A study of long-term changes in some rocky shore communities in Orkney

1985 ◽  
Vol 87 (1-2) ◽  
pp. 47-63
Author(s):  
J. M. Baxter ◽  
A. M. Jones ◽  
J. A. Simpson
Keyword(s):  
Rocky Shore ◽  
Main Study ◽  
Seasonal Fluctuations ◽  
Percentage Cover ◽  
Mobile Species ◽  
Cyclic Patterns ◽  
A Site ◽  
Rocky Shore Communities ◽  
Canopy Algae

SynopsisThe distribution and relative abundance of various types of coastline are reviewed briefly. The results of a 9 year investigation of selected rocky shore communities are presented. Climatic parameters showed a marked variation during the study but were not correlated with the observed variations in flora and fauna. The main study was based on annual sampling of 8 bedrock shore transects using percentage cover or density for sessile and mobile species respectively. Seasonal fluctuations were studied in fixed areas at 2 sites over a 5 year period. Patterns of seasonal variation in various algal and faunal categories are described and discussed, canopy algae showed summer maxima while understorey species showed winter maxima. Annual studies showed species stability to be site specific: in species which showed marked, apparently cyclic, patterns of change, the changes were often asynchronous both between sites and, to a lesser degree, between stations at a site. The value of obtaining a measure of ‘patchiness’ is discussed.

Visual lures increase camera-trap detection of the southern cassowary (Casuarius casuarius johnsonii)

2017 ◽  
Vol 44 (3) ◽  
pp. 230 ◽  
Author(s):  
Wren R. McLean ◽  
Ross L. Goldingay ◽  
David A. Westcott
Keyword(s):  
Endangered Species ◽  
Camera Traps ◽  
Population Surveys ◽  
Monitoring Methods ◽  
Detection Rates ◽  
Mobile Species ◽  
Population Sizes ◽  
Cost Efficient ◽  
A Site

Context Monitoring is a key component in managing wildlife populations and is critical for revealing long-term population trends of endangered species. Cryptic or highly mobile species that occur in low densities and in remote terrain require the development of specific monitoring methods. The southern cassowary is an Australian endangered species that poses many challenges for conducting population surveys. Aims The aims of the present study were to determine the effectiveness of camera traps in detecting cassowaries at a site, to determine whether visual lures increased detection rates, and to explore the potential of camera traps in population surveys. Methods Coloured lures (mimicking large blue and red fruit) were placed in front of a set of camera traps and compared with controls (no lures) at 29 survey sites on the Daintree coast, northern Queensland, Australia. Key results Camera traps with lures (1) detected more birds, (2) had a shorter detection latency, (3) had a marginally greater number of captures, (4) experienced a longer capture duration, (5) were more likely to have the cassowary stop in front of the camera, and (6) achieved a 95% probability of detecting cassowaries in 12 trap days, compared with 28 trap days without lures. Conclusions An increase in the number of cassowaries detected, the reduction in camera latency times and the ability to identify the birds enables a more efficient approach to estimating population sizes over existing methods. This is the first published study to use visual lures to conduct camera trapping of birds. Implications The use of camera traps with lures is a practical and cost-efficient technique for the rapid detection of cassowaries at a site and lends itself to studies of population structure, size and trends.

Rocky shores monitoring programme

1995 ◽  
Vol 103 ◽  
pp. 181-200
Author(s):  
Jon Moore ◽  
Peter Taylor ◽  
Keith Hiscock
Keyword(s):  
Oil Spill ◽  
Rocky Shore ◽  
Graphical Analysis ◽  
Anthropogenic Effects ◽  
Rocky Shores ◽  
Physical Disturbance ◽  
Long Term Stability ◽  
Belt Transect ◽  
Rocky Shore Communities

SynopsisRocky shores in Sullom Voe were first surveyed in 1976 and, apart from a break of two years (1982–83), have been surveyed annually since. The aim of the surveys is to monitor the health of the rocky shore communities by identifying any major changes in the abundance of the fauna and flora and distinguishing anthropogenic effects from natural fluctuations. The 23 primary sites are spread around Sullom Voe, from Mavis Grind, at the head, to Mioness, just outside the entrance. A belt transect method is employed, and categorical abundances of conspicuous species on a checklist are recorded. Graphical analysis of the data for selected species and sites is presented to illustrate the most important changes that have been observed.The rocky shore communities in Sullom Voe are dynamically stable, except where physical disturbance has not allowed them to reach a state of long-term stability. The effects of, and the recovery from, the 1979 Esso Bernicia oil spill and its clean-up are described. While recovery of communities was rapid on shores where no clean-up was attempted, the communities on shores which were mechanically cleaned were showing continued effects in 1993. The deterioration of dogwhelk populations affected by the antifouling paint additive tributyltin (TBT) has been followed in recent years. Dogwhelk populations close to the terminal jetties are very small and are dominated by adults. Natural fluctuations in abundances of barnacles, dogwhelks, limpets, fucoid algae and littorinid gastropods over the period 1976 to 1992 are also described.

Time-Dependent Changes in Excitability After One-Trial Conditioning of Hermissenda

1997 ◽  
Vol 78 (6) ◽  
pp. 3460-3464 ◽  
Author(s):  
Terry Crow ◽  
Vilma Siddiqi
Keyword(s):  
Time Dependent ◽  
Control Group ◽  
Type B ◽  
Control Groups ◽  
Phototactic Behavior ◽  
Parallel Processes ◽  
Short And Long Term ◽  
A Site ◽  
Different Levels

Crow, Terry and Vilma Siddiqi. Time-dependent changes in excitability after one-trial conditioning of Hermissenda. J. Neurophysiol. 78: 3460–3464, 1997. The visual system of Hermissenda has been studied extensively as a site of cellular plasticity produced by classical conditioning. A one-trial conditioning procedure consisting of light paired with the application of serotonin (5-HT) to the exposed, but otherwise intact, nervous system produces suppression of phototactic behavior tested 24 h after conditioning. Short- and long-term enhancement (STE and LTE) of excitability in identified type B photoreceptors is a cellular correlate of one-trial conditioning. LTE can be expressed in the absence of STE suggesting that STE and LTE may be parallel processes. To examine the development of enhancement, we studied its time-dependent alterations after one-trial conditioning. Intracellular recordings from identified type B photoreceptors of independent groups collected at different times after conditioning revealed that enhanced excitability follows a biphasic pattern in its development. The analysis of spikes elicited by 2 and 30 s extrinsic current pulses at different levels of depolarization showed that enhancement reached a peak 3 h after conditioning. From its peak, excitability decreased toward baseline control levels 5–6 h after conditioning followed by an increase to a stable plateau at 16 to 24 h postconditioning. Excitability changes measured in cells from unpaired control groups showed maximal changes 1 h posttreatment that rapidly decremented within 2 h. The conditioned stimulus (CS) elicited significantly more spikes 24 h postconditioning for the conditioned group as compared with the unpaired control group. The analysis of the time-dependent development of enhancement may reveal the processes underlying different stages of memory for this associative experience.

scholarly journals Geobacter bemidjiensis sp. nov. and Geobacter psychrophilus sp. nov., two novel Fe(III)-reducing subsurface isolates

2005 ◽  
Vol 55 (4) ◽  
pp. 1667-1674 ◽  
Author(s):  
Kelly P. Nevin ◽  
Dawn E. Holmes ◽  
Trevor L. Woodard ◽  
Erich S. Hinlein ◽  
David W. Ostendorf ◽  
...  
Keyword(s):  
Type Strain ◽  
Novel Species ◽  
Electron Acceptors ◽  
Electron Donors ◽  
Amorphous Iron ◽  
Gram Negative ◽  
Subsurface Sediments ◽  
Curved Rods ◽  
A Site

Fe(III)-reducing isolates were recovered from two aquifers in which Fe(III) reduction is known to be important. Strain BemT was enriched from subsurface sediments collected in Bemidji, MN, USA, near a site where Fe(III) reduction is important in aromatic hydrocarbon degradation. Strains P11, P35T and P39 were isolated from the groundwater of an aquifer in Plymouth, MA, USA, in which Fe(III) reduction is important because of long-term inputs of acetate as a highway de-icing agent to the subsurface. All four isolates were Gram-negative, slightly curved rods that grew best in freshwater media. Strains P11, P35T and P39 exhibited motility via means of monotrichous flagella. Analysis of the 16S rRNA and nifD genes indicated that all four strains are δ-proteobacteria and members of the Geobacter cluster of the Geobacteraceae. Differences in phenotypic and phylogenetic characteristics indicated that the four isolates represent two novel species within the genus Geobacter. All of the isolates coupled the oxidation of acetate to the reduction of Fe(III) [iron(III) citrate, amorphous iron(III) oxide, iron(III) pyrophosphate and iron(III) nitrilotriacetate]. All four strains utilized ethanol, lactate, malate, pyruvate and succinate as electron donors and malate and fumarate as electron acceptors. Strain BemT grew fastest at 30 °C, whereas strains P11, P35T and P39 grew equally well at 17, 22 and 30 °C. In addition, strains P11, P35T and P39 were capable of growth at 4 °C. The names Geobacter bemidjiensis sp. nov. (type strain BemT=ATCC BAA-1014T=DSM 16622T=JCM 12645T) and Geobacter psychrophilus sp. nov. (strains P11, P35T and P39; type strain P35T=ATCC BAA-1013T=DSM 16674T=JCM 12644T) are proposed.

Bedforms, bed material, and bedload transport in a salt-wedge estuary: Fraser River, British Columbia

1989 ◽  
Vol 26 (7) ◽  
pp. 1440-1452 ◽  
Author(s):  
R. A. Kostaschuk ◽  
M. A. Church ◽  
J. L. Luternauer
Keyword(s):  
British Columbia ◽  
River Discharge ◽  
Bedload Transport ◽  
Fraser River ◽  
Seasonal Fluctuations ◽  
Salt Wedge ◽  
Migration Rates ◽  
Material Load ◽  
Bed Material

The lower main channel of the Fraser River, British Columbia, is a sand-bed, salt-wedge estuary in which variations in velocity, discharge, and bedform characteristics are contolled by river discharge and the tides. Bed-material composition remains consistent over the discharge season and in the long term. Changes in bedform height and length follow but lag behind seasonal fluctuations in river discharge. Migration rates of bedforms respond more directly to river discharge and tidal fall than do height and length. Bedform characteristics were utilized to estimate bedload transport in the estuary, and a strong, direct, but very sensitive relationship was found between bed load and river discharge. Annual bedload transport in the estuary is estimated to be of the order of 0.35 Mt in 1986. Bedload transport in the estuary appears to be higher than in reaches upstream, possibly because of an increase in sediment movement along the bed to compensate for a reduction in suspended bed-material load produced by tidal slack water and the salt wedge.

scholarly journals Redox Oxides-Based Solar Thermochemistry and Its Materialization to Reactor/Heat Exchanger Concepts for Efficient Solar Energy Harvesting, Transformation and Storage

2019 ◽  
Vol 141 (2) ◽  
Author(s):  
Christos Agrafiotis ◽  
Mathias Pein ◽  
Dimitra Giasafaki ◽  
Stefania Tescari ◽  
Martin Roeb ◽  
...  
Keyword(s):  
Scanning Calorimetry ◽  
Chemical Expansion ◽  
Solar Energy Harvesting ◽  
Cyclic Operation ◽  
Heat Effects ◽  
Carbon Dioxide Splitting ◽  
Oxygen Pumping ◽  
Coefficient Of Linear Expansion ◽  
A Site

Ca-Mn-based perovskites doped in their A- and B-site were synthesized and comparatively tested versus the Co3O4/CoO and (Mn,Fe)2O3/(Mn,Fe)3O4 redox pairs with respect to thermochemical storage and oxygen pumping capability, as a function of the kind and extent of dopant. The perovskites' induced heat effects measured via differential scanning calorimetry are substantially lower: the highest reaction enthalpy recorded by the CaMnO3–δ composition was only 14.84 kJ/kg compared to 461.1 kJ/kg for Co3O4/CoO and 161.0 kJ/kg for (Mn,Fe)2O3/(Mn,Fe)3O4. Doping of Ca with increasing content of Sr decreased these heat effects; more than 20 at % Sr eventually eliminated them. Perovskites with Sr instead of Ca in the A-site exhibited also negligible heat effects, irrespective of the kind of B site cation. On the contrary, perovskite compositions characterized by high oxygen release/uptake can operate as thermochemical oxygen pumps enhancing the performance of water/carbon dioxide splitting materials. Oxygen pumping via Ca0.9Sr0.1MnO3–δ and SrFeO3–δ doubled and tripled, respectively, the total oxygen absorbed by ceria during its re-oxidation versus that absorbed without their presence. Such effective pumping compositions exhibited practically no shrinkage during one heat-up/cool-down cycle. However, they demonstrated an increase of the coefficient of linear expansion due to the superposition of “chemical expansion” to thermal-only one, the effect of which on the long-term dimensional stability has to be further quantified through extended cyclic operation.

Long-term evaluation of coal fly ash and mine tailings co-placement: A site-specific study

2009 ◽  
Vol 91 (1) ◽  
pp. 237-244 ◽  
Author(s):  
Muluken B. Yeheyis ◽  
Julie Q. Shang ◽  
Ernest K. Yanful
Keyword(s):  
Fly Ash ◽  
Mine Tailings ◽  
Coal Fly Ash ◽  
Site Specific ◽  
Specific Study ◽  
Term Evaluation ◽  
A Site
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