Refine
Departments, institutes and facilities
Document Type
- Article (18)
- Conference Object (7)
- Report (4)
- Book (monograph, edited volume) (1)
- Part of a Book (1)
- Doctoral Thesis (1)
Year of publication
Keywords
- C sequestration (2)
- C source (2)
- Crisis Communication (2)
- Economy (2)
- Issues Monitoring (2)
- N immobilisation (2)
- Quality management (2)
- Social Media Analysis (2)
- Web Data Mining (2)
- citizen participation (2)
Although much effort is made to prevent risks arising from food, food-borne diseases are an ever present-threat to the consumers’ health. The consumption of fresh food that is contaminated with pathogens like fungi, viruses or bacteria can cause food poisoning that leads to severe health damages or even death. The outbreak of Shiga Toxin-producing enterohemorrhagic E. coli (EHEC) in Germany and neighbouring countries in 2011 has shown this dramatically. Nearly 4.000 people were reported of being affected and more than 50 people died during the so called EHEC-crisis. As a result the consumers’ trust in the safety of fruits and vegetables decreased sharply.
Although much effort is made to prevent risks arising from food, food-borne diseases are an ever-present threat to the consumers’ health. The consumption of fresh food that is contaminated with pathogens like fungi, viruses or bacteria can cause food poisoning that leads to severe health damages or even death. The outbreak of Shiga Toxin-producing enterohemorrhagic E. coli (EHEC) in Germany and neighbouring countries in 2011 has shown this dramatically. Nearly 4.000 people were reported of being affected and more than 50 people died during the so called EHEC-crisis. As a result the consumers’ trust in the safety of fruits and vegetables decreased sharply.
An apple a day keeps the doctor away’. While it may be true that a balanced diet is a prerequisite for good health, how good is what we eat and drink every day? And is it actually possible to fulfil every customer desire with the vast array of foodstuffs on offer? BSE, dioxin in eggs, EHEC sprouts: in the light of repeated food safety crises, the issue of quality assurance as well as customer-oriented quality management has become of prime importance for the agri-food industry.
Agricultural activities within the city boundaries have a long history in both developed and developing countries. Especially in developing countries these activities contribute to food security and the mitigation of malnutrition (food grown for home consumption). They generate additional income and contribute to recreation, environmental health as well as social interaction. In this paper, a broad approach of Urban AgriCulture is used, which includes the production of crops in urban and peri-urban areas and ranges in developed countries from allotment gardens (Schrebergarten) over community gardens (Urban Gardening) to semi-entrepreneurial self-harvest farms and fully commercialized agriculture (Urban Farming). Citizens seek to make a shift from traditional to new (sustainable) forms of food supply. From this evolves a demand for urban spaces that can be used agriculturally. The way how these citizens’ initiatives can be supported and their contribution to a resilient and sustainable urban food system increasingly attracts attention. This paper presents an empirical case study on Urban AgriCulture initiatives in the Bonn-Rhein-Sieg region (Germany). Urban AgriCulture is still a niche movement with the potential to contribute more significantly to urban development and constitute a pillar of urban quality of life.
Large sections of the German society are able to buy and consume meat on a daily basis due to progress in the agri-food sector. However, the way meat is produced, traded and consumed increasingly has become an issue that is controversially discussed by the media, non-governmental organisations (NGOs), lobbyists, the industry itself and consumers – often with a negative connotation. The meat industry reacts to this. By creating information campaigns and animal welfare initiatives it aims to stress that it is going to take its corporate social responsibilities (CSR) for consumers and animal welfare seriously. But, the industry’s actions are still criticised as being not sufficient to improve animal welfare levels significantly. Much of this criticism can be observed in online news portals, where articles about the issue get published and commented by readers. This makes online portals a valuable source for information that is to be tapped in this study. It aims to better understand the multifaceted discussions concerning animal welfare initiatives in online portals. By applying qualitative content analysis and web mining techniques to a sample of documents taken from three major German news sites it can be shown that online discussions refer to various aspects of sustainability and corporate social responsibility. Findings also indicate that the discussions are framed by financial aspects.
Agricultural activities within city boundaries have a long history in both developed and developing countries. In this paper, a broad approach to Urban AgriCulture (UAC) is used, one that includes the production of crops in urban and peri-urban areas and ranges in developed countries from allotment gardens over community gardens to semi-entrepreneurial self-harvest farms and fully commercialized agriculture. With an empirical case study on UAC Initiatives in the Bonn/Rhein-Sieg region this work fills a gap since the lack of comprehensive and comparative studies on urban agriculture (UA) currently makes it difficult for researchers to identify the benefits of UA activities.
Food losses occur for many reasons at all stages of supply chains for fruits, vegetables and potatoes. They cause immense economic, environmental and social costs – not only in developing countries but also in developed countries. According to the European Commission, about 90 million tonnes of food are wasted annually in Europe alone. However, particularly for the early stages of supply chains for fruits, vegetables and potatoes there is still a lack of reliable data. Thus, one objective of this study is to contribute to the quantification of food losses between field and retail, where the main focus is set on potatoes, apples, carrots, strawberries and asparagus. Furthermore, neither reasons why products are removed from the supply chains nor their alternative uses are fully examined yet. This is why, the study takes a look on those issues, too. Results are based on data from an online survey among producers of fruits, vegetables and potatoes in North-Rhine Westphalia, Germany and on interviews with producers and other supply chain experts. Findings suggest that the products’ size and form, their storage capabilities and food safety issues have big impacts on food losses. Despite a small sample size, these findings are in line with recent studies.
Chloritesare found in igneous rocks, and more commonly
in sediments and low grade metamorphic rocks (BrinJiey &
Brown 1980). Because chlorites are less stable than most of
the other clay minerals when placed into an acidic
environment (Barnhisel & Bertsch 1989), they play
significant roles in the solution chemistry and may be an
important source of magnesium and micronutrients in soils
(Ross 1975). The objective of the present study was to
compare the weathering behavior of different chlorites in
different chemical environments.
Durch natürliche und anthropogene Säureeinträge sind vor
allem auf naturnahen Standorten Mineleuropas, insbeson-
dere bei Waldböden, schwerwiegende und langfristig wirk-
same negative Veränderungen der Bodeneigenschaften, der
Bodenvegetation und teilweise auch der Qualität des Si-
ckerwassers und der Oberflächengewässer eingetreten
(Veerhoff et al. 1996). Die weitere Bodenentwicklung auf
solchen Standorten wird ganz wesentlich von der SNK und
den H'-Pufferraten der (noch) vorhandenen Bodenminerale
bestimmt. Um Prognosen über die zukünftige Entwicklung
machen zu können, wurden neun für Böden typische Mine-
rale auf ihr Pufferverhalten untersucht.
„from stable to table“
(2008)
Chain models as a tool to quantify the relation between soil, crop quality and human exposure
(2008)
Hinsichtlich der regional hohen N-Eintragungsmengen durch die Landwirtschaft sowie der bevorstehenden erneuten Verschärfung der Düngeverordnung, ist die Kenntnis über die Dynamik der N-Mineralisierung verschiedener Wirtschaftsdünger unerlässlich. Insbesondere bei der Etablierung neuartiger organischer N-Dünger ist deren Umweltwirkung, namentlich die der reaktiven Stickstoffverbindungen, von größter Relevanz. Damit zukünftig kosten- und zeitintensive destruktive Bonituren durch nicht invasive ersetzt werden können, bedarf es der Erprobung und Validierung der sensorbasierten Methodik. Dazu werden im Rahmen des INTERREG-Projektes „food pro.tec.ts“ verschiedene Wirtschaftsdünger, vor allem aus Miscanthus-Häckselgut, in einem Feldversuch mit Wintergerste appliziert und die N-Aufnahmemenge erfasst. Eine einmalige Hyperspektralmessung im Wellenlängenbereich von 500 nm bis 900 nm, mittels einer Drohne zum Zeitpunkt der Vollreife, dokumentiert den Zustand des Bestandes. Mithilfe zweier Indizes lassen sich kurz vor der Ernte noch Unterschiede zwischen einigen Varianten erkennen und auf den N-Versorgungszustand schließen.
Sustainable urban soil management is becoming increasingly crucial due to its vital role in climate and water regulation and its significant potential for storing soil organic carbon (SOC). This significance is emphasized considering the ongoing urbanization and climate change issues. Although SOC is influenced by many factors, such as soil type and climate fluctuations (temperature, precipitation patterns), on a regional scale, land use and management practices (e.g., fertilization, irrigation) can have a more significant impact on SOC storage and the balance of soil-atmosphere carbon fluxes. However, there is still a limited understanding of the amount of humus content in urban soils and the effects of urban development and management practices on soil health and carbon storage. We investigated how management practices in urban green spaces influence soil carbon storage as the primary indicator of soil health.
The present study was carried out in the Bonn-Rhein-Sieg area, as the region is vital in terms of sustainable urban and regional development with a high population density (Rhein-Sieg district: 338.4, Bonn: 520.9 inhabitants/km2) in Germany. A survey was conducted with owners and managers of urban private (e.g., allotment and backyard garden) and public green spaces on the practices for the most common vegetation types (e.g., lawn, vegetable, ornamental). In the autumn and winter of 2022, 248 soil samples (0–20 cm depth) were collected from 95 private and public green spaces in the study area and analyzed for physiochemical and biological properties. Multivariate Analysis of Variance (MANOVA) was performed to assess the effects of different management practices on soil properties.
Our results indicate that the average SOC stock in public green areas (94.67 Mg ha-1) is substantially higher than in private ones (house garden 67.72 Mg ha-1, allotment garden 73.15 Mg ha-1). Moreover, urban green spaces with vegetables (91.66 Mg ha-1) and ornamentals (85.05 mg ha-1) show greater SOC stock levels when comparing vegetation types (lawn 62.48 Mg ha-1). Significant differences in SOC are also found for various management practices. Specifically, the monthly fertilization schedule resulted in higher SOC levels (127.37 Mg ha⁻¹) compared to the yearly fertilization schedule (76.88 Mg ha⁻¹). Additionally, the use of organic fertilizers contributed to increased SOC levels (84.40 Mg ha⁻¹) in contrast to mineral fertilizer applications (65.31 Mg ha⁻¹). The average SOC stock in all the studied urban green spaces (85 mg ha-1) was higher than the average SOC stock in arable soils in Germany (47.30 Mg ha-1). The higher SOC in the region could be due to vegetation types and fertilization frequencies, which show statistically significant effects (p-value <0.001). Other management practices (e.g., irrigation type and frequency) did not show a significant effect. Our findings highlight the significance of soil management practices, particularly in selecting vegetation types and determining fertilization frequency, as essential factors influencing urban SOC.
Der zunehmende Wunsch der Verbraucher nach einem natürlichen Lebensstil führt unter anderem zu einem erhöhten Konsum von Rohmilch und Milchprodukten aus unpasteurisierter Milch (Hudopisk et al., 2013). Rohmilchkonsumenten bevorzugen Rohmilch zum Einen wegen des subjektiven Eindrucks eines besseren Geschmacks und zum Anderen versprechen sie sich gesundheitliche Vorteile, wie eine reduzierte Empfindlichkeit gegen Allergien und eine bessere Qualität der enthaltenen Nährstoffe, durch den Verzehr unbehandelter Milch (Claeys et al., 2014). Mit dem Konsum von Rohmilch gehen allerdings mikrobiologische Risiken einher, da Rohmilch aufgrund ihres neutralen pH-Wertes, dem hohen Nährstoffgehalt und der hohen Wasseraktivität einen guten Nährboden für mikrobielles Wachstum darstellt. Das Wachstum von verschiedenen Mikroorganismen wird dabei größtenteils durch die Temperatur, die kompetitive Begleitflora und die Anwesenheit von Hemmstoffen beeinflusst (Claeys et al., 2013).Mögliche Kontaminationen der Rohmilch resultieren entweder aus einer direkten Abgabe von Mikroorganismen durch das Euter, als Konsequenz von Entzündungen oder durch eine indirekte Kontamination während des Melkvorgangs oder der späteren Handhabung (EFSA, 2015).
Der vorliegende Fachbericht ist der Abschlussbericht eines im Auftrag des Ministeriums für Umwelt, Landwirtschaft, Natur- und Verbraucherschutz durchgeführten Kooperationsprojekts des LANUV mit dem Internationalen Zentrum für Nachhaltige Entwicklung (Hochschule-Bonn-Rhein-Sieg) zur Untersuchung von Mengen und Gründen für die Entstehung von Lebensmittelverlusten bei Obst, Gemüse und Kartoffeln sowie zur Entwicklung von Vermeidungsstrategien im Winter 2016/2017.
Cultivation of Miscanthus x giganteus L. (Mis) with annual harvest of biomass could provide an additional C source for farmers. To test the potential of Mis-C for immobilizing inorganic N from slurry or manure and as a C source for soil organic matter build-up in comparison to wheat (Triticum aestivum L.) straw (WS), a greenhouse experiment was performed. Pot experiments with ryegrass (Lolium perenne L.) were set up to investigate the N dynamics of two organic fertilisers based on Mis at Campus Klein-Altendorf, Germany. The two fertilisers, a mixture of cattle slurry and Mis as well as cattle manure from Mis-bedding material resulted in a slightly higher N immobilisation. Especially at the 1st and 2nd harvest, they were partly significantly different compared with the WS treatments. The fertilisers based on Mis resulted in a slightly higher microbial biomass C and microbial biomass N and thus can be identified as an additional C source to prevent nitrogen losses and for the build-up of soil organic matter (SOM) in the long-term.
Erfassung der N-Dynamik verschiedener Wirtschaftsdünger in Wintergerste und Senf im Dürrejahr 2018
(2019)
Soil nutrient depletion threatens global food security and has been seriously underestimated for potassium (K) and several micronutrients. This is particularly the case for highly weathered soils in tropical countries, where classical soluble fertilizers are often not affordable or not accessible. One way to replenish macro- and micronutrients are ground silicate rock powders (SRPs). Rock forming silicate minerals contain most nutrients essential for higher plants, yet slow and inconsistent weathering rates have restricted their use in the past. Recent findings, however, challenge past agronomic objections which insufficiently addressed the factorial complexity of the weathering process. This review therefore first presents a framework with the most relevant factors for the weathering of SRPs through which several outcomes of prior studies can be explained. A subsequent analysis of 48 crop trials reveals the potential as alternative K source and multi-nutrient soil amendment for tropical soils, whereas the benefits for temperate soils are currently inconclusive. Beneficial results prevail for mafic and ultramafic rocks like basalts and rocks containing nepheline or glauconite. Several rock modifications are highly efficient in increasing the agronomic effectiveness of SRPs. Enhanced weathering of SRPs could additionally sequester substantial amounts of CO2 from the atmosphere and silicon (Si) supply can induce a broad spectrum of plant biotic and abiotic stress resistance. Recycling massive amounts of rock residues from domestic mining industries could furthermore resolve serious disposal challenges and improve fertilizer self-sufficiency. In conclusion, under the right circumstances, SRPs could not only advance low-cost and regional soil sustaining crop production but contribute to various sustainable development goals.
For several decades, farmers have been mixing rock powders with livestock slurry to reduce its NH3 emissions and increase its nutrient content. However, mixing rock powders with slurry is controversial, and there is currently no scientific evidence for its effects on NH3 and greenhouse gas (GHG) emissions or on changes in its nutrient content due to element release from rock powders. The major aim of this study was therefore to analyse the effects of mixing two commercially established rock powders with cattle slurry on NH3, CO2, N2O and CH4 emissions, and on nutrient release over a course of 46 days. We found that rock powders did not significantly affect CO2 emission rates. NH3 and N2O emission rates did not differ significantly up until the end of the trial, when the emission rates of the rock powder treatments significantly increased for NH3 and significantly decreased for N2O, respectively, which coincided with a reduction of the slurry crust. Cumulative NH3 emissions did not, however, differ significantly between treatments. Unexpected and significant increases in CH4 emission rates occurred for the rock powder treatments. Rock powders increased the macro- and micronutrient content of the slurry. The conflicting results are discussed and future research directions are proposed.
Cultivation of perennials such as Miscanthus x giganteus Greef et Deuter (Mis) combines the provision of ecosystem services and the generation of additional carbon sources for farming. The potential of Mis based fertilisers, regarding immobilisation of inorganic nitrogen (N) and build-up of soil organic matter (SOM), was tested in a field trial. Therefore, a crop rotation of winter barley (Hordeum vulgare L.), mustard (Sinapis alba L.) as catch crop, sugar beet (Beta vulgaris L.) and winter wheat (Triticum aestivum L.) was set up. The tested treatments were a mixture of Cattle Slurry (CS) and Mis, a mixture of CS and Wheat Straw (CS–WS), Cattle Manure (CM) from Mis shredded bedding, CM from WS shredded bedding, a pure CS, Urea Ammonium Nitrate (UAN) and a treatment without any N applied (NoN). When the carbon-rich fertilisers (both mixtures and manures) were applied to cereals, they led to a slight N immobilisation compared to pure CS, whereas differences were mostly not significant. Furthermore, Mis fertilisers were at least as efficient as WS-based organic fertilisers in inducing a contribution of SOM build-up and in reducing inorganic N before winter and thus preventing N losses, whereas differences were mostly not significant.