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Seasonal litter fall and changes in dry weight and minerals within the litter layer were sampled throughout one year. The annual total litter fall was 4.9 t per hectare of which 70% was leaf fall. Litter fall was highest in spring and early summer, the falls of each component (leaf, wood, etc.) and species being markedly seasonal but not all in phase. The(More)
Two adjacent coastal ecosystems, dry sclerophyll scrub and introduced grassland, were sampled two (grassland) or three (scrub) times throughout one year to estimate total and component dry matter and mineral contents. The soil was the major mineral pool in both ecosystems and contained at least 60% of all minerals except potassium. The scrub live plus dead(More)
The dynamics of transport at the edge of magnetized plasmas is deterministic chaos. The connection is made by a previous survey [M. A. Pedrosa et al., Phys. Rev. Lett. 82, 3621 (1999)] of measurements of fluctuations that is shown to exhibit power spectra with exponential frequency dependence over a broad range, which is the signature of deterministic(More)
Pulses having a temporal Lorentzian shape arise naturally from topological changes in flow trajectories or phase-space orbits associated with deterministic chaos. The pulses can appear as random intermittent events in the time series of observable quantities, and they are the cause of exponential frequency power spectra previously observed in magnetically(More)
Measurements of a magnetized plasma with a controlled electron temperature gradient show the development of a broadband spectrum of density and temperature fluctuations having an exponential frequency dependence at frequencies below the ion cyclotron frequency. The origin of the exponential frequency behavior is traced to temporal pulses of Lorentzian(More)
Azimuthal flow is driven in the edge of the Large Plasma Device LAPD W. Gekelman et al., Rev. Sci. Instrum. 62, 2875 1991 through biasing a section of the vacuum vessel relative to the plasma source cathode. As the applied bias exceeds a threshold, a transition in radial particle confinement is observed, evidenced by a dramatic steepening in the density(More)
An experimental investigation of the low-frequency density fluctuations in the plasma edge region of the TJ-K stellarator [N. Krause et al., Rev. Sci. Inst. 73, 3474 (2002)] finds that the ensembleaveraged frequency spectra exhibit a near exponential frequency dependence whose origin can be traced to individual pulses having a Lorentzian temporal shape.(More)
A two-dimensional fractional Laplacian operator is derived and used to model nonlocal, nondiffusive transport. This integro-differential operator appears in the long-wavelength, fluid description of quantities undergoing non-Brownian random walks without characteristic length scale. To study bounded domains, a mask function is introduced that modifies the(More)
Coherent temperature oscillations corresponding to thermal (diffusion) waves are observed to be spontaneously excited in a narrow temperature filament embedded in a large, but colder, magnetized plasma. The parallel and transverse propagation properties of the waves satisfy the predictions of the classical transport theory based on Coulomb collisions. The(More)
The outer region of the plasma column of a large, linear plasma device is rotated in a controlled fashion by biasing a section of the vacuum chamber wall positive with respect to the cathode Er 0 . The magnitude and temporal dependence of the observed cross-field current, produced when the bias voltage is applied, is consistent with ion current arising from(More)