Dispersal and floating ability of dimorphic fruit segments of Cakile edentula var. lacustris

1981 ◽  
Vol 59 (12) ◽  
pp. 2595-2602 ◽  
Author(s):  
Anita M. Payne ◽  
M. A. Maun
Keyword(s):  
Water Waves ◽  
Sandy Beaches ◽  
Georgian Bay ◽  
New Locations ◽  
Waves And Currents ◽  
Cakile Edentula ◽  
Strong Winds

Cakile edentula (Bigel) Hook var. lacustris occurs abundantly along sandy beaches of Lakes Huron, Erie and Ontario. Until now the species had not been reported to occur along Georgian Bay but we located one population at Deanlea Beach. The deciduous upper fruit segments disperse long distances by water waves and currents and short distances by rolling caused by strong winds. The lower fruit segments usually remain attached to the parents which may be uprooted by high waves and then transported as tumble weeds to new locations. The floatation experiment showed that the agitation of jars containing the fruits improved their floating ability. Agitated upper fruit segments showed a significantly lower sinking index than agitated lower fruit segments and upper and lower fruit segments in the still treatment. The overwintering of fruits improved their floating ability.

scholarly journals Research on Separated Flow around A Submerged Horizontal Cylinder in Water Waves and Currents

1990 ◽  
Vol 1990 (168) ◽  
pp. 193-202
Author(s):  
Hisaaki Maeda ◽  
Koichi Masuda ◽  
Fumio Maruyama ◽  
Yuka Kitakouji
Keyword(s):  
Water Waves ◽  
Separated Flow ◽  
Horizontal Cylinder ◽  
Waves And Currents

Some aspects of nitrogen, phosphorus, and potassium nutrition of three colonizing beach species

1988 ◽  
Vol 66 (8) ◽  
pp. 1490-1496 ◽  
Author(s):  
Mary Ann Hawke ◽  
M. A. Maun
Keyword(s):  
Poor Response ◽  
Dry Weight ◽  
Plant Size ◽  
Sandy Beaches ◽  
Nutrient Concentrations ◽  
Oenothera Biennis ◽  
Potassium Nutrition ◽  
Cakile Edentula ◽  
Weedy Species ◽  
Phosphorus And Potassium

The culture of three colonizing dune species in hydroponics indicated that nitrogen (N), phosphorus (P), and potassium (K) were essential for high plant productivity. The K requirement of Oenothera biennis was lower than that of Cakile edentula or Corispermum hyssopifolium. The dry weight per plant of O. biennis was greater at higher concentrations of N, P, or K; however, the dry weight per plant of Cor. hyssopifolium was similar at all concentrations except in the complete absence of N, P, or K. Cakile edentula did not grow well under any of the nutrient concentrations, probably because of a poor response to hydroponic solutions. The number of live leaves and leaf area of O. biennis and Cor. hyssopifolium were affected more by a lack of N and P than K. The nutrient requirements of Cakile edentula were substantially higher than those of either O. biennis or Cor. hyssopifolium. It is suggested that the hierarchy in plant size and seed production in field populations may result from variability of available nutrients. Oenothera biennis, a generalist weedy species of farmland, old fields, waste places, and sandy beaches, was less exacting in its requirements of N, P, and K than the two beach specialists, Cakile edentula and Cor. hyssopifolium.

Nonlinear interactions between deep-water waves and currents

2011 ◽  
Vol 691 ◽  
pp. 1-25 ◽  
Author(s):  
R. M. Moreira ◽  
D. H. Peregrine
Keyword(s):  
Deep Water ◽  
Water Waves ◽  
Boundary Integral ◽  
Boundary Integral Method ◽  
Surface Velocity ◽  
Fully Nonlinear ◽  
Individual Wave ◽  
Waves And Currents ◽  
Wave Blocking ◽  
The Individual

AbstractThe effects of nonlinearity on a train of linear water waves in deep water interacting with underlying currents are investigated numerically via a boundary-integral method. The current is assumed to be two-dimensional and stationary, being induced by a distribution of singularities located beneath the free surface, which impose sharp and gentle surface velocity gradients. For ‘slowly’ varying currents, the fully nonlinear results confirm that opposing currents induce wave steepening and breaking within the region where a high convergence of rays occurs. For ‘rapidly’ varying currents, wave blocking and breaking are more prominent. In this case reflection was observed when sufficiently strong adverse currents are imposed, confirming that at least part of the wave energy that builds up within the caustic can be released in the form of partial reflection and wave breaking. For bichromatic waves, the fully nonlinear results show that partial wave blocking occurs at the individual wave components in the wave groups and that waves become almost monochromatic upstream of the blocking region.

The state of understanding of the effects of beach nourishment activities on coastal biogeochemical processes and conditions

Shore & Beach ◽  
2019 ◽  
pp. 46-57 ◽  
Author(s):  
Angelos Hannides ◽  
Nicole Elko ◽  
Kenneth Humiston
Keyword(s):  
Water Column ◽  
Chemical Reactions ◽  
Oxygen Demand ◽  
Sandy Beaches ◽  
Biogeochemical Processes ◽  
Policy Makers ◽  
Rapid Exchange ◽  
Waves And Currents ◽  
Oxygenated Water ◽  
The One

Sandy beaches are sites of significant exchange of matter and energy between water and sediment. This rapid exchange is attributed to the high permeability of sandy deposits and is one of the key ingredients in understanding how a given beach will respond to a nourishment event as a habitat for many important organisms. The response is driven by fundamental abiotically and biotically mediated chemical reactions that are profoundly affected by the ability of chemicals to accumulate or to be flushed out of a sandy column in the beach substrate. So while attention has correctly been paid to the effects of nourishment projects on infaunal communities and the upper levels of the food web, the chemical reactions connecting physics and geology on the one hand and ecology on the other are treated as a black box. We synthesize existing findings on biogeochemical processes at source areas and renourished beaches before, during, and after nourishment activities, and identify gaps in knowledge. Among other processes, we highlight how the exposure of reduced sediment to an oxic water column can initially increase oxygen demand, fuel microbial primary productivity, and drive the mobilization of potentially harmful contaminants. Restoration of oxic conditions in surficial sands can proceed rapidly through rapid exchange between sand and the oxygenated water column under the influence of physical forces, such as waves and currents, and high sand permeability. Based on our findings, we recommend foci for research, outreach, and broader impacts in this field as well as discuss coastal management needs for policy makers, planners, contractors, and the public to encourage information sharing.

THE MOVEMENT OF OIL SPILLS

1971 ◽  
Vol 1971 (1) ◽  
pp. 489-494 ◽  
Author(s):  
Henry G. Schwartzberg
Keyword(s):  
Wind Tunnel ◽  
Water Waves ◽  
Oil Spills ◽  
Wave Interaction ◽  
Open Water ◽  
Wind Drift ◽  
Calm Water ◽  
Waves And Currents ◽  
Infinite Height ◽  
Drift Analysis

ABSTRACT The effects of winds, waves, and currents, and the physical properties of oil and water on the drift rates of oil spills were studied in tests carried out in a combined water basin wind tunnel On calm water, oil drifted at a fairly constant percentage of the wind speed regardless of the nature and spreading tendencies of the oil, the spill size, and water temperature, depth, and salinity. Percent drift varied with wind tunnel height. Extrapolation to infinite height indicated that on calm open water wind drift should be 3.7%. Shallow water waves, which produced no significant drift themselves, reduced wind drift. Analysis indicated that deep water waves produced by the wind should produce significant drift, complicating wind drift prediction, but the magnitude of the wind wave interaction effects is not yet known. Test wind drifts and current drifts were found not to be directly additive.

Viscous effects on wave generation by strong winds

2008 ◽  
Vol 597 ◽  
pp. 343-369 ◽  
Author(s):  
A. ZEISEL ◽  
M. STIASSNIE ◽  
Y. AGNON
Keyword(s):  
Growth Rate ◽  
Water Waves ◽  
Friction Velocity ◽  
Viscous Effects ◽  
Significant Difference ◽  
Temporal And Spatial ◽  
Strong Winds ◽  
Numerical Solver ◽  
The Stability ◽  
Stability Of Water

This paper deals with the stability of water waves in a shear flow. Both temporal and spatial growth rates are derived. A carefully designed numerical solver enables us to extend the range of previous calculations, and to obtain results for larger wavelengths (up to 20 cm) and stronger winds (up to a friction-velocity of 1 m s−1). The main finding is the appearance of a second unstable mode which often turns out to be the dominant one. A comparison between results from the viscous model (Orr–Sommerfeld equations) and those of the inviscid model (Rayleigh equations), for 18 cm long waves, reveals some similarity in the structure of the eigenfunctions, but a significant difference in the imaginary part of the eigenvalues (i.e. the growth rate). It is found that the growth rate for the viscous model is 10 fold larger than that of the inviscid one.

Morphology and spatial distribution of alien sea-rockets (Cakile spp.) on South Australian and Western Canadian beaches

2004 ◽  
Vol 52 (2) ◽  
pp. 175 ◽  
Author(s):  
Timothy W. D. Cody ◽  
Martin L. Cody
Keyword(s):  
Western Europe ◽  
South Australia ◽  
Sandy Beaches ◽  
Eastern Coast ◽  
Species Boundaries ◽  
Western Canada ◽  
Annual Plants ◽  
Cakile Edentula ◽  
Petal Size ◽  
The Mediterranean Basin

Sea-rockets (Cakile spp., Brassicaceae) are annual plants of sandy beaches. Cakile edentula (Bigel.) Hook. is native to the eastern coast of North America, C. maritima Scop. to western Europe and the Mediterranean basin. The two species differ in several morphological features, including leaf form, fruits and petal size. Both are long-established aliens on beaches in western Canada and southern Australia, at sites where we examined their morphological and distributional attributes. The two Cakile species co-occur at Pachina Beach, British Columbia, Canada, with C. edentula more common and widely distributed over broader range of beach elevations and C. maritima restricted to the upper beach. Although a few putative hybrids occur, the species are morphologically quite distinct. In contrast, on Westlake Shores beach, South Australia, Cakile is at least in part perennial, with widely variable morphologies, and the taxon is not separable into two morphologically distinct entities. Species boundaries have blurred apparently because of introgression. Factors that may have lead to this contrasting situation in South Australia are discussed.

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