University, Diss., 2007--Frankfurt (Main). / Zsfassung in engl. und dt. Sprache.

Growth. mortality. production. physiology and seasonal cycles of condition index and proximate biochemical composition of experimental populations of blue mussels (Mytilus edulis L.) were studied at different sites in Loch Etive and Loch Leven on the West coast of Scotland between May 1990 and September 1992. The main objective of the study was to evaluate current suspended mussel culture practices and to establish the basis for their possible integrated cultivation with salmon cage fanning. In addition. a preliminary investigation on employment of the . Charm IT' system as a rapid method for detecting residues of drugs used for treating cultured salmon in the tissues of mussels was carried out. There were some differences between sites in salinity, seston and particulate organic matter, but not in chlorophyll-a. Food availability (as particulate organic matter and chlorophyll-a) showed a clear seasonal cycle and in consequence growth of mussels were relatively rapid from late-spring until mid-autumn (g 6 months) and very slow or absent during the rest of the year. This period of rapid length and tissue growth coincided with relatively optimum environmental conditions and there were apparent positive relationships between monthly growth rates and temperature and chlorophyll-a values, indicating the limiting effect of these two primary factors on growth during autumn-winter and even in early spring. Almost all growth parameters examined were showed significant differences between the lochs. Growth performance of both native and transplanted mussels in Loch Leven was quite poor. Overall annual length increments were 25.1-25.9 mm at sites in Loch Etive and Dunstaffnage Bay, but 20.1-22.8 mm in Loch Leven. A crosstransplantation experiment showed that site rather than stock is the main reason for differences in growth parameters between Lochs Etive and Leven. These observed growth differences between sites and stocks were also confirmed by physiological measurements and estimated growth potential or scope for growth. Growth of mussels at salmon farms was faster than at neighbouring mussel farms during two annual experiments, but only meat weight at one salmon farm during experiment I, and length and live weight at the salmon farm in Loch Etive as well as all growth parameters at the salmon fann in Loch Leven during experiment II were significantly greater (}>sO.05). These differences were most likely a result of high particulate organic matter levels at salmon fanns. Similar to growth, biomass and production, the condition index and biochemical composition of mussels showed a clear seasonal cycle. Meat content, condition index and glycogen values were high during summer, started to decline in late autumn and reached minimum values in April before showing maximum increases in May. This reflects the typical storage and reproductive cycle of mussels in Northern Europe: accumulation of reserves during summer and their utilization during winter and early spring as energy resources for metabolism and reproduction. This cycle clearly showed that the main spawning of mussels on the West coast of Scotland occurred during March-May, and primary spat settlement from June to August. Heavy losses occurred from French socks, causing substantial amounts of eliminated biomass during experiment I, but when these fall outs were eliminated during experiment II by using lantern nets, it was clear that natural mortality rates were quite low and similar at all sites. Apart from growth characteristics and physiological responses, there were persistent morphological differences between the Loch Etive and Loch Leven populations. Cross-transplantation and physiological measurements after various acclimatization periods showed that, while morphological differences might be related to genetic origin, all other differences between the two popUlations are governed by environmental factors. The practical implications of these findings for developing suspended mussel culture on the West coast of Scotland and the possibility of a simple integrated salmon-mussel fanning system, which could be effective in controlling potential eutrophication from intensive salmon cage fanning and the removing large amounts of organic matter by mussels leading alterations in ecosystem, are discussed. A preliminary study with the Chann II Test has showed that the system is not so appropriate method as expected for screening mussel tissue sampled straight from the field, since mussel tissues require purification due to interference from bacteria or microbial detritus, before screening.

No description available.

Shellfish aquaculture is growing rapidly with the expanding human population, offering high-quality animal protein as well as economic benefits to producing areas. Cultivation relies on coastal and estuarine habitats, dynamic ecosystems where marine organisms including mussels are exposed to natural environmental variability, and which will be affected by climate change (e.g. ocean warming, acidification, desalination etc.). This thesis investigated the variability in blue mussel, Mytilus edulis, performances under suspended rope-culture in a stratified Scottish sea loch, Loch Leven. Environmental conditions were monitored over one year and at different culture depths and related to the mussel's product quality (meat yield, condition index), genetic composition (genotype, extent of hybridisation) and shell phenotype (shell strength and shape). Environmental conditions varied over time (seasonal cycles and short-term fluctuations) but also across depth, generating different microhabitats for mussels depending on their position on the rope. Conditions varied most at shallow culture depths, for salinity in particular, but presented warmer temperature and higher food availability compared to greater depths and promoted mussel growth and abundance. Meat yield and condition index followed a seasonal cycle, with maximum values in early summer and minimum values in winter, associated with environmental (nutritional) and reproductive cycles. The genetic composition and shell morphology of cultured mussels differed across depth. On average, every sixth mussel carried alleles of Mytilus trossulus, but the level of introgression was overall low. However, highly introgressed mussels (≥ 75 %) presented distinct shell morphology (significantly lower shell strength, elongated shell shape) and originated mainly from shallow culture depths. This phenotype distinguished them from their congeners and allowed for their identification based on shell characters. This thesis presents the variability in suspended mussel culture in a heterogeneous environment, highlighting the complex relationships between habitat conditions and the genetic and phenotypic make-up in naturally occurring mixed-species stocks. The knowledge gained offers guidance for the farm operators to optimise production (site selection, spat collection etc.) and provides better predictions for the industry on the possible effects associated with climate change on future mussel production.

There is little doubt that anthropogenic climate change will have long lasting, unavoidable, large scale and cross sector effects. Having a clear understanding of the scale and rate of projected future changes, and the potential impacts of those changes at multiple spatial and temporal scales, will be important to allow environmental managers the best chance of adapting to changing conditions. There are particular concerns about impacts on freshwater systems due to the coupling of direct impacts to both hydrology and ecology. Expected changes can be grouped into three functional categories: those affecting physico-chemical (broadly water quality), hydromorphological (physical structure and habitat) and biological elements of the lake system. The Lake-Landscape Context framework provides a way of approaching the sensitivity or resilience of an individual lake to change by exploring the complex and multi-layered relations between water, land and human activity. However, the exact combination of strategies and actions available to environmental managers is yet to be comprehensively documented beyond broad principles. To reach this goal, to manage our ecosystems in the most comprehensive and responsible way, we need to have a clear understanding of what and where that resource is, what the conservation priorities currently are and where threats to these priorities are likely to emerge. Therefore, the overall aim of this thesis was to develop adaptation strategies to minimise climate change impacts on the conservation interests of Scotland’s standing freshwater. This was approached through the adoption of the ESVRA conceptual framework, intended to assist policymakers and practitioners in adaptation planning. Practical actions can be guided by working through the framework’s four key stages: understanding exposure to the pressure (external drivers); considering the sensitivity and resilience of the system at multiple scales (internal functions); exploring areas of vulnerability (a measure of sensitivity plus exposure); and consideration of multiple possible responses across spatial and temporal scales. Chapter 2 explores the lake resource making use of the latest geospatial data and GIS techniques to investigate Scottish standing freshwaters in depth. 5,165 Scottish lakes exhibit an outstanding myriad of forms and sizes ranging across the country. This variety of form, density and distribution contribute to habitats of international importance for numerous species. Perhaps because of this diversity, no natural grouping of lakes were found based on simple hydromorphological categorisations. The use of landscape and wildness ‘scoring’ is a novel geographic approach, which may be an important factor in how landscapes are valued in the future. Chapter 3 investigates the direct exposure to global climate change facing Scotland. Projected changes to global climate were downscaled to illustrate impact on the UK and Scotland using both the UKCP09 and HadGEM2-ES climate models. Climate change by the 2050s will impact the UK in the range 1.1°C to 2.7°C with a clear South-East/North-West gradient. Precipitation too is projected to change in the UK in this time, with annual precipitation varying from -65 to +116 mm/yr. By incorporating the climate model data into a GIS it was possible to further interrogate the results for specific locations, with a detailed water balance model created for all 5165 lakes. This model suggests that during the summer months there will be sustained periods of water scarcity and deficit. Finally, in this chapter, a climate change spatial risk assessment was undertaken, identifying 200 lakes in the area of greatest projected change. Leading on from these findings, Chapter 4 explores the vulnerability of Scotland’s standing freshwaters. A vulnerability framework attempts to place resilience as a key part of the model, which has to date been missing from similar assessments. The expert weighted scoring mechanism highlights 851 of Scotland’s standing freshwaters, geographically spread across the country, as being highly vulnerable to projected climate changes. The results were mapped to show the vulnerability across Scotland and a display system for individual lakes proposed that allows a transparent and coherent structure that can shed light on distinct components of vulnerability, so that each can be evaluated individually, and in combination. Finally, in Chapter 5, a multipart online survey with key stakeholder experts actively involved in freshwater environmental management was produced to approach adaptation strategies and actions themselves. Over 80 adaptation actions specifically applicable to Scotland’s standing freshwaters were collated and grouped into 12 adaptation strategies. All 12 strategies were considered desirable with six strategies considered ‘Definitely feasible’, a further four considered ‘Likely feasible’. This provides a framework of potential actions that could help to reduce system sensitivity by increasing adaptive capacity or system resilience. In conclusion, while there are undoubtedly challenges ahead for Scotland’s standing freshwaters and for those who manage them, there is clear opportunity to make proactive and engaged decisions to minimise the impact of climate changes on the conservation interest of these important habitats.

The energetics of, the holotrich ciliate Colpidium campylum fed on the bacterium Moraxella sp. at 10°C, 15°C and 20°C were investigated. The parameter used for ascertaining growth. was the volume of protoplasm produced measured by means of a Coulter Counter with a mean cell volume converter attachment. Growth and consumption were measured in relation to food availability as indicated by the ratio of bacteria: protozoan. Mean cell volume variation and reproduction were also measured in relation to food availability and energy consumed. Protozoan and bacterial material were harvested by centrifugation and freeze-dried for dried weight determinations and calorimetry studies. The energy content of Colpidium and its food source was determined with a Phillipson microbomb calorimeter. Respiration was measured in a Warburg respirometer. Oxygen uptake in relation to population density and cell size was considered as well as the production of information concerning the heat lost during respiration for incorporation into energy budgets. Energy budgets of. two types were constructed: a 24-hour energy budget for an individual and the life-span or generation energy budget for an individual. Gross growth efficiencies, net growth efficiencies and assimilation efficiencies were considered in detail. In addition to laboratory work the vertical distribution of Ciliophora in the mud of Loch Leven, Kinross, Scotland, was also considered; three sites, two shallow and one deep, being sampled with a core sampler over a 12 month period.

Heidelberg, Univ., Diss., 2006.

Heidelberg, Univ., Diss., 2007.

The island of Rum in the Inner Hebrides, NW-Scotland, hosts a central volcanic complex that is part of the British-Irish Palaeogene Igneous Province situated in NE- Ireland and NW- Scotland. On Rum, rocks from several stages of Palaeogene magmatic activity have been exposed by millions of years of erosion. Rum is best known amongst geologists because of the famous layered ultrabasic intrusion that covers the SSE part of the island, which is amongst the world’s most studied non-active (fossil) volcanoes. The Long Loch Fault traverses Rum with an N-S direction and has been proposed to represent the feeder zone to the layered ultrabasic intrusion. The area close to the Long Loch Fault has been named the Central Intrusion, and was formed by interaction of the plutonic rocks with the Long Loch Fault. There are two end-member theories for the origin of the Central Intrusion: (i) formation by wholesale subsidence (graben formation) of layered ultrabasic units or (ii) by intrusion of new material in-between the Western and Eastern Layered Intrusions (brecciating and fracturing blocks of material from the layered suite) and so causing pulses of uplift and subsequent collapse. To test how the Long Loch Fault influenced magma emplacement on Rum, field work was conducted including structural mapping, and rock-sampling. The data collected in the field were processed by structural 3D modelling (Move Software suite) and complemented by petrography, FTIR, Electron Microprobe analysis and thermobarometry modelling. The results reveal that several fault splays cut the Central Intrusion, which furthermore provide evidence of a transtensional graben situated above the fault zone and into which the layered units collapsed. This collapse was associated with the intrusion of Ca-rich feldspathic peridotite at zones of weakness in the layered rocks (e.g. bedding planes, unit contacts and fractures), producing smaller fault blocks and acting as a lubricant in-between blocks. FTIR and barometry results show that the intruding feldspathic peridotite magma was water-rich and that the clinopyroxenes in the magma crystallised at approximately 15 km of depth. Consequently, a combination of both theories for the creation of the Central Intrusion appears most reasonable. The combination of data gathered allows to formulate a model in which the tectonic activity of the Long Loch fault repetitively opened and closed the magma conduit, causing pressure build-up in the underlying magma reservoir(s) when the conduit was shut. When the pressure was released, e.g. during fault movement, dense (phyric) and wet ultrabasic magma ascended rapidly and spread out into the shallow crustal magma chamber, thus supplying the growing ultrabasic pluton with pulses of magma from depth. / Ön Rum är en del av ö-gruppen Inre Hebridéerna i Nordvästra Skottland och består till stor del av magmatiska bergarter som härrör från en vulkan som var aktiv för cirka 60 miljoner år sedan. Vulkanen tillhör den Britiska Paleogena Magmatiska Provinsen och är skapad av mantelplymen som för nuvarande befinner sig under Island. Den nu eroderade vulkanen har en ikonisk status bland geologer världen över på grund av att den minerallagrade magmakammaren som utgör stora delar av ön, alltså själva hjärtat av vulkanen. Long Loch förkastingen delar Rum i två delar och har föreslagits vara huvudledaren av magma in i magmakammaren. Området på ön i anknytning till förkastningen har påverkats mycket av dess rörelser och har namngets den Centrala Intrusionen. Det finns två vitt skilda teorier om hur den Centrala Intrusionen har skapats: (i) den Centrala Intrusionen har skapats genom sättningar i magmakammaren och bildat en gravsänka, eller (ii) nytt material tränger i magmakammaren, vilket leder till upplyftning av magmakammar golvet som följs av sättning och bildar en gravsänka. I denna masteravhandling testades hypotesen ’Long Loch förkastningen var den primära magmaledaren till magmakammaren idag exponerad på Rum’ genom fältarbete, 3D modellering, petrografi, och geokemiska analyser (FTIR, Mikrosond och barometri). Resulatet visar att den Centrala Intrusionen genomskärs av flera förskastningsgrenar till Long Loch förkastningen vilka tillsammans formar ett tulpan mönster (en typ av gravsänka) som indikerar att en zon av flytande magma (magmaledare) låg under den Centrala Intrusionen när vulkanen var aktiv. Magman från zonen underlättade gravsänka bildandet genom att dela minerallagren i stora block och att intrudera mellan lager och fungera som glidmedel, vilket betyder att båda teorierna kan appliceras på bildandet av den Centrala intrusionen. FTIR och barometri analyserna visar att den intruderade magma var mycket vattenrik och och kom från en  magmakammere på 15 km djup. Long Loch förkastningens rörelser stängde och öppnade magmakanalen, vilket orsakade att kristallrik magma intruderade i pulser.

This thesis investigates whether lead mining can be detected using palaeoenvironmental data recovered from freshwater loch and marsh sediment. Using radiometric time-frames and geochernical analyses the environmental impact of 18th and 19th century mining on Islay, Inner Hebrides, Scotland, has been investigated. The model of known mining events thus produced has been used to assess previously unrecorded (early) lead mining activity. Previous mining in the area is suggested by 18th century accounts that record the presence of 1,000 "early" workings scattered over the north-east limestone region. While there is little to support the often repeated assertion that lead mining dates back to the Norse Period (circa lOll th centuries) it is clear that it may well have been an established industry prior to the time of the first historical records in the 16th century. In order to use a palaeoenvironmental approach to the question of mining history and its impact, the strategy has been to use integrated loch and catclunent units of study. The areas considered are; Loch Finlaggan, Loch Lossit, Loch Bharradail and a control site at Loch Leathann. Soil and sediment geochemical mapping has been used to assess the distribution of lead, zinc and copper within the catchments. Environmental pathways have been identified and influx of lead, zinc and copper to the loch sediment has been detennined through the analyses of cores from each loch basin. Archaeological fieldsurvey and the re-examination of the results from mineral prospecting data across the study region provides new evidence on the geographical extent and contaminatory effects of leadmining in this area. This study shows how the effect of lead mining can be identified in the palaeoenvironrnental record from circa 1367 AD onwards, so mining in Islay does indeed predate the earliest known archaeological and historical records.