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Methane is a key target for climate change mitigation efforts. With a radiative forcing 85 times stronger than CO₂ over a 20-year period and an atmospheric lifespan of only a decade, mitigating methane emissions will slow climate change in the near-term. However, quantifying methane emissions from specific sectors accurately poses a significant challenge. This is because top-down estimations of methane emissions demand precise observations and constraints on a range of physical and chemical processes. In this thesis, I seek to enhance the accuracy of methane emissions calculations by resolving these processes in detail and advocating for an expansion of the methane monitoring network. The primary mechanism for atmospheric methane destruction is its oxidation by the Hydroxyl radical (OH). Chemical feedbacks due to temporal variations in OH availability can substantially influence the methane lifetime and, consequently, emissions trends over recent decades. In Chapter 2, I quantify the impact of this predominant chemical loss mechanism on methane emissions calculations. Methane loss to the stratosphere represents the second most significant methane destruction mechanism, although the processes involved remain highly uncertain. Accurately quantifying methane loss via stratospheric-tropospheric exchange is crucial for improving the accuracy of methane emissions calculations. In Chapter 3, I utilize chemical tracers to determine how stratospheric-tropospheric exchange influences global methane emissions trends. Current understanding of greenhouse gas fluxes from a top-down perspective typically relies on atmospheric inversions, which depend on spatial and temporal gradients in observed greenhouse gas concentrations. However, maintaining highly accurate ground-based measurements poses logistical and financial challenges, while satellites currently do not provide the requisite accuracy and spatial resolution for long-term monitoring. In Chapter 4, I explore the potential of frequency combs in measuring environmental impacts on greenhouse gas sensing and as tools to expand the observation network. In summary, this thesis contributes to a more profound understanding of the two primary methane sinks and how their variations affect methane emissions trends over recent decades. It also lays the groundwork for the next-generation greenhouse gas observation network using laser frequency combs by quantifying environmental impacts on greenhouse gas spectroscopy directly in the field. Future advances should focus on a more accurate understanding of methane sink processes, improved spectroscopy, and expanded measurement networks. This will require advances in both modeling and measurements. Ultimately, rapid and efficient mitigation of methane emissions remains the most feasible approach to curb anthropogenic climate change. To do this however, accurate assessments of methane trends and emissions necessitate bringing methane measurements and modeling of methane destruction processes closer to the real world.

The land area of the Earth greatly influences climate dynamics through biogeophysical and biogeochemical processes. These processes concern, respectively, the exchange of energy and water, and the exchange of greenhouse gasses (GHGs) such as CO2, CH4 and N2O, between land systems and the atmosphere. By using the Earth’s land surface, humans have greatly altered it – leading to significant environmental impacts. Historically, climate change has mostly been caused by fossil fuel combustion. Land use, land-use change and forestry (LULUCF) have caused an estimated 34% of cumulative anthropogenic CO¬2 emissions since 1750. At the same time, agriculture is responsible for about 13% of global GHG emissions in the form of non-CO2 GHG emissions. The importance of land and land use in climate dynamics means that land has a role in preventing dangerous climate change. First, it is essential to significantly reduce the 23% of annual GHG emissions from the agriculture, forestry and other land use (AFOLU) sector to make ambitious climate targets feasible. Second, land is key to various techniques to remove carbon from the atmosphere (so-called negative emissions or carbon dioxide removal (CDR)). In this thesis, a large portfolio of land-based mitigation measures is assessed in the context of different land-use futures. In addition, detailed analysis are provided on two key land-based mitigation measures: afforestation, and peatland protection and restoration. In addition to climate, land is central to many other sustainable development issues and environmental challenges. For example, it is essential for the provision of resources such as food, energy and water, as well as to sustain terrestrial biodiversity, as also recognized in the Sustainable Development Goals and the planetary boundaries. A useful approach to study different dimensions of sustainable development and environmental change is the nexus concept which recognizes that components of a system are inherently interconnected and must be investigated and managed in an integrated, holistic manner. In this thesis, the water-land-energy-food-climate (WLEFC) nexus is addressed, taking into account trade-offs and synergies between these different systems in achieving multiple goals. Scenario analysis can be used to explore the role of land use in climate change and climate change mitigation, and for other societal goals related to the WLEFC nexus. An important ambition of the scientific community is to develop scenarios that achieve both climate and other environmental and sustainability goals such as the PBs and the SDGs. In this thesis, we use exploratory scenarios that investigate how the future might develop under pre-defined assumptions, as well as normative scenarios that aim for pre-defined targets and describe pathways that could achieve these goals. Examples of targets are stabilizing global warming, nature protection or limits to water extraction. These scenarios are developed using the IMAGE integrated assessment model framework.

Klimawandel und Biodiversitätsverlust sowie Verstädterung und demografischer Wandel haben tiefgreifende Auswirkungen auf Städte und ihre Ökosysteme und damit auf die Lebensbedingungen der Mehrheit der Menschheit. Die Geschwindigkeit des Wandels und die Dringlichkeit der Folgen macht Umweltmonitoring zu einem potentiell interessanten Tool für nachhaltige und resiliente Stadtentwicklung. Der erste Artikel gibt einen Überblick über den aktuellen Stand der Fernerkundung in Bezug auf Stadtökologie und zeigt, dass Fernerkundung relevant für nachhaltige Stadtplanung ist. Es bestehen jedoch bestehen Mängel, da viele Studien nicht direkt umsetzbar sind. Der zweite Artikel zeigt, dass eine wachsende Stadt Möglichkeiten für den Ausbau der grünen Infrastruktur bieten kann. Im dritten Artikel wird untersucht, wie sich die städtische Dichte auf die Bereitstellung von Ökosystemdienstleistungen der grünen Infrastruktur auswirkt. Es wird gezeigt, dass eine hohe Siedlungsdichte nicht zwangsläufig zu einem geringeren Biodiversitätspotenzial oder einer geringeren Kühlkapazität führt. Allerdings sind dicht bebaute Gebiete mit geringer Vegetationsbedeckung besonders auf grüne Infrastruktur angewiesen. Der vierte Artikel befasst sich mit der Frage, wie naturbasierte Lösungen durch eine bessere Vernetzung der Beteiligten gestärkt werden können. Auf der Grundlage einer gezielten Literaturrecherche über Informationstechnologie zur Unterstützung sozial-ökologischer Systeme wird ein Instrument zur Entscheidungshilfe entwickelt. Dieses kombiniert ökologische und soziale Indikatoren, um Klimawandeladaption in Übereinstimmung mit den sozio-ökologischen Bedingungen entwickeln zu können. Der fünfte Artikel bietet eine grundsätzliche Perspektive zur Unterstützung der städtischen Nachhaltigkeit, die auf dem ökologischen-Trait Konzept basiert. Zusammen bieten die fünf Artikel Wege für die Fernerkundungswissenschaft und die angewandte Raumplanung für nachhaltige und resiliente Entwicklungen in Städten. Climate change and biodiversity loss, as well as urbanisation and demographic change, are major global challenges of the 21st century. These trends have profound impacts on cities and their ecosystems and thus on the living conditions of the majority of humanity. This raises the need for timely environmental monitoring supporting sustainable and resilient urban developments. The first article is an overview of the state of the art of remote sensing science in relation to urban ecology. The review found that remote sensing can contribute to sustainable urban policy, still insufficiencies remain as many studies are not directly actionable. The second article shows that a growing city can provide opportunities for an increase in green infrastructure. Here, remote sensing is used for long-term analysis of land-use in relation to urban forms in Berlin. The third article examines how urban density affects ecosystem service provision of urban green infrastructure. It is shown that residential density does not necessarily lead to poor biodiversity potential or cooling capacity. However, dense areas with low vegetation cover are particularly dependent on major green infrastructure. The fourth article explores ways to reinforce nature-based solutions by better connecting and informing stakeholders. Based on a focussed literature review on information technology supporting urban social-ecological systems, a decision support tool is developed. The tool combines indicators based on ecological diversity and performance with population density and vulnerability. This way, climate change adaptation can be developed in accordance with socio-ecological conditions. The concluding fifth article offers an outlook on a larger framework in support of urban sustainability, based on the ecological trait concept. Together the five research papers provide pathways for urban remote sensing science and applied spatial planning that can support sustainable and resilient developments in cities.

Στόχος της διατριβής - Οι παράκτιες περιοχές αποτελούν, μεταξύ άλλων, πολύτιμα οικοσυστήματα λόγω των κοινωνικο-οικονομικών και οικολογικών ωφελειών αλλά και υπηρεσιών που προσφέρουν. Οι ανθρώπινες δραστηριότητες ασκούν πιέσεις στα παράκτια ενδιαιτήματα προκαλώντας πολλαπλές δυσμενείς επιπτώσεις και κυρίως απειλούν τα οφέλη που αυτά προσφέρουν. Συνεπώς, οι θαλάσσιοι διαχειριστές και οι χαράσσοντες πολιτική καλούν ολοένα και περισσότερο για καινοτόμες προσεγγίσεις και εργαλεία ικανά να κατανοήσουν τις περίπλοκες αλληλεπιδράσεις που αναπτύσσονται ανάμεσα στις φυσικές και ανθρωπογενείς αλλαγές, με στόχο τη διαφύλαξη της οικοσυστημικής ακεραιότητας μέσω της άμβλυνσης των συγκρούσεων. Για την επίτευξη του απώτερου στόχου που αφορά την εξάπλωση των θαλάσσιων ανθρώπινων δραστηριοτήτων, το συντονισμό του παράκτιου περιβάλλοντος και της θαλάσσιας οικονομίας καθώς και το ζήτημα της βιώσιμης συνύπαρξης, κρίνεται απαραίτητο ένα σχέδιο Παράκτιου Χωροταξικού Σχεδιασμού (ΠΧΣ) που ακολουθεί προσέγγιση που βασίζεται στο οικοσύστημα. Ο ΠΧΣ στοχεύει στην επίλυση αυτής της αντίφασης συμβαδίζοντας με τη Οδηγία Πλαίσιο για τη Θαλάσσια Στρατηγική (ΟΠΘΣ) της ΕΕ, μεταξύ άλλων Οδηγιών της ΕΕ. Η κινητήριος δύναμη και συνιστώσα για την παρούσα διατριβή αποτελεί η ανάλυση ζητημάτων σχετικά με την «βήμα προς βήμα» προσέγγιση για την ανάπτυξη ενός παράκτιου χωροταξικού σχεδίου σε μια περιοχή με ελλιπή δεδομένα, τη νότια και βόρεια παράκτια περιοχή του Νομού Ηρακλείου στην Κρήτη (Ελλάδα). Αυτή η ολοένα και πιο απαιτητική πρόκληση απαιτεί τον καθορισμό στόχων, προετοιμασία, ανάλυση και αξιολόγηση. Προς αυτή την κατεύθυνση, αναπτύχθηκε μια καινοτόμος Οικοσυστημική Αξιολόγηση Κινδύνου (ΟΑΚ) και μία τροποποιημένη ανάλυση των συγκρούσεων. Η διεπιστημονική προσέγγιση εκφράζεται μέσα από τους ακόλουθους στόχους: (α) τη διερεύνηση των σταδίων και διαδικασιών για την αποτελεσματική εφαρμογή του ΠΧΣ σε μια παράκτια περιοχή με ελλιπή δεδομένα μέσω της βιβλιογραφικής ανασκόπησης, (β) την αντιμετώπιση της έλλειψης δεδομένων με την ανάπτυξη κι ενοποίηση υποκατάστατων δεδομένων (proxy) αλλά και την επεξεργασία ποικίλων κι ανομοιόμορφων δορυφορικών ή άλλων δεδομένων εφαρμόζοντας γεωχωρικές αναλύσεις και εργαλεία, (γ) την πρόταση ενός ολοκληρωμένου πλαισίου χωροταξικού σχεδιασμού μέσα από το οποίο οι αλληλεπιδράσεις στεριάς-θάλασσας αντιμετωπίζονται ταυτόχρονα, (δ) την εξασφάλιση στατιστικά ορθών αποτελεσμάτων, (ε) την πρόταση ενός καινοτόμου μοντέλου εξίσωσης βασισμένο στη διασύνδεση των ανθρώπινων δραστηριοτήτων και των κύριων πιέσεων καθώς και της επίδρασής τους πάνω στις οικοσυστημικές υπηρεσίες για τον προσδιορισμό περιοχών των παράκτιων οικοσυστημάτων που βρίσκονται σε κίνδυνο, (στ) τον προσδιορισμό περιοχών των παράκτιων οικοσυστημάτων που βρίσκονται σε κίνδυνο, (ζ) τον προσδιορισμό των συμβατοτήτων και των συγκρούσεων τόσο ανάμεσα στις ανθρώπινες δραστηριότητες όσο και ανάμεσα στις ανθρώπινες δραστηριότητες και το παράκτιο περιβάλλον, (η) την εκτίμηση της αναγκαιότητας λήψης αποφάσεων για σχέδια καθορισμού ζωνών, διασφαλίζοντας την απαραίτητη συνοχή και συμβατότητα ανάμεσα στις ανθρώπινες δραστηριότητες, το περιβάλλον και τις υφιστάμενες πολιτικές, (θ) σύμφωνα με τα χαρακτηριστικά της υπό μελέτη περιοχής, την πρόταση προσαρμογών για την ανάπτυξη ενός αποτελεσματικού πλαισίου ΠΧΣ με προσέγγιση βασισμένη στο οικοσύστημα το οποίο θα μπορούσε να εφαρμοστεί σε παρόμοιες περιοχές. (ι) Τέλος, αυτή η διατριβή αναλύει τους περιορισμούς αλλά και την αποτελεσματικότητα των μοντέρνων γεωχωρικών εργαλείων στον ΠΧΣ. Μεθοδολογία - Ο ορισμός και η χαρτογράφηση συγκεκριμένων και αξιόπιστων δεδομένων σχετικών με τα οικοσυστημικά και κοινωνικο-οικονομικά στοιχεία αποτελεί καίριο σημείο στη διερευνητική διαδικασία ενός αποτελεσματικού παράκτιου ΠΧΣ στο πλαίσιο χωρικής διαχείρισης βασισμένης στο οικοσύστημα. Ωστόσο, σε πολλές περιπτώσεις, η έλλειψη σχετικών περιβαλλοντικών δεδομένων μεταβλητών εμποδίζει την ανάπτυξη βιώσιμων πολιτικών και πρακτικών. Σε αυτό το πλαίσιο, είναι πρωταρχικής σημασίας μια ισχυρή και ολιστική αντίληψη της κατάστασης του παράκτιου οικοσυστήματος μέσω της οριοθέτησης της χωρικής μεταβολής των ανθρώπινων δραστηριοτήτων, των συναφών κύριων πιέσεων καθώς και των τελικών οικοσυστημικών υπηρεσιών αλλά και των αλληλεπιδράσεών τους. Η τηλεπισκόπηση στη θάλασσα έχει χρησιμοποιηθεί εκτενώς για να παρέχει τέτοιου είδους δεδομένα, με περιορισμένη όμως επιτυχία λόγω των διαφορετικών χωρικών αναλύσεων, μη επικαλυπτόμενων πλεγμάτων (grids) και της διαφορετικής χωρικής έκτασης, καθώς στις περισσότερες περιπτώσεις, προέρχονται από διαφορετικές πηγές. Η παρούσα διατριβή προτείνει ένα εννοιολογικό πλαίσιο για την ανάπτυξη και ενοποίηση χωρικά ανεξάρτητων κοινωνικο-οικοσυστημικών συνόλων δεδομένων στο περιβάλλον των Γεωγραφικών Πληροφοριακών Συστημάτων (ΓΠΣ), κάτι το οποίο λείπει. Τα σύνολα δεδομένων που χρησιμοποιήθηκαν στην διατριβή αναπτύχθηκαν μέσω της σύνθεσης υποκατάσταστων και δορυφορικών δεδομένων για τις θαλάσσιες και χερσαίες παραμέτρους. Αρχικά, η δημιουργία συνόλου δεδομένων με βάση την αρχική οριοθέτηση των υδροκριτών μέσω μιας αλληλουχίας βημάτων, παρείχε τη βάση για τον υπολογισμό της χερσαίας επίδρασης που δέχονται. Βελτιώνοντας τη δυνατότητα ανάπτυξης κι ενσωμάτωσης σημαντικής πληροφορίας στο πλαίσιο λήψης αποφάσεων όπου τα δεδομένα είναι περιορισμένα και με υψηλή αβεβαιότητα, είναι ουσιώδες να εμπλακεί ένα μεγάλο εύρος γεωχωρικών δεδομένων κατά τη διάρκεια του χειρισμού των δεδομένων και τη διαδικασία κατασκευής γεωβάσης, όπως είναι η βέλτιστη παρεμβολή Ordinary Kriging (ΟΚ) που συμπληρώνει τα κενά στα δεδομένα κοντά στην ακτογραμμή, η πυκνότητα Kernel, κτλ. Ακόμα ένα ζωτικό σημείο της προσέγγισης του ΠΧΣ βασισμένης στο οικοσύστημα αποτελεί η χαρτογράφηση της χωρικής κατανομής των κυρίαρχων πιέσεων και η αναγνώριση των Βασικών Περιβαλλοντικών Δεικτών (ΒΠΔ). Τα σύνολα δεδομένων των πιέσεων περιελάμβαναν τη φθορά του πυθμένα λόγω τριβής, τη χλωροφύλλη-α, τα εμπορικά αλιεύματα, τα χωροκατακτητικά είδη, τη φωτορύπανση, τα μικροπλαστικά, την ηχορύπανση, την οξίνηση των ωκεανών και το οργανικό φορτίο. Αυτά οι εννέα Πιθανοί Περιβαλλοντικοί Δείκτες (ΠΠΔ) υπεβλήθησαν σε Ανάλυση Κύριων Συνιστωσών (ΑΚΣ) προκειμένου να μειωθεί ο αριθμός των παραμέτρων και να αναγνωριστούν οι μεταξύ τους σχέσεις. Η αξιολόγηση της συνύπαρξης των ανθρώπινων δραστηριοτήτων εμπλέκει τις αλληλεπιδράσεις μεταξύ των χρήσεων αλλά και μεταξύ χρήσεων και περιβάλλοντος. Η ΑΟΚ αποτελεί μια προσέγγιση αξιολόγησης της αλληλεπίδρασης μεταξύ χρήσεων και περιβάλλοντος, ενώ η προσέγγιση της αλληλεπίδρασης μεταξύ των χρήσεων πραγματοποιήθηκε μέσω της συμβατότητας των θαλάσσιων χρήσεων ανά ζεύγη σύμφωνα με την υφιστάμενη βιβλιογραφία. Η προσέγγιση της ΟΑΚ σε συνδυασμό με την ανάλυση συγκρούσεων μέσω της εφαρμογής των εμπλεκόμενων μοντέλων μπορεί να αναδείξει τις ασυμβατότητες. Συγκεκριμένα, το προτεινόμενο μοντέλο εξίσωσης ΟΑΚ που εμπλέκει τις σταθμισμένες κύριες πιέσεις, τις ανθρώπινες δραστηριότητες (θαλάσσιες και χερσαίες) που τις ασκούν αλλά και τις τελικές οικοσυστημικές υπηρεσίες (Προμηθευτικές, Ρυθμιστικές, Διατήρησης, Πολιτιστικές) (βλέπε Πίνακα 3) σε ένα παράκτιο περιβάλλον, παρέχει έναν τρόπο χωρικής διερεύνηση των περιβαλλοντικών επιπτώσεων από τις ανθρώπινες δραστηριότητες πάνω στην παροχή και διατήρηση των τελικών οικοσυστημικών υπηρεσιών. Τα αποτελέσματα της Επίπτωσης Κινδύνου (ΕΚ) ομαδοποιήθηκαν με τη χρήση της ανάλυσης θερμών σημείων (hotspot analysis) μέσω του στατιστικού δείκτη Getis-Ord Gi*. Η προτεινόμενη ανάλυση συγκρούσεων χρησιμοποίησε πίνακες συγκρούσεων και χάρτες συμβατότητας/ασυμβατότητας προκειμένου να καθοριστεί η ποσοτική αξιολόγηση των συγκρούσεων ανάμεσα στις θαλάσσιες ανθρώπινες δραστηριότητες. Ευρήματα - Ο σχεδιασμός της μεθοδολογίας ανέπτυξε χάρτες που βασίζονται στα ΓΠΣ σε όλα τα βήματα που παρουσιάστηκαν. Τα αποτελέσματα της ΑΚΣ υποδεικνύουν ότι η προτεινόμενη μεθοδολογία συμπλήρωσης κενών είναι έγκυρη κι ανεξάρτητη από τα χαρακτηριστικά των δεδομένων τηλεπισκόπισης. Η αποτελεσματική μεθοδολογία που προτείνεται για την ενοποίηση κι ενσωμάτωση των ποικίλων δορυφορικών δεδομένων και των αναπτυγμένων υποκατάσταστων παραμέτρων επέτρεψε τη στατιστική ανάλυση η οποία ανέδειξε 7 ΒΠΔ: οργανικό φορτίο, χλωροφύλλη-α, φθορά του πυθμένα λόγω τριβής, εμπορικά αλιεύματα, φωτορύπανση, μικροπλαστικά και ηχορύπανση, υποδεικνύοντας τη συμπερίληψή τους στα αρχικά στάδια εφαρμογής του ΠΧΣ. Τα αποτελέσματα της προτεινόμενης ανάλυσης ΟΑΚ παρουσιάζουν ιδιαίτερα χαμηλές ΕΚ τιμές που συγκεντρώνονται στο βόρειο τμήμα της μελέτης περιοχής, κοντά στην ακτογραμμή, όπως αναμενόταν. Η ανάλυση θερμών σημείων που βασίστηκε στα αποτελέσματα της ΕΚ, ανέδειξε μια ευρύτερη περιοχή σε κίνδυνο. Τα αποτελέσματα έδειξαν ότι στο πλαίσιο της παρούσας κατάστασης υπάρχουν ανάμεσα στις θαλάσσιες ανθρώπινες δραστηριότητες μόνο ασυμβατότητες υπό συνθήκη. Σε γενικές γραμμές, τόσο η βόρεια όσο και η νότια περιοχή μελέτης επιτυγχάνουν τους στόχους της βιωσιμότητας επί του παρόντος και δεν απαιτούν σχέδια οριοθέτησης. Πρωτοτυπία – Η καινοτόμος ενοποίηση των χερσαίων και θαλάσσιων διαδικασιών αξιολογείται για πρώτη φορά σε ένα περιεκτικό χωρικό σχέδιο. Η παρούσα διατριβή αποτελεί την πρώτη χωροταξική προσπάθεια που αποτυπώνει κι εμπλέκει την επίπτωση των χερσαίων ανθρώπινων δραστηριοτήτων στο θαλάσσιο περιβάλλον, διαμέσου μειούμενης συνάρτησης. Αναπτύχθηκαν καινοτόμες μεθοδολογίες επιλύοντας ζητήματα, όπως ανάπτυξη υποκατάστατων δεδομένων καθώς και ενοποίηση δεδομένων, σε συνθήκες έλλειψης δεδομένων, προκειμένου να επιτραπεί η εφαρμογή του ΠΧΣ με εφικτό, αποδοτικό και όσο το δυνατόν λιγότερο μεροληπτικό τρόπο, συνεισφέροντας στη βελτίωση της διαδικασίας του ΠΧΣ. Η διατριβή αυτή συνεισφέρει περαιτέρω με την πρόταση εντός μοντέλου εξίσωσης υπολογισμού της Επίπτωσης Κινδύνου, λαμβάνοντας υπόψη τις ανθρώπινες δραστηριότητες και τη διασύνδεσή τους με τις σταθμισμένες κύριες πιέσεις που επηρεάζουν συνολικά τις τελικές οικοσυστημικές υπηρεσίες. Επιπροσθέτως, η ανάλυση συγκρούσεων σε συνδυασμό με τα αποτελέσματα της ΑΟΚ εξίσωσης συνέβαλαν στον προσδιορισμό των ασυμβατοτήτων. Παρ’ όλους τους περιορισμούς και τα εμπόδια που προέκυψαν κατά τη διάρκεια της ερευνητικής διατριβής, τα διδάγματα που προέκυψαν από τα προαναφερθέντα αποτελέσματα αντιπροσωπεύουν ένα βήμα προόδου συγκριτικά με άλλες μεθοδολογίες που αναπτύχθηκαν μέχρι στιγμής. Aim of the dissertation - Coastal regions are among the most valuable ecosystems due to the socioeconomic and ecological benefits and services they provide. Human activities exert pressures, leading to multiple adverse effects on coastal habitats and seriously jeopardize these benefits. Consequently, marine managers and policy-makers are increasingly calling for new approaches and tools able to fully understand the complex interactions between natural and human-induced changes, with a view to safeguarding ecosystem integrity by alleviating conflicts. To achieve the ultimate goal of expanding marine human uses, coordination of coastal environment and marine economy as well as sustainable coexistence, a Coastal Spatial Planning scheme following an ecosystem-based approach is needed. Coastal Spatial Planning (CSP) aims to resolve this contradiction in parallel with the E.U. Marine Strategy Framework Directive, among other EU Directives. The main driver and motivation of this dissertation is to analyse issues pertaining to a step-by-step approach towards the development of a coastal spatial plan in a data-poor region, the northern and southern coastal area of Heraklion Prefecture, in Crete (Greece). This increasingly challenging task requires objectives stipulation, preparation, analysis and evaluation. In this direction, a novel Ecosystem Risk Assessment (ERA) model and a modified conflict analysis are developed. Multisciplinarity is expressed through the following objectives: (i) investigate phases and procedures for the effective CSP implementation in a coastal data-poor region through literature review, (ii) overcome data shortage by developing and integrating surrogate data yet treating diverse and patchy satellite or other datasets by applying geospatial analyses and tools, (iii) propose a comprehensive spatial planning framework through which land-sea interactions are addressed simultaneously, (iv) assure statistically sound outcomes, (v) propose an innovative equation model based on human uses – key pressures linkages and their impact on ecosystem services to identify areas under risk for coastal ecosystems, (vi) identify compatibilities and incompatibilities between human uses as well as between human uses and coastal environment, (vii) estimate the need for zonation plans planning decisions, ensuring the necessary coherence and compatibility between human uses, environment and existing policies, (viii) based on the characteristics of the study area, propose adjustments in order to develop an effective ecosystem-based approach CSP scheme, that can be applied to other similar areas. (ix) Finally, this dissertation discusses the limits and efficacy of modern geospatial tools in CSP. Methodology - The definition and mapping of accurate and sound data concerning ecosystem and socio-economic components is a key aspect of the scoping process of effective CSP within the ecosystem-based spatial management context. In many cases, however, the lack of pertinent environmental variable datasets hinders the development of sustainable policies and practices. Under this framework, a robust and holistic understanding of the coastal ecosystem state by demarcating the human uses, pertinent key pressures as well as final ecosystem services spatial variation and their interactions is of utmost importance. Marine remote sensing has been used extensively to provide such datasets, with limited success due to different spatial resolutions, non-overlapping grids, and different spatial extent, since, in most cases, they are derived from miscellaneous sources. This dissertation proposes a conceptual framework for developing and homogenizing spatially explicit socio-ecosystemic datasets in a Geographical Information Systems (GIS) environment, which is lacking. The datasets, used in this dissertation, were developed from a synthesis of proxy and satellite data for sea- as well as land-based variables. At a starting design state, dataset generation from an initial watershed delineation cascade development provided the foundation of terrestrial influence estimation. Improving the capacity to develop and integrate crucial information in decisional contexts where data are limited and uncertainty is high, is therefore essential to employ a wide range of geospatial tools, during the data handling and geodatabase construction procedure, such as Ordinary Kriging (OK) as an interpolator of satellite data gap-filling near the shoreline, Kernel density, etc. Another crucial part of ecosystem-based CSP is mapping the spatial distribution of pertinent pressures, and identifying Key Environmental Indicators (KEIs). The pressure datasets, used, included abrasion, chlorophyll-a, commercial fish catches, invasive species, light pollution, microplastics, noise pollution, ocean acidification and organic load. These nine Potential Environmental Indicators (PEIs) were subjected to Principal Component Analysis (PCA) in order to reduce the number of parameters and identify their relationships. Human uses coexistence assessment involves both use-use and use-environment interactions. ERA constitutes a use-environment assessment approach, while a use-use approach is drawn by pairwise marine use compatibility knowledge from existing literature. ERA approach combined with the conflict analysis through the application of their entailed models could give prominence to incompatibilities. In particular, the proposed ERA equation model, engaging scored key pressures and exerted human uses (both marine and terrestrial) yet final ecosystem services (Supporting, Regulating, Provisioning, Cultural) (see Table 3) on the coastal environment, provides a means of spatially exploring environmental impacts of human uses on the final ecosystem services preservation and provision. Impact Risk (IR) results were further clustered using Hotspot analysis via Getis-Ord Gi* statistic. A proposed conflict analysis system employing conflict matrices and compatibility/incompatibility maps has been established to quantitatively evaluate the conflicts among marine human activities. Findings - The designed methodology elaborated GIS-based maps in all research steps. The OK results indicate that the proposed data gap-filling methodology is valid and independent of remote-sensing data characteristics. The effective proposed homogenization and integration of fully diverse satellite datasets and developed proxy variables enabled statistical analysis which showcase 7 shortlisted KEIs: οrganic load, chlorophyll-a, abrasion, commercial fish catches, light pollution, microplastics and noise pollution, indicating their inclusion in the initial steps of CSP implementation. The proposed ERA analysis results were to be expected and showed basically low IR values mostly concentrated in the northern part study area near the coastline. Hotspot analysis based on the IR results unveiled a more extended under-risk area. The results showed that under the current state only incompatibilities under conditions among marine human uses exist. In general terms, both the northern and southern study area meet, at present, the sustainability goals and do not call for zoning schemes. Originality - The novel integration of terrestrial and marine processes is empirically assessed for the first time in a comprehensive spatial plan. This dissertation constitutes the first planning attempt to capture and involve the impact of terrestrial human uses on the marine environment, via a decay function. Novel methodologies have been developed addressing issues, such as proxy datasets development and datasets integration, related to data-limited situations, in order to enable CSP implementation in a feasible, cost-effective and less biased way, contributing to the CSP process improvement. This dissertation contributes further by proposing an equation model of Impact Risk calculation, considering human uses and their scored linkages of key pressures that affect the final ecosystem services altogether. Additionally, conflict analysis, coupled with ERA equation results facilitated incompatibility identification. Despite the limitations and impediments encountered during the research dissertation, lessons learned, as outlined in the above outcomes, represent a step forward compared to methodologies developed so far. Not available until 03/07/2025

The capstone project aims to modify and finalize an existing hydroponic crop cultivation (HCC) system, called the "Fold-out-Farm," to operate on a floating platform in Small Island Developing States (SIDS) that are susceptible to food insecurity due to natural and economic factors. Specifically, when SIDS are hit by natural disasters, crops and agricultural infrastructure can be severely damaged, causing many people to suffer from a lack of both food access and job opportunity. The Fold-out-Farm is completely self-sufficient – it has its own water collection system, solar-based power generation, and on-board growing pods. The unit can float to combat disaster consequences from incidents such as hurricanes. Specifically, the project is working to add a rainwater harvesting system and validate the structural integrity of the unit during a flood. The farm is designed to use off-the-shelf nutrient solutions to grow a variety of crops and the team will find the most suitable option. The team will also expand the market niche for the HCC system by determining the optimal use for the product in urban food deserts, refugee camps, and rooftop gardens. The approach taken has involved communication and research to understand the needs of those who could benefit from a Fold-out-Farm, as well as various testing methods for crops and structure of the unit. Testing has been done through expert surveys, estimation of structural performance, simulation software analysis, and evaluation of crop yield from the unit relative to a control crop grown in soil. Results will be continuously measured, first in testing the system’s ability to deliver water, sun and nutrients to growing modules, its crop yield, and stability in an open water test in the Rivanna river, and finally when presenting the design to sponsors and potential users. Future researchers may build upon these findings to further improve the unit and its potential use to ensure that it is understandable and acceptable to the communities who will be using it. The project will have a market-ready product capable of reducing food insecurity in SIDS and potentially in urban food deserts, refugee camps and rooftop gardens in land scarce areas. The Science, Technology, and Society (STS) report details how the development of an aquaculture industry in the Great Lakes basin of North America can diversify food production and increase food security in the Midwest region of the United States. The report answers how aquaculture can be economically viable in the Midwest and why creating a thriving aquaculture industry in the Midwest would be advantageous for the region by increasing economic activity and food security. An analysis of a Midwest aquaculture industry through the lenses of actor network theory and technological momentum, two sociological frameworks, will be included. An outline of steps that can be taken by federal and state governments by creating an “open for business” posture, reducing regulations, and passing several tax exemptions that would incentivize investment in a Midwest aquaculture industry is discussed in addition to an analysis of general economic feasibility. The common theme of economic development, resiliency and sustainability ties these two projects together. Agriculture and aquaculture are both essential components of food production systems and play a vital role in ensuring food security and economic development in developing countries. Moreover, both fields are subject to socio-technical influences, and their success is heavily dependent on factors such as government policies, technological advancements, and social and cultural factors. Therefore, the technical work in agriculture and the STS research in aquaculture complement each other, providing a holistic approach to understanding and addressing the complex socio-economic challenges faced concerning economic well-being.

Raziskali smo vpliv podnebnih sprememb na debelinsko rast in lastnosti lesa smreke in bukve ter na razpoložljivost lesa in razvoj gozdno-lesnega biogospodarstva. Na različnih rastiščih po Sloveniji smo s prirastnim svedrom odvzeli vzorce bukve in smreke za dendrokronološke in lesno-anatomske raziskave ter z meritvami z rezistografom ocenili variabilnost gostote. Rezultati kažejo značilno zvezo med širino branike, lesno-anatomskimi posebnostmi in vremenskimi spremenljivkami. Potrdili smo značilno zvezo med zgradbo lesa in gostoto pri smreki, medtem ko pri bukvi teh zvez nismo ugotovili. Za oceno vpliva podnebnih sprememb ter gospodarjenja z gozdom smo simulirali različne načine gospodarjenja z gozdom in scenarije podnebnih sprememb na razpoložljivost lesa na trgu. Ugotovili smo, da načini gospodarjenja z gozdom ter ekstremni vremenski dogodki značilno vplivajo na razpoložljivost okroglega lesa na trgu. Razvili smo nacionalni input-output model za ovrednotenje možnih scenarijev prihodnjega razvoja gozdno-lesnega biogospodarstva. Iz rezultatov scenarijske analize input-output modela je razvidno, da lahko Slovensko gozdno-lesno biogospodarstvo preko prestrukturiranja gospodarskih aktivnosti v prihodnosti doseže do 20 % višjo vrednost proizvodnje, povečanje števila zaposlenih za 24 % ter povečanje dohodka gospodinjstev za 19 %. Podnebne spremembe bodo dolgoročno vplivale na drevesno sestavo in produktivnost slovenskih gozdov in s tem zahtevale tudi prilagoditev gozdno-lesnega biogospodarstva. V Sloveniji obstaja velik potencial multiplikativnih učinkov razvoja gozdno-lesne verige. Za izkoriščanje teh potencialov pa je treba razvoj gozdno-lesnega biogospodarstva načrtovati dolgoročno z jasno definiranimi cilji. In this thesis we examined the impact of climate change on the radial growth and wood properties of spruce and beech, as well as on wood availability and the development of the wood-based bioeconomy. Samples of beech and spruce were taken with an increment borer at different sites around Slovenia for dendrochronological and wood anatomical studies. Additionally, wood density variability was assessed using resistograph measurements. The results show a significant relationship between tree ring width, wood anatomical features and weather variables. We confirmed a significant relationship between wood structure and density in spruce, while no such relationship was found in beech. To assess the impact of climate change and forest management, we simulated different forest management practices and climate change scenarios on the availability of roundwood and found that forest management practices and extreme weather events have a significant impact on the availability of roundwood on the market. We developed a national input-output model to evaluate possible scenarios for the future development of the wood-based bioeconomy. The results of scenario analysis of the input-output model shows that the Slovenian wood-based bioeconomy can achieve up to 20% higher production value, 24% increase in employment and 19% increase in household income in the future through restructuring of economic activities. Climate change will cause a long-term change in the tree composition and productivity of Slovenian forests, and consequently require technological changes and adaptations of the wood-based bioeconomy. The wood value chain in Slovenia has a high potential for multiplier effects, while its development needs to be planned in the long term with clearly defined goals in order to exploit these potentials.

Klimawandel und Bodendegradation üben Druck auf die Nahrungsmittelproduktion sowie auf die Fähigkeit des Bodens zur Minderung des Klimawandels beizutragen aus. Bodendegradation hat negative Auswirkungen auf die Bodenqualität. Ziel dieser Arbeit ist die Analyse der Effekte von landwirtschaftlich getriebener Bodendegradation, vor allem durch Pflügen und dem Umgang mit Ernterückständen. Es wird ein Überblick über das Thema Bodendegradation gegeben, gefolgt von Erweiterung des globalen Ökosystemmodells Lund-Potsdam-Jena-managed-Land (LPJmL) um eine detaillierte Prozessabbildung von Pflugpraktiken und Effekten von Ernterückständen. Diese ermöglicht die Analyse der Effekten von landwirtschaftlichen Managements auf die Anpassung und Minderung des Klimawandel. Das Modell kann die Effekte von naturerhaltender landwirtschaftlicher Bewirtschaftung (im Englischen bekannt als Conservation Agriculture) auf Kohlenstoffvorräte im Boden und CO2 Emissionen simulieren. Im letzten Teil wird die historische Dynamik der Entwicklung von Bodenkohlenstoff (engl.: Soil Organic Carbon – SOC) und die Effekte von Annahmen zum zukünftigen Management unter unterschiedlichen Klimaszenarien gezeigt. Die Ergebnisse zeigen, dass durch die historische Umwandlung von natürlicher Vegetation zu landwirtschaftlicher Fläche bis zu 215 Pg SOC im Boden verloren gegangen sind. Bis zum Ende des Jahrhunderts könnten weitere 38 Pg SOC zusätzlich verloren gehen, wird die heutige landwirtschaftliche Fläche nicht nachhaltig bewirtschaften. Die Bewirtschaftung mit dem Pflug zeigt einen geringen Einfluss auf die Kohlenstoffvorräte des Bodens, während die Wahl der Behandlung von Ernterückständen erheblich Einfluss hat. Die Rückführung von Ernterückständen hat positive Einflüsse auf Bodenwassergehalt und Ernteproduktivität, mit regionalen Unterschieden. Insgesamt zeigen 46% der heute Landwirtschaftsfläche das Potenzial zur Steigerung des Bodenkohlenstoff, während mindestens 52% Kohlenstoff im Boden verlieren könnten. Climate change and increasing soil degradation put pressure on the global food production systems and the ability of land for climate change mitigation. Additionally, soil degradation has negative implications on soil quality. This thesis analyzes the effects of agricultural-driven global soil degradation, in particular tillage and residue management. At first, a review the state of knowledge on global soil degradation is provided. Soil organic carbon (SOC) decline is one of the major forms of soil degradation on cropland and a useful indicator of the status of soil degradation. Secondly, to study the effects of different pathways of agricultural management on biophysical and biogeochemical flows, the global ecosystem model Lund-Potsdam-Jena managed Land (LPJmL) is extended by a detailed representation of tillage practices and residue management. This improvement of LPJmL allows for the analysis of management-related effects on agricultural mitigation of climate change adaption and the reduction of environmental impacts. The model can simulate the effects of conservation practices on SOC stocks and CO2 emissions. And third, SOC development and the effects of different management assumptions under climate change is analyzed. This shows that approximately 215 Pg SOC was lost due to the historical conversion of natural land to cropland and up to 38 Pg SOC could be additionally lost on already existing cropland until the end of the century if cropland is not managed sustainably. The type of tillage system has small effects on the SOC stocks, while the choice of crop residue treatment is shown to be the main driver governing SOC development. Returning residues to the soil slows the decline of SOC, and positively affects soil moisture and crop productivity, with regional differences. In total, up to 46% of todays’ cropland shows the potential for SOC increase, while at least 52% of cropland today will undergo further SOC loss as a form of soil degradation.

Die Transformation des Energiesystems macht aufgrund zunehmend dezentraler, fluktuierender Stromeinspeisungen durch Wind- und PV-Anlagen, regelbare Stromproduzenten dringend erforderlich. Biogasanlagen können einen substanziellen Beitrag leisten, indem der Anlagenbetrieb flexibilisiert und somit bedarfsgerecht Strom bereitgestellt wird. Durch technische Anpassungen der Anlage, wie beispielsweise dem Ausbau der Gasspeicherkapazitäten und der BHKW-Leistung, lassen sich kurzfristige Schwankungen ausgleichen. Um das Stromerzeugungspotential über längere Zeiträume verlagern zu können, ist jedoch eine angepasste Fütterungsstrategie unabdingbar. Die Steuerung der Biogasproduktion birgt in der praktischen Umsetzung einige Herausforderungen. Einerseits ist die Konversion von Biomasse in Biogas ein komplexer Vorgang und zudem individuell für jede Biogasanlage zu betrachten. Bisher entwickelte Modelle nutzen daher Parameter zu sämtlichen charakteristischen Prozessphasen und Einflussgrößen, um die anaerobe Fermentation modellieren zu können. Demgegenüber steht die oftmals rudimentäre Ausstattung der Biogasanlagen mit Messtechnik, sodass entsprechende Parameter nicht zur Verfügung stehen. Im Rahmen dieser Arbeit wurde eine modellbasierte prädiktive Regelung des Biogasanlagenbetriebes entwickelt, die eine dem Bedarf angepasste Stromproduktion ermöglicht. Dabei wurde der Anspruch gefasst, besonders praxistaugliche Modelle zu entwickeln um erstmals einen erfolgreichen Einsatz auf nahezu allen Biogasanlagen mit keinen oder nur wenigen Anpassungen an der vorhandenen Messtechnik zu erlauben. Alle Untersuchungen, die dieser Arbeit zugrunde liegen, wurden auf Basis eines Reallabors, dem „Unterer Lindenhof“, durchgeführt. Dieses umfasst sowohl eine Praxisbiogasanlage als auch einen Energieverbrauch, der einem Dorf mit ca. 125 Einwohnern entspricht. In einem ersten Schritt wurden Prognosemodelle evaluiert, die den Strombedarf des Reallabors über 48 Stunden im Voraus vorhersagen sollen. Dabei wurden vier Modelle aus dem Bereich der Zeitreihenanalyse untersucht, ein TBATS und drei unterschiedliche ARIMA-Modelle. Über eine Evaluation von jeweils 366 Prognosen zeigten alle vier Modelle mit durchschnittlichen MAPE-Werten von 13-16 % ausreichend gute Resultate um einen Sollwert zur Orientierung des Biogasanlagenbetriebes zu liefern. Zusätzliche Untersuchungen ergaben zudem, dass die Prognose auch über einen Zeitraum von bis zu 14 Tagen erfolgen kann, ohne stärke Einbußen hinsichtlich der Prognosequalität. In einem weiteren Schritt wurde ein Modell zur Simulation der Biogasproduktion entwickelt. Dieses basiert ebenfalls auf der Zeitreihenanalyse, konkret auf einem Regressionsmodell. Damit unterscheidet es sich maßgeblich von bisherigen Entwicklungen in diesem Bereich, die in den meisten Fällen auf dem komplexen ADM1 beruhen. Sehr vorteilhaft erweist sich, dass das entwickelte Simulationsmodell lediglich historische Daten der letzten vier Wochen von der Biogasproduktion und der dosierten Menge an festen Substraten, unabhängig ihrer Zusammensetzung, als Inputparameter benötigt. Die Simulation der Biogasproduktion über 48 Stunden im Voraus erfolgt basierend auf Korrelationen, die die beiden Datensätze aufweisen. Eine Evaluation des Modells über 366 Simulationen ergab einen durchschnittlichen MAPE von 14-18 %. Dabei wurden die Daten von beiden Fermentern der Praxisbiogasanlage genutzt, die als eigenständige Systeme betrachtet werden können und damit die Adaptierbarkeit des Modells verdeutlichten. In einem dritten Schritt wurde die Fütterungsplanung zur bedarfsorientierten Biogasproduktion entwickelt. Für jeweils 48 Stunden im Voraus wurden 1500 randomisierte Fütterungspläne berechnet. Dabei wurden einige wenige Limitierungen vorgenommen, wie die maximale Substratmenge, die technisch in der Praxisbiogasanlage umsetzbar ist. Die aus den Fütterungsplänen voraussichtlich resultierende Biogasmenge konnte mittels des Simulationsmodells berechnet werden. Über einen Abgleich mit dem gewünschten Biogasbedarfsprofil konnte die Simulation mit den geringsten Abweichungen ermittelt und der zugehörige Fütterungsplan ausgewählt und umgesetzt werden. Die gesamte modellbasierte prädiktive Regelung wurde in einem praktischen Versuch im Reallabor „Unterer Lindenhof“ eingesetzt und eingehend geprüft. Über einen Zeitraum von 36 Tagen konnte ein durchschnittlicher MAPE von unter 20 % im Abgleich von der realen Biogasproduktion zu dem gewünschten Biogasbedarf erreicht werden. Dabei wurde in dem Testzeitraum der Biogasbedarf von dem prognostizierten Strombedarf des Reallabors abgeleitet. Die Untersuchungen der vorliegenden Arbeit zeigen, dass die entwickelte modellbasierte prädiktive Regelung eine bedarfsgerechte Stromproduktion auf einer großtechnischen Biogasanlage ermöglicht und aufgrund der erstmals sehr praxistauglichen Modelle eine Adaption auf nahezu jede Biogasanlage erlaubt. The transformation of the energy system requires controllable producers due to increasingly decentralised, fluctuating electricity generation from wind turbines and photovoltaics. Biogas plants can make a substantial contribution here by making plant operation more flexible and thus providing electricity as needed. Technical adjustments, such as the expansion of gas storage capacities and CHP output, can compensate for short-term fluctuations. However, in order to be able to shift the potential of electricity generation over longer periods of time, an adapted feed-in strategy is essential. The control of biogas production poses several challenges in practical implementation. First, the conversion of biomass into biogas is a complex process and must be considered individually for each biogas plant. Models developed so far use parameters for all characteristic process phases and influencing variables in order to be able to model anaerobic digestion. In contrast, biogas plants are often only rudimentarily equipped with measurement technology, so that corresponding parameters are not available. In this work, a model-predictive control of biogas plant operation was developed to enable demand-driven electricity generation. The aim was to develop models that are particularly well suited for practical use. Thus, for the first time, a successful application on almost all biogas plants could be possible without or with only minor adaptations to the existing measurement technology. All studies carried out in this thesis are based on a real-world laboratory, the "Unterer Lindenhof". This includes a practical biogas plant as well as an electrical consumption corresponding to that of a village with about 125 inhabitants. In a first step, forecasting models were evaluated to predict the electricity demand of the real-world laboratory over 48 hours in advance. Four models from the field of time series analysis were examined, one TBATS and three different ARIMA models. In an evaluation of 366 forecasts each, all four models performed sufficiently well to provide a set point for biogas plant operation, with average MAPE values of 13-16 %. Further investigations showed that forecasts can also be carried out over a period of up to 14 days without significant losses in forecast quality. In a further step, a model was developed to simulate biogas production. This is also based on time series analysis, or more precisely on a regression model. Thus, it differs significantly from previous developments in this field, which are mostly based on the complex ADM1. It turns out to be very advantageous that the developed simulation model uses as input parameters only historical data of the last four weeks of biogas production and the amount of solid substrates fed in, without considering their composition. The simulation of biogas production over 48 hours in advance is based on correlations resulting from these two data sets. An evaluation of the model over 366 simulations resulted in an average MAPE of 14-18 %. Data from both digesters of the biogas plant were used, which can be considered as independent systems, demonstrating the adaptability of the model. In a third step, the feeding schedule was developed for demand-based biogas production. For each 48 hours in advance, 1500 randomised feeding schedules were calculated. Some constraints were imposed, such as the maximum amount of substrate that is technically possible in the biogas plant. The biogas production expected from the feeding schedules could be calculated using the simulation model. By comparing the simulation with the desired biogas demand profile, the simulation with the least deviations could be determined and the appropriate feeding plan selected and implemented. The entire model predictive control system was used and thoroughly tested in a field trial at the real-world laboratory "Unterer Lindenhof". Over a period of 36 days, an average MAPE of less than 20 % was achieved in comparison between the real biogas production and the desired biogas demand. During the test period, the biogas demand was derived from the predicted electricity demand of the real-world laboratory. The investigations carried out show that the model-predictive control system developed enables demand-oriented electricity generation on full-scale and that, due to the models being very close to practice for the first time, adaptation to almost all biogas plants is possible.

Climate change poses a challenge for the production of crops in the twenty-first century due to alterations in environmental conditions. In Central Europe, temperature will be increased and precipitation pattern will be altered, thereby influencing soil moisture content, physiological plant processes and crop development in agricultural areas, with impacts on crop yield and the chemical composition of seeds. Warming and drought often occur simultaneously. The combination of multiple abiotic stresses can be synergistic, leading to additive negative effects on crop productivity. To date, little information is available from multi-factor experiments analyzing interactive effects of warming and reduced precipitation in an arable field. In addition, one major issue of studying climate change effects on crop development in the long-term is that weather conditions can vary strongly between years, e.g., with hot and dry summers in comparison to cool and wet ones, which directly affects soil moisture content and indirectly affects crop development. Thus, considering yearly weather conditions seems to be important for the analyses of climate change effects on aboveground biomass and harvestable yield of crops. The aim of the present work was to identify single and combined effects of soil warming (+2.5 °C), reduced summer precipitation amount (-25%), and precipitation frequency (-50%) on crop development, ecophysiology, aboveground biomass and yield as well as on yield quality of wheat, barley, and oilseed rape grown in the Hohenheim Climate Change (HoCC) field experiment. This thesis presents novel results from the HoCC experiment in the long-term perspective. Thus, aboveground biomass and yield data (2009-2018) of the three crops were analyzed with regard to their inter-annual variability, including annual fluctuations in weather conditions.This thesis consists of three publications. In the first and second publication a field experiment within the scope of the HoCC experiment was conducted with spring barley (Hordeum vulgare L. cv. RGT Planet) and winter oilseed rape (Brassica napus L. cv. Mercedes) in 2016 and 2017. The objective was to investigate the impacts of soil warming, altered precipitation pattern and their interactions on biomass production and crop yield. In addition, it was examined, whether the simulated climate changes affecting barley photosynthesis and the seed quality compounds of oilseed rape. In the third publication, long-term plant productivity data of wheat, barley, and oilseed rape were evaluated, including aboveground biomass and yield data from the field experiment in 2018 with winter wheat (Triticum aestivum L. cv. Rebell). Der Klimawandel stellt aufgrund veränderter Umweltbedingungen eine Herausforderung für den Anbau von landwirtschaftlichen Nutzpflanzen im 21. Jahrhundert dar. In Mitteleuropa steigt die Temperatur an und die Niederschlagsmuster verändern sich, wodurch die Bodenfeuchte, die physiologischen Pflanzenprozesse und die Pflanzenentwicklung in landwirtschaftlichen Gebieten beeinflusst werden. Dies wirkt sich auf den Ernteertrag und die chemische Zusammensetzung der Erträge aus. Häufig treten Erwärmung und Trockenheit gleichzeitig auf. Dabei kann sich das Vorkommen mehrerer abiotischer Stressoren synergistisch auswirken und zu additiv negativen Effekten auf die Pflanzenproduktivität führen. Bisher liegen nur wenige Informationen aus multifaktoriellen Experimenten vor, welche die Wechselwirkungen von Erwärmung und Trockenheit in einem landwirtschaftlichen Feld untersuchen. Darüber hinaus ist es wichtig die Auswirkungen des Klimawandels auf die Entwicklung von Nutzpflanzen in Langzeitstudien zu untersuchen, da die Wetterbedingungen zwischen den Jahren stark variieren können, z. B. mit heißen und trockenen Sommern im Vergleich zu kühlen und nassen, mit direkter Auswirkung auf die Bodenfeuchte und indirekter Wirkung auf die Entwicklung der Pflanzen. Demzufolge scheint eine Berücksichtigung der jährlichen Wetterbedingungen wichtig zu sein, wenn die Folgen des Klimawandels auf die oberirdische Biomasse und den Ernteertrag von landwirtschaftlichen Nutzpflanzen abgeschätzt werden. Das Ziel der vorliegenden Arbeit war es im Rahmen des Hohenheim Climate Change (HoCC) Feld-Experimentes die Folgen der drei Faktoren Bodenerwärmung (+2,5°C), reduzierter Sommer Niederschlagsmenge (-25 %) und Niederschlagshäufigkeit (-50 %) einzeln oder in Kombination auf die Parameter Pflanzenentwicklung, Ökophysiologie, oberirdische Biomasse, Ertrag und Ertragsqualität von Weizen, Gerste und Raps zu untersuchen. In dieser Arbeit werden neue Ergebnisse aus dem Langzeit - HoCC-Experiment präsentiert. Dazu wurden Daten von 2009-2018 zu oberirdischer Biomasse und Ertrag der drei Kulturen hinsichtlich ihrer zwischenjährlichen Variabilität analysiert und jährliche Schwankungen in den Witterungsbedingungen berücksichtigt. Die Dissertation besteht aus drei Publikationen. In der ersten und zweiten Veröffentlichung wurde im Rahmen des HoCC Experimentes in den Jahren 2016 und 2017 ein Feldversuch mit den Nutzpflanzen Sommergerste (Hordeum vulgare L. cv. RGT Planet) und Winterraps (Brassica napus L. cv. Mercedes) durchgeführt. Ziel war es, die Auswirkungen einer Bodenerwärmung, veränderten Niederschlagsmustern und deren Wechselwirkungen auf die Biomasseproduktion und den Ernteertrag zu untersuchen. Darüber hinaus wurde untersucht, ob sich die simulierten Klimaänderungen auf die Photosynthese von Gerste sowie auf die Inhaltsstoffe von Rapssamen auswirken. In der dritten Veröffentlichung wurden Langzeit - Produktivitätsdaten von Weizen, Gerste, und Raps ausgewertet, darunter oberirdische Biomasse und Ertragsdaten aus dem HoCC Feldversuch von 2018 mit Winterweizen (Triticum aestivum L. cv. Rebell).

New technologies and enhanced information systems are fueling digital transformation in many industries, including through the creation of new digital interfaces to communicate with and involve customers and suppliers. Information systems and management scholars have emphasized the far-reaching consequences of these endeavors for such areas as strategy, innovation, and entrepreneurship. The success of digital transformation depends on the willingness of the individuals involved, including customers, employees, and suppliers, to embrace these new technologies. Digital transformation is particularly difficult for family firms, as they usually follow conservative strategies, show resistance to change, and face resource restrictions, factors that limit their ability to pursue such substantial change to their business model. However, other factors can help family firms as they seek to transform and thrive: their strong and continuous organizational culture and their sustainable business activities, both of which are rooted in their socioemotional wealth considerations and strong social capital. Drawing on the technology acceptance model, we set out to explore the following research question: How do organizational characteristics of family firms shape the acceptance of new technologies among members within their supply chain? Our grounded theory model contributes to the literature about digital transformation in family firms by linking firm-level strategy to organizational and individual attributes; identifying factors that facilitate or hinder family firms’ digital transformation, such as a culture of innovation and change, as well as social capital embedded in inter- and intra-organizational relationships; and guiding managers of family firms on how to enhance their digital agenda. Scholars emphasize the importance of psychological ownership (i.e., a feeling of possession towards an object independent of legal ownership) for desired behaviors and attitudes in corporate contexts. Psychological ownership is a multi-level phenomenon, meaning that the emotional attachment it implies might pertain to the overall organization as well as to organizational sub-units (e.g., business units). Hitherto, however, there is little empirical evidence on the antecedents, consequences, and vertical spillover effects of psychological ownership. To address this research gap, our paper presents arguments explaining how psychological ownership positively affects organizational performance by diffusing from higher levels of the organization towards lower levels. Furthermore, we suggest that error management culture and high affective commitment within teams, constitutes environmental conditions that let psychological ownership thrive. To test our theorizing, we created a unique dataset combining archival data with two surveys among 1,536 employees and 66 managers of an organization. Our results indicate that psychological ownership towards the business unit indeed enhances performance and mediates the effect of psychological ownership towards the entire organization. Additionally, our findings suggest that error management culture and the increase of affective commitment in teams pose mechanisms that can enhance psychological ownership towards the business unit. With these findings, our study yields important theoretical and practical implications. The success of the ongoing sustainability transformation depends in large parts on both the sustainability in firms’ production of goods and the consumption choices of individuals. While firms and consumers already separately contribute to sustainable development, a key challenge still lies in accelerating collaborative efforts. In this study, we develop a conceptual model to demonstrate how firms can motivate sustainable consumption behavior amongst their customers by involving them in their sustainability activities. In particular, we introduce psychological ownership as the underlying mechanism that explains how customer involvement in sustainability activities translates into changes in individuals’ consumption choices. We further argue that this mechanism depends on the type of sustainability that a firm undertakes, i.e., whether it is embedded in or peripheral to a firm’s core business. Results from two scenario experiments and one field experiment broadly support our theorizing and contribute to management research by showing how firms can go beyond delivering sustainable products and services toward actively shaping consumption behavior. Our results additionally reveal that firms can derive further benefits from customer involvement in embedded sustainability since it incites higher extra-role behavior in the form of feedback-giving than involvement in peripheral sustainability, which firms can exploit to develop their sustainability strategy further.