Open Access

Irrigation is often celebrated as a means of intensifying agricultural production and improving food and nutrition security. In the context of semi-subsistence smallholder agriculture irrigation can have a positive impact on dietary diversity through various pathways. However, studies on the linkages between irrigation and rural household nutrition show mixed results. This study argues that irrigation is not a simple agricultural input factor but is embedded in socio-technical conditions. It compares two different irrigation arrangements to understand how irrigation can contribute to transforming local food systems through different pathways. The impact of irrigation on dietary diversity and the potential impact pathways (agricultural income, production diversity and women’s empowerment) are analyzed using a propensity score matching (PSM) approach. The analysis is repeated for subsets of farmer-led and public irrigation to explore how different irrigation arrangements lead to different outcomes. The results show that both farmer-led and public irrigation have a positive impact on agricultural income and dietary diversity. The positive effect on dietary diversity was stronger in farmer-led irrigation while the income effect was stronger in public irrigation arrangement. However, the positive impact on dietary diversity appears to be dampened by a reduction in production diversity, particularly in the case of public irrigation. This study highlights that irrigation development may lead to a more diverse diet, strengthen the income pathway but weaken the production diversity pathway with the extent of this effect depending on the irrigation arrangement. Therefore, policy makers should be aware of this trade-off and seek to support irrigation that allows increased production for urban markets without compromising the dietary intake of rural households.

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.

In the upcoming decades, urban areas are expected to undergo significant expansion and transformation in order to accommodate the growing proportion of the world's population living in cities. This challenge presents a unique opportunity to rethink our cities and to shift from development patterns that have resulted in urban environments associated with environmental degradation and disconnection to nature and instead embrace transformative changes that promote healthier and more resilient cities where people and nature thrive. Urban green infrastructure is one of the main strategies to achieve this goal, given the potential of various types of green spaces and structures for delivering several ecosystem services benefitting not only human health and wellbeing but also biodiversity conservation. However, limited knowledge remains on the quality necessary to effectively provide the range of benefits expected by green infrastructure and also on possible trade-offs among beneficiaries with different needs. This doctoral thesis addressed these research gaps through two main questions: a) which and how green spaces characteristics are associated with mental health and wellbeing and wildlife support outcomes, and b) what are the synergies and trade-offs between human health and wildlife dimensions in urban green spaces. Through a systematic review, green space features that reportedly affected human mental health or wildlife support in previous studies were compiled. Then, the holistic One Health approach was used as a basis for the development of a framework connecting quality attributes of green spaces with human mental health and wellbeing and wildlife support in the urban context. To apply this framework in a case study in Brazil, the first step required a cross-cultural adaptation of the selected psychometric scales for measuring psychological restoration in the target population. Specifically, the Perceived Restorativeness Scale and the Restoration Outcomes Scale were translated into Portuguese and validated using samples from Porto Alegre and São Paulo cities located in southern and southeastern Brazil. The psychometric properties of both scales presented adequate internal consistency and model fit indexes, which remained consistent across participants’ gender and city of residency. Besides the intended application in this doctoral study, the provision of these newly-validated versions of such measures creates opportunity for the expansion of research on restorative environments in the poorly studied Global South, particularly in Brazil. In São Paulo, Brazil, a case study was carried out utilizing indicators and metrics identified in the systematic review to analyze the relationships outlined in the developed framework. The primary factors affecting user restorativeness were perceived safety and naturalness of parks. These perceptions were associated with park characteristics such as tree canopy coverage, presence of water bodies, and signs of vandalism. The presence of natural water bodies presented a clear mutual benefit for psychological restoration and support to birds (as representative of wildlife species). In contrast, whereas parks with higher tree canopy coverage offered greater potential for restoration to users, outcomes for bird assemblages were distinct depending on the metric selected. Summing up, the findings point out the necessity of a heterogeneous network of green spaces that are purposely planned and managed considering the synergies and trade-offs between human and wildlife requirements. In conclusion, the results of this doctoral thesis confirm the important role of green space quality in providing benefits to humans and animals. It also stresses the advantage of applying the One Health approach also to the urban context and, more specifically, to green infrastructure, enabling the identification of mutually beneficial effects and potential trade-offs between the environment, humans, and animals, and ultimately the implementation of truly multifunctional spaces and solutions.

Lignin ist ein aromatisches Biopolymer, das in den Zellwänden von Pflanzen vorkommt. Es ist hauptsächlich aus drei sogenannten Monolignolen (p-Hydroxyphenyl (H), Guajakol (G) und Syringol (S)) aufgebaut, die über verschiedene Bindungen miteinander verknüpft sein können, und enthält eine Vielzahl an funktionellen Gruppen. Interessant für die Verwendung von Lignin sind dabei insbesondere die vielen phenolischen Hydroxygruppen, die als Ausgangsstoff bei der Synthese neuer Produkte dienen können, daneben aber auch für seine antioxidativen Eigenschaften verantwortlich sind. Da Struktur und Eigenschaften von vielen Faktoren wie Biomasse und Aufschlussprozess abhängen, ist eine detaillierte Charakterisierung der Lignine nötig, um Struktur-Eigenschafts-Beziehungen aufzuklären und so einen Schritt näher an eine mögliche stoffliche Nutzung zu kommen. Mit dieser Arbeit soll der Einfluss der Biomasse inklusive der verwendeten Partikelgröße sowie des Organosolv-Aufschlussprozesses auf die Monomerzusammensetzung, das Molekulargewicht und die Antioxidanz der isolierten Lignine untersucht werden. Als Rohstoffe zur Ligningewinnung dienen die drei mehrjährigen lignocellulosereichen Low-Input-Pflanzen Miscanthus x giganteus, Silphium perfoliatum und Paulownia tomentosa, die momentan hauptsächlich zur Energiegewinnung genutzt werden. Im Rahmen der Bioökonomiestrategie der Europäischen Union soll der Schwerpunkt zukünftiger Bioraffinerien jedoch auf eine ganzheitliche Nutzung von Biomassen gelegt und so auch die stoffliche Nutzung fokussiert werden. Zusätzlich zu diesen drei Pflanzen werden auch Organosolv-Lignine aus den in der Literatur bereits gut beschriebenen Biomassen Weizenstroh und Buchenholz isoliert, und zwei Nadelholz-Kraft-Lignine als Vergleich herangezogen. Die Ergebnisse zeigen, dass die Art der Biomasse hauptsächlich die Monomerzusammensetzung beeinflusst: Gräser bestehen aus allen drei Monolignolen, Laubhölzer mehrheitlich aus S- und G-Einheiten, während Nadelhölzer nur aus G-Einheiten aufgebaut sind. Die Holzlignine besitzen zudem höhere Molekulargewichte sowie bessere antioxidative Eigenschaften als die Gras- und Krautlignine. Mit der feineren Vermahlung der Biomasse kann die Monomerzusammensetzung beeinflusst werden: der Einsatz kleinerer Partikelgrößen führt zu Ligninen mit einem höheren Gehalt an H-Einheiten, sowohl für Miscanthus als auch für Paulownia. Außerdem kann bei Paulownia die Ausbeute gesteigert und eine Zunahme des Molekulargewichtes beobachtet werden, wenn die kleinste Siebfraktion für den Organosolv-Aufschluss verwendet wird. Einen größeren Einfluss als der Mahlgrad der Biomasse haben die Autohydrolyse sowie der Organosolv-Aufschlussprozess selbst. Die Monomerzusammensetzung ändert sich aufgrund derselben Biomasse zwar kaum, die Bindungstypen zwischen den Monolignolen dagegen schon. Mit höherer Prozessstärke (Zeit, Temperatur, Ethanol-Konzentration) werden Etherbindungen gespalten, was den Anteil an phenolischen Hydroxygruppen und somit die Antioxidanz erhöht. Neben dieser Depolymerisation werden partiell auch Rekondensationsreaktionen beobachtet. Die erzielten Ergebnisse liefern einen Beitrag zum Verständnis des Zusammenhangs zwischen Ligninquelle und -gewinnung mit der daraus resultierenden Ligninstruktur und Antioxidanz und bieten damit eine Grundlage für den Wandel von der energetischen hin zu einer nachhaltigen stofflichen Nutzung dieses nachwachsenden Biopolymers. Gerade über die Wahl der Aufschlussparameter können Struktur und Antioxidanz gezielt beeinflusst werden, was in zukünftigen Studien weiter fokussiert werden sollte.

The aim of this paper is to assess the objectives of farmers’ challenges in enhancing biodiversity. The so-called “trilemma” (WBGU 2021) of land use stems from the multiple demands made on land for the benefit of mitigating climate change, securing food and maintaining biodiversity. The agricultural sector is accused of maladministration: it is blamed for causing soil contamination, animal cruelty, bee mortality and climate change. That is why farmers are seen as key actors at all levels. They are, however, also key players when it comes to overcoming the problems of the future. Their supportive role is urgently needed, but farmers find themselves caught between a “rock” and a ”hard place”. Consumers are calling for sustainable, environmentally friendly production and inexpensive food products that do not contain pesticide residues, demanding enough food for all. Farmers are restricted by the wants and needs of consumers who are influenced by interest groups and are exposed to direct and indirect influencing factors and their interdependencies. They are also tasked with balancing the scrutiny of the critical public on the one hand, and the control exercised by eager authorities on the other. As part of the DINA (Diversity of Insects in Nature protected Areas) project, a trans- and interdisciplinary research study, we collected and surveyed the data of farmers who are farming within or close to the 21 selected nature protected areas included in the DINA project. Data was collected as part of a mixed method approach using a semi-structured questionnaire. The methodological and strategic approach and interdependencies of issues demonstrate the complexity of today’s problems. To investigate this, we first used the data collection method using questionnaires with closed and open questions. The conflicts and obstacles farmers face were evaluated, and the results show farmers’ willingness and the importance of appreciation shown to farmers for implementation of biodiversity measures. The paper proposes some follow-up activities (quantitative study) to verify the objectives. The results will later lead to recommendations for policymakers and farmers in all German nature protected areas.

Typically, plastic packaging materials are produced using additives, like e.g. stabilisers, to introduce specific desired properties into the material or, in case of stabilisers, to prolong the shelf life of such packaging materials. However, those stabilisers are typically fossil-based and can pose risks to both environmental and human health. Therefore, the present study presents more sustainable alternatives based on regional renewable resources which show the relevant antioxidant, antimicrobial and UV absorbing properties to successfully serve as a plastic stabiliser. In the study, all plants are extracted and characterised with regard to not only antioxidant, antimicrobial and UV absorbing effects, but also with regard to additional relevant information like chemical constituents, molar mass distribution, absorbance in the visible range et cetera. The extraction process is furthermore optimised and, where applicable, reasonable opportunities for waste valorisation are explored and analysed. Furthermore, interactions between analysed plant extracts are described and model films based on Poly-Lactic Acid are prepared, incorporating analysed plant extracts. Based on those model films, formulation tests and migration analysis according to EU legislation is conducted. The well-known aromatic and medicinal plant thyme (Thymus vulgaris L.) includes phenolic terpenoids like thymol and carvacrol which have strong antioxidant, antimicrobial and UV absorbing effects. Analyses show that those effects can be used in both lipophilic and hydrophilic surroundings, that the variant Varico 3 is a more potent cultivar than other analysed thyme variants, and that a passive extraction setup can be used for extract preparation while distillation of the Essential Oils can be a more efficient approach. Macromolecular antioxidant polyphenols, particularly proanthocyanidins, have been found in the seed coats of the European horse chestnut (Aesculus hippocastanum L.) which are regularly discarded in phytopharmaceutical industry. In this study, such effects and compounds have been reported for the first time while a valorisation of waste materials has been analysed successfully. Furthermore, a passive extraction setup for waste materials and whole seeds has been developed. In extracts of snowdrops, precisely Galanthus elwesii HOOK.F., high concentrations of tocopherol have been found which promote a particularly high antioxidant capacity in lipophilic surroundings. Different coniferous woods (Abies div., Picea div.) which are in use as Christmas trees are extracted after separating the biomass in leafs and wood parts before being analysed regarding extraction optimisation and drought resistance of active substances. Antioxidant and UV absorbing proanthocyanidins are found even in dried biomasses, allowing the circular use of already used Christmas trees as bio-based stabilisers and the production of sustainable paper as a byproduct.

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.

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.

Bedingt durch die zunehmende Rohstoffknappheit rückt die Suche nach alternativen, nachhaltigen Rohstoffen immer mehr in den Vordergrund. Im Hinblick auf effiziente chemische Verwertbarkeit bietet Lignin zahlreiche Vorteile für verschiedene Anwendungsbereiche, beispielsweise für biobasierte Polyurethanbeschichtungen, etwa zum Korrosionsschutz. Wesentliche Probleme bei der Verwendung von Lignin ergeben sich durch die Heterogenität dieses Naturstoffes sowie durch dessen geringe Polymerisations-Kompatibilität mit Polyolefinen; beide Faktoren beeinflussen u. a die mechanischen Eigenschaften entsprechender Lignin-basierter Polymere. Zudem hängt die konkrete Struktur und damit auch die physikalisch/chemischen Eigenschaften des Lignins stark von der jeweiligen Rohstoffquelle sowie dem Extraktionsverfahren ab. Ziel dieser Arbeit war die Strukturaufklärung unmodifizierter und modifizierter Kraft-Lignine (KL) und die Untersuchung der Reaktivität aromatischer wie aliphatischer Hydroxygruppen in Abhängigkeit vom pH-Wert. Hierzu wurden unmodifizierte KL aus Schwarzlauge extrahiert und nachfolgend zunächst einer Soxhlet-Extraktion unterzogen, um in Methyltetrahydrofuran lösliche Lignin-Bestandteile – vornehmlich mit aromatischem Charakter – zu gewinnen und so eine verbesserte Löslichkeit auch im bei der nachfolgenden Polyurethansynthese als Lösemittel verwendeten THF zu gewährleisten. Überdies wurden die extrahierten KL via Demethylierung von Methoxygruppen chemisch modifiziert. Zudem wurde mittels nasschemischer Methoden sowie mit differentieller UV/VIS-Spektroskopie die Anzahl an für die Polymerisation erforderliche Hydroxygruppen quantifiziert. Im Anschluss erfolgte, unter besonderer Berücksichtigung ökologischer und ökonomischer Nachhaltigkeitsaspekte, die Synthese Lignin-basierter und funktionalisierter Polyurethanbeschichtungen. Die Oberflächenfunktionalisierung gestattete die Verbesserung der Oberflächenhomogenität sowie - via blend formation - das Einbetten von TPM-Farbstoffen in die Coatings. Hinsichtlich des Einflusses des bei der Extraktion gewählten pH-Wertes (pH = 2 - 5) auf das Verhalten der so gewonnenen KL wurde eine Veränderung sowohl der Struktur der Lignine als auch deren thermischer Stabilität beobachtet. Zudem wurde nachgewiesen, dass mit steigendem pH-Wert die Funktionalität/Reaktivität der aromatischen wie aliphatischen Hydroxygruppen im Lignin zunimmt. Aus unmodifiziertem KL wurden erfolgreich homogene Lignin-basierte Polyurethan-Coatings (LPU-Coatings) synthetisiert; diese LPU-Coatings zeigten bei Verwendung von bei höheren pH-Werten extrahierten KL homogenere, hydrophobe Oberflächenbeschaffenheit sowie gute thermische Stabilität. Zusätzliche Modifizierung der KL durch Demethylierung führte wegen der gesteigerten Anzahl freier Hydroxygruppen zu moderater Reaktivitätssteigerung und damit zu weiterer Verbesserung der Oberflächeneigenschaften hinsichtlich einer homogenen Oberflächenstruktur und -brillanz. Im Hinblick auf den Aspekt der Nachhaltigkeit wurden durch Syntheseoptimierung - bestehend aus Einstellung der Rohstoff-Korngröße, Ultraschallbehandlung und Verwendung des kommerziellen trifunktionellen Polyetherpolyols Lupranol® 3300 in Kombination mit Desmodur® L75 - die Löslichkeit von Lignin im Polyol sowie die thermische Stabilität der LPU-Coatings erhöht. Im Zuge der Syntheseoptimierungen konnte durch verkürzte Trocknungszeiten Energieeinsparung erzielt werden; zudem ließen sich dabei die eingesetzten Mengen kommerziell erhältlicher Chemikalien verringern; beide Einsparungen führten zu Kostenreduktion. Zugleich ließ sich so nicht nur der KL-Anteil im Polymer-Coating erhöhen: Durch eine optimierte wirtschaftliche Einstufensynthese ließ sich die Umsetzung dieser Vorgehensweise auch im Rahmen industrieller Anwendungen vereinfachen. Das Einbetten ausgewählter TPM-Farbstoffe (Kristallviolett und Brilliantgrün) in die LPU-Coatings durch blend formation führte nachweislich zu antimikrobieller Wirkung der Oberflächenbeschichtung, ohne dass die Oberflächenbeschaffenheit an Homogenität verlor. Die im Rahmen dieser Arbeit synthetisierten LPU-Coatings könnten zukünftig als Korrosionsschutz- und antimikrobielle-Beschichtungen ihre Anwendung finden, z. B. in der Landwirtschaft und im Bausektor. Die im Rahmen der vorliegenden Arbeit gewonnen Erkenntnisse liefern einen Beitrag zur strukturellen Aufklärung des komplexen Biopolymers Lignin. Darüber hinaus stellen die Untersuchungen und Ergebnisse eine Grundlage für eine nachhaltige Herstellung von Lignin-basierten Polymerbeschichtungen dar, die in Zukunft immer mehr an Bedeutung gewinnen werden.

In January 2015, German retail and industry jointly started a sector-wide initiative ("Initiative Tierwohl" - ITW) to improve animal welfare standards. The principle of the ITW is communicated mostly via the websites of ITW and its participating companies. However, uncertainty remained whether or not these websites provide the necessary information consumers need on the ITW products. Based on Schwartz's basic human values, different types of consumers were identified by a cluster analysis (ward-method, k-means). The results showed that depending on expressed meta‐values (Self-Transcendence/Openness to Change Self-Enhancement or Conservation), respondents had different specific information sources and needs. Online sources were rarely mentioned, the majority of consumers referred to brochures, flyers and interpersonal contacts.

Argentina substantially contributes to the global organic agriculture and food sector due to its large areas of organically managed agricultural land. However, most of the organic production is intended for export. Overall, food supply for the domestic organic market is hardly tapped. Based on this, we investigate the current importance of organic agriculture and food production as well as consumption attitudes and behavior within the country. The novelty of the study also lies in the observation, documentation and analysis of latest stakeholder‐driven developments towards organic agriculture and food. Furthermore, the publication allows the Argentinean organic market to be significantly more visible for the international audience.

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.

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.

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.