These uncertainties relate to: the lifetime distribution of fine roots; root lifetimes as a function of environmental conditions and plant species; and the sources and ages of C transferred to roots as a result of growth and maintenance14.
All in all, the finding of older C in chronologically younger roots challenges the conventional paradigm that different measurement techniques gather information about different ends of the root-lifetime continuum.
With our approach, we resolve the discrepancies between fine-root lifetimes estimated from 14C measurements and other methods used to study fine-root dynamics.
Inputs of C from roots into the soil are among the most uncertain components in forest ecosystems, with estimates of fine-root lifetimes ranging from months to decades2,3,4,5.
Secondly, without considering the time between C is fixed by plants and is used for root growth, radiocarbon-based studies quantifying fine-root lifetimes could largely underestimate the input of C from fine roots into the soil.
Previous studies suggested that an incomplete sampling of the youngest fine roots by destructive soil coring, as well as the difficulty of extracting the smallest fine roots from soil aggregates, might result in an overestimation of fine-root lifetimes via isotope measurements11.
In this paper, we consider Rooted Maximum Lifetime Broadcast/Convergecast problems in wireless settings.
Similar results are shown for the more general Rooted Maximum Lifetime Mixedcast problem, where in addition we are given an integer γ≥0, and the goal is to find the maximum integer k so that k Broadcast and γk Convergecast rounds can be performed.
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I've always had a healthy regard for the resource-constrained underdog – very likely the result of a lifetime rooting for the White Sox and my personal icon, Bill Veeck similar, for those not conversant in the National Pastime, to rooting for Anne Hathaway against Meryl Streep in The Devil Wore Prada).
