bluuebunny/crossref_metadata_2025_split huggingface dataset:
Continuous plankton records: the distribution and standing crop of the plankton of the shelf and ocean to the west of the British Isles
Authors: Colebrook J. M. 
Published: March 2014

SynopsisData from the Continuous Plankton Recorder survey are used to compare the distribution and seasonal and year-to-year variations in the abundance of the plankton of the area of the Rockall Channel with both the shelf and the adjacent oceanic areas. It is argued that the distribution and size of overwintering stocks of zooplankton provide the key to understanding the dynamics of the plankton of this area.It would appear that, due to inherent limitations to the net rate of increase of zooplankton populations, the distribution of the overwintering stocks has an influence on the distribution and abundance of most species through the rest of the year. This affects the dynamics of the seasonal cycle and also influences the form of year-to-year changes in abundanceThe plankton of the area of the Rockall Channel is characterised by low overwintering stocks, coupled in spring with higher rates of population increase as compared with the adjacent shelf. There is a pronounced spring bloom of phytoplankton, which does not appear to be controlled by grazing, followed by a period of nearly five months of relative stability of stocks of both phytoplankton and zooplankton. It is suggested that during this period the zooplankton graze the daily production of phytoplankton, the growth of which is determined to a large extent by nutrients recycled from the zooplankton. The effects of this pattern of dynamics on the form of year-to-year changes in the abundance of the plankton over the last few decades is discussed.
Seasonal deposition of phytodetritus to the deep-sea floor
Authors: Rice A. L. , Billett D. S. M. , Fry J. , John A. W. G. , Lampitt R. S. , Mantoura R. F. C. , Morris R. J. 
Published: March 2014

SynopsisEvidence has accumulated over the past twenty years to suggest that the deep-sea environment is not as constant as was at one time thought, but exhibits temporal variations related to the seasonally in the overlying surface waters. Recent results from deep-moored sediment traps suggest that this coupling is mediated through the sedimentation of organic material, while observations in the Porcupine Seabight indicate that in this region, at least, there is a major and rapid seasonal deposition of aggregated phytodetritus to the sea-floor at slope and abyssal depths.This paper summarises the results of the Porcupine Seabight studies over the past five years or so, using time-lapse sea-bed photography and microscopic, microbiological and chemical analyses of samples of phytodetritus and of the underlying sediment. The data are to some extent equivocal, but they suggest that the seasonal deposition is a regular and dramatic phenomenon and that the material undergoes relatively little degradation during its passage through the water column. The mechanisms leading to the aggregation of the phytodetritus have not been identified, and it is not yet known whether the phenomenon is geographically widespread nor whether it is of significance to the deep-living mid-water and benthic communities.
Oceanographic observations in Sullom Voe, Shetland in the period 1974–78
Authors: Dooley H. D. 
Published: March 2014

SynopsisIn the five years to 1978 hydrographic surveys were conducted in Sullom Voe, Shetland and these have been supplemented since 1976 by current measurements. Conditions varied from year to year mainly due to climatic factors, the most marked changes occurring at the head of the voe where varying degrees of stagnation were encountered.In summer the voe is weakly stratified. In winter longitudinal gradients are encountered mainly because of a slight reduction in salinity towards the head. Because of this the surface waters of the voe are more readily flushed in summer than in winter when the flushing time, calculated from the freshwater balance, is at least 15 days. The current measurements show that rapid renewal of the surface waters occurs in the summer during storms. Because the voe is open to the north, southerly winds, blowing surface waters out of the voe, drive a much stronger circulation than winds from the north and this is the main reason for the intermittent breakdown of stagnation in the upper basin. Tidal currents are very weak (<7 cm/s) but occasionally seiches, generated by sudden changes in the wind direction, with a period of about 1 hour and current amplitude of 15 cm/s are encountered. Nutrients from the adjacent tidally mixed Yell Sound are intermittently supplied to the voe by these wind-driven processes and as a result, high levels of productivity are encountered at intervals throughout the summer.
Tidal currents in Yell Sound and the outer regions of Sullom Voe
Authors: Blackman D. L. , Graff J. , Vassie J. M. 
Published: March 2014

SynopsisCurrents were measured along two routes through Yell Sound to Sullom Voe in the Shetland Islands. Current meter moorings were deployed by the consulting engineers Peter Fraenkell and Partners for one month at 20 positions with three meters which measured the flow from near surface to a depth of 20 metres. The accuracy of these measurements is considered and the difficulty of making measurements in this region is illustrated.The paper discusses the nature and variability of the currents that were measured and resolves the currents into a tidal and non-tidal component. An analysis procedure is developed for removing the tidal component and for producing tidal current vectors for each position. From this the general tidal circulation pattern is constructed and discussed. It is shown that tidal currents along the eastern route are too high at certain states of the tide for safe navigation.Current surges of significant magnitude are shown to exist throughout the area. These are driven by the tidal motion and it is suggested that they are an effect of travelling gyres which are generated in the lee of islands and shallow banks when the tidal streams are largest.
Analysis of hydrocarbons in sediments as indicators of pollution
Authors: Douglas A. G. , Hall P. B. , Bowler B. , Williams P. F. V. 
Published: March 2014

SynopsisAfter a brief review of some general procedures that have been proposed for the identification of oil spills, details are given of methods that depend on hydrocarbon analyses. Hydrocarbon distributions due to a biological input are compared to those from a petroleum input, utilising hydrocarbon fingerprints obtained by gas chromatographic and combined gas chromatographic-mass spectrometric methods.It has been shown that most of the sediment samples collected in 1976, 1977 and 1978 from sampling stations in and around Sullom Voe are substantially free from pollution by crude oil; however, three of the samples collected during 1978 do show some signs of pollution. These data will act as a baseline for future studies to be carried out during the operation of the oil terminal.
Seals in Shetland waters
Authors: Anderson Sheila S. 
Published: March 2014

SynopsisThe distribution and status of grey and common seals around Shetland is reviewed. Recent surveys have produced an accurate picture of the location of breeding sites, grey seals being found at discrete localities mainly in the north and west of the islands and common seals being distributed more widely throughout the archipelago. The population of grey seals is estimated at 3,500 animals and is considered to be relatively constant. The reliability of boat surveys for estimating common seal populations is discussed. It is concluded that the population of Shetland has increased in numbers following protective legislation and it is suggested that there has also been a change in hauling out behaviour. The current population consists of at least 4000 individuals.Grey seals do not appear to have been affected by oil developments at Sullom Voe so far, but common seal numbers in the Sullom Voe area have not increased at the same rate as elsewhere in Shetland, and the number of pups present has declined. It is suggested that these changes may have arisen as a result of the development of the oil terminal. Study methods which would enable the nature and causes of these changes to be identified are proposed.
The soft shore environment of Sullom Voe and the north mainland of Shetland
Authors: Jones A. M. , Jones Y. M. 
Published: March 2014

SynopsisThe general character of soft shores in this region is considered briefly. Studies of several aspects of the biology at selected sites were instigated as part of a broader monitoring programme and the results of the baseline study are described in this paper. The structure and growth of populations of Cerastoderma edule (L.) and Macoma balthica (L.) (Mollusca: Lamellibranchiata) are described. Considerable differences in C. edule growth rates were found between sites, and recruitment and survival was sporadic at many sites. The value of C. edule populations in providing some degree of ‘retrospective monitoring’ is considered. C. edule populations were found to contain significant infections of the entocommensal nemertean Malacobdella grossa: this is a new host record for M. grossa. The distribution and abundance of the macrofauna on two sandy shores are discussed in relation to environmental conditions.
Measurement of the responses of mussels to environmental stress and pollution in Sullom Voe: a base-line study
Authors: Widdows J. , Bayne B. L. , Donkin P. , Livingstone D. R. , Lowe D. M. , Moore M. N. , Salkeld P. N. 
Published: March 2014

SynopsisThe base-line study consisted of three visits to Sullom Voe before the oil terminal became operational. General stress indices were used to measure the health and condition of four native and two transplanted populations of mussels (Mytilus edulis). A mobile laboratory was used to measure the physiological responses under ambient field conditions. These were then integrated into the stress indices, scope for growth and oxygen :nitrogen ratio. The general biochemical and cytological stress indices, namely taurine: glycine ratio, gametogenic development and latency of lysosomal β-hexosaminidase were also measured for each population. All these general stress indices indicated that the mussel populations were in a relatively healthy physiological condition. However, mussels from the Houb of Scatsta showed a transient stress response, probably caused by freshwater run-off from the surrounding peat beds.In addition to the general stress indices, specific cellular responses known to be induced by petroleum hydrocarbons were monitored. The activity of enzymes forming components of the mixed-function oxidase system (NADPH neotetrazolium reductase, G6PDH and NADP-ICDH, and aldrin epoxidation) were measured.The rationale for measuring these general and specific stress indices as part of a Sullom Voe environmental monitoring programme is discussed in the light of experiments with petroleum hydrocarbons in the laboratory and with reference to the future operation of the oil terminal.
Water relations and xylem anatomy of ferns
Authors: Gibson A. C. , Calkin H. W. , Raphael D. O. , Nobel P. S. 
Published: March 2014

SynopsisThe entire soil-plant-atmosphere continuum must be analysed to elucidate how xylem anatomy relates to water flow in plants. Measurements of water potential gradients and volume of water flow per unit time are needed to obtain values of hydraulic conductance per unit length. By comparing values of hydraulic conductance per unit length along the plant, the regions where xylem structure restricts water flow can be determined. Previous studies of fern water relations demonstrated that very large water potential gradients occurring in stipes of certain ferns were closely correlated with reduced conducting area of stipe xylem. A new study on Cyrtomium falcatum showed that the water potential gradient was relatively small and constant along the stipe and rachis; however, a much larger gradient occurred from the rachies into the pinnae. Hydraulic conductance per unit length varied with the leaf area to be supplied, leading to the fairly constant water potential gradient along the rachis.. The measured hydraulic conductance per unit length was only half the value predicted from the Hagen-Poiseuille equation. Although the Hagen-Poiseuille equation overestimated the measured value by a factor of 2, it did support the assumption that conduit number and lumen diameter are the principal determinants of water conductance in the xylem.
Distribution and ecology of early ferns
Authors: Scott Andrew C. , Galtier Jean 
Published: March 2014

SynopsisA review of current knowledge of the distribution of Palaeozoic ferns and fern-like plants is presented. Whilst numerous putative ferns occur in the Devonian, it is not until the Lower Carboniferous that ferns belonging to the Filicales appear. The Namurian represents a major gap in our knowledge. The ecology of late Palaeozoic ferns is reviewed. The association of early fern assemblages with volcanic terrains is considered particularly significant in the relationship between evolution and environment. Extinction of more specialised groups may have been caused by climatic changes.
The edible fiddlehead—Matteuccia struthiopteris (Ostrich fern)
Authors: von Aderkas P. 
Published: March 2014

SynopsisMatteuccia struthiopteris is distributed throughout most of the boreal region of the northern hemisphere. It has been variously recorded as a vermifuge and an ingredient in beer manufacture as well as a food. Young leaves, alternatively known as croziers or fiddleheads, are picked before they have unfurled and are boiled or steamed and served as a hot vegetable. The market, between Malecite indian and colonists, developed in the Fredericton area of New Brunswick 200 years ago, following a particularly severe winter. The newly arrived United Empire Loyalists, having emigrated from the United States, were so short of food that by the spring of 1784, they were reduced to eating any sort of provender nature could supply. Specific mention is made of fiddleheads, which became a traditional spring vegetable in New Brunswick. This market spread into Maine in the United States, particularly into those areas bordering the St John River. The present market is still predominantly in New Brunswick, where the wild harvest is between 150–200 t/yr, a yield which is approximately four times the harvest in neighbouring Maine. Food companies process about one third of the crop. In Maine, this is done by a single canning company in Wilton, whereas in New Brunswick, tinned fiddleheads have largely been superseded by the frozen product which is the monopoly of a company working in Florenceville. In addition, Canadian companies have recently sprung up which export the fresh spring vegetable in refrigerated lorries to larger centres west of the province. These companies account for less than a quarter of the harvest. The remainder is sold from either roadside stands, or to a wholesaler who distributes them to outlets in the region. The harvest is still predominantly done by natives. Much greater detail of both harvest, food preparation, and economic history is given by von Aderkas (1984). It has recently come to the author's attention that crowns of M. struthiopteris are sold also as a garden ornamental. Over 5000 plants/yr are sold by one Ontario distributor alone. Estimates from other nurseries in West Germany and the United States which do the same trade are presently unavailable.
Recent studies on the biology of bracken and the mode of action of herbicides used in its control
Authors: Kirkwood R. C. , Hinshalwood Anne 
Published: March 2014

SynopsisThe biology of bracken (Pteridium aquilinum L. Kuhn) is reviewed with particular reference to its importance as a troublesome weed of upland grasslands. The problem of control is discussed, particularly with regard to the role of the rhizome system and its associated buds. The modes of action of glyphosate and asulam are described with particular reference to their foliage-absorption, translocation, and the nature of activity in the buds, the ultimate target sites.
Recent studies on the potential for biological control of bracken using fungi
Authors: Burge M. N. , Irvine J. A. 
Published: March 2014

SynopsisCurl-tip disease of bracken (Pteridium aquilinum) is recorded from many sites in Great Britain. Evidence is presented which corroborates the findings of earlier workers that more than one organism is associated with the disease. Three fungi (Phoma aquilina, Ascochyta pteridis and Septoria sp.) are commonly isolated, even from the first visible necroses, suggesting that synergism may operate in pathogenesis. However, Phoma aquilina Sacc. and Penz. is more pathogenic than the others when used independently in inoculations via wounds into bracken raised in growth cabinets or the greenhouse. Field trials of a formulation of spores of P. aquilina, suspended in a dilute solution of the herbicide ioxynil with broth and glycerol, are reported. The potential of such a mycoherbicide for bracken control is considered.
Mobilisation of storage reserves during fern spore germination
Authors: DeMaggio A. E. , Stetler D. A. 
Published: March 2014

SynopsisWe have studied morphological and biochemical aspects of storage reserves and their degradation in fern spores during the germination process. The results presented here are concerned with the fate of lipid, protein and phytic acid. Depletion of lipid reserves and breakdown of lipid bodies was directly correlated with increased activity of glyoxylate cycle enzymes during early stages of germination. Degradation of protein reserves coincided with the depletion of salt soluble proteins (globulins) from the spores and was related to the time when high activity of aminopeptidase and carboxypeptidase was observed. Lipid and protein appeared to play an important role in germination. Phytic acid reserves were present in the spore and were hydrolysed by phytase after germination occurred. This storage material was implicated in growth of the prothallus.
Mobilisation of carbohydrates during germination of spores ofOnoclea sensibilis L.
Authors: Towill Leslie R. 
Published: March 2014

SynopsisA high percentage of germination ofOnoclea sensibilisL. spores is initiated by a low fluence of red light while imbibed but unirradiated spores exhibit a very low percentage of germination.Onocleaspores contain lipid, protein and sucrose reserves. Sucrose is degraded and starch is synthesised during germination while lipid reserves are mobilised during early gametophytic development. The amount of protein remains constant during both developmental stages. There is very little detectable mobilisation of any of the reserves in the imbibed but ungerminating spores maintained in the dark for up to 18 days. Sucrose degradation and starch synthesis are not interrelated because photoenhanced sucrose degradation can occur without starch synthesis and photoinduction of starch synthesis can occur without sucrose degradation. Evidence is presented to suggest that the mode of action of light in enhancing starch synthesis is to increase the availability of a starch precursor rather than the activities of starch synthesising enzymes. Sucrose may be mobilised after irradiation because it becomes accessible to the sucrose degrading enzymes which are in abundance in the spores.
Pteridophyte evolutionary biology: the electrophoretic approach
Authors: Haufler Christopher H. 
Published: March 2014

SynopsisWhile only in its infancy, the application of electrophoretic analysis in studying the evolutionary biology of pteridophytes is proving to be of considerable value. Since the technique identifies subtle differences in protein structure, it can generate an improved picture of the genetic composition of organisms. To date electrophoresis is (1) providing us with new information about the structure of the pteridophyte genome, (2) interfacing well with laboratory studies of breeding system mechanisms to indicate that some pteridophytes are predominantly outcrossing species, and (3) generating genome-specific markers for detecting hybrids and analysing patterns of evolution. Electrophoretic data suggest that species of Bommeria are very distinct from one another and may not be congeneric. Further, enzyme characters indicate that the sexual Bommeria species have maintained a mechanism to promote outcrossing in populations, in spite of the limitations that this breeding system places on colonising ability. In Cystopteris, electrophoretic markers are of value in deciphering species relationships and origins, especially among neopolyploid taxa. The indication in Cystopteris that extant diploids are outcrossing may help to explain the complex systematic patterns that currently exist within and among its taxa. Further investigations may demonstrate that similar mechanisms are prevalent among other systematically challenging ferns and fern allies.
Life-history studies of ferns: a consideration of perspective
Authors: Cousens Michael I. , Lacey Deborah Grimm , Kelly Eugene M. 
Published: March 2014

SynopsisAutecology of pteridophytes may be refined by defining the plant community and habitat, and phytogeographic occurrence, of the species studied. Work withBlechnum spicantin the Pacific Northwest, and withLorinserea areolatain the Southeastern U.S.A. has uncovered autecological differences for these species across habitats differing in overstory and hydrology. Natural history observations are necessary to suggest the most appropriate hypotheses to investigate objectively. A modification of Daubenmire's Canopy-Coverage method provides a grid across which many factors may be recorded or tested in repeatable objective manner. Such an analysis was used to test the association betweenL. areolatalife-history classes and hummocks in hardwood swamps. Contingency tables were used to disprove the null hypothesis thatL. areolatawas distributed randomly with regard to hummocks. Hummocks were thus ‘safe sites’ for the completion of the life-cycle ofL. areolata, and additional considerations of safe sites forLygodium japonicumandDryopteris ludovicianaare introduced. Analysis of biomass and coverage ofOnoclea sensibiliswhere it is very abundant suggests that it is highly susceptible to competition where it shares plots withL. areolata.The concept of the optimum habitat with regard to abundance of the taxon, frequency of the habitat-type, successful reproduction, and susceptibility to competition between similar life forms is discussed.
The arthropod cuticle and its inhabitants
Authors: Mellanby Kenneth 
Published: March 2014

SynopsisThe skin of arthropods is also the exoskeleton and as this gives them mechanical protection, they have comparatively few ectoparasites. Those which are present are removed during the periodic moulting of the skin. However, some organisms, particularly mites, have become adapted to living on the cuticle of arthropods.