20130625

Author : Xu, L. K. Furtaw, M. D. Madsen, R. A. Garcia, R. L. Anderson, D. J. McDermitt, D. K.
Year :  2006
Title : On maintaining pressure equilibrium between a soil CO2 flux chamber and the ambient air
Journal : Journal of Geophysical Research-Atmospheres
Comment :  In previous studies, a simple vent tube connecting to the chamber has often been used to maintain pressure equilibrium. This approach, however, can be effective only under calm conditions. Under windy conditions, negative pressure excursions will occur inside the chamber that are artifacts resulting from wind passing over the vent tube's external open end, a phenomenon known as the Venturi effect. This causes anomalous mass flow of CO2-rich air from the soil into the chamber, leading to a significant overestimation of FCO2. They also present a new vent design for a soil CO2 flux chamber capable of maintaining pressure equilibrium between inside the chamber and the ambient air outside the chamber under both calm and windy conditions.

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20131218

Author  : Edmondson, J. L. Davies, Z. G. McHugh, N. Gaston, K. J. Leake, J. R. Year  : 2012 Title  : Organic carbon hidden in urban ecosystems Journal  : Scientific Reports Comment   : To date, the total quantity of OC stored in urban soils (under both impervious surfaces and greenspaces), together with that in above-ground vegetation, has never been systematically measured.  They report the first city-wide organic carbon (OC) budget for vegetation and soils, including under impervious surfaces. The majority of OC (82%) was held in soils, with 13% found under impervious surfaces, and 18% stored in vegetation.
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20140731

Author  : Chen, Y. J. Day, S. D. Shrestha, R. K. Strahm, B. D. Wiseman, P. E. Year  : 2014 Title  : Influence of urban land development and soil rehabilitation on soil-atmosphere greenhouse gas fluxes Journal  : Geoderma Comment   : Typical land development practices did not increase global warming potential (GWP) when compared to undeveloped land. Post-development soil rehabilitation, however, resulted in greater GWP than both undisturbed soils and those subjected to typical development practices driven primarily by increased CO2 efflux.
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Biogeographic patterns in below-ground diversity in New York City’s Central Park are similar to those observed globally

Kelly S. Ramirez1 , Jonathan W. Leff4,5, Albert Barbera´n5 , Scott Thomas Bates6 , Jason Betley7 , Thomas W. Crowther8 , Eugene F. Kelly2 , Emily E. Oldfield8 , E. Ashley Shaw3 , Christopher Steenbock4 , Mark A. Bradford8 , Diana H. Wall1,3 and Noah Fierer4,5 Soil biota play key roles in the functioning of terrestrial ecosystems, however, compared to our knowledge of above-ground plant and animal diversity, the biodiversity found in soils remains largely uncharacterized. Here, they present an assessment of soil biodiversity and biogeographic patterns across Central Park in New York City that spanned all three domains of life, demonstrating that even an urban, managed system harbours large amounts of undescribed soil biodiversity. Despite high variability across the Park, below-ground diversity patterns were predictable based on soil characteristics, with prokaryotic and eukaryotic communities exhibiting overlapping biogeographic patterns. Further, Central Park soils harboured nearly ...
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