to estimate annual ANPP or use remote sensing approaches. In addition, field-based methods for measuring NPP do not address any special considerations for adapting such field methods to urban landscapes. Frequent planting and partial or complete removal of herbaceous and woody plants can make it difficult to accurately quantify increments and losses of plant biomass throughout an urban landscape. In this study, we review how ANPP of urban landscapes can be estimated based on field measurements, highlighting the challenges specific to urban areas. We then estimated ANPP of woody and herbaceous vegetation over a 15-year period for Baltimore, MD, USA using a combination of plot-based field data and published values from the literature. Baltimore's citywide ANPP was estimated to be 355.8 g m-2 , a result that we then put into context through comparison with other North American Long-Term Ecological Research (LTER) sites and mean annual precipitation. We found our estimate of Baltimore citywide ANPP to be only approximately half as much (or less) than ANPP at forested LTER sites of the eastern United States, and more comparable to grassland, oldfield, desert, or boreal forest ANPP. We also found that Baltimore had low productivity for its level of precipitation. We conclude with a discussion of the significance of accurate assessment of primary productivity of urban ecosystems and critical future research needs.
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Affiliation(s)
- Nancy F Sonti
- USDA Forest Service Northern Research Station, Baltimore, Maryland, USA
| | - Peter M Groffman
- Advanced Science Research Center at the Graduate Center, City University of New York, New York, New York, USA
- Cary Institute of Ecosystem Studies, Millbrook, New York, USA
| | - David J Nowak
- USDA Forest Service Northern Research Station, Syracuse, New York, USA
| | - Jason G Henning
- The Davey Institute and USDA Forest Service, Philadelphia, Pennsylvania, USA
| | - Meghan L Avolio
- Department of Earth and Planetary Sciences, Johns Hopkins University, Baltimore, Maryland, USA
| | - Emma J Rosi
- Cary Institute of Ecosystem Studies, Millbrook, New York, USA
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Zhang Y, Yin P, Li X, Niu Q, Wang Y, Cao W, Huang J, Chen H, Yao X, Yu L, Li B. The divergent response of vegetation phenology to urbanization: A case study of Beijing city, China. THE SCIENCE OF THE TOTAL ENVIRONMENT 2022; 803:150079. [PMID: 34525721 DOI: 10.1016/j.scitotenv.2021.150079] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/11/2021] [Revised: 08/28/2021] [Accepted: 08/29/2021] [Indexed: 06/13/2023]
Abstract
Characterizing the relationship between vegetation phenology and urbanization indicators is essential to understand the impacts of human activities on urban ecosystems. In this study, we explored the response of vegetation phenology to urbanization in Beijing (China) during 2001-2018, using impervious surface area (ISA) and the information of urban-rural gradients (i.e., concentric rings from the urban core to surrounding rural areas) as the urbanization indicators. We found the change rates of vegetation phenology in urban areas are 1.3 and 1.1 days per year for start of season (SOS) and end of season (EOS), respectively, about three times faster than that in forest. Moreover, we found a divergent response of SOS with the increase of ISA, which differs from previous results with advanced SOS in the urban environment than surrounding rural areas. This might be attributed to the mixed land cover types and the thermal environment caused by the urban heat island in the urban environment. Similarly, a divergent pattern of phenological indicators along the urban-rural gradient shows a non-linear response of vegetation phenology to urbanization. These findings provide new insights into the complicated interactions between vegetation phenology and urban environments. High-resolution weather data are required to support process-based vegetation phenology models in the future, particularly under different global urbanization and climate change scenarios.
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Affiliation(s)
- Yehua Zhang
- College of Land Science and Technology, China Agricultural University, Beijing 100083, China
| | - Peiyi Yin
- College of Land Science and Technology, China Agricultural University, Beijing 100083, China
| | - Xuecao Li
- College of Land Science and Technology, China Agricultural University, Beijing 100083, China; Key Laboratory of Remote Sensing for Agri-Hazards, Ministry of Agriculture and Rural Affairs, Beijing 100083, China.
| | - Quandi Niu
- College of Land Science and Technology, China Agricultural University, Beijing 100083, China
| | - Yixuan Wang
- College of Land Science and Technology, China Agricultural University, Beijing 100083, China
| | - Wenting Cao
- State Key Laboratory of Satellite Ocean Environment Dynamics, Second Institute of Oceanography, Ministry of Natural Resources, Hangzhou 310012, China
| | - Jianxi Huang
- College of Land Science and Technology, China Agricultural University, Beijing 100083, China; Key Laboratory of Remote Sensing for Agri-Hazards, Ministry of Agriculture and Rural Affairs, Beijing 100083, China
| | - Han Chen
- Swiss Reinsurance Company Ltd Beijing Branch, Beijing 100022, China
| | - Xiaochuang Yao
- College of Land Science and Technology, China Agricultural University, Beijing 100083, China; Key Laboratory of Remote Sensing for Agri-Hazards, Ministry of Agriculture and Rural Affairs, Beijing 100083, China
| | - Le Yu
- Department of Earth System Science, Tsinghua University, Beijing 100084, China
| | - Baoguo Li
- College of Land Science and Technology, China Agricultural University, Beijing 100083, China
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Angot H, Rutkowski E, Sargent M, Wofsy SC, Hutyra LR, Howard D, Obrist D, Selin NE. Atmospheric mercury sources in a coastal-urban environment: a case study in Boston, Massachusetts, USA. ENVIRONMENTAL SCIENCE. PROCESSES & IMPACTS 2021; 23:1914-1929. [PMID: 34739015 DOI: 10.1039/d1em00253h] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
Mercury (Hg) is an environmental toxicant dangerous to human health and the environment. Its anthropogenic emissions are regulated by global, regional, and local policies. Here, we investigate Hg sources in the coastal city of Boston, the third largest metropolitan area in the Northeastern United States. With a median of 1.37 ng m-3, atmospheric Hg concentrations measured from August 2017 to April 2019 were at the low end of the range reported in the Northern Hemisphere and in the range reported at North American rural sites. Despite relatively low ambient Hg concentrations, we estimate anthropogenic emissions to be 3-7 times higher than in current emission inventories using a measurement-model framework, suggesting an underestimation of small point and/or nonpoint emissions. We also test the hypothesis that a legacy Hg source from the ocean contributes to atmospheric Hg concentrations in the study area; legacy emissions (recycling of previously deposited Hg) account for ∼60% of Hg emitted annually worldwide (and much of this recycling takes place through the oceans). We find that elevated concentrations observed during easterly oceanic winds can be fully explained by low wind speeds and recirculating air allowing for accumulation of land-based emissions. This study suggests that the influence of nonpoint land-based emissions may be comparable in size to point sources in some regions and highlights the benefits of further top-down studies in other areas.
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Affiliation(s)
- Hélène Angot
- Institute for Data, Systems, and Society, Massachusetts Institute of Technology, Cambridge, MA, USA.
- Extreme Environments Research Laboratory, École Polytechnique Fédérale de Lausanne (EPFL) Valais, Wallis, Sion, Switzerland
| | - Emma Rutkowski
- Department of Earth, Atmospheric, and Planetary Sciences, Massachusetts Institute of Technology, Cambridge, MA, USA
| | - Maryann Sargent
- School of Engineering and Applied Science, Harvard University, Cambridge, MA, USA
| | - Steven C Wofsy
- School of Engineering and Applied Science, Harvard University, Cambridge, MA, USA
| | - Lucy R Hutyra
- Department of Earth and Environment, Boston University, Boston, MA, USA
| | - Dean Howard
- Department of Environmental, Earth, and Atmospheric Sciences, University of Massachusetts-Lowell, MA, USA
- Institute of Arctic and Alpine Research, University of Colorado Boulder, Boulder, CO, USA
| | - Daniel Obrist
- Department of Environmental, Earth, and Atmospheric Sciences, University of Massachusetts-Lowell, MA, USA
| | - Noelle E Selin
- Institute for Data, Systems, and Society, Massachusetts Institute of Technology, Cambridge, MA, USA.
- Department of Earth, Atmospheric, and Planetary Sciences, Massachusetts Institute of Technology, Cambridge, MA, USA
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Dust Characterization and Its Potential Impact during the 2014–2015 Fogo Volcano Eruption (Cape Verde). MINERALS 2021. [DOI: 10.3390/min11111275] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
Fogo (Fogo Island) is the youngest and most active volcano of Cape Verde. The last eruption occurred in 2014–2015. Aiming to assess the dust sources that impacted the air quality during the present study period, fresh lava samples were collected, while Saharan dust intrusions and transport were modeled. Rooftop dust was also collected on the island dwellings and a mineralogical and chemical characterization was undertaken. Air quality monitors were used to obtain concentrations of atmospheric particulate matter (PM) and gaseous pollutants. The mineralogical constitution was assessed by XRD and Electron Microprobe. The pseudototal chemical concentration was performed by XRF, ICP-MS and SEM; the latter includes particles morphology. During the study, WRF-CHIMERE results showed the intrusion of desert dust which affected the air quality. Lava was classified as tephritic to basanitic, with high potassium content. The Pollution Load Index for rooftop dust was >1 in all samples, suggesting an enrichment. Higher values were found in dust size fraction <63 µm, with contamination factor pointing to high enrichment of As, Ni and Pb, and very high enrichment of Cd. The non-carcinogenic hazard estimated for children suggested that health problems may arise. The carcinogenic risk was above the target risk, mostly due to As > Pb > Co. Ingestion was the main exposure route. PM10 concentrations exceeded the 24-h mean of 50 µg/m3 recommended by WHO. Nevertheless, TVOCs displayed levels lower than guidelines. The highest levels of CO2 were recorded in more populated villages and farthest from the volcano.
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Lakho FH, Vergote J, Ihsan-Ul-Haq Khan H, Depuydt V, Depreeuw T, Van Hulle SWH, Rousseau DPL. Total value wall: Full scale demonstration of a green wall for grey water treatment and recycling. JOURNAL OF ENVIRONMENTAL MANAGEMENT 2021; 298:113489. [PMID: 34426216 DOI: 10.1016/j.jenvman.2021.113489] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/06/2021] [Revised: 07/13/2021] [Accepted: 08/05/2021] [Indexed: 06/13/2023]
Abstract
Greywater treatment and reuse for non-potable purposes in urban areas has become a widely researched topic to reduce the burden on fresh water resources. This study reports on the use of a green wall for treating grey water and reusing the effluent for toilet flushing, called Total Value Wall (TVW). Initially, the effectiveness of (mixtures of) different substrates, i.e. lava, lightweight expanded clay aggregates, organic soil and biochar was investigated by means of column tests. All substrates were first examined for hydraulic characteristics and later on the columns were fed with synthetic grey wastewater and followed up in terms of removal efficiency of COD and detergents. The mixture consisting of lava (50%), organic soil (25%) and biochar (25%) proved to be optimal both in terms of percolation rates and removal efficiencies, and was thus selected for the full-scale system. The full-scale TVW of 14.4 m2 was installed at a terraced house in Ghent (Belgium), and was loaded with grey water at 100 L per day. Influent and effluent quality were routinely monitored by grab sampling, water savings were monitored by means of flow meters, and electricity consumption was also accounted for. The TVW was further equipped with sensors that measure temperature, Particulate Matter (PM10) and CO2 in the air. The full-scale system obtained effluent concentrations of 13 mg.L-1 TSS, 91 mg.L-1 COD and 5 mg.L-1 BOD5. Ammonium and total coliforms were removed with removal rates of 97% and 99% (2 log units) respectively. However, an increase in effluent concentration of nitrate and phosphate was observed due to leaching from the selected substrate. Available data from the temperature sensors have clearly demonstrated the additional benefit of the TVW as an insulating layer, keeping the heat outside on warmer days, and keeping the heat inside on colder days. Overall, this study demonstrated that the TVW is a sustainable system for greywater treatment and reuse.
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Affiliation(s)
- Fida Hussain Lakho
- Laboratory for Industrial Water and Ecotechnology (LIWET), Department of Green Chemistry and Technology, Ghent University Campus Kortrijk, Sint-Martens Latemlaan 2B, B-8500, Kortrijk, Belgium.
| | - Jarne Vergote
- Laboratory for Industrial Water and Ecotechnology (LIWET), Department of Green Chemistry and Technology, Ghent University Campus Kortrijk, Sint-Martens Latemlaan 2B, B-8500, Kortrijk, Belgium
| | - Hafiz Ihsan-Ul-Haq Khan
- Laboratory for Industrial Water and Ecotechnology (LIWET), Department of Green Chemistry and Technology, Ghent University Campus Kortrijk, Sint-Martens Latemlaan 2B, B-8500, Kortrijk, Belgium
| | - Veerle Depuydt
- Flanders Knowledge Center Water (Vlakwa), Leiestraat 22, B-8500, Kortrijk, Belgium
| | - Teun Depreeuw
- Muurtuin, Vandenpeereboomstraat 16, 2140, Borgerhout, Belgium
| | - Stijn W H Van Hulle
- Laboratory for Industrial Water and Ecotechnology (LIWET), Department of Green Chemistry and Technology, Ghent University Campus Kortrijk, Sint-Martens Latemlaan 2B, B-8500, Kortrijk, Belgium
| | - Diederik P L Rousseau
- Laboratory for Industrial Water and Ecotechnology (LIWET), Department of Green Chemistry and Technology, Ghent University Campus Kortrijk, Sint-Martens Latemlaan 2B, B-8500, Kortrijk, Belgium
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6
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Impacts of strengthened warming by urban heat island on carbon sequestration of urban ecosystems in a subtropical city of China. Urban Ecosyst 2021. [DOI: 10.1007/s11252-021-01104-8] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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7
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Miles NL, Davis KJ, Richardson SJ, Lauvaux T, Martins DK, Deng AJ, Balashov N, Gurney KR, Liang J, Roest G, Wang JA, Turnbull JC. The influence of near-field fluxes on seasonal carbon dioxide enhancements: results from the Indianapolis Flux Experiment (INFLUX). CARBON BALANCE AND MANAGEMENT 2021; 16:4. [PMID: 33515367 PMCID: PMC7847578 DOI: 10.1186/s13021-020-00166-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 08/25/2020] [Accepted: 12/18/2020] [Indexed: 06/12/2023]
Abstract
BACKGROUND Networks of tower-based CO2 mole fraction sensors have been deployed by various groups in and around cities across the world to quantify anthropogenic CO2 emissions from metropolitan areas. A critical aspect in these approaches is the separation of atmospheric signatures from distant sources and sinks (i.e., the background) from local emissions and biogenic fluxes. We examined CO2 enhancements compared to forested and agricultural background towers in Indianapolis, Indiana, USA, as a function of season and compared them to modeled results, as a part of the Indianapolis Flux (INFLUX) project. RESULTS At the INFLUX urban tower sites, daytime growing season enhancement on a monthly timescale was up to 4.3-6.5 ppm, 2.6 times as large as those in the dormant season, on average. The enhancement differed significantly depending on choice of background and time of year, being 2.8 ppm higher in June and 1.8 ppm lower in August using a forested background tower compared to an agricultural background tower. A prediction based on land cover and observed CO2 fluxes showed that differences in phenology and drawdown intensities drove measured differences in enhancements. Forward modelled CO2 enhancements using fossil fuel and biogenic fluxes indicated growing season model-data mismatch of 1.1 ± 1.7 ppm for the agricultural background and 2.1 ± 0.5 ppm for the forested background, corresponding to 25-29% of the modelled CO2 enhancements. The model-data total CO2 mismatch during the dormant season was low, - 0.1 ± 0.5 ppm. CONCLUSIONS Because growing season biogenic fluxes at the background towers are large, the urban enhancements must be disentangled from the biogenic signal, and growing season increases in CO2 enhancement could be misinterpreted as increased anthropogenic fluxes if the background ecosystem CO2 drawdown is not considered. The magnitude and timing of enhancements depend on the land cover type and net fluxes surrounding each background tower, so a simple box model is not appropriate for interpretation of these data. Quantification of the seasonality and magnitude of the biological fluxes in the study region using high-resolution and detailed biogenic models is necessary for the interpretation of tower-based urban CO2 networks for cities with significant vegetation.
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Affiliation(s)
- Natasha L Miles
- Department of Meteorology and Atmospheric Science, The Pennsylvania State University, University Park, PA, 16802, USA.
| | - Kenneth J Davis
- Department of Meteorology and Atmospheric Science, The Pennsylvania State University, University Park, PA, 16802, USA
- Earth and Environmental Systems Institute, The Pennsylvania State University, University Park, PA, 16802, USA
| | - Scott J Richardson
- Department of Meteorology and Atmospheric Science, The Pennsylvania State University, University Park, PA, 16802, USA
| | - Thomas Lauvaux
- Department of Meteorology and Atmospheric Science, The Pennsylvania State University, University Park, PA, 16802, USA
- Laboratoire des Sciences du Climat et de l'Environnement (LSCE), 91190, Saint-Aubin, France
| | - Douglas K Martins
- Department of Meteorology and Atmospheric Science, The Pennsylvania State University, University Park, PA, 16802, USA
- FLIR Systems, Inc, West Lafayette, IN, 47906, USA
| | - A J Deng
- Department of Meteorology and Atmospheric Science, The Pennsylvania State University, University Park, PA, 16802, USA
- Utopus Insights, Inc, Valhalla, NY, 10595, USA
| | - Nikolay Balashov
- Department of Meteorology and Atmospheric Science, The Pennsylvania State University, University Park, PA, 16802, USA
- NASA Goddard Space Flight Center/Universities Space Research Association, Greenbelt, MD, 20771, USA
| | | | - Jianming Liang
- Northern Arizona University, Flagstaff, AZ, 86011, USA
- Environmental Systems Research Institute, Redlands, CA, 92373, USA
| | - Geoff Roest
- Northern Arizona University, Flagstaff, AZ, 86011, USA
| | - Jonathan A Wang
- Boston University, Boston, MA, 02215, USA
- University of California, Irvine, CA, 92697, USA
| | - Jocelyn C Turnbull
- GNS Science, Lower Hutt, 5040, New Zealand
- CIRES, University of Colorado at Boulder, Boulder, CO, USA
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8
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Mallia DV, Mitchell LE, Kunik L, Fasoli B, Bares R, Gurney KR, Mendoza DL, Lin JC. Constraining Urban CO 2 Emissions Using Mobile Observations from a Light Rail Public Transit Platform. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2020; 54:15613-15621. [PMID: 33274635 DOI: 10.1021/acs.est.0c04388] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
Urban environments are characterized by pronounced spatiotemporal heterogeneity, which can present sampling challenges when utilizing conventional greenhouse gas (GHG) measurement systems. In Salt Lake City, Utah, a GHG instrument was deployed on a light rail train car that continuously traverses the Salt Lake Valley (SLV) through a range of urban typologies. CO2 measurements from a light rail train car were used within a Bayesian inverse modeling framework to constrain urban emissions across the SLV during the fall of 2015. The primary objectives of this study were to (1) evaluate whether ground-based mobile measurements could be used to constrain urban emissions using an inverse modeling framework and (2) quantify the information that mobile observations provided relative to conventional GHG monitoring networks. Preliminary results suggest that ingesting mobile measurements into an inverse modeling framework generated a posterior emission estimate that more closely aligned with observations, reduced posterior emission uncertainties, and extends the geographical extent of emission adjustments.
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Affiliation(s)
- Derek V Mallia
- Department of Atmospheric Sciences, University of Utah, Salt Lake City, Utah 84112, United States
| | - Logan E Mitchell
- Department of Atmospheric Sciences, University of Utah, Salt Lake City, Utah 84112, United States
| | - Lewis Kunik
- Department of Atmospheric Sciences, University of Utah, Salt Lake City, Utah 84112, United States
| | - Ben Fasoli
- Department of Atmospheric Sciences, University of Utah, Salt Lake City, Utah 84112, United States
| | - Ryan Bares
- Department of Atmospheric Sciences, University of Utah, Salt Lake City, Utah 84112, United States
| | - Kevin R Gurney
- School of Informatics, Computing and Cyber Systems, Northern Arizona University, Flagstaff, Arizona 86011, United States
| | - Daniel L Mendoza
- Department of Atmospheric Sciences, University of Utah, Salt Lake City, Utah 84112, United States
- Pulmonary Division, University of Utah, Salt Lake City, Utah 84112, United States
- Department of City & Metropolitan Planning, University of Utah, Salt Lake City, Utah 84112, United States
| | - John C Lin
- Department of Atmospheric Sciences, University of Utah, Salt Lake City, Utah 84112, United States
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Urban CO2 Budget: Spatial and Seasonal Variability of CO2 Emissions in Krakow, Poland. ATMOSPHERE 2020. [DOI: 10.3390/atmos11060629] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Krakow, with an area of 327 km2 and over 750,000 inhabitants, is one of the largest cities in Poland. Within the administrative city borders several anthropogenic CO2 source types are located, including car traffic, household coal and natural gas burning, and industrial emissions. Additionally, the biosphere produces its own, seasonally variable, input to the local atmospheric carbon budget. In order to quantify each of CO2 budget contributions to the local atmosphere, a number of analytical and numerical techniques have been implemented. The seasonal variability of CO2 emission from soils around the city has been directly measured using the chamber method; CO2 net flux from an area containing several source types has been measured with a relaxed eddy accumulation—a variation of the eddy covariance method. Global emissions inventory, as well as local statistical data have been utilized to assess anthropogenic component of the budget. As other cities where CO2 budget was quantified, Krakow proved to be a net source of this greenhouse gas, and the calculated annual mean net flux of CO2 to the atmosphere equal 6.1 kg C m−2 is consistent with previous estimations.
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10
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Measuring Multi-Scale Urban Forest Carbon Flux Dynamics Using an Integrated Eddy Covariance Technique. SUSTAINABILITY 2019. [DOI: 10.3390/su11164335] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
The multi-scale carbon-carbon dioxide (C-CO2) dynamics of subtropical urban forests and other green and grey infrastructure types were explored in an urbanized campus near Shanghai, China. We integrated eddy covariance (EC) C-CO2 flux measurements and the Agroscope Reckenholz-Tänikon footprint tool to analyze C-CO2 dynamics at the landscape-scale as well as in local-scale urban forest patches during one year. The approach measured the C-CO2 flux from different contributing areas depending on wind directions and atmospheric stability. Although the study landscape was a net carbon source (2.98 Mg C ha−1 yr−1), we found the mean CO2 flux in urban forest patches was −1.32 μmol m−2s−1, indicating that these patches function as a carbon sink with an annual carbon balance of −5.00 Mg C ha−1. These results indicate that urban forest patches and vegetation (i.e., green infrastructure) composition can be designed to maximize the sequestration of CO2. This novel integrated modeling approach can be used to facilitate the study of the multi-scale effects of urban forests and green infrastructure on CO2 and to establish low-carbon emitting planning and planting designs in the subtropics.
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11
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Gross L, Weber R, Wolf M, Crooks JL. The impact of weather and climate on pollen concentrations in Denver, Colorado, 2010-2018. Ann Allergy Asthma Immunol 2019; 123:494-502.e4. [PMID: 31401104 DOI: 10.1016/j.anai.2019.08.002] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2019] [Revised: 07/24/2019] [Accepted: 08/04/2019] [Indexed: 11/17/2022]
Abstract
BACKGROUND Increasing evidence indicates that climate change is affecting the timing of pollen season and concentrations of allergenic pollens. To date, pollen trends and their associations with meteorological variables have not been studied in most of the United States. OBJECTIVE The purpose of this study was to investigate the effects of weather and climate on pollen concentrations and pollen season timing in Denver, Colorado. METHODS We retrospectively analyzed tree, grass, and weed pollen counts and meteorological variables from 2010-2018 using linear and Poisson regression models. RESULTS Pollen season timing did not demonstrate uniform trends from 2010 to 2018. Certain species demonstrated earlier season start dates (linden, oak) or end dates (birch, maple), and others had later end dates (oak, grass). Only a few species demonstrated changes in season duration (linden, oak, maple, birch) and peak date (maple, birch). Pollen concentrations either remained stable or increased over the years. Temperature and carbon dioxide levels increased over the study period, with the exception of decreased temperature in August. Wind speed remained stable or decreased over the study period. CONCLUSION This study illustrates the complex interactions between pollens and meteorology. Meteorological variables associated with climate change do appear to affect allergenic pollens, though the relationship is variable both amongst pollens and from year to year.
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Affiliation(s)
- Lara Gross
- Dallas Allergy & Asthma Center, Dallas, Texas; National Jewish Health, Denver, Colorado; University of Colorado School of Medicine, Aurora, Colorado
| | - Richard Weber
- National Jewish Health, Denver, Colorado; University of Colorado School of Medicine, Aurora, Colorado
| | - Molly Wolf
- National Jewish Health, Denver, Colorado
| | - James L Crooks
- University of Colorado School of Medicine, Aurora, Colorado; Colorado School of Public Health, Aurora, Colorado.
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12
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Live fast, die young: Accelerated growth, mortality, and turnover in street trees. PLoS One 2019; 14:e0215846. [PMID: 31067257 PMCID: PMC6505744 DOI: 10.1371/journal.pone.0215846] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2018] [Accepted: 04/09/2019] [Indexed: 11/19/2022] Open
Abstract
Municipalities are embracing greening initiatives as a key strategy for improving urban sustainability and combatting the environmental impacts of expansive urbanization. Many greening initiatives include goals to increase urban canopy cover through tree planting, however, our understanding of street tree ecosystem dynamics is limited and our understanding of vegetation structure and function based on intact, rural forests does not apply well to urban ecosystems. In this study, we estimate size-specific growth, mortality, and planting rates in trees under municipal control, use a box model to forecast short-term changes in street tree aboveground carbon pools under several planting and management scenarios, and compare our findings to rural, forested systems. We find accelerated rates of carbon cycling in street trees with mean diameter growth rates nearly four times faster in Boston, MA, USA (0.78 ± 0.02 cm yr-1) than in rural forest stands of MA (0.21 ± 0.02 cm yr-1) and mean mortality rates more than double rural forested rates (3.06 ± 0.25% yr-1 in street trees; 1.41 ± 0.04% yr-1 in rural trees). Despite the enhanced growth of urban trees, high mortality losses result in a net loss of street tree carbon storage over time (-0.15 ± 0.09 Mg C ha-1 yr-1). Planting initiatives alone may not be sufficient to maintain or enhance canopy cover and biomass due to the unique demographics of urban ecosystems. Initiatives to aid in the establishment and preservation of tree health are central for increasing street tree canopy cover and maintaining/increasing carbon storage in vegetation. Strategic combinations of planting and maintenance will maximize the viability of greening initiatives as an effective climate mitigation tool.
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13
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Cai D, Fraedrich K, Guan Y, Guo S, Zhang C, Zhu X. Urbanization and climate change: Insights from eco-hydrological diagnostics. THE SCIENCE OF THE TOTAL ENVIRONMENT 2019; 647:29-36. [PMID: 30077852 DOI: 10.1016/j.scitotenv.2018.07.319] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/24/2017] [Revised: 07/16/2018] [Accepted: 07/23/2018] [Indexed: 06/08/2023]
Abstract
To quantify how urbanization induced long-term changes have altered the evolution of urban climate, a novel eco-hydrological diagnostic is introduced and applied globally, to a developing and a developed country (China and US-America). Urban areas are (i) geographically identified by remote sensing based nighttime light, (ii) physically embedded in state spaces spanned by suitable combinations of surface energy and water fluxes comprising the rainfall-runoff chain, and (iii) dynamically characterized by the time evolution of the surface fluxes at geographically fixed locations, analyzed as trajectories in state space, and interpreted by an attribution model separating anthropogenic from climate induced causes. The results describe the long term climatological settings of urban areas in a net radiation versus dryness diagram, while the attribution of change is diagnosed in a state space spanned by energy and water excess: (i) Cities in China are characterized by a bi-modal distribution separated by the boundary between water and energy-limited (northern and southern) regimes while US-American cities are assembling unimodally on this boundary, and globally the urbanized areas are also aligned along this boundary between water and energy-limited regimes. (ii) Attribution of eco-hydrological changes of urbanized regions to climate and human-induced causes shows also basic differences between the developing and developed country: urbanization in Chinese cities is characterized by a 'wet-gets-drier' and 'dry-gets-wetter' paradigm of the climate-induced contributions, due to which cities tend towards a unimodal state as it is observed for US-American urban areas. Finally, implications for large scale city planning are discussed in the outlook.
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Affiliation(s)
- Danlu Cai
- Institute of Remote Sensing and Digital Earth, Chinese Academy of Sciences, Beijing, China.
| | | | - Yanning Guan
- Institute of Remote Sensing and Digital Earth, Chinese Academy of Sciences, Beijing, China.
| | - Shan Guo
- Institute of Remote Sensing and Digital Earth, Chinese Academy of Sciences, Beijing, China
| | - Chunyan Zhang
- Institute of Remote Sensing and Digital Earth, Chinese Academy of Sciences, Beijing, China
| | - Xiuhua Zhu
- KlimaCampus, Hamburg University, Hamburg, Germany
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14
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Gao Y, Lee X, Liu S, Hu N, Wei X, Hu C, Liu C, Zhang Z, Yang Y. Spatiotemporal variability of the near-surface CO 2 concentration across an industrial-urban-rural transect, Nanjing, China. THE SCIENCE OF THE TOTAL ENVIRONMENT 2018; 631-632:1192-1200. [PMID: 29727944 DOI: 10.1016/j.scitotenv.2018.03.126] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/05/2018] [Revised: 03/09/2018] [Accepted: 03/11/2018] [Indexed: 06/08/2023]
Abstract
Urban lands are CO2 emission hotspots. In this paper, we report the CO2 concentration observations along an industrial-urban-rural transect and in a network of sites in the urban center, in Nanjing, China. The mean CO2 concentration was highest at the industrial site, not at the densely populated urban center (urban: 429.2±8.7ppm, rural: 421.2±10.0ppm, industrial: 443.88±18.3ppm), based on four sampling periods in four different seasons in 2014 and 2015. At the urban sites, a reversed weekend effect was observed, whereby the weekend CO2 concentration was higher than the weekday concentration by a mean of 0.9ppm over the four measurement periods and by 8.1ppm in the spring, suggesting higher traffic volume on weekends than on weekdays. The vertical CO2 gradient was weak above the urban canopy layer, with a mean difference of only 1.1ppm between the 60-m and 110-m measurement heights, reflecting efficient mixing in both daytime and nighttime periods. The average along-wind concentration gradient was 0.25±0.87ppmkm-1 at the height of 110m according to the observations made at five urban sites. Based on a simple box model, we estimated an anthropogenic surface flux of about 0.4mgCO2m-2s-1 for the urban center.
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Affiliation(s)
- Yunqiu Gao
- Yale-NUIST Center on Atmospheric Environment, International Joint Laboratory on Climate and Environment Change (ILCEC), Nanjing University of Information Science & Technology, Nanjing 210044, China; Key Laboratory of Meteorological Disaster, Ministry of Education (KLME), Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters (CIC-FEMD), Nanjing University of Information Science & Technology, Nanjing 210044, China
| | - Xuhui Lee
- Yale-NUIST Center on Atmospheric Environment, International Joint Laboratory on Climate and Environment Change (ILCEC), Nanjing University of Information Science & Technology, Nanjing 210044, China; School of Forestry and Environmental Studies, Yale University, New Haven, CT, USA.
| | - Shoudong Liu
- Yale-NUIST Center on Atmospheric Environment, International Joint Laboratory on Climate and Environment Change (ILCEC), Nanjing University of Information Science & Technology, Nanjing 210044, China; Key Laboratory of Meteorological Disaster, Ministry of Education (KLME), Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters (CIC-FEMD), Nanjing University of Information Science & Technology, Nanjing 210044, China.
| | - Ning Hu
- Yale-NUIST Center on Atmospheric Environment, International Joint Laboratory on Climate and Environment Change (ILCEC), Nanjing University of Information Science & Technology, Nanjing 210044, China; Key Laboratory of Meteorological Disaster, Ministry of Education (KLME), Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters (CIC-FEMD), Nanjing University of Information Science & Technology, Nanjing 210044, China
| | - Xiao Wei
- Yale-NUIST Center on Atmospheric Environment, International Joint Laboratory on Climate and Environment Change (ILCEC), Nanjing University of Information Science & Technology, Nanjing 210044, China; Key Laboratory of Meteorological Disaster, Ministry of Education (KLME), Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters (CIC-FEMD), Nanjing University of Information Science & Technology, Nanjing 210044, China
| | - Cheng Hu
- Yale-NUIST Center on Atmospheric Environment, International Joint Laboratory on Climate and Environment Change (ILCEC), Nanjing University of Information Science & Technology, Nanjing 210044, China; Department of Soil, Water, and Climate, University of Minnesota-Twin Cities, Saint Paul, MN, USA
| | - Cheng Liu
- Yale-NUIST Center on Atmospheric Environment, International Joint Laboratory on Climate and Environment Change (ILCEC), Nanjing University of Information Science & Technology, Nanjing 210044, China; Key Laboratory of Meteorological Disaster, Ministry of Education (KLME), Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters (CIC-FEMD), Nanjing University of Information Science & Technology, Nanjing 210044, China
| | - Zhen Zhang
- Yale-NUIST Center on Atmospheric Environment, International Joint Laboratory on Climate and Environment Change (ILCEC), Nanjing University of Information Science & Technology, Nanjing 210044, China; Key Laboratory of Meteorological Disaster, Ministry of Education (KLME), Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters (CIC-FEMD), Nanjing University of Information Science & Technology, Nanjing 210044, China
| | - Yichen Yang
- Yale-NUIST Center on Atmospheric Environment, International Joint Laboratory on Climate and Environment Change (ILCEC), Nanjing University of Information Science & Technology, Nanjing 210044, China; Key Laboratory of Meteorological Disaster, Ministry of Education (KLME), Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters (CIC-FEMD), Nanjing University of Information Science & Technology, Nanjing 210044, China
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15
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Lahr EC, Dunn RR, Frank SD. Getting ahead of the curve: cities as surrogates for global change. Proc Biol Sci 2018; 285:20180643. [PMID: 30051830 PMCID: PMC6053926 DOI: 10.1098/rspb.2018.0643] [Citation(s) in RCA: 38] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2018] [Accepted: 06/14/2018] [Indexed: 12/20/2022] Open
Abstract
Urbanization represents an unintentional global experiment that can provide insights into how species will respond and interact under future global change scenarios. Cities produce many conditions that are predicted to occur widely in the future, such as warmer temperatures, higher carbon dioxide (CO2) concentrations and exacerbated droughts. In using cities as surrogates for global change, it is challenging to disentangle climate variables-such as temperature-from co-occurring or confounding urban variables-such as impervious surface-and then to understand the interactive effects of multiple climate variables on both individual species and species interactions. However, such interactions are also difficult to replicate experimentally, and thus the challenges of cities are also their unique advantage. Here, we review insights gained from cities, with a focus on plants and arthropods, and how urban findings agree or disagree with experimental predictions and historical data. We discuss the types of hypotheses that can be best tested in cities, caveats to urban research and how to further validate cities as surrogates for global change. Lastly, we summarize how to achieve the goal of using urban species responses to predict broader regional- and ecosystem-level patterns in the future.
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Affiliation(s)
- Eleanor C Lahr
- Department of Applied Ecology, North Carolina State University, Raleigh, NC, USA
- Department of Entomology and Plant Pathology, North Carolina State University, Raleigh, NC, USA
| | - Robert R Dunn
- Department of Applied Ecology, North Carolina State University, Raleigh, NC, USA
| | - Steven D Frank
- Department of Entomology and Plant Pathology, North Carolina State University, Raleigh, NC, USA
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16
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Hardiman BS, Wang JA, Hutyra LR, Gately CK, Getson JM, Friedl MA. Accounting for urban biogenic fluxes in regional carbon budgets. THE SCIENCE OF THE TOTAL ENVIRONMENT 2017; 592:366-372. [PMID: 28324854 DOI: 10.1016/j.scitotenv.2017.03.028] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/18/2017] [Revised: 03/02/2017] [Accepted: 03/03/2017] [Indexed: 06/06/2023]
Abstract
Many ecosystem models incorrectly treat urban areas as devoid of vegetation and biogenic carbon (C) fluxes. We sought to improve estimates of urban biomass and biogenic C fluxes using existing, nationally available data products. We characterized biogenic influence on urban C cycling throughout Massachusetts, USA using an ecosystem model that integrates improved representation of urban vegetation, growing conditions associated with urban heat island (UHI), and altered urban phenology. Boston's biomass density is 1/4 that of rural forests, however 87% of Massachusetts' urban landscape is vegetated. Model results suggest that, kilogram-for-kilogram, urban vegetation cycles C twice as fast as rural forests. Urban vegetation releases (RE) and absorbs (GEE) the equivalent of 11 and 14%, respectively, of anthropogenic emissions in the most urban portions of the state. While urban vegetation in Massachusetts fully sequesters anthropogenic emissions from smaller cities in the region, Boston's UHI reduces annual C storage by >20% such that vegetation offsets only 2% of anthropogenic emissions. Asynchrony between temporal patterns of biogenic and anthropogenic C fluxes further constrains the emissions mitigation potential of urban vegetation. However, neglecting to account for biogenic C fluxes in cities can impair efforts to accurately monitor, report, verify, and reduce anthropogenic emissions.
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Affiliation(s)
- Brady S Hardiman
- Department of Forestry & Natural Resources, Division of Environmental & Ecological Engineering, Purdue University, 715 W State St, West Lafayette, IN 47907, USA; Department of Earth and Environment, Boston University, 685 Commonwealth Avenue, Boston, MA 02215, USA.
| | - Jonathan A Wang
- Department of Earth and Environment, Boston University, 685 Commonwealth Avenue, Boston, MA 02215, USA
| | - Lucy R Hutyra
- Department of Earth and Environment, Boston University, 685 Commonwealth Avenue, Boston, MA 02215, USA
| | - Conor K Gately
- Department of Earth and Environment, Boston University, 685 Commonwealth Avenue, Boston, MA 02215, USA
| | - Jackie M Getson
- Department of Earth and Environment, Boston University, 685 Commonwealth Avenue, Boston, MA 02215, USA
| | - Mark A Friedl
- Department of Earth and Environment, Boston University, 685 Commonwealth Avenue, Boston, MA 02215, USA
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17
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Martin CR, Zeng N, Karion A, Dickerson RR, Ren X, Turpie BN, Weber KJ. Evaluation and environmental correction of ambient CO 2 measurements from a low-cost NDIR sensor. ATMOSPHERIC MEASUREMENT TECHNIQUES 2017; 10:10.5194/amt-10-2383-2017. [PMID: 30996750 PMCID: PMC6463532 DOI: 10.5194/amt-10-2383-2017] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/04/2023]
Abstract
Non-dispersive infrared (NDIR) sensors are a low-cost way to observe carbon dioxide concentrations in air, but their specified accuracy and precision are not sufficient for some scientific applications. An initial evaluation of six SenseAir K30 carbon dioxide NDIR sensors in a lab setting showed that without any calibration or correction, the sensors have an individual root mean square error (RMSE) between ~5 and 21 parts per million (ppm) compared to a research-grade greenhouse gas analyzer using cavity enhanced laser absorption spectroscopy. Through further evaluation, after correcting for environmental variables with coefficients determined through a multivariate linear regression analysis, the calculated difference between the each of six individual K30 NDIR sensors and the higher-precision instrument had an RMSE of between 1.7 and 4.3 ppm for 1 min data. The median RMSE improved from 9.6 for off-the-shelf sensors to 1.9 ppm after correction and calibration, demonstrating the potential to provide useful information for ambient air monitoring.
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Affiliation(s)
- Cory R. Martin
- Department of Atmospheric and Oceanic Science, University of Maryland, College Park, MD 20742, USA
| | - Ning Zeng
- Department of Atmospheric and Oceanic Science, University of Maryland, College Park, MD 20742, USA
- Earth System Science Interdisciplinary Center, University of Maryland, College Park, MD 20742, USA
| | - Anna Karion
- National Institute of Standards and Technology, Gaithersburg, MD 20899, USA
| | - Russell R. Dickerson
- Department of Atmospheric and Oceanic Science, University of Maryland, College Park, MD 20742, USA
- Earth System Science Interdisciplinary Center, University of Maryland, College Park, MD 20742, USA
| | - Xinrong Ren
- Department of Atmospheric and Oceanic Science, University of Maryland, College Park, MD 20742, USA
- Air Resources Laboratory, National Oceanic and Atmospheric Administration, College Park, MD 20740, USA
| | - Bari N. Turpie
- Department of Atmospheric and Oceanic Science, University of Maryland, College Park, MD 20742, USA
| | - Kristy J. Weber
- Department of Atmospheric and Oceanic Science, University of Maryland, College Park, MD 20742, USA
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18
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Soil surface temperatures reveal moderation of the urban heat island effect by trees and shrubs. Sci Rep 2016; 6:33708. [PMID: 27641002 PMCID: PMC5027384 DOI: 10.1038/srep33708] [Citation(s) in RCA: 70] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2016] [Accepted: 09/01/2016] [Indexed: 11/08/2022] Open
Abstract
Urban areas are major contributors to air pollution and climate change, causing impacts on human health that are amplified by the microclimatological effects of buildings and grey infrastructure through the urban heat island (UHI) effect. Urban greenspaces may be important in reducing surface temperature extremes, but their effects have not been investigated at a city-wide scale. Across a mid-sized UK city we buried temperature loggers at the surface of greenspace soils at 100 sites, stratified by proximity to city centre, vegetation cover and land-use. Mean daily soil surface temperature over 11 months increased by 0.6 °C over the 5 km from the city outskirts to the centre. Trees and shrubs in non-domestic greenspace reduced mean maximum daily soil surface temperatures in the summer by 5.7 °C compared to herbaceous vegetation, but tended to maintain slightly higher temperatures in winter. Trees in domestic gardens, which tend to be smaller, were less effective at reducing summer soil surface temperatures. Our findings reveal that the UHI effects soil temperatures at a city-wide scale, and that in their moderating urban soil surface temperature extremes, trees and shrubs may help to reduce the adverse impacts of urbanization on microclimate, soil processes and human health.
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19
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Decina SM, Hutyra LR, Gately CK, Getson JM, Reinmann AB, Short Gianotti AG, Templer PH. Soil respiration contributes substantially to urban carbon fluxes in the greater Boston area. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2016; 212:433-439. [PMID: 26914093 DOI: 10.1016/j.envpol.2016.01.012] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/21/2015] [Revised: 01/05/2016] [Accepted: 01/05/2016] [Indexed: 06/05/2023]
Abstract
Urban areas are the dominant source of U.S. fossil fuel carbon dioxide (FFCO2) emissions. In the absence of binding international treaties or decisive U.S. federal policy for greenhouse gas regulation, cities have also become leaders in greenhouse gas reduction efforts through climate action plans. These plans focus on anthropogenic carbon flows only, however, ignoring a potentially substantial contribution to atmospheric carbon dioxide (CO2) concentrations from biological respiration. Our aim was to measure the contribution of CO2 efflux from soil respiration to atmospheric CO2 fluxes using an automated CO2 efflux system and to use these measurements to model urban soil CO2 efflux across an urban area. We find that growing season soil respiration is dramatically enhanced in urban areas and represents levels of CO2 efflux of up to 72% of FFCO2 within greater Boston's residential areas, and that soils in urban forests, lawns, and landscaped cover types emit 2.62 ± 0.15, 4.49 ± 0.14, and 6.73 ± 0.26 μmolCO2 m(-2) s(-1), respectively, during the growing season. These rates represent up to 2.2 times greater soil respiration than rates found in nearby rural ecosystems in central Massachusetts (MA), a potential consequence of imported carbon amendments, such as mulch, within a general regime of landowner management. As the scientific community moves rapidly towards monitoring, reporting, and verification of CO2 emissions using ground based approaches and remotely-sensed observations to measure CO2 concentrations, our results show that measurement and modeling of biogenic urban CO2 fluxes will be a critical component for verification of urban climate action plans.
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Affiliation(s)
- Stephen M Decina
- Department of Biology, Boston University, Boston, MA, 02215, USA.
| | - Lucy R Hutyra
- Department of Earth and Environment, Boston University, Boston, MA, 02215, USA.
| | - Conor K Gately
- Department of Earth and Environment, Boston University, Boston, MA, 02215, USA.
| | - Jackie M Getson
- Department of Earth and Environment, Boston University, Boston, MA, 02215, USA.
| | - Andrew B Reinmann
- Department of Earth and Environment, Boston University, Boston, MA, 02215, USA.
| | | | - Pamela H Templer
- Department of Biology, Boston University, Boston, MA, 02215, USA.
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20
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Tree Productivity Enhanced with Conversion from Forest to Urban Land Covers. PLoS One 2015; 10:e0136237. [PMID: 26302444 PMCID: PMC4547753 DOI: 10.1371/journal.pone.0136237] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2015] [Accepted: 07/30/2015] [Indexed: 11/27/2022] Open
Abstract
Urban areas are expanding, changing the structure and productivity of landscapes. While some urban areas have been shown to hold substantial biomass, the productivity of these systems is largely unknown. We assessed how conversion from forest to urban land uses affected both biomass structure and productivity across eastern Massachusetts. We found that urban land uses held less than half the biomass of adjacent forest expanses with a plot level mean biomass density of 33.5 ± 8.0 Mg C ha-1. As the intensity of urban development increased, the canopy cover, stem density, and biomass decreased. Analysis of Quercus rubra tree cores showed that tree-level basal area increment nearly doubled following development, increasing from 17.1 ± 3.0 to 35.8 ± 4.7 cm2 yr-1. Scaling the observed stem densities and growth rates within developed areas suggests an aboveground biomass growth rate of 1.8 ± 0.4 Mg C ha-1 yr-1, a growth rate comparable to nearby, intact forests. The contrasting high growth rates and lower biomass pools within urban areas suggest a highly dynamic ecosystem with rapid turnover. As global urban extent continues to grow, cities consider climate mitigation options, and as the verification of net greenhouse gas emissions emerges as critical for policy, quantifying the role of urban vegetation in regional-to-global carbon budgets will become ever more important.
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21
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Ng BJL, Hutyra LR, Nguyen H, Cobb AR, Kai FM, Harvey C, Gandois L. Carbon fluxes from an urban tropical grassland. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2015; 203:227-234. [PMID: 24998996 DOI: 10.1016/j.envpol.2014.06.009] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/02/2014] [Revised: 05/29/2014] [Accepted: 06/03/2014] [Indexed: 06/03/2023]
Abstract
Turfgrass covers a large fraction of the urbanized landscape, but the carbon exchange of urban lawns is poorly understood. We used eddy covariance and flux chambers in a grassland field manipulative experiment to quantify the carbon mass balance in a Singapore tropical turfgrass. We also assessed how management and variations in environmental factors influenced CO2 respiration. Standing aboveground turfgrass biomass was 80 gC m(-2), with a mean ecosystem respiration of 7.9 ± 1.1 μmol m(-2) s(-1). The contribution of autotrophic respiration was 49-76% of total ecosystem respiration. Both chamber and eddy covariance measurements suggest the system was in approximate carbon balance. While we did not observe a significant relationship between the respiration rates and soil temperature or moisture, daytime fluxes increased during the rainy interval, indicating strong overall moisture sensitivity. Turfgrass biomass is small, but given its abundance across the urban landscape, it significantly influences diurnal CO2 concentrations.
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Affiliation(s)
- B J L Ng
- Department of Geography, National University of Singapore, Singapore
| | - L R Hutyra
- Boston University, Department of Earth and Environment, Boston, MA, USA.
| | - H Nguyen
- Boston University, Department of Earth and Environment, Boston, MA, USA
| | - A R Cobb
- Singapore-MIT Alliance for Research and Technology, Center for Environmental Sensing and Modeling, 1 CREATE Way, Singapore
| | - F M Kai
- Singapore-MIT Alliance for Research and Technology, Center for Environmental Sensing and Modeling, 1 CREATE Way, Singapore
| | - C Harvey
- Singapore-MIT Alliance for Research and Technology, Center for Environmental Sensing and Modeling, 1 CREATE Way, Singapore; Massachusetts Institute of Technology, Department of Civil and Environmental Engineering, Cambridge, MA, USA
| | - L Gandois
- Singapore-MIT Alliance for Research and Technology, Center for Environmental Sensing and Modeling, 1 CREATE Way, Singapore; Université de Toulouse: UPS, INP, EcoLab (Laboratoire Ecologie fonctionnelle et Environnement), ENSAT, Avenue de l'Agrobiopôle, F-31326 Castanet-Tolosan, France; CNRS, EcoLab, F-31326 Castanet-Tolosan, France
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22
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Ward HC, Kotthaus S, Grimmond CSB, Bjorkegren A, Wilkinson M, Morrison WTJ, Evans JG, Morison JIL, Iamarino M. Effects of urban density on carbon dioxide exchanges: Observations of dense urban, suburban and woodland areas of southern England. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2015; 198:186-200. [PMID: 25613466 DOI: 10.1016/j.envpol.2014.12.031] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/27/2014] [Revised: 10/12/2014] [Accepted: 12/26/2014] [Indexed: 05/22/2023]
Abstract
Anthropogenic and biogenic controls on the surface-atmosphere exchange of CO2 are explored for three different environments. Similarities are seen between suburban and woodland sites during summer, when photosynthesis and respiration determine the diurnal pattern of the CO2 flux. In winter, emissions from human activities dominate urban and suburban fluxes; building emissions increase during cold weather, while traffic is a major component of CO2 emissions all year round. Observed CO2 fluxes reflect diurnal traffic patterns (busy throughout the day (urban); rush-hour peaks (suburban)) and vary between working days and non-working days, except at the woodland site. Suburban vegetation offsets some anthropogenic emissions, but 24-h CO2 fluxes are usually positive even during summer. Observations are compared to estimated emissions from simple models and inventories. Annual CO2 exchanges are significantly different between sites, demonstrating the impacts of increasing urban density (and decreasing vegetation fraction) on the CO2 flux to the atmosphere.
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Affiliation(s)
- H C Ward
- Department of Meteorology, University of Reading, Reading, RG6 6BB, UK; Centre for Ecology and Hydrology, Wallingford, Oxfordshire, OX10 8BB, UK.
| | - S Kotthaus
- Department of Meteorology, University of Reading, Reading, RG6 6BB, UK; Department of Geography, King's College London, London, WC2R 2LS, UK
| | - C S B Grimmond
- Department of Meteorology, University of Reading, Reading, RG6 6BB, UK
| | - A Bjorkegren
- Department of Geography, King's College London, London, WC2R 2LS, UK
| | - M Wilkinson
- Forest Research, Centre for Forestry and Climate Change, Alice Holt Lodge, Farnham, Surrey, GU10 4LH, UK
| | - W T J Morrison
- Department of Meteorology, University of Reading, Reading, RG6 6BB, UK
| | - J G Evans
- Centre for Ecology and Hydrology, Wallingford, Oxfordshire, OX10 8BB, UK
| | - J I L Morison
- Forest Research, Centre for Forestry and Climate Change, Alice Holt Lodge, Farnham, Surrey, GU10 4LH, UK
| | - M Iamarino
- Scuola di Ingegneria, Università degli Studi della Basilicata, 85100, Potenza, Italy
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23
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Youngsteadt E, Dale AG, Terando AJ, Dunn RR, Frank SD. Do cities simulate climate change? A comparison of herbivore response to urban and global warming. GLOBAL CHANGE BIOLOGY 2015; 21:97-105. [PMID: 25163424 DOI: 10.1111/gcb.12692] [Citation(s) in RCA: 55] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/24/2014] [Accepted: 07/08/2014] [Indexed: 06/03/2023]
Abstract
Cities experience elevated temperature, CO2 , and nitrogen deposition decades ahead of the global average, such that biological response to urbanization may predict response to future climate change. This hypothesis remains untested due to a lack of complementary urban and long-term observations. Here, we examine the response of an herbivore, the scale insect Melanaspis tenebricosa, to temperature in the context of an urban heat island, a series of historical temperature fluctuations, and recent climate warming. We survey M. tenebricosa on 55 urban street trees in Raleigh, NC, 342 herbarium specimens collected in the rural southeastern United States from 1895 to 2011, and at 20 rural forest sites represented by both modern (2013) and historical samples. We relate scale insect abundance to August temperatures and find that M. tenebricosa is most common in the hottest parts of the city, on historical specimens collected during warm time periods, and in present-day rural forests compared to the same sites when they were cooler. Scale insects reached their highest densities in the city, but abundance peaked at similar temperatures in urban and historical datasets and tracked temperature on a decadal scale. Although urban habitats are highly modified, species response to a key abiotic factor, temperature, was consistent across urban and rural-forest ecosystems. Cities may be an appropriate but underused system for developing and testing hypotheses about biological effects of climate change. Future work should test the applicability of this model to other groups of organisms.
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Affiliation(s)
- Elsa Youngsteadt
- Department of Entomology, North Carolina State University, Raleigh, NC, 27695-7613, USA
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24
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Raciti SM, Hutyra LR, Newell JD. Mapping carbon storage in urban trees with multi-source remote sensing data: relationships between biomass, land use, and demographics in Boston neighborhoods. THE SCIENCE OF THE TOTAL ENVIRONMENT 2014; 500-501:72-83. [PMID: 25217746 DOI: 10.1016/j.scitotenv.2014.08.070] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/30/2014] [Revised: 08/01/2014] [Accepted: 08/08/2014] [Indexed: 06/03/2023]
Abstract
High resolution maps of urban vegetation and biomass are powerful tools for policy-makers and community groups seeking to reduce rates of urban runoff, moderate urban heat island effects, and mitigate the effects of greenhouse gas emissions. We developed a very high resolution map of urban tree biomass, assessed the scale sensitivities in biomass estimation, compared our results with lower resolution estimates, and explored the demographic relationships in biomass distribution across the City of Boston. We integrated remote sensing data (including LiDAR-based tree height estimates) and field-based observations to map canopy cover and aboveground tree carbon storage at ~1m spatial scale. Mean tree canopy cover was estimated to be 25.5±1.5% and carbon storage was 355Gg (28.8MgCha(-1)) for the City of Boston. Tree biomass was highest in forest patches (110.7MgCha(-1)), but residential (32.8MgCha(-1)) and developed open (23.5MgCha(-1)) land uses also contained relatively high carbon stocks. In contrast with previous studies, we did not find significant correlations between tree biomass and the demographic characteristics of Boston neighborhoods, including income, education, race, or population density. The proportion of households that rent was negatively correlated with urban tree biomass (R(2)=0.26, p=0.04) and correlated with Priority Planting Index values (R(2)=0.55, p=0.001), potentially reflecting differences in land management among rented and owner-occupied residential properties. We compared our very high resolution biomass map to lower resolution biomass products from other sources and found that those products consistently underestimated biomass within urban areas. This underestimation became more severe as spatial resolution decreased. This research demonstrates that 1) urban areas contain considerable tree carbon stocks; 2) canopy cover and biomass may not be related to the demographic characteristics of Boston neighborhoods; and 3) that recent advances in high resolution remote sensing have the potential to improve the characterization and management of urban vegetation.
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Affiliation(s)
- Steve M Raciti
- Department of Biology, Hofstra University, Gittleson Hall, Hempstead, NY 11549, United States; Department of Earth and Environment, Boston University, 685 Commonwealth Ave., Boston, MA 02215, United States.
| | - Lucy R Hutyra
- Department of Earth and Environment, Boston University, 685 Commonwealth Ave., Boston, MA 02215, United States
| | - Jared D Newell
- Department of Earth and Environment, Boston University, 685 Commonwealth Ave., Boston, MA 02215, United States
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