20150107

Author : Jassal, R. S. Black, T. A. Novak, M. D. Gaumont-Guay, D. Nesic, Z.
Year : 2008
Title : Effect of soil water stress on soil respiration and its temperature sensitivity in an 18-year-old temperate Douglas-fir stand
Journal : Global Change Biology
Comment : They found that an exponential (van’t Hoff type) model with Q10 and R10 dependent on only VWC explained 92% of the variance in half-hourly values of RS, including the period with soilwater stress conditions.
The absolute temperature sensitivity of RS (i.e. dRS/dTS) increased with VWC (at the 4 cm soil depth) up to 0.15 m3 m-3, above which it slowly declined. The value of dRS/dTS was nearly 0 for VWC < 0.08 m3 m-3, thereby confirming that RS was largely unaffected by temperature under soil water stress conditions. The Q10 and R10 to VWC not only accounted for the effects of TS on RS and its temperature sensitivity but also accounted for the seasonality of biotic (photosynthesis, root activity, and litterfall) and abiotic (soil moisture and temperature) controls and their interactions.

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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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The concurrent decline of soil lead and children’s blood lead in New Orleans

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The concurrent decline of soil lead and children’s blood lead in New Orleans Howard W. Mielke ,  Christopher R. Gonzales ,  Eric T. Powell ,  Mark A. S. Laidlaw ,  Kenneth J. Berry ,  Paul W. Mielke  Jr. , and  Sara Perl Egendorf PNAS  first published October 14, 2019  https://doi.org/10.1073/pnas.1906092116 Significance The inextricable link between topsoil lead (Pb) and children’s blood lead (BPb) has not been widely accepted. Pb is associated with multiple health adversities. Urban residents are at risk from exposure to legacy Pb dust in topsoil resulting from smelting, industrial discharges, leaded gasoline emissions, leaded paint, and incineration. In New Orleans, topsoil median Pb decreased in ∼15 y from 99 mg/kg to 54 mg/kg, or ∼2.4 mg⋅kg⋅y −1 . In ∼12 y, children’s median BPb declined from 3.6 μg/dL to 1.3 μg/dL, or ∼0.2 μg⋅dL⋅y −1 . We argue that depletion of topsoil Pb is an important factor in the continuous dec...
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