The effect of pedal mucus on barnacle cyprid settlement: a source for indirect interactions in the rocky intertidal?

Laboratory assessment of barnacle cyprid settlement showed that it was increased by a multiple of ∼6 and by a multiple of ∼3 by the pedal mucus produced by Patella vulgata and by Littorina littorea, respectively. Field experiments showed that pedal mucus produced by P. vulgata could increase cyprid settlement by a multiple of ∼4, but that there was no effect of the pedal mucus produced by L. littorea. Evaluation of the effect of pedal mucus coated with nitro-cellulose and various pedal extracts, on cyprid settlement, ascertained that there appeared to be no chemotactic or chemotaxic effect of pedal mucus on cyprid settlement. In contrast, the use of a physical analogue to pedal mucus, silicon grease, increased cyprid settlement by a multiple of ∼18. Pedal mucus produced by P. vulgata and by L. littorea increased the time spent by cyprids in surface suitability testing by a multiple of ∼10 and ∼3, respectively. Only the pedal mucus produced by P. vulgata had any effect on the exploratory behaviour of cyprids increasing the time spent on this behaviour by a multiple of ∼3. Pedal mucus affects the settlement of cyprids through adhesive enmeshment, resulting in positive feedback to the mechanoreceptors housed in the antennules of cyprids, in what is effectively a settlement cascade. Pedal mucus produced by P. vulgata and L. littorea can affect the settlement of the majority of settling marine organisms through physical entrapment. Pedal mucus produced by L. littorea will have little, if any, effect on the settlement of organisms in the field whereas the pedal mucus produced by P. vulgata may be of major importance in determining the adult distribution patterns.

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The surface characteristics of pedal mucus: a potential aid to the settlement of marine organisms?

Journal of the Marine Biological Association of the United Kingdom ◽

10.1017/s0025315402005246 ◽

2002 ◽

Vol 82 (1) ◽

pp. 131-139 ◽

Cited By ~ 4

Author(s):

Sebastian P. Holmes ◽

Andrew Cherrill ◽

Mark S. Davies

Keyword(s):

Size Range ◽

Surface Characteristics ◽

Marine Organisms ◽

Littorina Littorea ◽

Patella Vulgata ◽

Settlement Site ◽

Silicon Grease

Surface characteristics including wettability, thickness and adhesive potential of the pedal mucus produced by Patella vulgata and Littorina littorea were measured, to determine their effects on the settlement of marine organisms. The pedal mucus produced by P. vulgata was less wettable than that produced by L. littorea. For organisms that prefer to settle on hydrophobic substrata the pedal mucus produced by P. vulgata would be their preferred settlement site. The pedal mucus produced by stationary P. vulgata was thicker (mean thickness±SE=0·37±0·004 mm) than the pedal mucus produced by mobile P. vulgata and/or that produced by L. littorea, neither of which differed in their thickness (mean thickness±SE =0·10±0·01 mm). The pedal mucus produced by P. vulgata had a greater adhesive potential (mean force of adhesion for the size range of mimics examined=3715–5380 Nm2) than the pedal mucus produced by L. littorea (mean force of adhesion for the size range of mimics examined=2846–3361 Nm2). Comparison of the adhesive potential of the pedal mucuses with a pedal mucus analogue, silicon grease, suggests that the pedal mucuses function as a Stefan (1874) adhesive when adhering organisms.

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Consistent spatial distribution patterns of bacterial communities revealed by serial time-archived soils from long-term field experiments

Soil Biology and Biochemistry ◽

10.1016/j.soilbio.2019.02.020 ◽

2019 ◽

Vol 133 ◽

pp. 137-145 ◽

Cited By ~ 1

Author(s):

Jie Liu ◽

Zhiying Guo ◽

Aiai Xu ◽

Changkun Wang ◽

Shiwen Wu ◽

...

Keyword(s):

Spatial Distribution ◽

Bacterial Communities ◽

Field Experiments ◽

Distribution Patterns ◽

Spatial Distribution Patterns ◽

Term Field

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A REVIEW OF EXPERIMENTAL SHORELINE OIL SPILLS

International Oil Spill Conference Proceedings ◽

10.7901/2169-3358-1993-1-583 ◽

1993 ◽

Vol 1993 (1) ◽

pp. 583-590 ◽

Cited By ~ 4

Author(s):

J. M. Baker ◽

D. I. Little ◽

E. H. Owens

Keyword(s):

Research And Development ◽

Oil Spill ◽

Field Experiments ◽

Oil Spills ◽

Toxicity Testing ◽

Ecological Effects ◽

Rocky Intertidal ◽

Habitat Types ◽

Shoreline Protection ◽

Oil Type

ABSTRACT Oil spill research and development has involved a large number of experiments to evaluate the effectiveness and the effects of marine shoreline protection and cleanup techniques. Considerable knowledge has accumulated from laboratory and wave tank studies, and there have also been a number of field experiments, in which oil was intentionally spilled on shorelines under controlled conditions. This review summarizes those field experiments, which are grouped in five major habitat types: rocky intertidal, cobble/pebble/gravel, sand/mud, saltmarshes, and mangroves/seagrasses. Tables included in the paper itemize the oil type and volume, location and substrate character, number and size of plots, response techniques tested, and referenced publications. This information is then used to combine understanding of the effectiveness of cleanup with understanding of the ecological effects of cleanup methods, compared with those of untreated oil. It is very difficult to achieve this type of information and understanding from toxicity testing or from spills of opportunity.

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Studies on Influence of Emitter Discharge Rate, Irrigation Supplies and Planting Pattern on Tomato in Heavy Soils Of Central India

Cercetari Agronomice in Moldova ◽

10.2478/v10298-012-0004-y ◽

2012 ◽

Vol 45 (1) ◽

pp. 47-58

Author(s):

P. Shrivastava ◽

G. Rajput ◽

A. Pandey

Keyword(s):

Field Experiments ◽

Discharge Rate ◽

Central India ◽

Distribution Patterns ◽

Moisture Distribution ◽

Tomato Crop ◽

Planting Pattern ◽

Micro Irrigation ◽

Soil Moisture Distribution ◽

Emitter Discharge

Studies on Influence of Emitter Discharge Rate, Irrigation Supplies and Planting Pattern on Tomato in Heavy Soils Of Central IndiaField experiments were conducted during two post rainy seasons at J.N. Krishi Vishwa Vidyalaya, Jabalpur, India, to evaluate the effect of emitter discharge rate, drip irrigation supplies and planting pattern on soil moisture distribution patterns and yield of tomato in heavy soils. In the experiments during 1998, irrigation was applied through emitters (2, 4 lhr-1) and micro-tubes (6 lhr-1) to conventional and paired-row plantings of tomato (var. ACC - 99). While, in the experiments during 2000, four irrigation supply levels (0.6, 0.8, 1.0, 1.2 times crop evapo-transpiration) combined with paired-row, four-row plantings of tomato (var. Pusa ruby) were applied. Observations revealed that fulfillment of 100 per cent of tomato crop evapo-transpiration need utilizing micro-irrigation (micro-tubes of rated discharge - 6 lhr-1) combined with four-row plantings of tomato achieved a cost saving of 35.21 per cent on initial investment with significant gain in yield over paired-row planting in the heavy soils of central India.

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Numerical Simulation of Biological Impact in Direct Injection of Carbon Dioxide in the Ocean

23rd International Conference on Offshore Mechanics and Arctic Engineering, Volume 3 ◽

10.1115/omae2004-51064 ◽

2004 ◽

Author(s):

Toru Sato

Keyword(s):

Carbon Dioxide ◽

Field Experiments ◽

Direct Injection ◽

Computational Simulation ◽

Marine Organisms ◽

Small Scale ◽

Logarithmic Scale ◽

High Concentration ◽

Biological Impact ◽

Simulation Code

Direct injection of carbon dioxide (CO2) in the deep ocean is one of the promising ways to mitigate the global warming. One of uncertainties in this method is, however, its impact on marine organisms in the near field before CO2 is diluted widely in the ocean. Since field experiments cost enormously, computational simulations are alternatively expected to show detailed information on the dilution process near injection points and its impact on marine organisms. In general, for testing acute impact of some toxicity on organisms, the LC50 concept is widely used. As a biological impact model, we, therefore, consider mortality that reflects the recent laboratory experiment of fish and zooplankton for various concentration of CO2. Here we regard the sigmoid-transferred mortality as a linear function of time in the logarithmic scale, not alone of the concentration of CO2 in the logarithmic scale. This model can easily be applied to unsteady CO2 experience for marine organisms. The model was installed in a computational simulation code for the reconstruction of small-scale ocean turbulence. Its results suggested that the effect is not nontrivial when CO2 of 0.1ton/sec is injected in the form of spray by 100 nozzles provided vertically on a pipe with 10m interval. This is because of the initial high concentration of CO2 near the injection points. It is, therefore, necessary to develop effective engineering measures for the initial dilution.

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Use of Stable Element Distribution Patterns for Predicting Distribution of Radionuclides in Marine Organisms

BioScience ◽

10.2307/1294863 ◽

1969 ◽

Vol 19 (12) ◽

pp. 1082-1085

Author(s):

Robert Y. Ting

Keyword(s):

Distribution Patterns ◽

Element Distribution ◽

Marine Organisms ◽

Stable Element ◽

Element Distribution Patterns

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Spatial covariance reverses the compound effect of multiple stressors on rocky shore biofilm

10.22541/au.162030515.58929880/v1 ◽

2021 ◽

Author(s):

Luca Rindi ◽

JIANYU HE ◽

Lisandro Benedetti-Cecchi

Keyword(s):

Field Experiments ◽

Photosynthetic Activity ◽

Multiple Stressors ◽

Nonlinear Effects ◽

Sediment Deposition ◽

Rocky Intertidal ◽

Climate Variables ◽

Spatial Covariance ◽

Earth’S Climate ◽

Compound Effect

Understanding how multifactorial fluctuating environments affect species and communities remains one of the major challenges in ecology. Here, we use field experiments and simulations to assess the influence of nonlinear effects and spatial covariation of two important climate variables – warming and sediment deposition – on the biomass and photosynthetic activity of rocky intertidal biofilm. Simulations stemming from an experimentally derived response surface showed how the degree and direction of spatial covariation between warming and sediment deposition ultimately determined the nonlinear response of biofilm biomass (but not photosynthetic activity) to fluctuating levels of the two climate variables. Experimental results corroborated these predictions, probing the buffering effect of negative spatial covariation against extreme levels of warming and sediment deposition. Together, these results indicate that consideration of local-scale patterns of covariation between climate drivers can improve our understanding and ability to predict ecological responses to ongoing and future changes in Earth’s climate.

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First visual record of rare purple-colored dogwhelks (Nucella lapillus) on the Atlantic coast of Nova Scotia, Canada

F1000Research ◽

10.12688/f1000research.9707.2 ◽

2017 ◽

Vol 5 ◽

pp. 2435

Author(s):

Sonja M. Ehlers ◽

Julius A. Ellrich

Keyword(s):

Nova Scotia ◽

Field Experiments ◽

Atlantic Coast ◽

Rocky Intertidal ◽

Bay Of Fundy ◽

Nucella Lapillus ◽

Shell Color ◽

The North ◽

Intertidal Gastropod ◽

Visual Record

The dogwhelk Nucella lapillus is a rocky intertidal gastropod of the North Atlantic coast. Individual shell color varies. Common colors range between white and brown, with darker dogwhelks being more affected by heat stress than lighter-colored conspecifics. Other reported shell colors are purple, black, mauve, pink, yellow, and orange from UK coasts, red and gray from the Bay of Fundy coast of New Brunswick and Nova Scotia (Canada), and purple, black, gray, yellow, and orange from the coasts of Maine and Massachusetts (USA), with purple being considered as a rare color. On the Atlantic coast of Nova Scotia, dogwhelks are active from April until November, but information on dogwhelk shell color is missing for this coast. On 16 June 2016, we found two purple-colored dogwhelks in the mid-to-high intertidal zone of a moderately wave-exposed rocky shore near Duncans Cove, on the Atlantic coast of Nova Scotia while collecting dogwhelks (n= 1000) during low tide for manipulative field experiments. All other dogwhelks collected on that day were of common white and brown colors. During earlier dogwhelk collections in Atlantic Nova Scotia (between 2011-2013) and field surveys in Duncans Cove (between 2014-2016), we did not find any purple-colored dogwhelks, indicating the rareness of this color in that region. Apparently, our observations provide the first visual record of rare purple-colored dogwhelks on the Atlantic coast of Nova Scotia, Canada.

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Field Experiments of Preferential Attachment

The Oxford Handbook of Social Networks ◽

10.1093/oxfordhb/9780190251765.013.20 ◽

2020 ◽

pp. 383-391

Author(s):

Arnout van de Rijt ◽

Afife Idil Akin

Keyword(s):

Positive Feedback ◽

Field Experiments ◽

Preferential Attachment ◽

Control Group ◽

Network Growth ◽

Experimental Strategy

The preferential attachment hypothesis posits that a node’s propensity to be linked to by other nodes increases with the number of incoming links it has already accumulated. Compellingly demonstrating the presence of such positive feedback in connectivity in longitudinal records is made difficult by confounding temporal processes and unobserved nodal attributes. This challenge can be addressed with a field experimental strategy in which the experimenter bestows links upon random nodes and compares subsequent attachment to these experimental nodes to a control group. In recent studies the authors reported on four such field experiments representing distinct empirical environments and theoretical contexts. In each environment the hypothesis was confirmed, suggesting that preferential attachment is a common feature of network growth in many contexts. This chapter presents results from a novel test in a fifth environment, eBay, where preferential attachment was again found to operate.

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