In 1942 an experiment was started in order to test the possibility of increasing the fertility of a small sea-loch by the addition of nitrate and phosphate fertilizers, with the view of improving the growth rate and yield of fish. It was based on the well-established fact that the phytoplankton organisms are the main producers of organic matter and therefore represent the main source of food supply in the sea, and that nitrogen and phosphorus compounds are among the important factors controlling and limiting plankton production. It was thought that the addition of readily available plant nutrients would result in an increase of plankton production and thus of the food supply of the bottom-living animals which are fed upon by fish. An increase of the bottom fauna might then result in an improved growth rate of the fish population. Normally most marine fish require about four years to reach marketable size, and the object of our experiment was to find out whether the addition of fertilizers would lead to a shortening of that period and to an improvement of the yield in fish per unit area.

It is an impossible task to identify a precise point in time which marks the start of an important departure in scientific thought. Every such development has its antecedents in earlier observations, ideas and interpretations. This applies as much to ecology as to any other branch of knowledge, if not more so since ecology at least in part is a synthetic discipline, depending for its progress on advances in other relevant aspects of biological and environmental science. Ecology is, perhaps, more an approach to biological enquiry than a ‘subject’ with clearly circumscribed information content and terms of reference. It is, however, a distinctive approach in that it concerns the interactions between organisms and the environments within which they habitually dwell, and their interactions among themselves in populations and communities.

Organisms and sea floor sediments respond to a number of physical and physico-chemical factors, the understanding of which permits identification of areas with typical and potentially aberrant habitats and deposits. After a resumé of the bathymetry of Scottish water tides, tidal current and residual currents stemming from the circulation in the North Atlantic are examined. The salinity and temperature interrelationships in many areas are summarised in open shelf waters, sea lochs and estuaries. Sea floor sediments commonly reflect reworking of glacial deposits coupled with varying indigenous populations of organisms which contribute skeletal debris to the particulate assemblages characterising the bed.

A lack of modern river-borne sediment and a steady supply of marine materials have led to the hypothesis that the upper Tay estuary is undergoing an erosive phase counterbalanced by a headward moving sheet of largely marine-derived sand presently occupying the upper-middle estuary. This primal division (based on sediment budget criteria) is also reflected in the bathymetry, distribution of sediment types, and sedimentary structures. The situation of two contrasting ‘phase zones’ juxtaposed within a relatively small area is ideal for an empirical and indirect analysis of the response of a wide variety of sediment types to the gross physical processes acting on them. The analysis takes the form of standard grain-size characterisations using conventional sedimentary statistics, supplemented by adaptations of C-M and QDa-Md diagrams transformed for display on distribution maps.

Early investigations into the effects of pressure on marine invertebrates were concerned mainly with determining limits of tolerance to extreme pressures, but within the last 25 years it has gradually emerged that many invertebrates are sensitive to quite small changes in pressure, often less than one atmosphere (1000 mb). The responses of most planktonic animals appear to be of a depth regulatory nature but certain littoral organisms show rhythmic changes in activity in response to cyclical pressure changes of tidal amplitude and frequency. The ecological role of such responses is considered.

The parameters of the pressure sense are known only from behavioural studies and offer little information concerning the process of reception. A possible mechanism of transduction based on the compression of a surface film of gas is described.

The microbial populations on cereal straw at harvest are characteristic of the phylloplane. Incorporation of straw into soil represents an enrichment disturbance and results in a rapid stimulation of soil microbial activity. The dominant fungal colonists of the straw in soil were found to vary with soil water potential over a twenty-eight week period of incorporation. The dominant fungal genera were Penicillium and Mucor, followed by Gliocladium, Fusarium and Trichoderma. Basidiomycetes were only isolated from straw in a wet (−0.1 MPa) soil. Prior inoculation of straw with Gliocladium roseum (Link) Banier resulted in changes in the dominance of these fungi, particularly in a dry soil. In vitro data on spore germination, germ tube extension and growth of these soil fungi on agar media were not correlated with those on unsterile straw leaf sheaths or sterile straw segments.

The agarics fruiting in natural and anthropogenic disturbed habitats are considered. The early colonists of such environments are species either able to utilise ephemeral resources or able to move nutrients quickly from one source to another. A suite of micro-characters uniting the species concerned is given. Attention is drawn to those agarics recorded from burns in various parts of the world, and from arctic-alpine areas. The concept of a geomorphological escalator is explored.

The degree of active interest shown by Governments in new sciences or research disciplines is very often related to the extent that these are reckoned to be of economic significance to society or the State. In Norway, nature research obtained ofiicial support, inter alia, on account of the fisheries and the problems with which the fishing industry was faced. Interest in the natural history of deep-sea animals and the development of marine biology as a research discipline goes back not least to these sources. The fluctuations in the major coastal fisheries have played an important part in directing attention to the actual natural resources and to research into the natural factors conditioning development of fishing as a means of livelihood. The fact that it was based for so long and to such a large extent on coastal fishing made this livelihood particularly susceptible to changes in the natural resources. Norwegian fishermen based their activities on the spawning and feeding migrations of the fish to the coastal waters and the fiords.Because of this they lacked the necessary stimulus to develop offshore oceanic fishing in the way some of the other fishing nations did. Coastal fishing demanded relatively modest investment in boats and equipment. The numbers taking part were so great and the individual yield at the same time so small that there was little opportunity to accumulate the sizable surplus which might have promoted development in a capitalist manner based on large, ocean-going vessels. For example, as long as the summer herring or fat herring could be caught in the fiords it was not necessary to go out to sea to meet the herring shoals. The fishermen had neither the capital nor the experience to adapt their operations to oceanic fishing if the herring failed to appear. The fisheries were based to such an excessive degree on the great influxes to the coast of cod and herring thatwhen these failed to materialise, as happened from time to time, the effects were correspondingly serious. It was therefore not surprising that interest in the natural resources appeared early in Norway and that the country in many respects came to be a pioneer in marine biological research.

The physiology of three nitrate respiring bacteria, identified as Klebsiella strain K312, Pseudomonas strain P388 and Vibrio strain V25, obtained from Kingoodie Bay sediments in the River Tay by enrichment techniques, have been studied in continuous culture. In glycerol limited anaerobic cultures Klebsiella K312 produced NO2 as the primary product of nitrate reduction whereas under N-limited conditions NH4+ was excreted into the culture medium. Nitrate reduction in this organism was accompanied by the synthesis of a paniculate nitrate reductase (NR) whilst under N-limitation a soluble nitrite reductase (NiR) was also produced. In contrast, Pseudomonas P388 dissimilates NO3 directly to gaseous products under anaerobic conditions and was associated with the synthesis of a particulate NR and under N-limited conditions a NiR. Nitrite never accumulated as an intermediate. Vibrio V25 would only reduce NO3 as far as NO2 and was therefore restricted in its use of NO3 under anaerobic conditions. Klebsiella K312 was the most versatile of the three organisms studied and since Klebsiella spp were found in significant numbers in the Kingoodie sediments they may account in part for the high interstitial NH4+ levels found there.

From a faunistic survey in Scottish waters, concentrated mainly in the sea lochs of the north-west coast and in the deep water in the North Sea off the east coast, thirty-two species of polychætes are listed which have not previously been recorded from these areas. Seven of the species are new records for British coastal waters or for the North Sea.

The major rock types which comprise the Outer Hebrides are described and the geological history of the region is discussed. The control exercised by the variations in structure and lithology on the topography is illustrated and an assessment made of the economic potential of the various rock units.

The world's oceans continue to play a vital part in man's history on this planet. There is no doubt that in the long process of evolution man's early ancestors left the sea for the land. There is evidence too that some of these having progressed to the mammal stage returned to the sea to produce the dolphins, whales and seals. Some biologists believe that man's predecessors did likewise. Being driven by a shortage of food, they ventured into the shallow coastal waters to collect shell fish and other accessible sea food. During this period they lost much of their fur and learnt to swim. Unlike the aquatic mammals, they remained land animals. It must also be assumed that primitive man developed a great fear of the sea which remained with him even after he had developed the use of boats. Its storms, its vastness, its tides and its currents must have filled him with awe. Even in modern times seafaring occupations are considered hazardous pursuits and drowning as a cause of death is greatly dreaded. In the simple man's mind the dark ocean depths with unpredictable moods of violence create a sense of fear subconsciously supported by the fact that the newly born human being emerges from the dark and watery confines of the womb wherein it has, in its development, recapitulated the pattern of man's evolution. To return to explore the sea would be to retreat into the timeless past. It is not surprising, therefore, that extensive exploration of the sea and sea bed has lagged behind the extension of man's activity over the great land masses, the conquest of the highest mountains, the development of flight and in later years the conquest of space.

During periods of sustained moderate river discharge and quiescent marine conditions little external suspended sediment enters the estuarine circulation of the Tay. That material which is in suspension is largely derived from the estuary margins where tidal currents superimposed by wind-induced waves are competent to resuspend fine material from the surface of the ‘mud’ flats and erode bedded silts from the incised banks of minor channels and runnels draining them. The quantities of this sediment entering the system are largely determined by tidal state and amplitude, as well as wind velocity.

On spring tides the flats are entirely covered at high water, and dry out completely at low water. The volume of water and its areal coverage at high tide ensures that, during the ebb, water charged with high concentrations of suspended sediment is directed from the fiats into the surface and middepth waters of the main channel. This process acting along the 20 km length of the channel flanking the ‘mud’ flats, combined with the low tide ‘ponding effect’ caused by the tide flooding from the sea while the upper estuarine water is still ebbing, results in the cumulative formation of a zone of high suspended sediment concentrations (turbidity maximum). As the flood tide becomes fully established the zone is diluted and dispersed. During neap tides the same processes operate, but because a smaller area of the flats is covered at high water and uncovered at low water, and because neap tidal current speeds are lower than those for spring tides, two proportionally weaker zones are recognised.

Following periods of sustained moderate river discharge, quiet sea conditions and calm weather, suspended sediment concentrations in the Tay are negligible irrespective of tidal state or amplitude.

Fishing with both a shore seine net and a small otter trawl in the summer of 1943 and the spring of 1944 showed that the native fish population was very sparse. No estimate of the size of fish population was attempted in 1944. Estimates undertaken in 1945 and 1946 will be discussed later (p. 120). Fishing in the period June to September 1945 produced small numbers of fish tabulated on p. 110, and some plaice and flounders which will be dealt with separately.

In addition there were fairly large numbers of gobies, sticklebacks, pipe fish and sand eels which, however, were not usually recorded in our catches. Shoals of young herring appeared only in the summer and autumn of 1945.

The variability of the pubescent birch and the probable existence of hybrids between it and two other birches make it a difficult species to classify at an infraspecific level. To some extent, the variation is geographical and to cover its distribution, three subspecies are proposed by the authors of Flora Europaea, sspp. pubescens, carpatica and tortuosa. Two subspecies are recognized in Britain, namely ssp. pubescens and ssp. odorata, but some confusion has arisen through the undetermined relationships between sspp. odorata, carpatica and tortuosa. The rejection of ssp. odorata is proposed as its application, in this case, differs from that intended by J. M. Bechstein, the original authority. An examination of the literature indicates that ssp. tortuosa and ssp. carpatica are probably indistinguishable (a conclusion supported by multivariate analysis) and that the epithet tortuosa can be applied to both taxa. The pubescent birch in the Scottish Highlands may be referred to ssp. tortuosa and, in addition, the high frequency of small-leafed individuals in some populations in the northwest and at higher altitudes, justifies the further distinction of var. microphylla Hartman.

The concept of heritability is discussed in relation to the climatic changes which may affect the variations of age at sexual maturity in the fowl, and it is suggested that genetic and environmental variance, as expressed in the customary statistical formulation, may be largely synonymous terms.

Four groups of Brown Leghorn pullets are compared, one subject to no artificial lighting and the sub-optimal conditions of war years, a second to restricted lighting, and a third and fourth to 14-hour day length. The formal estimates of genetic and environmental variance were respectively 910 and 978, 594 and 546, 188 and 295, and 56 and 135. Further reduction of variability is apparent on subdivision into early and late hatches, heritability being apparently zero in the first case but maintained at an average level in the second.

Changes in variability substantiate the presence of genotype-environment interactions as previously reported, and similar conclusions follow from heterogeneity of regressions of age at maturity on date of hatch.