Structural and agentic analysis of supply-chains: a social network analysis approach

This research adds to a body of work exploring the role of Social Network Analysis (SNA) in the study of both relational and structural characteristics of supply chain networks. Two contrasting network cases (food enterprises and digital-based enterprises) are chosen in order to elicit structural differences in business networks subject to divergences in local embeddedness and the relative materiality of the goods and services produced. Our analysis and findings draw out differences in network structure as evidenced by metrics of network centralization and cohesion, the presence of components and other sub-groupings, and the position of central actors. We relate these structural features both to the nature of the networks and to the (qualitative) experiences of the actors themselves. We find, in particular, the role of customers as co-creators of knowledge (for the Food network), the central role of infrastructure and services (for the Digital network), the importance of ICT as a source of codified knowledge inputs, along with the continuing importance of geographical proximity for the development and transfer of tacit knowledge and for incremental learning.

Chemistry and stable isotope record of sediment core GeoB4905-4

Evidence of rapid climatic oscillations like those observed in the Greenland ice cores and sediments from high latitudes of the northern Atlantic have been recognized in the pulses of terrigenous material to continental margin sediments off Cameroon. Fe/Ca ratios used as a parameter to quantify the relative proportions of terrigenous fluxes versus marine carbonate monitor the variability of the west African monsoon. They reveal the history of abrupt changes in precipitation over western and central Africa during the past 52 kyr. These rapid changes are particularly pronounced during the last glacial period and occur at timescales of a few thousand years. Stable oxygen isotope (delta18O) records of Globigerinoides ruber (pink) show high negative values reflecting periods of high monsoon precipitation. The Fe/Ca pattern is very similar to the Dansgaard-Oeschger cycles from the Greenland ice cores. The good correspondence between the warm interstadials of the Dansgaard-Oeschger cycles from the GISP2 ice core records and the high pulses of Fe/Ca sedimentation in our core suggest a strong teleconnection between the low-latitude African climate and the high-latitude northern hemisphere climate oscillations during the last glacial. This climatic link is probably vested in the west African monsoonal fluctuation that alters tropical sea surface temperatures, thermohaline circulations and in turn net export of heat from the south to the north Atlantic, coupled with the variability of the low-latitude southeast trade winds.

Degradation rates and productivity signals of organic-walled dinoflagellate cyst species in surface sediment samples

To understand the role of the ocean within the global carbon cycle, detailed information is required on key-processes within the marine carbon cycle; bio-production in the upper ocean, export of the produced material to the deep ocean and the storage of carbon in oceanic sediments. Quantification of these processes requires the separation of signals of net primary production and the rate of organic matter decay as reflected in fossil sediments. This study examines the large differences in degradation rates of organic-walled dinoflagellate cyst species to separate these degradation and productivity signals. For this, accumulation rates of cyst species known to be resistant (R-cysts) or sensitive (S-cysts) to aerobic degradation of 62 sites are compared to mean annual chlorophyll-a, sea-surface temperature, sea-surface salinity, nitrate and phosphate concentrations of the upper waters and deep-water oxygen concentrations. Furthermore, the degradation of sensitive cysts, as expressed by the degradation constant k and reaction time t, has been related to bottom water [O2]. The studied sediments were taken from the Arabian Sea, north-western African Margin (North Atlantic), western-equatorial Atlantic Ocean/Caraibic, south-western African margin (South Atlantic) and Southern Ocean (Atlantic sector). Significant relationships are observed between (a) accumulation rates of R-cysts and upper water chlorophyll-a concentrations, (b) accumulation rates of S-cysts and bottom water [O2] and (c) degradation rates of S-cysts (kt) and bottom water [O2]. Relationships that are extremely weak or are clearly insignificant on all confidence intervals are between (1) S-cyst accumulation rates and chlorophyll-a concentrations, sea-surface temperature (SST), sea-surface salinity (SSS), phosphate concentrations (P) and nitrate concentrations (N), (2) between R-cyst accumulation rates and bottom water [O2], SST, SSS, P and N, and between (3) kt and water depth. Co-variance is present between the parameters N and P, N, P and chlorophyll-a, oxygen and water depth. Correcting for this co-variance does not influence the significance of the relationship given above. The possible applicability of dinoflagellate cyst degradation to estimate past net primary production and deep ocean ventilation is discussed.

Magnetic analyses of ODP Hole 119-738B sediments

Magnetotactic bacteria intracellularly biomineralize magnetite of an ideal grain size for recording palaeomagnetic signals. However, bacterial magnetite has only been reported in a few pre-Quaternary records because progressive burial into anoxic diagenetic environments causes its dissolution. Deep-sea carbonate sequences provide optimal environments for preserving bacterial magnetite due to low rates of organic carbon burial and expanded pore-water redox zonations. Such sequences often do not become anoxic for tens to hundreds of metres below the seafloor. Nevertheless, the biogeochemical factors that control magnetotactic bacterial populations in such settings are not well known. We document the preservation of bacterial magnetite, which dominates the palaeomagnetic signal throughout Eocene pelagic carbonates from the southern Kerguelen Plateau, Southern Ocean. We provide evidence that iron fertilization, associated with increased aeolian dust flux, resulted in surface water eutrophication in the late Eocene that controlled bacterial magnetite abundance via export of organic carbon to the seafloor. Increased flux of aeolian iron-bearing phases also delivered iron to the seafloor, some of which became bioavailable through iron reduction. Our results suggest that magnetotactic bacterial populations in pelagic settings depend crucially on particulate iron and organic carbon delivery to the seafloor.

Flux of biomarkers and organisms at AWI HAUSGARTEN from two moorings

Time-series sediment traps were deployed at 4 depths in the eastern Fram Strait from July 2007 to June 2008 to investigate variations in the magnitude and composition of the sinking particulate matter from upper waters to the seafloor. Sediment traps were deployed at 196 m in the Atlantic Water layer, at 1296 and 2364 m in the intermediate and deep waters, and at 2430 m on a benthic lander in the near-bottom layer. Fluxes of total particulate matter, particulate organic carbon, particulate organic nitrogen, biogenic matter, lithogenic matter, biogenic particulate silica, calcium carbonate, dominant phytoplankton cells, and zooplankton fecal pellets increased with depth, indicating the importance of lateral advection on fluxes in the deep Fram Strait. The lateral supply of particulate matter was further supported by the constant fluxes of biomarkers such as brassicasterol, alkenones, campesterol, beta-sitosterol, and IP25 at all depths sampled. However, enhanced fluxes of diatoms and appendicularian fecal pellets from the upper waters to the seafloor in the presence of ice during spring indicated the rapid export (15-35 days) of locally-produced large particles that likely contributed most of the food supply to the benthic communities. These results show that lateral supply and downward fluxes are both important processes influencing the transport of particulate matter to the seafloor in the deep eastern Fram Strait, and that particulate matter size dictates the prevailing sinking process.

Stable carbon and oxygen isotope ratios of benthic and planktonic foraminifera of ODP Hole 171-1049C

Ocean anoxic events were periods of high carbon burial that led to drawdown of atmospheric carbon dioxide, lowering of bottom-water oxygen concentrations and, in many cases, significant biological extinction (Arthur et al., 1990; Erbacher et al., 1996, doi:10.1130/0091-7613(1996)024<0499:EPORAO>2.3.CO;2; Kuypers et al., 1999, doi:10.1038/20659; Jenkyns, 1997; Hochuli et al., 1999, doi:10.1130/0091-7613(1999)027<0657:EOHPAC>2.3.CO;2). Most ocean anoxic events are thought to be caused by high productivity and export of carbon from surface waters which is then preserved in organic-rich sediments, known as black shales. But the factors that triggered some of these events remain uncertain. Here we present stable isotope data from a mid-Cretaceous ocean anoxic event that occurred 112 Myr ago, and that point to increased thermohaline stratification as the probable cause. Ocean anoxic event 1b is associated with an increase in surface-water temperatures and runoff that led to decreased bottom-water formation and elevated carbon burial in the restricted basins of the western Tethys and North Atlantic. This event is in many ways similar to that which led to the more recent Plio-Pleistocene Mediterranean sapropels, but the greater geographical extent and longer duration (~46 kyr) of ocean anoxic event 1b suggest that processes leading to such ocean anoxic events in the North Atlantic and western Tethys were able to act over a much larger region, and sequester far more carbon, than any of the Quaternary sapropels.

Concentrations of organic carbon and organic matter isotopic compositions of sapropels and adjacent marls from ODP Hole 161-974B in the Tyrrhenian Basin (Table 1)

Multiple layers of sapropels occur widely in the sedimentary record of the Mediterranean Sea and record repetitions of paleoclimatic conditions that favored increased production and preservation of marine organic matter. A combination of hydrogen and carbon isotope analyses of Pleistocene sapropels from the Tyrrhenian Sea reveals new aspects of the factors leading to their deposition. Organic matter dD values that are significantly more negative in sapropels than in adjacent marls indicate a combination of dilution of surface waters by meteoric waters and increased burial of lipid-rich organic matter during periods of sapropel deposition. Organic d13C values in sapropels that are less negative than those in marls suggest periods of markedly elevated marine biological production. The opposite but concordant excursions of these two isotopic parameters imply that the sapropel layers formed from increased export of marine organic matter from the photic zone to the sea floor during periods of greater fluvial delivery of continental nutrients to the Mediterranean Sea. Furthermore, the isotopic evidence indicates that periods of wetter climate were widespread in southern Europe at the same times as in northern Africa.

Seawater carbonate chemistry and its effects on properties and sinking velocity of aggregates of the coccolithophore Emiliania huxleyi, 2010

Coccolithophores play an important role in organic matter export due to their production of the mineral calcite that can act as ballast. Recent studies indicated that calcification in coccolithophores may be affected by changes in seawater carbonate chemistry. We investigated the influence of CO2 on the aggregation and sinking behaviour of the coccolithophore Emiliania huxleyi (PML B92/11) during a laboratory experiment. The coccolithophores were grown under low (~180 µatm), medium (~380 µatm), and high (~750 µatm) CO2 conditions. Aggregation of the cells was promoted using roller tables. Size and settling velocity of aggregates were determined during the incubation using video image analysis. Our results indicate that aggregate properties are sensitive to changes in the degree of ballasting, as evoked by ocean acidification. Average sinking velocity was highest for low CO2 aggregates (~1292 m d-1) that also had the highest particulate inorganic to particulate organic carbon (PIC/POC) ratio. Lowest PIC/POC ratios and lowest sinking velocity (~366 m d-1) at comparable sizes were observed for aggregates of the high CO2 treatment. Aggregates of the high CO2 treatment showed a 4-fold lower excess density (~4.2*10**-4 g cm**-3) when compared to aggregates from the medium and low CO2 treatments (~1.7 g*10**-3 cm**-3). We also observed that more aggregates formed in the high CO2 treatment, and that those aggregates contained more bacteria than aggregates in the medium and low CO2 treatment. If applicable to the future ocean, our findings suggest that a CO2 induced reduction of the calcite content of aggregates could weaken the deep export of organic matter in the ocean, particularly in areas dominated by coccolithophores.

Seawater carbonate chemistry and shell length of Mediterranean pteropod Cavolinia inflexa larvae during experiments

Larvae of the Mediterranean pteropod Cavolinia inflexa were maintained at controlled pHT values of 8.1, 7.82 and 7.51, equivalent respectively to pCO2 levels of 380, 857 and 1713 µatm. At pHT 7.82 larvae exhibited malformations and lower shell growth, compared to the control condition. At pHT 7.51 the larvae did not make shells but were viable and showed a normal development. However, smaller shells or no shells will have both ecological (food web) and biogeochemical (export of carbon and carbonate) consequences. These results confirm that 1pteropods, as well as the species dependent upon them as a food resource, will be severely impacted by ocean acidification.

Concentrations and abundance ratios of long-chain alkenones and glycerol dialkyl glycerol tetraethers in sinking particles south of Java

In this study, we obtained concentrations and abundance ratios of long-chain alkenones and glycerol dialkyl glycerol tetraethers (GDGTs) in a one-year time-series of sinking particles collected with a sediment trap moored from December 2001 to November 2002 at 2200 m water depth south of Java in the eastern Indian Ocean. We investigate the seasonality of alkenone and GDGT fluxes as well as the potential habitat depth of the Thaumarchaeota producing the GDGTs entrained in sinking particles. The alkenone flux shows a pronounced seasonality and ranges from 1 µg m-**2 d**-1 to 35 µg m**-2 d**-1. The highest alkenone flux is observed in late September during the Southeast monsoon, coincident with high total organic carbon fluxes as well as high net primary productivity. Flux-weighted mean temperature for the high flux period using the alkenone-based sea-surface temperature (SST) index UK'37 is 26.7°C, which is similar to satellite-derived Southeast (SE) monsoon SST (26.4°C). The GDGT flux displays a weaker seasonality than that of the alkenones. It is elevated during the SE monsoon period compared to the Northwest (NW) monsoon and intermonsoon periods (approximately 2.5 times), which is probably related to seasonal variation of the abundance of Thaumarchaeota, or to enhanced export of GDGTs by aggregation with sinking phytoplankton detritus. Flux-weighted mean temperature inferred from the GDGT-based TEXH86 index is 26.2°C, which is 1.8 °C lower than mean annual (ma) SST but similar to SE monsoon SST. As the time series of TEXH86 temperature estimates, however, does not record a strong seasonal amplitude, we infer that TEXH86 reflects ma upper thermocline temperature at approximately 50 m water depth.

Flux data of NU2_trap (Table A1)

Flux of bulk components, carbonate- and silicate-bearing skeleton organisms, and the d15N-isotopic signal were investigated on a 1-year time-series sediment trap deployed at the pelagic NU mooring site (Namibia Upwelling, ca. 29°S, 13°E) in the central Benguela System. The flux of bulk components mostly shows bimodal seasonality with major peaks in austral summer and winter, and moderate to low export in austral fall and spring. The calcium carbonate fraction dominates the export of particulates throughout the year, followed by lithogenic and biogenic opal. Planktonic foraminifera and coccolithophorids are major components of the carbonate fraction, while diatoms clearly dominate the biogenic opal fraction. Bulk d15N isotopic composition of particulate matter is positively correlated with the total mass flux during summer and fall, while negatively correlated during winter and spring. Seasonal changes in the intensity of the main oceanographic processes affecting the NU site are inferred from variations in bulk component flux, and in the flux and diversity patterns of individual species or group of species. Influence from the Namaqua (Hondeklip) upwelling cell through offshore migration of chlorophyll filaments is stronger in summer, while the winter flux maximum seems to reflect mainly in situ production, with less influence from the coastal and shelf upwelling areas. On a yearly basis, dominant microorganisms correspond well with the flora and fauna of tropical/subtropical waters, with minor contribution of near-shore organisms. The simultaneous occurrence of species with different ecological affinities mirrors the fact that the mooring site was located in a transitional region with large hydrographic variability over short-time intervals.

Analysis of the Market Potential of Syrian Organic Fruit and Vegetables for Exports to Germany

Syria has been a major producer and exporter of fresh fruit and vegetables (FFV) in the Arabic region. Prior to 2011, Syrian FFV were mainly exported to the neighbouring countries, the Gulf States and Northern Africa as well as to Eastern European countries. Although the EU is potentially one of the most profitable markets of high quality FFV (such as organic ones) in the world, Syrian exports of FFV to Western European countries like Germany have been small. It could be a lucrative opportunity for Syrian growers and exporters of FFV to export organic products to markets such as Germany, where national production is limited to a few months due to climatic conditions. Yet, the organic sector in Syria is comparatively young and only a very small area of FFV is certified according to EU organic regulations. Up to the author’s knowledge, little was known about Syrian farmers’ attitudes towards organic FFV production. There was also no study so far that explored and analysed the determining factors for organic FFV adoption among Syrian farmers as well as the exports of these products to the EU markets. The overarching aim of the present dissertation focused on exploring and identifying the market potential of Syrian exports of organic FFV to Germany. The dissertation was therefore concerned with three main objectives: (i) to explore if German importers and wholesalers of organic FFV see market opportunities for Syrian organic products and what requirements in terms of quality and quantity they have, (ii) to determine the obstacles Syrian producers and exporters face when exporting agricultural products to Germany, and (iii) to investigate whether Syrian farmers of FFV can imagine converting their farms to organic production as well as the underlying reasons why they do so or not. A twofold methodological approach with expert interviews and a farmer survey were used in this dissertation to address the abovementioned objectives. While expert interviews were conducted with German and Syrian wholesalers of (organic) FFV in 2011 (9 interviews each), the farmer survey was administrated with 266 Syrian farmers of FFV in the main region for the production of FFV (i.e. the coastal region) from November 2012 till May 2013. For modelling farmers’ decisions to adopt organic farming, the Theory of Planned Behaviour as theoretical framework and Partial Least Squares Structural Equation Modelling as the main method for data analysis were used in this study. The findings of this dissertation yield implications for the different stakeholders (governmental institutions and NGOs, farmers, exporters, wholesalers, etc.) who are interested in prompting the Syrian export of organic products. Based on the empirical results and a literature review, an action plan to promote Syrian production and export of organic products was developed which can help in the post-war period in Syria at improving the organic sector.

Micro-Foundations of Financialization. Status Anxiety and the Market for Consumer Credit in Chile

This project investigates why people in Chile acquired so much consumer debt in contexts of material prosperity, and asks what the role of inequality and commodification is in this process. The case raises an important challenge to the literature. Insofar as existing accounts assume that the financialization of consumption occurs in contexts marked by wage stagnation and a general deterioration of the middle classes, they engender two contradictory explanations: while political economists argue that people use credit in order to smooth their consumption in the face of market volatility, economists maintain that concentration of wealth at the top pushes middle income consumers to emulate the expenditures of the rich and consume beyond their means. These explanations do not necessarily fit the reality of developing countries. Triangulating in-depth interviews with middle class families, multivariate statistical analysis and secondary literature, the project shows that consumers in Chile use credit to finance “ordinary” forms of consumption that do not aim either at coping with market instability or emulating and signaling status to others. Rather, Chileans use department store credit cards in order to acquire a standard package of “inconspicuous” goods that they feel entitled to have. From this point of view, the systematic indebtedness of consumers originates in a major concern with “rank”, “achievement” and "security" that – following De Botton -- I call “status anxiety”. Status anxiety does not stem from the desire to emulate rich consumers, but from the impossibility of complying with normative expectations about what a middle class family should be (and have) that outweigh wage improvements. The project thus investigates the way in which “status anxiety” is systematically reproduced by means of two broad mechanisms that prompt people to acquire consumer debt. The first mechanism generating debt stems from an increase of real wages and high levels of inequality. It is explained by a general sociological principle known as relative deprivation, which points to the fact that general satisfaction with one´s income, possessions or status, is assessed not in absolute terms such as total income, but in relation with reference groups. In this sense, I explore the mechanisms that operate as catalyzers of relative deprivation, by making explicit social inequalities and distorting the perception of others´ wealth. Despite upward mobility and economic improvement, Chileans share the perception of “falling behind,” which materializes in an “imaginary middle class” against which people compare their status, possessions and economic independence. Finally, I show that the commodification of education, health and pension funds does not directly prompt people to acquire consumer debt, but operate as “income draining” mechanisms that demand higher shares of middle class families’ “discretionary income.” In combination with “relative deprivation,” these “income draining” mechanisms leave families with few options to perform their desired class identities, other than learning how to bring resources from the future into the present with the help of department store credit cards.

Children of Matter: Luxury Value Perceptions of Millennials in Higher Education in Europe

In recent years, the luxury market has entered a period of very modest growth, which has been dubbed the ‘new normal’, where varying tourist flows, currency fluctuations, and shifted consumer tastes dictate the terms. The modern luxury consumer is a fickle mistress. Especially millennials – people born in the 1980s and 1990s – are the embodiment of this new form of demanding luxury consumer with particular tastes and values. Modern consumers, and specifically millennials, want experiences and free time, and are interested in a brand’s societal position and environmental impact. The purpose of this thesis is to investigate what the luxury value perceptions of millennials in higher education are in Europe, seeing as many of the most prominent luxury goods companies in the world originate from Europe. Perceived luxury value is herein examined from the individual’s perspective. As values and value perceptions are complex constructs, using qualitative research methods is justifiable. The data for thesis has been gathered by means of a group interview. The interview participants all study hospitality management in a private college, and each represent a different nationality. Cultural theories and research on luxury and luxury values provide the scientific foundation for this thesis, and a multidimensional luxury value model is used as a theoretical tool in sorting and analyzing the data. The results show that millennials in Europe value much more than simply modern and hard luxury. Functional, financial, individual, and social aspects are all present in perceived luxury value, but some more in a negative sense than others. Conspicuous, status-seeking consumption is mostly frowned upon, as is the consumption of luxury goods for the sake of satisfying social requisites and peer pressure. Most of the positive value perceptions are attributed to the functional dimension, as luxury products are seen to come with a promise of high quality and reliability, which justifies any price premiums. Ecological and ethical aspects of luxury are already a contemporary trend, but perceived even more as an important characteristic of luxury in the future. Most importantly, having time is fundamental. Depending on who is asked, luxury can mean anything, just as much as it can mean nothing.

Using Quantitative Methods to Explore Political Leverage, Trade Policy, and Food Security: A Case Study of the Middle East

This dissertation explores why some states consistently secure food imports at prices higher than the world market price, thereby exacerbating food insecurity domestically. I challenge the idea that free market economics alone can explain these trade behaviors, and instead argue that states take into account political considerations when engaging in food trade that results in inefficient trade. In particular, states that are dependent on imports of staple food products, like cereals, are wary of the potential strategic value of these goods to exporters. I argue that this consideration, combined with the importing state’s ability to mitigate that risk through its own forms of political or economic leverage, will shape the behavior of the importing state and contribute to its potential for food security. In addition to cross-national analyses, I use case studies of the Gulf Cooperation Council states and Jordan to demonstrate how the political tools available to these importers affect their food security. The results of my analyses suggest that when import dependent states have access to forms of political leverage, they are more likely to trade efficiently, thereby increasing their potential for food security.