The recognition of a second breeding season in some migratory bird species by Rohwer et al. (1) creates an interesting scenario for conserving migratory bird populations. Previously, conservation biologists assessed sources as large undisturbed habitats and sinks as degraded breeding grounds (2), and treated fragmented and deforested habitats in nonbreeding “wintering” areas as drains on the po...

A substantial nitrate pool is stored within living cells in various benthic marine environments. The fate of this bioavailable nitrogen differs according to the organisms managing the intracellular nitrate (ICN). While some light has been shed on the nitrate carried by diatoms and foraminiferans, no study has so far followed the nitrate kept by gromiids. Gromiids are large protists and their IC...

We study the coupled complex Ginzburg-Landau (CGL) equations for traveling wave systems, and show that sources and sinks are the important coherent structures that organize much of the dynamical properties of traveling wave systems. We focus on the regime in which sources and sinks separate patches of left and righttraveling waves, i.e., the case that these modes suppress each other. We present...

Within-canopy profiles of ammonia (NH3) and measurements of the canopy turbulence characteristics were used to calculate the vertical source/sink density profile of NH3 and sensible heat in a mature oilseed rape (Brassica napus) canopy. For the analysis, the inverse Lagrangian technique (ILT) based on localized near-field theory was used. Turbulence was measured with a standard ultrasonic anemo...

The principal sources of chlorine in the MSW feed to WTE power plants are food wastes (e.g., wheat, green vegetables, melon, pineapple), yard wastes( leaves, grass, etc.), salt (NaCl), and chlorinated plastics (mostly polyvinyl chloride). Chlorine has important impacts on the WTE operation in terms of higher corrosion rate than in coal-fired power plants, formation of hydrochloric gas that must...

The chloroform flux through the environment is apparently constant at some 660+/-220 Ggyr(-1) (+/-1sigma) and about 90% of the emissions are natural in origin: the largest single source being in offshore sea water (contributing 360+/-90 Ggyr(-1)), with soil processes the next most important (220+/-100 Ggyr(-1)). Other natural sources, mainly volcanic and geological, account for less than 20 Ggy...

We modeled dissolved phytochelatin concentrations by studying its exudation from phytoplankton and its removal from seawater. Exudation rates were obtained from experiments in which a marine diatom, Thalassiosira pseudonana, was grown in Cd-containing medium. Dissolved phytochelatin in the culture medium was measured as a function of time, and a first-order model was fit to the data to derive e...

The wall-normal gradient of Reynolds shear stress, denoted ∂T+/∂y+, may be thought of as a momentum source or sink term (depending on its sign). This quantity represents a critical driver of the dynamics of wall-turbulence that give rise to the mean velocity distribution. While there have been a number of studies concerning the statistics of ∂T+/∂y+, there remains much to discover regarding the...

We investigate the electrical current and flow (number of parallel paths) between two sets of n sources and n sinks in complex networks. We derive analytical formulas for the average current and flow as a function of n. We show that for small n, increasing n improves the total transport in the network, while for large n bottlenecks begin to form. For the case of flow, this leads to an optimal n...