The here presented PhD project explores the phenomenon of cereal cultivation during the Iron Age (c. 500 BC – AD 1100) in southern Scandinavia. The main body of the thesis consists of four articles. These were written with the aim to identify chronological, geographical, theoretical and methodological gaps in current research, to develop, apply and evaluate approaches to how new knowledge on Iron Age cereal cultivation can be attained, and to assess the interaction between archaeobotany and other specialisms currently used in settlement archaeology. The introduction section of the thesis also contains a historical overview of archaeobotanical research on cereal cultivation in southern Scandinavia. The first article is a compilation and summary of all available previously performed  archaeobotanical investigations in southern Sweden. This data is compared and discussed in relation to similar publications in Denmark and smaller scale compilations previously published in Sweden. The main result of the study is an updated and enhanced understanding of the main developments in the investigation area and a deepened knowledge of local development chronologies and trajectories in different parts of southern Sweden. The second article is a methodological presentation of a multiproxy analysis combining plant macrofossil analysis, phosphate analysis, magnetic susceptibility analysis and measurement of soil organic matter by loss on ignition. The applicability of the method for identification and delineation of space functions on southern Scandinavian Iron Age sites is discussed and illustrated by two case studies from the Danish site of Gedved Vest. Particular focus is placed on exploration of the use of the functional analysis for assessment of taphonomic and operational contexts of carbonised plant macrofossil assemblages. The third article aims at presenting an Iron Age cereal cultivation history for east-central Jutland, an area identified at the outset of the project as under-represented in archaeobotanical studies. The article combines data from depth analyses of material from the sites of Gedved Vest and Kristinebjerg Øst (analysed with the methods and theory presented in the second article) with a compilation of previously performed archaeobotanical analyses from east-central Jutland. The main results of the study are that developments in the study area appear to follow a chronology similar to that previously observed on Funen rather than the rest of the peninsula. Rye cultivation is furthermore discussed as more dynamic and flexible than previously presented in Scandinavian archaeobotanical literature. The fourth and final article leaves archaeobotany as the main topic. It focuses instead on evaluating, theorising and expanding the multiproxy method presented in the second article by a thorough comparison of the botanical, geochemical and geophysical methods to other techniques of functional analysis currently used in archaeology. These techniques include studies of artefact distributions, assessments of spatial relations between settlement features, and studies of the structural details of dwellings and other constructions. The main result is that there is a correspondence between the functional indications provided by botanical, geochemical and geophysical methods and techniques used in mainstream archaeology. The comparison furthermore shows that a combination of the two data sets allows for more highly resolved functional interpretations than if they are used separately. The main conclusion of the PhD thesis, based on the discussions in all four articles, is that archaeobotanical questions commonly necessitate the assessment of non-botanical archaeological material. The comparison of archaeobotanical data to other segments of the archaeological record does, however, enable the use of the former as an archaeological resource for addressing non-botanical questions. The increased understanding of (mainly settlement) site dynamics resulting from this integration of methods allows archaeobotanists to address increasingly complex botanical questions. Increased and more structured integration between archaeobotany and other specialisms operating within the framework of settlement archaeology is therefore argued to be the preferred approach to performing both high quality archaeobotany and settlement archaeology.

Die derzeitige Markt- und Preisentwicklung bei Schnittblumen gibt neue Impulse für eine Eigenproduktion. Besonders für Einzelhandelsgärtnereien bietet sich die energie- und investitionsarme Produktion im Freiland an. Innerhalb des Projektes "Sortimentssichtung und Erarbeitung von Anbauverfahren zur Erzeugung von Freilandschnittblumen und -schnittgrün von Stauden mit Absatzschwerpunkten vor und nach den Sommerferien" im Fachbereich Gartenbau Dresden-Pillnitz der LfL konnten Anbauhinweise und Sortimentsempfehlungen für den Freilandschnittanbau unter hiesigen Bedingungen erarbeitet werden. Die über einen längeren Zeitraum ermittelten Ertragskennzahlen am vollsonnigen Standort sowie die Daten zur Aufbereitung, zur Schnittblumenqualität und Vasenhaltbarkeit der Stauden ermöglichten die Zusammenstellung der in der Schriftenreihe dokumentierten umfang- und abwechslungsreichen Empfehlungssortimente. Sie erleichtern dem Erwerbsanbauer die Arten- und Sortenauswahl entsprechend der betriebsspezifischen Bedingungen, betriebswirtschaftlichen Überlegungen und des Kundenklientel. Im Mittelpunkt stehen dabei Stauden für die absatzstärkeren Zeiträume vor und nach den Sommerferien. Bei ausgewählten Arten und Sorten kann der Rückschnitt des Austriebes Mitte Mai zur Blühterminverspätung genutzt werden. Diesbezügliche Versuchsergebnisse sind den Sortimentsempfehlungen im Bericht angefügt. Innerhalb des Projektes wurden auch intensive Anbauversuche mit Montbretien und Clematis als Schnittblume erfolgreich durchgeführt. Als Ergebnis werden Sortimentsempfehlungen und Hinweise zum Kulturablauf und zur Produktion im Freiland gegeben. Wertvolle Anbauergebnisse bezüglich des Einsatzes von Xylit als Mulchstoff zur Reduzierung des Unkrautaufkommens runden die Projektergebnisse ab.

Berichte: Nährstoffgehalte der Fruchtarten im Ökologischen Landbau --- Wirkungsgrad organischer Düngemittel auf Ertrag und Qualität von Kartoffeln im Ökologischen Landbau --- Bekämpfung der Kraut- und Knollenfäule im Ökokartoffelanbau --- Anforderungen an die Humusbilanzierung in der Praxis des Ökologischen Landbaus --- Zur Intensität des Striegeleinsatzes gemessen an der Bodenbewegung unter Laborbedingungen und an einem Feldbestand von Wintergerste

Mit dem vorliegenden Forschungsprojekt wurde das Ziel verfolgt, für den Anbau von Substratkulturen unter den Bedingungen des Freistaates Sachsen wirtschaftlich optimierte Anbaufolgen und - empfehlungen zu erarbeiten. Im Vordergrund der Betrachtungen standen dabei die beiden wichtigsten Fruchtgemüsearten Gurke und Tomate.

Buddhist forms of “ethical advice”—instructions that address life’s problems and offer methods for alleviating them—are widespread in Buddhist literary history. This dissertation studies four such works, all written by the nineteenth-century Tibetan teacher Dza Patrul Rinpoche (Rdza dpal sprul O rgyan 'jigs med chos kyi dbang po, 1808-1877). I provide a rhetorical analysis of these compositions and endeavor to show how each aspires to reach outside of itself to act on its respective audience. The compositions do so, I argue, by deploying special literary devices that encourage their audiences to invest themselves, emotionally and imaginatively, in the practices of self-development that the works themselves advocate. The aim of the project is to use Patrul’s writing as a case study to suggest modes of analysis that can offer us insight into the ways in which specially designed modes of writing enable moral self-cultivation. The dissertation specifically addresses the relationship between the recurring themes of singularity, performativity and reflexivity as they appear in Patrul’s advice writings. I argue that these compositions employ discursive devices that play on their audience’s feelings and expectations, aspiring to generate affective responses that range from utter hopelessness to profound relief. They employ expositional strategies designed to compel their audiences to imagine familiar practices anew. Finally, their performative character calls attention to the status of Patrul, the model author, as a singularly capable and skillful teacher. The reflexive nature of Patrul’s works thereby serves to provoke the implied audience’s imagination about “Patrul” the heroically talented teacher. These self-reflexive writings also act as devices for Patrul’s own self-transformation. They are sites of imagination, opportunities for Patrul to enact a self-creation via the medium of advice writing. Patrul’s compositions not only aspire to work on their audience. They, in and of themselves, constitute transformative work for Patrul.

Scenedesmus obliquus is a freshwater microalga which has high lipid content and biomass productivity. It is regarded as a promising species for production of biodiesel and other valuable organic compounds. Given the high cost of using potable water and commercial fertilizers, the use of municipal wastewater as algal growth medium is attractive in view of its constituent organic carbon and inorganic nutrients, including nitrogen and phosphorus. Investigating the mixotrophic cultivation of S. obliquus in an imitation municipal wastewater, the results of this study showed that: (1) The unmodified imitation wastewater by itself as expected yielded poor S. obliquus growth owing to its pH significantly decreasing to 3.5 as caused by the presence of Ammonium Chloride in the wastewater, inhibiting cell growth; (2) Adding either Acetic Acid or Sodium Acetate to the wastewater medium maintained its pH at 6.5 to 7.0, and its algae biomass on day 6 increased significantly by 212% and 194%, respectively; (3) Adding either Acetic Acid or Sodium Acetate to the wastewater medium maintained its pH at 6.5 to 7.0, and its algae biomass during exponential phase (day 4) significantly exceeded that in the MF control by 220.6% and 165.8%, respectively, while its algae biomass during saturation (day 6) significantly exceeded that in the MF control by 60.8% and 51.5%, respectively; and (4) Addition of NaNO₃ to the wastewater to match the level of N in the MF medium improved the algae biomass by 10%. This study developed ways for how the successful mixotrophic cultivation of S. obliquus in municipal wastewater could be achieved.

This research investigated the influence of television viewing on the social identity management or coping strategies endorsed by women. Three studies (N = 536) tested predictions formulated under the aegis of cultivation theory and social identity theory. Cultivation theory suggests that exposure to low-status mediated portrayals of female characters may lead to the internalization of low status in female heavy television viewers, possibly resulting in a negative ingroup or social identity. According to social identity theory, members of low-status groups may cope with negative social identity by adopting any of three identity management strategies: individual mobility (disassociating oneself from the ingroup), social creativity (changing the dimension of comparison with a high-status group or changing the comparison group altogether), and social competition (actively pursuing legal and/or civil means in order to obtain a higher status for the ingroup). By integrating the identity management strategies as outcome variables in a cultivation-led framework, the main predictions of this research were that television viewing would be directly related to strategies of mobility and creativity and inversely related to social competition. A model of television viewing's indirect effects on identity management via its influences on the sociostructural constructs (permeability, stability, and legitimacy) was also tested in this research. Finally, this research examined other theoretically important variables that were predicted to impact television's cultivation effects. These were (i) gender role attitudes, (ii) perceived ingroup vitality, (iii) ingroup identification, (iv) perceived ingroup efficacy, and (v) perceived realism of television programming. The findings from these three studies indicate that television viewing has both direct and indirect influences on identity management in women. Specifically, television viewing was significantly and positively related to individual mobility and significantly and inversely related to attitudes of social competition. As television viewing was not related to any of the sociostructural variables, the preliminary model testing television viewing's indirect effects on identity management was not successful. However, a revised model incorporating perceived status of women, and perceived ingroup vitality, was more successful and consistently explained the data across the three studies. In non-traditional women, television viewing and gender role attitudes interacted to predict heightened mobility and creativity scores, and dampened attitudes of social competition. Similar but weaker effects were observed for more traditional women. Perceived ingroup vitality, ingroup identification, perceived ingroup efficacy, and perceived realism of television did not moderate the relationship between television viewing and identity management. The findings from the dissertation expand and add to the growing body of work integrating media effects and intergroup communication theories. Specifically, it extends the work focusing on media's influences on low-status group members' identity cognitions.

Grasping the wooden handle of a dozukime saw with both hands, I make a rip-cut into a block of eastern white pine, leaving behind a 1/64-inch wide kerf. I am cutting a dovetail: a wood joint developed over five-thousand years ago by the hands of our ancestors. Even now, a well-fitted dovetail joint remains one of the strongest, most elegant ways to join wood. I knew nothing about traditional woodworking when I first picked up a hand-plane, but I was soon inspired by the richness of the craft: the quality of a hand-planed finish, the spirit of craftsmanship, and the nature of material. I was amazed by the wealth of knowledge embodied in craftwork. The tools and materials I encountered spoke to me; I learned to care for them and for my work. How would the things I make endure through time? How would the things I make affect others? In an era where materialism has come to represent a spiritless relationship to the things around us, traditions of craft can teach us how to imbue the human spirit in our work. After making a harvest table, four chairs, ninety-four earthenware pots, and a lamp, I reflect on the act of making as a means of discovery. Making affects our thinking and our approach to material and environment. Making can help us develop a craftsman???s capacity to listen, a great respect for material, and a desire to make better objects for posterity. Making is learning.

In mehrjährigen Stoppelbearbeitungsversuchen mit Grubbern, Scheiben- und Kreiseleggen sollten Einsatzhinweise zur Verringerung der Bodenerosion bei pflugloser Bodenbearbeitung für verschiedene Maschinentypen entwickelt werden. Dazu wurde vor allem die Bodenbedeckung mit Mulchmaterial als wichtiger Indikator für den Schutzgrad beobachtet. Zusätzlich wurden Daten zur Stroheinarbeitung in den Boden sowie zur Ausprägung der Bodenoberflächen und Bearbeitungssohlen ermittelt und der Zugleistungsbedarf für die Geräte gemessen. Im Ergebnis konnte der Bodenbedeckungsgrad nur wenig durch Veränderung der Einsatzbedingungen der Stoppelbearbeitungsmaschinen beeinflusst werden. In erosionsgefährdeten Gebieten kommt daher dem Zwischenfruchtanbau und Bodenbearbeitungsverfahren, die einen hohen Bodenbedeckungsgrad gewährleisten (Streifenbodenbearbeitung, Direktsaat), eine entscheidende Rolle zu. Der Bericht enthält die vollständigen Ergebnisse der Untersuchung.

Renewable energy sources such as biomass are becoming more and more important as alternative to fossil fuels. One of the most exciting new sources of biomass is microalgae. The Hartbeespoort Dam, located 37 km west of South Africa’s capital Pretoria, has one of the dense populations of microalgae in the world, and is one of the largest reservoirs of micro-algal biomass in South Africa. The dam has great potential for micro-algal biomass production and beneficiation due to its high nutrient loading, stable climatic conditions, size and close proximity to major urban and industrial centres. There are five major steps in the production of biodiesel from micro-algal biomass-derived oil: the first two steps involve the cultivation and harvesting of micro-algal biomass; which is followed by the extraction of oils from the micro-algal biomass; then the conversion of these oils via the chemical reaction transesterification into biodiesel; and the last step is the separation and purification of the produced biodiesel. The first two steps are the most inefficient and costly steps in the whole biomass-to-liquids (BTL) value chain. Cultivation costs may contribute between 20–40% of the total cost of micro-algal BTL production (Comprehensive Oilgae Report, 2010), while harvesting costs may contribute between 20–30% of the total cost of BTL production (Verma et al., 2010). Any process that could optimize these two steps would bring a biomass-to-liquids process closer to successful commercialization. The aim of this work was to study the cultivation and harvesting of micro-algal biomass from the Hartbeespoort Dam for the production of biodiesel. In order to do this a literature study was done and screening experiments were performed to determine the technical and economical feasibility of cultivation and harvesting methods in the context of a new integrated biomass-to-liquids biodiesel process, whose feasibility was also studied. The literature study revealed that the cyanobacterium Microcystis aeruginosa is the dominant micro-organism species in the Hartbeespoort Dam. The study also revealed factors that promote the growth of this species for possible incorporation into existing and new cultivation methods. These factors include stable climatic conditions, with high water temperatures around 25oC for optimal Microcystis growth; high nutrient loadings, with high phosphorus (e.g. PO43-) and nitrogen concentrations (e.g. NO3-); stagnant hydrodynamic conditions, with low wind velocities and enclosed bays, which promote the proliferation of Microcystis populations; and substrates like sediment, rocks and debris which provide safe protective environments for Microcystis inoculums. The seven screening studies consisted of three cultivation experiments, three harvesting experiments and one experiment to determine the combustion properties of micro-algal biomass. The three cultivation experiments were conducted in three consecutively scaled-up laboratory systems, which consisted of one, five and 135-litre bioreactors. The highest productivity achieved was over a period of six weeks in the 5-litre Erlenmeyer bioreactors with 0.0862 g/L/d at an average bioreactor day-time temperature of 26.0oC and an aeration rate of 1.5 L/min. The three cultivation experiments revealed that closed-cultivation systems would not be feasible as the highest biomass concentrations achieved under laboratory conditions were too low. Open-cultivation systems are only feasible if the infrastructure already exists, like in the case of the Hartbeespoort Dam. It is recommended that designers of new micro-algal BTL biodiesel processes first try to capitalize on existing cultivation infrastructure, like dams, by connecting their processes to them. This will reduce the capital and operating costs of a BTL process significantly. Three harvesting experiments studied the technical feasibility and determined design parameters for three promising, unconventional harvesting methods. The first experiment studied the separation of Hartbeespoort Dam micro-algal biomass from its aqueous phase, due to its natural buoyancy. Results obtained suggest that an optimum residence time of 3.5 hours in separation vessels would be sufficient to concentrate micro-algal biomass from 1.5 to 3% TSS. The second experiment studied the aerial harvesting yield of drying micro-algal biomass (3% TSS) on a patch of building sand in the sun for 24 hours. An average aerial harvesting yield of 157.6 g/m2/d of dry weight micro-algal biomass from the Hartbeespoort Dam was achieved. The third experiment studied the gravity settling harvesting yield of cultivated Hartbeespoort Dam-sourced microalgae as it settles to the bottom of the bioreactor after air agitation is suspended. Over 90% of the micro-algal biomass settled to the bottom quarter of the bioreactor after one day. Cultivated micro-algal biomass sourced from the Hartbeespoort Dam, can easily be harvested by allowing it to settle with gravity when aeration is stopped. Results showed that gravity settling equipment, with residence times of 24 hours, should be sufficient to accumulate over 90% of cultivated micro-algal biomass in the bottom quarter of a separation vessel. Using this method for primary separation could reduce the total cost of harvesting equipment dramatically, with minimal energy input. All three harvesting methods, which utilize the natural buoyancy of Hartbeespoort Dam microalgae, gravity settling, and a combination of sand filtration and solar drying, to concentrate, dewater and dry the micro-algal biomass, were found to be feasible and were incorporated into new integrated BTL biodiesel process. The harvesting processes were incorporated and designed to deliver the most micro-algal biomass feedstock, with the least amount of equipment and energy use. All the available renewable power sources from the Hartbeespoort Dam system, which included wind, hydro, solar and biomass power, were utilized and optimized to deliver minimum power loss, and increase power output. Wind power is utilized indirectly, as prevailing south-easterly winds concentrate micro-algal biomass feedstock against the dam wall of the Hartbeespoort Dam. The hydraulic head of 583 kPa of the 59.4 meter high dam wall is utilized to filter and transport biomass to the new integrated BTL facility, which is located down-stream of the dam. Solar power is used to dry the microalgae, which in turn is combusted in a furnace to release its 18,715 kW of biochemical power, which is used for heating in the power-intensive extraction unit of the processing facility. Most of the processes in literature that cover the production of biodiesel from micro-algal biomass are not thermodynamically viable, because they consume more power than what they produce. The new process sets a benchmark for other related ones with regards to its net power efficiency. The new process is thermodynamically efficient, exporting 20 times more power than it imports, with a net power output of 5,483 kilowatts. The design of a new integrated BTL process consisted of screening the most suitable methods for harvesting micro-algal biomass from the Hartbeespoort Dam and combining the obtained design parameters from these harvesting experiments with current knowledge on extraction of oils from microalgae and production of biodiesel from these oils into an overall conceptual process. Three promising, unconventional harvesting methods from Brink and Marx (2011), a micro-algal oil extraction process from Barnard (2009), and a process from Miao and Wu (2005) to produce biodiesel through the acid-catalyzed transesterification of micro-algal oil, were combined into an integrated BTL process. The new integrated biomass-to-liquids (BTL) process was developed to produce 2.6 million litres of biodiesel per year from harvested micro-algal biomass from the Hartbeespoort Dam. This is enough to supply 51,817 medium-sized automobiles per year or 142 automobiles per day of environmentally friendly fuel. The new BTL facility consists of three sections: a cultivation section where microalgae grow in the 20 km2 Hartbeespoort Dam to a concentration of 160 g/m2 during the six warmest months of the year; a harvesting section where excess water is removed from the micro-algal biomass; a reaction section where fatty acid oils are extracted from the microalgae and converted to biodiesel, and dry biomass rests are combusted to supply heat for the extraction and biodiesel units of the reaction section. The cultivation section consist of the existing Hartbeespoort Dam, which make up the cultivation unit; the harvesting section is divided into a collection unit (dam wall part of the Hartbeespoort Dam), a concentration unit, a filtration unit, and a drying unit; the reaction section consists of an oil extraction unit, a combustion unit, and a biodiesel unit. At a capital cost of R71.62 million (R1.11/L) (±30%), the new proposed BTL facility will turn 933,525 tons of raw biomass (1.5% TSS) into 2,590,856 litres of high quality biodiesel per year, at an annual operating cost of R11.09 million (R4.28/L at 0% producer inflation), to generate R25.91 million (R10.00/L) per year of revenue. At the current diesel price of R10.00/L, the new integrated BTL process is economically feasible with net present values (NPV) of R368 million (R5.68/L) and R29.30 million (R0.45/L) at discount rates of 0% and 10%, respectively. The break-even biodiesel prices are R5.34/L and R7.92/L, for a zero NPV at 0% and 10% discount rates, respectively. The cultivation of micro-algal biomass from the Hartbeespoort Dam is only economical if the growth is allowed to occur naturally in the dam without any additional cultivation equipment. The cultivation of micro-algal biomass in either an open or a closed-cultivation system will not be feasible as the high cost of cultivation will negate the value of biodiesel derived from the cultivated biomass. The utilization of the three promising harvesting methods described in this work is one of the main drivers for making this process economically feasible. At a capital cost of R13.49 million (R37.77/ton of dry weight micro-algal biomass) and a operating cost of R2.00 million per year (R210.63/ton of dry weight micro-algal biomass) for harvesting micro-algal biomass from the Hartbeespoort Dam, harvesting costs account for only 19% and 18% of the overall capital and operating costs of the new process, respectively. This is less than harvesting costs for other comparative processes world-wide, which contribute between 20 and 30% of the overall cost of biomass-to-liquids production. At current fuel prices, the cultivation of micro-algal biomass from and next to the Hartbeespoort Dam is not economical, but the unconventional harvesting methods presented in this thesis are feasible, if incorporated into the new integrated biomass-to-liquids biodiesel process set out in this work. / Thesis (Ph.D. (Chemical Engineering))--North-West University, Potchefstroom Campus, 2011.