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Wildunfälle stellen deutschlandweit und insbesondere in waldreichen Bundesländern wie Hessen zeitweise bis zu einem Drittel der Gesamtunfälle dar. Im Mittelpunkt der vorliegenden Dissertation steht die folgende Forschungsfrage:
Welche Parameter bestimmen die raum-zeitliche Verteilung von Wildunfällen und wie können Entscheidungsträger aus Politik, Wirtschaft und Verbänden aktuell und angesichts der technologischen Entwicklung eine bestmögliche Senkung der Unfallzahlen herbeiführen?
In einem zweiteiligen Ansatz wird zunächst eine Analyse der seitens der hessischen Polizei aufgenommenen Unfalldaten der Jahre 2006 bis 2016 durchgeführt, um Hypothesen zu den Einflussfaktoren zu beantworten. Aufbauend auf einem Forschungsprojekt der Bundesanstalt für Straßenwesen (BASt) werden die zehn gravierendsten hessischen Schwerpunktstrecken ermittelt und für diese eine Umfeldanalyse mit behördlichen GIS-Daten durchgeführt. Die Ergebnisse werden mit den Werten von zufallsbasiert gewählten, unfallunauffälligen Abschnitten verglichen. Weiterhin werden die o. g. über 170.000 Unfallreporte ausgewertet. Die Resultate der Analysen werden anhand der Fachliteratur mit dem aktuellen Stand der Forschung verglichen. Im zweiten Schritt wird die in die Unfallpräventionsarbeit involvierte Akteurslandschaft mittels Szenariotechniken zur Strategieentwicklung untersucht. Anhand der gewonnenen Erkenntnisse über die Dynamiken und Potenziale wird ein Handlungskonzept erarbeitet und mit Vertretern der Stakeholder diskutiert. Abschließend werden auf der Grundlage des in den beiden Arbeitsschritten gewonnenen Wissens Entscheidungsgrundlagen und Handlungsempfehlungen für die beteiligten Akteure erarbeitet.
Den deutlichsten Einfluss auf das Unfallrisiko hat der Faktor Dämmerung, während der sich je nach Tierart bis zu zwanzigmal so viele Kollisionen als über vergleichbare Zeitspannen bei Tageslicht ereignen. In der Analyse der jahreszeitlichen Verteilung zeigen sich zudem deutliche Schwerpunkte während der Paarungszeiten und Revierkämpfe. Hinsichtlich der Landschaftsmatrix führen erhöhte Anteile von Landwirtschafts- und Waldflächen nicht zwingend zu der Entstehung von Unfallschwerpunktstrecken, vielmehr muss die individuelle Komposition der Örtlichkeit untersucht werden. Die Nähe von großen Fließgewässern und Seen hingegen bewirkt einen steigernden Einfluss auf die Unfallzahlen. Dichteunterschiede der Wildunfallhäufigkeit je nach Tierart zeigen sich meist nur im größeren Maßstab; im Westen Hessens dominieren Reh-, im Süden Schwarzwildunfälle. Die Unfälle geschehen zu 70 % männlichen Fahrern, insbesondere in den Altersgruppen 20-24 sowie 45-50 Jahren.
Insbesondere der Herbst bietet sich für Warnaktionen an, beispielsweise durch temporär aktivierte LED-Schilder. Bezüglich der effektivsten klassischen Gegenmaßnahme, dem Wildschutzzaun, besteht die Notwendigkeit zu einer besseren Datenhaltung der Behörden sowie einer Novellierung der Richtlinie zu den Einsatzkriterien für und der Konstruktion der Zaunsysteme. Die Prozesslandschaft zeichnet sich dadurch aus, dass die meisten Akteure nur wenig Initiative zeigen und gleichzeitig lediglich geringem Handlungsdruck unterliegen. Es bestehen keine Interessenskonflikte, sondern eher zeigt sich Synergiepotenzial. Zentral ist zuallererst, die hauptsächlich organisatorischen Aufgabenstellungen wie ein übergeordnetes Großprojekt zu starten und eine zentrale Open-Data Meldeplattform einzurichten. Hier sind die Politik und Einrichtungen wie die Bundesanstalt für Straßenwesen gefordert. Nur mit ihrer Initiative können klassische Maßnahmen optimiert, innovative Lösungen in Kooperation mit der Automobilindustrie und IT-Dienstleistern eingeführt und das volle Potenzial der sich aktuell weiterentwickelnden Technologie zur Unfallprävention ausgeschöpft werden.
With the exception of ingredients that may have an allergenic effect, alcoholic beverages with above 1.2% alcohol by volume are currently exempt from mandatory nutrition and ingredient labelling. In 2017, however, the European Commission decided that, in order to protect consumer interests, further exemption from this special regulation could not be justified. Mandatory nutrition and ingredient labelling for wine will affect not only all European producers but also every international producer who exports wine to an EU member state.
Many studies have investigated how consumers behave in relation to nutrition labelling and ingredient listings for food in general, but only a few have considered alcoholic beverages and wine specifically. Existing studies of wine are limited to quantitative approaches that focus on consumers’ stated interests regarding ingredient and nutrition information, utilising the direct elicitation of stated preferences. These methods are prone to greatly overestimate the effect. There is a lack of more indirect observational studies in more realistic settings that analyse consumers’ emotional and verbal reactions when confronted with ingredient and nutrition information on a bottle of wine as well as the implications that this information will have on their choice behaviour. Finally, there is a lack of empirical research on the consequences that mandatory nutrition and ingredient labelling will have for producers.
In order to fill these gaps, the main objectives of this dissertation are the following: First, to analyse consumers’ reactions to nutrition and ingredient labelling covering their emotional reactions and the effect on wine choice and demand as well as the influences of additional information, time and country. Second, to examine the consequences that producers are facing with regard to nutrition and ingredient labelling for wine by analysing producers’ expectations of consumer reactions as well as the effects on production processes and competitive advantages.
A multi-stage multi-method research design, which combined qualitative focus groups and a discrete choice experiment, was utilised to analyse consumers’ reactions to nutrition and ingredient labelling for wine across several countries. In order to analyse the consequences that the potential new EU labelling law will have for wine producers, an exploratory online survey to ask producers directly was utilised.
The results suggest that the wine industry will face considerable challenges once nutrition and ingredient labelling is mandatory. Consumers’ emotional reactions, especially to the ingredients in wine, are rather negative, and they are becoming less likely to view wine as a very natural product. Average wine-involved consumers were shown to place a considerable amount of importance on nutrition information in a retail setting and prefer to receive complete information. Without additional guidance, consumers only place low importance on ingredient information, but this changes when they are negatively confronted with the topic. Negative information has the potential to affect how consumers choose wine by increasing the attention they pay to ingredients, at the cost of the attention directed at sensory descriptions, and by changing consumers’ preferences to shorter ingredient lists. Some consumers in traditional wine markets are even likely to refrain from buying wine in the case of negative media coverage. While consumers will be strongly affected by nutrition and ingredient labelling in the short term, they are likely to adapt to this information in the mid to long term, which will reduce the effect of negative media coverage.
In addition to the effects on consumer behaviour, mandatory nutrition and ingredient labelling will likely also change production processes and competitive advantages within the wine industry. In order to actively avoid declarable substances, some producers will change their oenological practices, which might lead to a deterioration in wine quality and higher wine prices. Providing correct nutrition and ingredient information for each batch will make the labelling process more difficult and more expensive. Although consumers highly value sensory information, this information is likely to be reduced or eliminated when nutrition and ingredient labelling is introduced as the competition for space on back labels will increase. The introduction of mandatory nutrition and ingredient labelling is also likely to affect competitive advantages between wine producers. Producers that are able to and willing to adapt will have the chance to gain competitive advantages.
Overall, producers are advised to adapt their communication strategies to actively promote the reasons for the use of ingredients in wine production in order to reduce the effects of negative media coverage. The industry should also prepare in advance for changes in production processes and potential changes in consumer preferences because mandatory nutrition and ingredient labelling will likely be introduced within the next few years.
Products based on yeasts are a new trend in oenological application. Yeast derived
products (YDPs) are used in any stage of wine making, from the vineyard to the
wine. Most products shall support either the alcoholic or the malolactic fermentation
as nutrient supply. YDPs can also serve as aroma enhancers or fining agents. The
amount of products and applications is permanently increasing and therefore the
demand of a deeper insight into this topic is getting more important. This dissertation
serves as basis for following studies on and characterisation of yeast derived
products. It proves, that the topics to be followed and investigated in the future are
manifold and worth working on.
Already existing analytical methods can be used, sometimes with adoptions.
Standard operation procedures (SOPs) are worked out for future reproducible
analyses. For the most parameters, there are remarkable deviations between the
samples. Only ammonia and the turbidity (NTU) are exceptions. The parameter
“water soluble fraction” has the most important influence. Samples with a high
solubility do show higher contents in most of the parameters compared to samples
with lower solubility (and higher content of soluble matter). This leads to the
conclusion, that there are two groups within the YDPs, depending on their solubility.
These two groups should be kept separately in future data evaluation, interpretation
and calibration of spectroscopic methods. Multi-variate date exploration is highly
effective and revelatory. Outliers can be detected and explained.
The FTIR measurements of the eluates, suspensions and the UV-VIS/NIR
measurement give similar results, supporting, that spectroscopic methods are
powerful tools for YDPs analyses and characterisations. The data pre-treatment of
the spectra is crucial and mandatory, but solutions can be presented.
The calibrations for the different spectroscopic methods are promising. This proves,
that it is worth to keep on working on this field. Only the ATR-FTIR in the set-up of the
apparatus used in this project, shows too many drawbacks. The UV-VIS/NIR
calibrations could be improved by using a device more precise and suitable for the
nature of the samples.
A grouping according to the solubility is the only grouping, that can be done with the
data set of this study. Neither the grouping according the main application, nor the
supplier show a pattern. A separation of oenological and food industry products does not take place. The samples from food industry are highly soluble and can be
separated from the less soluble oenological products. But the soluble oenological
products (yeast extracts, mannoproteins) cannot be separated from food industry
products.
Almost 40% of the world’s terrestrial surface is covered by agriculture. Thus, agricultural land
is of particular importance for the conservation of biodiversity. At the same time, the intensification of management practices and the concomitant homogenization of landscapes are
main drivers for a severe loss of biodiversity. The protection of arthropods in agricultural
landscapes has gained increased attention facing the current biodiversity crisis. In agricultural landscapes, grapevine is a particularly intensively managed crop, which is characterised by frequent application of fungicides. On the other hand, vineyards and especially
the inter-rows between vines with their permanent character can serve as habitats for many
organisms. Additional nesting and feeding resources for beneficial arthropods can be provided. Measures to enhance biodiversity in viticulture mainly encompass organic management and the management of inter-row vegetation cove, for example by tillage regime or the
use of seed mixtures. Little is known about the effectiveness of these measures for the diversity of different species groups, especially in interaction with the surrounding landscape
context.
Within the framework of the presented dissertation, various measures to enhance biodiversity were investigated using different organism groups in vineyards. The main part of
this work is based on a field study in which organic and conventional management were
compared. For this purpose, 15 pairs of organically and conventionally managed vineyards
along a gradient of landscape complexity in Rhinehessen were chosen. The effects of management system, landscape context and inter-row vegetation structure on different species
groups within vineyards were compared. Studied groups included entomopathogenic fungi
in the soil, soil-dwelling spiders and carabid beetles as well as flying, cavity-nesting solitary
bees and wasps. In an additional experiment, four different soil treatments and their effects
on carabid beetles and their weed predation potential were compared in two consecutive
years. Therefore, four experimental plots each were installed in nine additional vineyards in
Rhinehessen. For these vineyards, landscape structure and inter-row vegetation cover was
also characterised.
Overall, each of the investigated species groups benefited from different measures and
landscape or vegetation structure. Organically managed vineyards did not show a general
increase in biodiversity, even though their soils had higher organic matter contents on average and their vegetation cover offered more floral resources. Entomopathogenic fungi were
found to be particularly well adapted to increased copper levels in the soil. Soil copper contents tended to be higher under organic management. Solitary bees and soil-dwelling spiders profited from organic farming. Enhanced landscape complexity, i.e. the connectivity
of semi-natural habitat elements and the area covered by them was particularly beneficial
for solitary bees and spiders. An increasing proportion of area covered by annual crops in
the vicinity of vineyards had a negative effect on carabid beetles and solitary wasps. While
the wasps benefited from dense inter-row vegetation cover, carabid beetles preferred sparse
vegetation cover. Similarly, more intensive tillage regimes did not have a negative effect on
them. It should be emphasized that all the sampled vineyards – whether organically or conventionally managed - hosted species of conservation concern from all investigated groups.
With a diverse mixture of landscape structures as well as a variation of management strategies and soil and vegetation covers within fields, viticultural landscapes can contribute significantly to the protection of agrobiodiversity.
Apple (Malus x domestica Borkh.) is the major tree fruit in Germany, but there still exist major uncertainties in commercial apple production. Thinning has been practiced for many years and is an essential part for successful apple production, but is still an unpredictable part with large variations from year to year and even within years. Another uncertainty for apple growers is the need of apple trees for adequate water supply. Due to the advancing climate change apple growers are uncertain whether additional irrigation will be necessary during the establishment phase of young apple trees.
Therefore, to facilitate these decisions in future, the motivation of this study was to acquire a universal apple model to be used in Germany and Central-Europe. The apple carbon-balance model MaluSim which has been developed in the USA was chosen as a basis. At first, the model has been parameterized for German growing conditions and first simulation runs were conducted. In comparison to the original model, the seasonal assimilate production for German standard trees was about half of the one for standard trees in the USA, while standard trees in Germany were only about one third of the size of US ones.
Subsequently, the previously untested fruit growth and abscission submodel has been modified and tested. Simulated final fruit numbers were compared to counted fruit numbers of unthinned trials in Zornheim (GER), Jork (GER), Lindau (CH), Güttingen (CH) and Wädenswil (CH). The modification ‘G4-4’ showed good simulation results with very low deviations to actual fruit numbers. Average deviation to fruit numbers was only 3.7 %. Results indicate that the model is able to very adequately calculate final fruit numbers of natural fruit drop of Central-European apple trees and that it could be a tool used for thinning advices.
Based on published data, a new water submodel has been included into the MaluSim framework to additionally improve the model. Midday stem water potential has been used as an indicator for water status of the tree. A water stress effect on long shoot growth, respiration, and photosynthesis based on midday stem water potential was used in the water submodel. First simulation runs using the new water submodel indicate that general behavior is realistic. Modeling results generally corresponded to findings of published experimental results. The submodel is able to simulate variable intensities of water deficit effects at variable times.
To study the effects of additional irrigation and water deficits on young apple orchards a field experiment was conducted during 2012 and 2013 in Geisenheim, Germany. Trees of the cultivars ‘Fresco’ (‘Wellant®’), ‘Jugala’, and ‘AW 106’ (‘Sapora®’) were planted in autumn 2011 in a randomized plot design. In 2012, three irrigation treatments, CT (control treatment, only rain fed), NT (normal treatment, irrigated with 2 L/tree/day), and ET (evapotranspiration treatment, irrigation based on calculated water balance), were applied and effects on tree growth and physiology were recorded in 2012 and 2013. Besides soil moisture, water status of the trees has been recorded using predawn and midday stem water potential measurements.
In both years, amounts of precipitation were higher than the 30-year average for the site, with 2013 being wetter than 2012. Between treatments, statistically significant differences developed in both seasons, but were less profound in 2013. In 2012, vegetative growth recorded in NT and ET was statistically significantly higher than in CT for all cultivars. In the wetter season 2013, similar tendencies evolved. But only in ‘Jugala’ and ‘Fresco’ long shoot growth and wood surface area was significantly higher, while for ‘AW 106’ differences in long shoot growth were not statistically significant. Similar results were obtained for the first harvest in 2013.
Light interception and calculated leaf area, measured in ‘Fresco’, was significantly lower in CT trees (2012: 17.4 %; 2013: 24.9 %) compared to ET (2012: 26.3 %; 2013: 42.1 %) and NT (2012: 24.2 %; 2013: 38.3 %), in both years. Additionally, differences between CT and the two irrigated treatments were found for leaf gas exchange rates during the seasons. A relationship between midday stem water potential and leaf gas exchange has been confirmed. Grouping of photosynthesis measurements according to midday stem water potentials led to statistically significant differences between groups. Photosynthesis started to decrease between -1 and -1.5 MPa.
In conclusion, the results show that although both years have even been wetter than usual, the additional irrigation was highly beneficial for tree growth and had a positive effect on orchard establishment. This effect is supposed to be considerably higher in drier years.
Light is one of the most important abiotic factors for plant physiological processes. In addition to light intensity, the spectral quality of light can also influence the plant morphology and the content of secondary metabolites. In the horticultural industry, artificial light is used in to enable year-round production of herbs, ornamental plants and vegetables in winter terms. Until today, discharge lamps like high-pressure sodium (HPS) lamps, emitting predominantly orange and red light and high amounts of infrared radiation, are the most common lamp systems in greenhouses. In the last decades, light-emitting diodes (LEDs) emerged as an efficient alternative light source. LEDs have the advantage of distinct adjustments to the light spectrum. For a usage in horticultural industry LEDs are often too expensive. Furthermore, reduced plant growth can occur due to incorrectly adjusted light spectra and lower leaf temperatures caused by the lack of infrared radiation.
In a research project (LOEWE, funding no. 487/15-29) funded by the Hessen State Ministry of Higher Education, Research and Arts, Microwave plasma lamps (MPL) were tested as new light sources for horticultural industry and plant research. The electrodeless lamp systems emit light in similar properties like sun light. The aim of the study was to determine the influence of artificial sunlight of the MPL on the accumulation of secondary metabolites, plant architecture and plant physiology of three different species (coleus, basil and potted roses). The MPL was compared with other light systems such as commercial HPS lamps, LEDs or ceramic metal halide lamps (CDM). In addition to morphological parameters such as plant height, internode length or fresh and dry weight, the phenolic content of leaves grown under the respective light sources were examined. Overall an increased far-red light content in the emission spectra of the MPL showed high influence on the plant architecture which was observed in all three plant species. Artificial sunlight from MPL induced stem elongation in coleus and basil plants, compared to the other tested light sources. In potted roses a reduced branching degree was observed under MPL light compared to HPS grown plants.
In addition to the impact of far-red light also the blue light content of the emission spectra was found to be a strong influencing factor for plant physiological processes. A positive correlation between blue light content and leaf thickness was determined in coleus cultivated under MPL, LED, HPS and CDM lamps. Low blue light content in HPS emission spectra resulted in shade-adapted leaves with low photosynthetic capacity and susceptibility to high irradiances. Blue light was assumed to increase phenolic metabolites in basil and rose leaves. Furthermore, the different light treatments resulted in an alteration of the composition of essential oils of basil. Experiments with coleus plants demonstrated that besides light color also the infrared radiation, had an influence on secondary metabolites by causing different leaf temperatures. Coleus plants grown with MPL showed the lowest content of phenolic compounds such as rosmarinic acid per dry weight. Infrared radiation resulted in a faster plant development indicated by increased biomass production and higher leaf formation rate as observed in coleus and basil plants.
The results obtained in this study show that the influence of leaf temperature should always be considered when comparing different lamp systems. Especially when LEDs are compared to discharge lamps an overestimation of light color can be a consequence since also infrared radiation influences the content of phenolic compounds and plant growth.