Quantification of urban forest and grassland carbon fluxes using field measurements and a satellite‐based model in Washington DC/Baltimore area

UrbanCrowns is a software program developed by the USDA Forest Service that computes crown attributes using a side-view digital photograph and a few basic field measurements. From an operational standpoint, it is not known how well the software performs under varying photographic conditions for trees of diverse size, which could impact measurement reproducibility and therefore software utility. Researchers evaluated the robustness of crown dimension computations made with UrbanCrowns for open-grown sugar maples (Acer saccharum) across a range of sizes from recently transplanted to full maturity. It was found that computations of both crown volume and density were highly repeatable across varying photographic distances. For the majority of tree size classes, crown volume and density varied less than 5% on average over distances ranging from 1.5× to 3.0× tree height; however, crown volume errors of 5%–10% were common for larger trees (>46 cm trunk diameter). UrbanCrowns calculations of crown volume showed strong agreement with calculations derived from equations for geometric solids, both in terms of precision (R2 = 0.9783) and accuracy (B1 = 1.0033). These findings suggest that UrbanCrowns has potential as an objective, reliable method for measuring tree crown attributes that are commonly assessed during urban forest inventories.

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Soil Carbon Dioxide Emission in Extreme Environment of the Center of Moscow Megapolis

10.5194/egusphere-egu2020-13890 ◽

2020 ◽

Author(s):

Andrey Dolgikh ◽

Dmitriy Petrov ◽

Inna Brianskaia ◽

Soryia Demina ◽

Ksenia Mahinya ◽

...

Keyword(s):

Carbon Dioxide ◽

Soil Carbon ◽

Carbon Dioxide Emissions ◽

Urban Forest ◽

Carbon Dioxide Emission ◽

Field Measurements ◽

Soil Carbon Dioxide ◽

Historic Center ◽

C Cycle ◽

Soil Emission

Moscow is the largest megapolis in Europe. The area of sealed areas in the center of Moscow is more than 50% (without hydrological objects). Anti-icing mixtures, car traffic, aerosols, dust, trampling - all this leads to the maximum stress of ecosystems in an urban environment Soil emission is the largest component of Gross Respiration in terrestrial ecosystems, including cities. Field measurements of emission allow estimating and comparing the state of both the underground tier and the entire ecosystem in different functional zones of a city with different types of vegetation. Soil emission is the easiest to measure, as compared to other fluxes of &#1057;-exchange. In 2019, field measurements of carbon dioxide emissions were carried out at 15 key sites (15 times, 1 per 2 weeks), which showed that in the historic center, not only the temperature at different depths of the soil, soil moisture, carbon content, particle size distribution, but also the diversity of factors combined into a group of "land use", namely: human tillage, irrigation, lawn mowing, garbage removal, sprinkling peat-compost mixture, trampling, bringing anti-icing reagents, etc., have a contrasting effect on carbon dioxide emissions from urban soils. In some cases, the emission is below the conditional background values (urban forest), in other cases, it is higher up to several times, which allows a new assessment of soils of unsealed (open) areas of the center of a megapolis as an important component of the (micro-) regional C-cycle. The data obtained allow comparing the current state of the upper part of the underground tier of urban ecosystems under the maximum anthropogenic load in the territory of a modern large city, where the share of open surfaces is minimal. The territories, where the ground layer is represented by cultivated lawn, are characterized by the maximum values of soil carbon dioxide emission.The study was supported by the Russian Research Foundation #19-77-30012 (field measurements in the periphery of Moscow) and the Russian Foundation for Basic Research #18-35-20052 (field measurements in the historic center of Moscow).

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Framework for Spatial and Temporal Monitoring of Urban Forest and Vegetation Conditions: Case Study Zagreb, Croatia

Sustainability ◽

10.3390/su13116055 ◽

2021 ◽

Vol 13 (11) ◽

pp. 6055

Author(s):

Andrija Krtalić ◽

Dario Linardić ◽

Renata Pernar

Keyword(s):

Remote Sensing ◽

Forest Cover ◽

Urban Forest ◽

Vegetation Indices ◽

Field Measurements ◽

Unsupervised Classification ◽

Health Status Indicators ◽

Urban Ecosystem ◽

Management Decision

Urban forest and vegetation conditions are an important variable in urban ecosystem management decision-making. However, it is difficult to evaluate and monitor solely on the basis of field measurements. Remote sensing technologies can greatly contribute to the faster extraction and mapping of vegetation health status indicators, on the basis of which agronomy and forestry experts can draw conclusions about the condition of urban vegetation in larger areas. A new remote sensing-based urban forest and vegetation cover monitoring framework is presented and applied to a case study of the city of Zagreb, Croatia. In this study, Sentinel-2 multi-temporal imagery was used to derive and analyze the current state of urban forest cover. Vegetation indices (NDVI, RVI, and GRVI) were calculated. K-means unsupervised classification of the vegetation indices was conducted. In this way, the dimensionality of the vegetation indices was reduced, while all the data contained in it were used to represent their graded values. Vegetation that was in a poor condition stood out better that way. Finally, PCA-based change detection was performed on the vegetation indices graded values, and a map of change was produced. These results need to be interpreted and validated by foresters and agronomists in further research.

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Evaluating Urban Canopy Cover Before and After Housing Redevelopment in Falls Church, Virginia, USA

Arboriculture & Urban Forestry ◽

10.48044/jauf.2020.002 ◽

2020 ◽

Vol 46 (1) ◽

pp. 12-26

Author(s):

David Chojnacky ◽

Emily Smith-McKenna ◽

Laura Johnson ◽

John McGee ◽

Cindy Chojnacky

Keyword(s):

Local Governments ◽

Urban Forest ◽

Urban Canopy ◽

Canopy Cover ◽

Basal Area ◽

Field Measurements ◽

Tree Canopy ◽

Forest Recovery ◽

Tree Cover ◽

The City

Local governments have created regulations aimed to maintain and increase valuable urban tree cover. The City of Falls Church, Virginia, USA, requires each residential redevelopment to retain or plant enough trees for 20% canopy cover within ten years. To assess whether this goal is being met, we studied 21 Falls Church residential lots redeveloped between 1994 and 2011 where existing houses had been replaced with larger ones. Initial tree inventories and measurements prior to redevelopment were recorded in redevelopment plans. We remeasured preserved and planted trees in a ground survey and modeled tree canopy growth from a periodic tree diameter growth model linked to a model relating tree and crown diameters. Geospatial analysis was used to calculate nonoverlapping canopy cover within lots from crown diameter measurements and/or model predictions. We found that the City of Falls Church generally met its 20% canopy cover goal, but that the canopy cover metric alone is insufficient to fully describe urban forest recovery. Although canopy cover might recover rapidly from planting many small trees, recovery to the larger tree sizes that maximize ecosystem services can take much longer. Our modeling of lot-scale growth from field measurements showed the potential to manage forests using traditional diameter-based forest metrics that would relate results to canopy cover when needed. These forest stand metrics—based on basal area and trees per hectare—can account for tree size changes masked by the canopy cover metric.

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Modeling annual production and carbon fluxes of a large managed temperate forest using forest inventories, satellite data and field measurements

Tree Physiology ◽

10.1093/treephys/25.7.859 ◽

2005 ◽

Vol 25 (7) ◽

pp. 859-872 ◽

Cited By ~ 31

Author(s):

G. Le Maire ◽

H. Davi ◽

K. Soudani ◽

C. Francois ◽

V. Le Dantec ◽

...

Keyword(s):

Satellite Data ◽

Temperate Forest ◽

Field Measurements ◽

Carbon Fluxes ◽

Annual Production ◽

Forest Inventories

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Land use change and carbon fluxes in East Africa quantified using earth observation data and field measurements

Environmental Conservation ◽

10.1017/s0376892912000379 ◽

2012 ◽

Vol 40 (3) ◽

pp. 241-252 ◽

Cited By ~ 12

Author(s):

M. PFEIFER ◽

P.J. PLATTS ◽

N.D. BURGESS ◽

R.D. SWETNAM ◽

S. WILLCOCK ◽

...

Keyword(s):

East Africa ◽

Spatial Resolution ◽

Carbon Emissions ◽

Rapid Assessment ◽

Field Measurements ◽

Carbon Fluxes ◽

Landscape Scale ◽

Earth Observation ◽

Observation Data ◽

Vegetation Burning

SUMMARYCarbon-based forest conservation requires the establishment of ‘reference emission levels’ against which to measure a country or region's progress in reducing their carbon emissions. In East Africa, landscape-scale estimates of carbon fluxes are uncertain and factors such as deforestation poorly resolved due to a lack of data. In this study, trends in vegetation cover and carbon for East Africa were quantified using moderate-resolution imaging spectroradiometer (MODIS) land cover grids from 2002 to 2008 (500-m spatial resolution), in combination with a regional carbon look-up table. The inclusion of data on rainfall and the distribution of protected areas helped to gauge impacts on vegetation burning (assessed using 1-km spatial resolution MODIS active fire data) and biome trends. Between 2002 and 2008, the spatial extents of forests, woodlands and scrublands decreased considerably and East Africa experienced a net carbon loss of 494 megatonnes (Mt). Most countries in the area were sources of carbon emissions, except for Tanzania and Malawi, where the areal increase of savannah and woodlands counterbalanced carbon emissions from deforestation. Both Malawi and Tanzania contain large areas of planted forest. Vegetation burning was correlated with rainfall (forest only) and differed depending on land management. Freely available global earth observation products have provided ways to achieve rapid assessment and monitoring of carbon change hotspots at the landscape scale.

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Improving Occupants Comfort Through Qualitative Indoor Environments

Advances in Media, Entertainment, and the Arts - Cultural, Theoretical, and Innovative Approaches to Contemporary Interior Design ◽

10.4018/978-1-7998-2823-5.ch018 ◽

2020 ◽

pp. 387-404

Author(s):

Dalia Hafiz

Keyword(s):

Case Studies ◽

Collaborative Design ◽

Field Measurements ◽

Washington Dc ◽

Indoor Environments ◽

Visual Comfort ◽

Visual Discomfort ◽

Design Changes ◽

Space Dynamics

Daylight is one key aspect to enhance the sense of place and influence the personal interpretation and impression that last long after leaving the place. However, visual discomfort and glare can distract architects from achieving the most of daylighting. To better achieve visual comfort in daylit space time and space dynamics of the daylight condition, the representation and re-imagining of these dynamics need to be considered. This chapter explored a selected case study that was used for application: a daylit museum located in Washington DC Metropolitan was examined for visual discomfort problems. Since museums are typically carefully lit because of the sensitivity of exhibits, this case study evaluated the daylighting condition in a museum using a series of illuminance field measurements, simulations, and views experienced by occupants along a circulation path through the space. The case study also aimed at understanding how small design changes can affect visual comfort as a tactic for case studies. A collaborative design effort was used in different stages of the case study.

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