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Biodiversity loss could jeopardize ecosystem functioning. Yet, the evidences that support this demonstration have been mostly obtained in aquatic and grassland ecosystems. Howbiodiversity affects ecosystem functioning still remain largely unanswered in forests, particularly in subtropical broad-leaved evergreen forests (EBLF). Tree productivity, among a wealth of forest ecosystem functioning, is of particular interest because it reflects the carbon sink capacity and wood productivity. Biodiversity-productivity relationships have been usually investigated at community level. However, tree-tree interactions occur at small scale. Thus, local neighborhood approach may allow a better understanding of tree-tree interactions and their contributions to the effects of biodiversity on tree productivity / growth rates. This thesis aims to analyze the effects of biodiversity and the abiotic environmental factors on the tree growth rates using both local neighborhood and community-based approaches. Furthermore, tree growth rates vary among different tree species. Functional traits have been related to the species-specific growth rates to understand the effects of species identity. Therefore, I also evaluated the crown- and leaf traits to predict the interspecific difference in growth rates. For a better understanding of the mechanisms that underline the relationships of biodiversity and tree growth rates, data of high solution and along time series is required to scrutinize the tree-tree interactions. Thereupon, I evaluated the applicability of terrestrial laser scanning (TLS) in assessing the tree dendrometrics. This thesis was conducted in the Biodiversity Ecosystem Functioning (BEF)–China experiment, which is located in a mountainous subtropical region in southeast China. A total of 40 native broad-leaved tree species were planted. In the first study, I used the local neighborhood approach to analyze how local abiotic conditions (i.e. topographic and edaphic conditions) and local neighborhood (i.e. species diversity and competition by neighborhood) affect the annual growth rates of 6723 individual trees. The second study used the community approach to partition the effects of environmental factors (i.e. topographic and edaphic), functional diversity according to Rao’s quadratic entropy (FDQ) and community weight mean (CWM) of 41 functional traits on community tree growth rates. The main question of the third study was how the species-specific growth rates are related to five crown- and 12 leaf traits.
In the fourth study, I investigated 438 tree individuals for the congruence between the conventional direct field measurements and TLS measurements. It was found that tree growth rates were strongly influenced by the local topographic and edaphic conditions but not affected by the diversity of local neighborhood. In contrast, results obtained by using the community-based approach showed that FDQ and CWMs of various leaf traits rather than abiotic environmental factors had significant impact on the community means of growth rates. Tree-tree interactions already occur in early life stages of trees, which were evidenced by the significant effect of competition by local neighborhood. These findings imply that the effects of abiotic environmental factors may be more evident at local scale and biodiversity effects may vary at different spatial scales. The species-specific growth rates were found to be related to specific leaf traits but not to crown traits and were best explained by both types of traits in combination. This finding supports the niche theory and provides the evidence for using functional diversity to examine the BEF relationships. The TLS-retrieved total tree height, stem diameter at 5 cm above ground, and length and height of the longest branch were highly congruent with those obtained from direct measurements. It indicates that TLS is a promising tool for high resolution, non-destructive analyses of tree structures in young tree plantations. Being one of very few studies to incorporate the individual tree scale in examining the biodiversity-productivity relationships within the BEF researches, this thesis stresses the importance of using individual-tree based approach, functional diversity and TLS to find the evidences of explanatory mechanisms of the observed biodiversity and ecosystem functioning (e.g. tree growth rates) relationships. Biodiversity effects may evolve along the successional stages. Therefore, incorporating the interaction between biodiversity and time in analyzing BEF relationship is also encouraged.
Agricultural production of smallholder farmers in Myanmar is facing soil fertility degradation and in consequence, crop yields decline due to the imbalances of nutrient supply. In most cases, all above ground biomass is removed from the fields after harvesting the crops and during land preparation for the next crop. Higher temperatures also stimulate the higher mineralisation rates and released mineral nutrients are lost from fallow lands before sowing the next crops. Regarding the addition of mineral fertilizers, except for cash crops, farmers are reluctant to apply fertilizers for the crops that are sown for household’s self-sufficiency. In the Dry Zone, irrigated agriculture is available in recent years and farmers could overcome water scarcity through irrigation. With the availability of irrigation water, farmers could prolong the cropping period, nevertheless crop yields are decreasing year by year. In recent decades, research findings are indicating the benefits of biochar application for soil fertility improvement and food security. Smallholder farmers can produce biochar from agricultural by-products such as pigeon pea stems, cotton stems and rice husks by using biochar stoves. Large-scale production is possible by producing both biochar and thermal energy simultaneously, such as getting rice husk biochar and producing thermal energy by burning rice husks. By those means, environmental pollution due to the smokes from stubble burnings and the health hazards from smokes arise from kitchens can also be reduced. Present research was conducted to test the effects of the application of biochars produced from different crop residues together with NPK fertilizers on crop yields and soil properties in the rice-chickpea-cotton cropping system of the Central Dry Zone area of Myanmar during 2012 and 2013 cropping seasons at Shwe Daung Farm, Mandalay Division, Myanmar. Effects of biochar applications in combination with NPK fertilizers were compared with NPK fertilizer (without biochar) application and the control (without biochar and NPK fertilizers). Biochars used in the experiments were produced from three kinds of locally available raw materials (rice husk, rice straw and, pigeon pea stem) at temperature above 550°C by using a kiln made from a 200-Liter diesel barrel. Field experiments were conducted on sandy loam soil in the Central Dry Zone of Myanmar. After harvesting rice in 2012, chickpea was sown without application of both organic and inorganic fertilizers. After harvesting chickpea in 2013, cotton was sown on the same experimental plots. Treatments were rice husk biochar (Rh) 20 Mg ha-1 + NPK fertilizers; rice straw biochar (Rs) 20 Mg ha-1 + NPK fertilizers; pigeon pea stem biochar (Ps) 20 Mg ha-1 + NPK fertilizers; rice husk biochar and farmyard manure mixture (Rh biochar + FYM) 10 Mg ha-1 + NPK fertilizers; NPK fertilizers (without biochar); and the control (without fertilizer and biochar). Biochar weights represented fresh biochar weights. Equal rate of NPK fertilizers were applied in all treatments. However, fertilizer rates were different with respect to the crops. In rice experiment, 100:50:50 kg ha-1 rate of Urea (N): Triple Super Phosphate (P): Muriate of potash (K) was applied. In cotton experiment, 100:30:117 kg ha-1 rate of Urea (N): Triple Super Phosphate (P): Muriate of potash (K) was applied. Crop growth data, yield component data and yield data of each treatment were recorded. Soil samples from topsoil (0-0.2 m) were taken before starting the experiments, after harvesting rice and cotton, respectively, and analysed. A biogeochemical model, denitrification decomposition (DNDC) model, was used to estimate soil organic carbon storage and greenhouse gas emissions during crop growing seasons and to quantify the long-term impact of biochar applications on rice, chickpea and cotton yields.The results from soil analyses indicated that although initial soil pH was at 8.0 and pH values of biochars ranged between 8.0 and 10.0 soil pH after two years of biochar application did not increase. pH values were below 8.0. That value was lower than initial soil pH. That could be due to the effect of the change of cropping system from upland to lowland rice cultivation and the effects of biochar additions to the alkaline sandy loamy soil of the experimental site. Although total exchangeable cation value was not significantly different among the treatments, compositions of major cations were significantly different among the treatments. Exchangeable potassium increased in Rs biochar + NPK applied soils. Exchangeable sodium increased in control, and conventional NPK fertilizer applied soils. Reduction of soil bulk density from 1.8 g cm-3 to 1.6-1.7 g cm-3 occurred in biochar treatments compared to control and conventional NPK fertilizer application treatments. Positive changes of total carbon and total nitrogen of soils were found in biochar treatments compared to control and conventional NPK fertilizer application. Application of pigeon pea stem biochar + NPK fertilizers showed the highest crop growth and the highest yield in rice. The highest chickpea yield was obtained from the plot that applied rice husk biochar + NPK fertilizers. Cotton crop growth and yield was the highest in rice husk biochar and farmyard manure mixture + NPK fertilizer application. The lowest crop growth and yield was obtained from the control in cotton. The results of this study suggested that biochars from different biomass materials had different effects on soil properties and crop yields under different growing conditions and cultivated crops. Although the applied biochars had a high pH, soil pH did not increase after biochar applications. The growth and yield of tested crops were higher than that of the control and conventional NPK fertilizer application. Rice husk biochar and farmyard manure mixture + NPK fertilizer application can be assumed as a suitable soil amendment application under upland crop cultivation. Pigeon pea stems biochar + NPK fertilizers should be applied in rice cultivation. Rice husk biochar + NPK fertilizers and rice husk biochar-farmyard manure mixture + NPK fertilizers showed as the appropriate biochar soil amendments for the study area compared to rice straw biochar + NPK fertilizers and pigeon pea stem biochar + NPK fertilizers. Application of these biochars increased total exchangeable cations, reduced bulk density, increased organic carbon, regulated soil pH and, can easily be accessed by smallholder farmers by promising crop yields for sustainable agricultural production. Rice straw biochar + NPK fertilizers and pigeon pea stem biochar + NPK fertilizers also showed positive influences on soil fertility and crop growth. However, extensive application of those biochars might require large-scale productions and distributions. To obtain the detail information regarding the impact of biochar application on the agro-ecosystem and surrounding atmosphere, further research activities may need to carry out under different agricultural production conditions. When model fitness was tested, it was found that DNDC model was fit for the simulation of crop yields and soil organic carbon under the conditions of the experimental site. Simulation of soil organic carbon dynamics and crop yields for 30 years and 50 years after the addition of biochars in combination with NPK fertilizers showed that such applications could maintain the crop yields at the same level up to 50 years. That could maintain soil organic carbon at a level higher than conventional NPK fertilizer application. Regarding the simulation of GHGs emissions, the model simulated nitrous oxide emission close to actual emissions of agricultural soils of Myanmar. Simulated CH4 emissions from control and conventional NPK fertilizer application variant were consistent with the well-known emissions of Myanmar rice fields. To confirm the accuracy of simulated CH4 emissions from biochar applied soils, it may need field investigations and validations of model results. Simulated effects of rice husk-, rice straw- and pigeon pea stem fresh biomass applications and that of rice husk-, rice straw- and pigeon pea stem biochar applications on rice, chickpea, cotton yields and soil organic carbon (SOC) were compared. Objective of this simulation was to compare the effects of fresh biomass-applications and the application of biochars produced from the same biomass on crop yields and SOC by using DNDC model. The results showed that simulated rice yields of rice husk biochar and rice straw biochar applications were 33% and 31%, respectively, higher than that of pigeon pea green manure applications. However, simulated rice yield from pigeon pea stem biochar application was 4% higher than that of iv pigeon pea stem green manure application. Simulated chickpea yield from pigeon pea green manure treatment was the highest among all of biochar and biomass applications. Simulated cotton yields obtained from fresh biomass applications were lower than that of biochar applications. In estimating the future yields, all crop yields from rice husk and rice straw biomass applications were lower than that of rice husk and rice straw biochar applications in the initial year of simulation. However, in the following years, the yields remained at the same level up to the end of simulated years. In pigeon pea stem green manure application, crop yields were higher than the other treatments since the initial year up to the end of simulated years. Simulated SOC was lower in fresh biomass applications compared to biochar applications.
Despite the great progress that has been made in the prophylaxis of oral diseases over the past decades, dental caries and periodontal diseases remain major challenges in the field of dentistry. Biofilm formation on dental hard tissues is strongly associated with the etiology of these oral diseases. Therefore, the process of bioadhesion and biofilm formation on tooth surfaces is of particular interest for dental research. The first stage of bioadhesion on dental surfaces is the formation of the pellicle layer. This mainly acellular film, composed largely of adsorbed proteins, glycoproteins, and lipids, is distinguished from the microbial biofilm (plaque). As the interface between teeth and the oral environment, the pellicle plays a key role in the maintenance of oral health and is of great physiological and pathophysiological importance. On the one hand, the pellicle shows protective properties for the underlying dental hard tissues. On the other hand, it also serves as the basis for dental plaque and therefore, for the development of oral diseases such as caries and periodontitis. Hydrophobic interactions, which are governed by lipophilic substances, are of high relevance for bacterial adherence. Therefore, pellicle lipids, which are a significant constituent of this biological structure, are an interesting target for dental research, as they could modulate oral surfaces, influence microbial interactions, and potentially impede bacterial adherence. Compared to the extensive work on the pellicle´s ultrastructure and protein/amino acid composition, little attention has been given to its lipid profile. Knowledge of the lipid composition of the pellicle may provide insight into several oral pathological states, including caries, dental erosion, and periodontal disease processes and could contribute to novel approaches in preventive dentistry. The principle aim of this thesis was the comprehensive characterization of the fatty acid (FA) profile of the in situ formed pellicle layer. This includes the influence of pellicle maturation on the FA profile as well as intra- and interindividual differences. Furthermore, investigations on the effect of rinses with edible oils on the pellicle´s FA composition were a focus of this work. For these purposes, an analytical method based on a combination of innovative specimen generation and convenient sample preparation with sensitive mass spectrometric analysis was successfully developed and comprehensively validated within this thesis. Pellicle samples were formed in situ on bovine enamel slabs mounted on individual upper jaw splints. After a comprehensive sample preparation, gas chromatography coupled with electron impact ionization mass spectrometry (GC-EI/MS) was used in order to characterize qualitatively and quantitatively a wide range of FA (C12-C24). The individual FA profiles of pellicle and saliva samples collected from ten research participants were investigated. The relative FA profiles of the pellicle samples gained from the different subjects were very similar, whereas the amount of FAs showed significant interindividual variability. Compared to the pellicle´s characteristic FA profile, higher proportions of unsaturated FAs were detected in the saliva samples, highlighting that FAs available in saliva are not adsorbed equivalently to the pellicle layer. This, in turn, shows that pellicle formation is a highly selective process that does not correlate directly with salivary composition. Additionally, pellicle samples collected after 3, 30, 60, 120, and 240 min of intraoral exposure were analyzed. It could be shown that pellicle maturation has only a minor impact on the FA composition. However, the FA content increased substantially with increasing oral exposure time. Modifying the pellicle´s lipid composition by using edible oils as a mouthwash could alter the physicochemical characteristics of the pellicle and strengthen its protective properties by delaying bacterial adhesion. Therefore, the impact of rinses with safflower oil on the pellicle´s FA composition was determined. The application of rinses with safflower oil resulted in an accumulation of its specific FAs in the pellicle, thus representing a possibility for modifying the pellicle´s lipid profile. The present work is the first to apply a validated method that combines in situ pellicle formation, sample preparation, and the comprehensive determination of FAs via a sensitive analytical method. The results provide valuable information regarding the pellicle´s FA composition which closes an existing knowledge gap in pellicle research. A broader knowledge of the lipid composition of the pellicle contributes to the understanding of oral bioadhesion processes and may help facilitate novel approaches in preventive dentistry.
Prospective students´ choice of their university is a topic of rising relevance worldwide. As competition on the higher education market and the resultant fight for students increases, universities need to deal with questions of how, when, and why young people decide where to study. This knowledge forms the basis for developing adequate and effective communication strategies enabling university marketers to recruit the best and most suitable students for their institutions. Despite extensive research on these questions, there still are fundamental gaps like the nonobservance of sense making activities, the neglected role of emotions and higher education policies, the suboptimal choice of research methods as well as problematic theoretical assumptions previous research is based upon. In this dissertation, I address all of these gaps in three complementary articles. In the first paper, I compare American with German research on university choice by focusing on the three aspects of theoretical approaches applied in previous studies, choice factors, and information sources prospective students use. On the basis of this literature review, I identify major research gaps with a focus on, but not limited to, the German context. In the second article, by using the Zaltman Metaphor Elicitation Technique (ZMET), I identify mental models of prospective students that represent their sense making activities. Through this, I get a profound understanding of which rational and especially emotional issues are relevant for the students when they try to make sense of the marketing messages they are confronted with during their university choice process. In the third paper, I challenge the theoretical approaches previous research is based upon by identifying two very different types of decision-makers with their respective choice strategies and logics. Overall, this dissertation contributes to a much more detailed understanding of prospective students´ university choices by identifying their sense-making activities and choice styles, highlighting the role of emotions and context factors, and refining the theoretical foundations university choice research is based upon.
The future of forests is closely linked to climate change and energy transition because the preconditions for forest management are changed through climate and energy policies (Beland Lindahl and Westholm 2012). Forest management has multiple objectives, and different stakeholders have competing interests in forests. A strong dichotomy between environmental and economic interests has characterized forest policy and most conflicts about forests in the past (Winkel and Sotirow 2011). Climate change and energy transition modify this established conflict line because new conflicts related to climate mitigation, climate adaptation, and renewable energies have blurred the clear opposition between environmental and economic interest (Mautz 2010). In the context of the new challenges of climate change and energy transition, the need for effective, efficient and legitimate forest governance is gaining a new importance. Based on 86 qualitative interviews about forest conflicts and forest governance in five qualitative case studies, theoretical approaches focusing on multi-level and multi-scale governance are merged with the field of environmental and natural resource conflict research in this thesis. Forest conflicts and their governance are a multi-level and multi-scale issue. However, not so much is known about how collective and individual state and non-state actors act in complex governance systems and how they perceive governance systems. In order to contribute to the understanding of these knowledge gaps, this thesis tests the applicability of three theoretical perspectives on multiple scales and levels of decision-making (multi-level governance, polycentricity, politics of scale) to fruitfully study forest conflicts. Furthermore, the thesis provides empirical insights about forest conflicts in the face of energy transition and climate change. Based on the theoretical and empirical findings, this thesis provides practical recommendations to policy makers and practitioners on how to improve governance in forestry and the management of other natural resources. For example, this thesis shows the importance of considering different actor constellations in participatory processes at different governance levels, and that not every actor will react the same way to a certain method of decision-making. Furthermore, this thesis illustrates how trust building measures, such as enhanced communication between stakeholders, transparency in decision-making and forest education can reduce the risk of destructive conflict escalation. This thesis also demonstrates that energy transition and the discussion about climate change are sources of new conflicts, can change old conflicts, and add new, additional levels to forest governance. Thus, climate change and energy transition cause further fragmentation of forest governance and make forest governance more multi-level, create additional venue-shopping opportunities, and bring new actors into forest governance, causing new power constellations in the policy field. Forest governance is in a reconfiguration process which can be conceptualized as shift towards multi-level governance. Level choice and the relation of state and non-state actors in decision-making are important aspects of governance, thus the theoretical approach has yielded valuable insights in forest conflicts and the importance of scale construction in conflict discourses can be illustrated. Different levels are associated with different functions, strengths, and weaknesses of stakeholders; the perceptions of appropriate scale choice are often based on frames. The empirical findings have shown that level choice is often a normative and/or cultural decision, often no objective ´best´ decision-making level exists. Some actors consider different competing, overlapping, and nested decision-making levels to be an opportunity for interest realization; others feel helpless and overwhelmed in complex, multi-level systems. Different re-scaling strategies (up-scaling, down-scaling, fit re-scaling) are applied by actors to realize their interests. Non-state actors have an important function in linking processes from different levels. However, multi-level governance and related concepts have their limits for the explanation of forest conflict processes because some important factors cannot be captured with this approach. For example, social-psychological factors and conflict frames are important for the understanding of conflict development and governance and at a local level individual action and the relations between individuals crucially set the preconditions for the governance of conflicts.
Heating is most important part of thermal energy demand, and accounts for large amounts ofenergy consumption in cold regions. Renewable energy sources will be of great importance inorder to cover future energy demands. However, their intermittency is rightly considered asinconvenient. Thus, a more effective management of demand, coupled with efficient storagesystems is required. Based on this perception, thermal systems coupled with electricityproduction have been efficiently designed, they are the so called “combined heat and power”(micro-CHP). Nonetheless, heat losses from the thermal part of their system lead to electricityfluctuation. Therefore, the use of micro-CHP in combination with a volume-efficient and nearlylossless heat storage system to counteract electricity fluctuations is a viable solution.The heat storage system in this work is based on reversible thermochemical reactions, suchas dehydration and hydration of inorganic salts, which exhibits very high energy density (up to628 kWh·m-3 of storage material). The chosen inorganic salt (SrBr2·6H2O) reacting with purewater vapour operates within a closed system. The objective of this work is to design a systemthat thermodynamically matches the combination with micro-CHP. Therefore, investigationshave been performed from the material at micro-scale to the system at lab-scale. Models weredeveloped on the basis of heat and mass transfer with chemical reaction and were done in orderto numerically analyse the system. Experiments were additionally performed to consolidate thenumerical tools for future studies. Characterization experiments have been designed and tested.Thermo-physical properties (thermal conductivity, specific heat capacity, permeability, chemicalkinetics) of the reactive salt were then determined to be used as parameters into the sodeveloped models.The numerical simulations lead to the time-space evolution of heating fluid, reactive bedtemperatures and reactor pressure. The originality of this study is to model the coupled heat andmass transfer with chemical reaction on a 3D geometry to be close to the reality. Results help tonumerically and experimentally analyse the thermochemical heat storage performances. Thebed energy density is experimentally found to be 531 kWh·m-3 of salt hydrate. Based on thecondensation temperature during the experimentation, a reactor energy density of 140 kWh·m-3and a storage capacity of 65 kWh with a thermal efficiency of 0.78 are obtained. This systemproves the recovery capacity of more than 2/3 of the input energy. Various aspects of design andrecommendation for optimisation aspect that could help during prototype development aretaken into account and addressed. Comparison simulation-experiment is then performed anddiscussed, showing encouraging results, even if limited at lab-scale.
Uranine (sodium fluorescein, UR) has been routinely used in hydrological research to monitor surface and subsurface water flow, transport and mixing processes since the end of nineteenth century. Based on such obtained data, further conclusions can be drawn on the spread and behavior of pollutants (partly on models). Use of UR for qualitative (visual) studies of underground contamination is common, however data available on its environmental behavior (e.g., conversion, degradation or formation and fate of the transformation products, TPs) are incomplete or not readily comparable. UR observations of biodegradation are still speculative. S-metolachlor (SM) is a popular worldwide chloroacetamide herbicide, which highly correspond to the global pesticide use. It is offered on the French market as an effective multicrop herbicide against annual grasses and certain broadleaf weeds under the trade name Mercantor Gold (MG). Photodegradation contributes to the fate of SM in the aquatic environment. TPs were already found in surface and groundwater. However, further fate and assessment of the TPs was not done. Moreover, adjuvants in MG´s formula can affect the solubility, biodegradation, photolysis and sorption properties of the active compound SM. TPs can have different properties (e.g. more mobile, toxic or present at higher concentrations) that enable them to reach the environmental compartments not affected by the parent compound (PC) itself. To assess the ecological impact of pesticides, tracers, and their respective TPs on water organisms, their behavior can be investigated in laboratory screening biodegradation tests. Yet, incomplete data was available on SM, MG and UR transformation or their photo- TPs´ fate in surface and water-sediment systems. The combination of photolysis with aerobic biodegradation in order to identify persistent photo-TPs could provide new insight into the environmental behavior of the selected compounds. Therefore, principle of this thesis was to 1) identify the impact of MG´s adjuvants on the biodegradation, photolysis (Xe lamp) and sorption compared to the SM alone, 2) examine the photolysis and biodegradability of UR 3) monitor the primary elimination (photolysis) of the PCs by HPLC (-UV, -FLD) and measure the degree of mineralization by means of nonpurgeable organic carbon (NPOC) 4) elucidate the photo-TPs of SM, MG and UR by using LCMS/ MS 5) analyze biodegradability of the photo-TPs in order to determine their fate and persistence in aquatic environment 6) conduct in silico toxicity predictions (pesticides) in human (carcinogenicity, genotoxicity and mutagenicity) and eco-toxicity (microtoxicity, bioconcentration factor and toxicity in rainbow trouts). SM, MG and UR were found not readily biodegradable in Closed Bottle test (CBT), Manometric Respiratory test (MRT) and in water-sediment test (WST). Chemical analysis of photolysis samples showed higher elimination of SM in MG compared to SM alone whereas UR displayed high primary elimination rate in general. The overall low degree of mineralization indicated that abundant photo-TPs were formed. Furthermore, the photo-TPs were found not biodegradable in performed biodegradation tests. Only small degradation rates for UR could be observed in the CBT and WST. Additionally, in the MRT and WST new bio-TPs were generated from the photo-TPs of SM and SM in MG. Obtained results suggest that the MG formulation did not significantly affect the biodegradation, however it influenced the diffusion of the active substance (SM) to sediment and potentially affected the photolysis efficiency, which might result in faster formation of photo-TPs in the environment. In silico predictions showed that for many endpoints, biotransformation might lead to an increased toxicity in humans and to water organisms compared with the parent compound SM. No indications were found for UR toxicity. Still, target-oriented investigations on long term impacts of photo-TPs from UR are warranted. The present work demonstrates that a combination of laboratory tests, analytical analysis and in silico tools result in valuable information regarding environmental fate of the TPs from selected compounds. Furthermore, it was shown that photo-TPs formed in the aquatic environment should be taken into account not only the parent compound and its decay.
In 1999 David Elstein delivered a lecture series examining the evolvement of UK broadcasting policy from 1949 to 1999. His sharp analysis is a valuable contribution to the post-war devel-opment of the British broadcasting system and unfolds many topical issues in current media policy debates.