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In order for the collaborations to be fruitful and sustainable between organisations and open source software (OSS) ecosystems, maintainers need to understand if, and how it is possible to evaluate OSS ecosystem health in an effective manner. Understanding how OSS maintainers characterise ecosystem health and how they evaluate these health characteristics using digital evaluation tools is interesting to analyse since it could give insight in how ecosystem health in practice is evaluated, which health aspects can be evaluated with the help of digital tools, and what barriers exists in the evaluation processes. This qualitative study is based on semi-structured interviews and was conducted in order to answer two research questions regarding this topic. The answers which were produced by the semi-structured interviews were transcribed and coded to later be analysed where conclusions could be drawn. The research attempts to broaden the academic perspective on how ecosystem maintainers view health and how health evaluation digital tools can help maintainers understand the state of their ecosystem health, and what barriers exist. It became clear during the research that answering how ecosystem health is to be characterized is incredibly difficult since the answer might differ in many ways depending on the nature of the project, where the project is in its life cycle, and who is asking the questions. Two views surrounding the definition of ecosystem health are presented, one revolving around longevity and the other revolving around an ecosystem life cycle perspective. Furthermore, Diversity, Governance, Activity and Licensing seem to be the health characteristics maintainers find to be the most important for ecosystem health evaluation. Out of these, tools such as the ones offered by CHAOSS, seem somewhat geared towards assessing Activity, Licensing and Diversity. Saving time and finding trends when evaluating health are examples of how tools help maintainers however, barriers exist for maintainers in smaller or younger projects who have not practiced health evaluation for a very long time. Finally, another barrier is the amount of additional context and human judgment which is needed when using tools for the health evaluation. / För att samarbetet mellan organisationer och öppen källkod (OSS) ekosystem ska vara gynnsamma och hållbara, måste ekosystemsunderhållare förstå om och hur det är möjligt att utvärdera OSS-ekosystemhälsa på ett effektivt sätt. Att förstå hur OSS-underhållare karaktäriserar ekosystemhälsa och hur de utvärderar dessa hälsoegenskaper med hjälp av digitala utvärderingsverktyg är intressant att analysera eftersom det skulle kunna ge insikt i hur ekosystemhälsa i praktiken utvärderas, vilka hälsoaspekter som kan utvärderas med hjälp av digitala verktyg, och vilka hinder som finns i utvärderingsprocesserna. Denna kvalitativa studie är baserad på semistrukturerade intervjuer och genomfördes för att besvara två forskningsfrågor inom detta ämne. Svaren som producerades av de semistrukturerade intervjuerna transkriberades och kodades för att senare analyseras där slutsatser kunde dras. Forskningen försöker vidga det akademiska perspektivet på hur ekosystemsunderhållare ser på hälsa och hur hälsoutvärderingsverktyg kan hjälpa underhållare att förstå hälsotillståndet för deras ekosystem, men också vilka hinder som finns i processerna. Det blev tydligt under forskningen att det är otroligt svårt att svara på hur ekosystemhälsa ska karakteriseras eftersom svaret kan skilja sig åt på många sätt beroende på projektets karaktär, var projektet befinner sig i sin livscykel och vem som ställer frågorna. Två synpunkter kring definitionen av ekosystemhälsa tas upp, en som kretsar kring livslängd, och den andra som kretsar kring ett ekosystemlivscykelperspektiv. Dessutom verkar Mångfald, Styrning, Aktivitet och Licensiering vara de hälsoegenskaper som underhållare anser vara de viktigaste för hälsoutvärdering av ekosystem. Av dessa verkar verktyg som de som erbjuds av CHAOSS något inriktade på att bedöma Aktivitet, licensiering och mångfald. Att spara tid och hitta trender när man utvärderar hälsa är exempel på hur verktyg hjälper underhållare, men hinder finns för underhållare i mindre eller yngre projekt som inte har praktiserat hälsoutvärdering under en längre period. Slutligen är en annan barriär den mängden ytterligare kontext och mänskligt omdöme som behövs när man använder verktyg för hälsoutvärderingen.

Purpose - The purpose of the thesis is to attend to apparent knowledge gaps in digital servitization andecosystem orchestration literature concerning: (1) understanding of the internal role distribution when orchestrating ecosystems in digital servitization; (2) need for increased knowledge on the capabilities required for ecosystem orchestration. To fulfill this purpose, the following objective was derived: how procurement can develop dynamic capabilities to orchestrate ecosystem-organization collaboration in digital servitization. Method - This thesis is built on a qualitative methodology using an inductive approach. Utilizing multi-actorperspectives on a single case study on a leading global manufacturing firm within the vehicle and transport industry. The studied procurement function within the case firm is currently in an early phase of building ecosystem collaborations to support the firm's overall digitalization and servitization journey. More than 40 interviews were conducted spanning across: various roles within the procurement function, various roles across other functions within the case firm tied to the procurement function, as well as other external actor's viewpoints. The interviews were analyzed through a thematic analysis approach. Findings - By building on the well-established dynamic capabilities perspective as a theoretical lens, the findings of this thesis reveal nine sets of capabilities within the respective clusters sensing, seizing, and reconfiguring. In addition, four groups of underlying preconditions, referred to as enablers, were identified. We combine these insights into a framework underscoring the need for both capability development but also supporting enablers for successful development and utilization of said capabilities. The framework thus summarizes our key findings whilst illustrating interdependencies between the identified capabilities and enablers, showcasing that procurement must both develop routines and leverage the enablers, to successfully transition into a role in which they orchestrate ecosystem-organization collaboration. Implications - Through empirically explicating key capabilities, enablers and their interdependence, our thesis provides broad implications for management and strategy research relating to dynamic capabilities for orchestrating ecosystems in digital servitization. Furthermore, we also contribute to the scarce literature on procurement tied to these research streams. Additionally, our findings carry implications for procurement managers guiding them in how to strategically adjust to the continuously transformative industry landscape shaped by the trends digitalization, servitization and their interplay. This through rethinking the role of procurement as an orchestrator for innovation and value co-creation within the organization as well asassociated ecosystems, as well as paving the path for transitioning into such a role. Limitations and future research - This thesis is generally bound to a single case study within a set industry segment, at an early phase of rethinking procurement and ecosystem collaborations. Further research is suggested to validate our findings through larger datasets, other study methodologies and expand into other contexts. For instance, focusing on cross-industry comparisons or analyzing procurement's role and capability needs depending on the different stages of ecosystem evolution. To drive a truly dynamic firm, we further suggest investigating what role different internal functions (e.g., sales, engineering, IT) with benefit can undertake in the ecosystem depending on varying ecosystem actors, structure and maturity.

Технологии хранения и анализа огромного количества информации разного типа являются актуальным направлением информационных технологий для всех компаний на сегодняшний день. Целью данной диссертационной работы является создание учебного пособия для студентов, разработчиков или простого человека, который хочет расширить свой кругозор, по экосистеме анализа данных «Hadoop». Данная научно–исследовательская работа представляет из себя учебное пособие по теме: «Экосистема анализа больших данных Hadoop». Эта система считается одной из основополагающих технологий «Big Data». / Currently, the technological methods of saving and analyzing of large amounts of information of different kinds are at the forefront of information technology development for most companies. The goal of the thesis is to create an instructional manual for students, web developers, and laypeople aiming to expand their tech savvy, about the ecosystem of big data analysis Hadoop. This research paper is a manual on “the Ecosystem of Big Data Analysis Hadoop.” This system is considered to be one of the groundbreaking technologies of “Big Data.”

Магистерская диссертация посвящена исследованию развития онлайн банков в России и дальнейшим перспективам данного направления. Предметом исследования являются экономические отношения, формируемые уникальными особенностями и чертами первого онлайн банка в России. Основной целью магистерской диссертации является разработка комплексной концепции модификации и совершенствования банковского сектора, на примере Тинькофф банка в условиях развития банковских онлайн сервисов на основе изучения теоретических и практических аспектов ведения деятельности онлайн банками. В заключении подводятся итоги проведенного исследования, делаются основные выводы и обобщаются перспективы развития Тинькофф Банка и постепенная трансформация в банковскую экосистему. / The master's thesis is devoted to the study of the development of online banking in Russia and the future prospects of this direction. The subject of the research is economic relations formed by the unique features and features of the first online Bank in Russia. The main goal of the master's thesis is to develop a comprehensive concept of modification and improvement of the banking sector, based on the example of Tinkoff Bank in the development of online banking services based on the study of theoretical and practical aspects of online banking. In conclusion, the results of the research are summarized, the main conclusions are made and the prospects for the development of Tinkoff Bank and its gradual transformation into the banking ecosystem are summarized.

As changing climate and growing urban populations present new challenges for managing both the quantity and the quality of storm waterin cities, nature-based solutions such as blue-green infrastructure arebecoming widely considered as an alternative to grey infrastructure. The benefits, above providing storm water management at a lower cost, are increased ecosystem services. One of such solutions is SuDS: a collective name for drainage systems thatare designed to manage the quantity of runoff, protect or enhance water quality, increase amenity and foster biodiversity. In Sweden there is a lack of research on applying nature-based solutions in planning urban water management. This case study aims to contribute with knowledge of how working with blue-green infrastructure in a systematic way effects the outcome of urban planning and what ecosystem gains can be expected. ASuDS design was created following the SuDS guidelines for a greenfield residential area in the city of Krokom. The design was then compared with the original proposal by the municipality.The results show that the systematic method that SuDS brings to watermanagement planning leads to a different design of a residence area than what traditional methods produce. At the same time the ability to handle extreme rain event is at least as robust, with the ability of the system to generate other ecosystem services and further strengthen the resilience of the area. Further research is needed for a more detailed analysis of the generated ecosystem services. / <p>2023-06-02</p>

Ecosystem disturbances are a significant and ongoing threat to wildlife, caused by both natural environmental changes and human impacts. These disturbances can have a range of impacts, but one of the most crucial is on the wildlife habitat. In tropical forests, one such disturbance that is occurring at an alarming rate is peat fires. Peatfires impact the forest structure and fragmentation, which in turn directly relate to the wildlife habitat, ultimately threatening the population and even risking extinction for certain species. Of particular concern is the population of orangutans in Indonesia, which is at risk due to the impact of peat fires. This research used an agent-based modelling approach to explore the impact of ecosystem disturbances on wildlife habitat. The focus was on the orangutan population in tropical forests affected by peat fires. A systematic review of agent-based models revealed a shift towards a more mechanistic representation of entities in wildlife response to disturbances. However, fire disturbances and primate species such as orangutans still have a limited number of models. To address this gap, two agent-based models are presented: PeatFire, a model of the ignition and spread of tropical peatfire, validated using data from a fire pattern in South Sumatra; and the BORNEO model, which simulates the movement behaviour of orangutans in a disturbed forest using real tree inventory data and orangutan tracking data from the Sebangau forest in Central Kalimantan. The models were calibrated and validated using state-of-the-art methods and high-performance computing. The study demonstrates the ability of ABM to tackle complex research problems in various fields, including wildlife response to disturbances. The models developed in this study are important examples of the shift towards a more mechanistic representation of agents in ABM, and contribute to advancing the field in this direction. The research offers insights into the impact of ecosystem disturbances on wildlife habitat and highlights the potential of ABM in addressing these issues.

Intensive Landwirtschaft ist eine der allgegenwärtigsten anthropogenen Bedrohungen für aquatische Ökosysteme und beeinflusst sowohl die abiotischen als auch die biotischen Eigenschaften von Fließgewässerökosystemen. Diese resultieren aus der Vielzahl von Störungen, die mit Landnutzungsänderungen verbunden sind, wie z.B. Uferkahlschlag und dem damit verbundenen Verlust von allochthonem organischem Material und Beschattung, Nährstoff- und Pestizidkontamination, Feinsedimenteintrag durch Erosion und Oberflächenabfluss, sowie beeinträchtigte Hydromorphologie und damit verbundenem Verlust von vielfältigen Lebensräumen. Umfangreiche Literatur zu den Auswirkungen von Landwirtschaft auf einzelne Ökosystemkomponenten wie Makroinvertebraten, Biofilm oder Fischfauna existiert bereits, wobei der Schwerpunkt hier zumeist auf strukturellen Ansätzen oder einzelnen Ökosystemprozessen liegt. Allerdings haben nur wenige Studien umfassende Auswertungen angestellt, wie intensive Landwirtschaft die Funktion des gesamten aquatischen Ökosystems und die Wechselwirkungen zwischen den Ökosystemkomponenten beeinflusst. Um komplexe Effektmuster landwirtschaftlicher Stressoren auf Fließgewässerstruktur- und funktion sowie mechanistische Wirkzusammenhänge zwischen trophischen Ebenen besser zu verstehen wurden im Rahmen der vorliegenden Arbeit zwei Bäche die innerhalb landwirtschaftlicher Einzugsgebiete liegen und zwei bewaldete Referenzbäche im Harz, Sachsen-Anhalt, hinsichtlich ihrer physiko-chemischen Eigenschaften, der Menge und der Einträge von benthischem organischem Material, der Primärproduktion und organischen Kohlenstoffkreisläufen sowie der Sekundärproduktion von Makroinvertebraten und Fischen über einen Zeitraum von 12-17 Monate miteinander verglichen. Intensive Landwirtschaft hatte starke Auswirkungen auf die physiko-chemischen Eigenschaften der untersuchten Bachoberläufe. Wir ermittelten spezifische Leitfähigkeitswerte in landwirtschaftlich genutzten Bächen, welche die Konzentration gelöster Ionen in bewaldeten Referenzbächen um eine Größenordnung übertrafen. Die Konzentrationen von gelöstem anorganischem Stickstoff und löslichem reaktivem Phosphor waren in den landwirtschaftlichen Bächen im Durchschnitt viermal höher und der pH-Wert war im Durchschnitt eine Einheit niedriger als in den bewaldeten Bächen. Die Wassertemperatur war in landwirtschaftlich genutzten Bächen im Durchschnitt 3°C wärmer und zeigte höhere tageszeitliche Schwankungen. Der Eintrag von partikulärem organischem Material (POM) in die landwirtschaftlichen Bäche war ca. 30-mal niedriger als der Eintrag in die Referenzbäche, und die Menge an benthischem organischem Material (BOM) war in landwirtschaftlichen Bächen signifikant niedriger als in den Referenzbächen. Landwirtschaftliche Fließgewässer wiesen signifikant höhere Mengen an feinem benthischem organischem Material (FBOM) auf, hatten aber geringere Bestände an grobem benthischem organischem Material (CBOM) als die Referenzgewässer. Während in bewaldeten Fließgewässern die zeitliche Dynamik des BOM einem saisonalen Muster folgte, waren die Schwankungen in den landwirtschaftlichen Fließgewässern überwiegend stochastisch und durch anthropogene Aktivitäten, wie das Mähen der Uferrandstreifen, beeinflusst. Auch die Retention von POM war in landwirtschaftlich genutzten Bächen im Vergleich zu bewaldeten Bächen deutlich geringer, was auf eine geringere morphologische Komplexität und die größere hydrologische Variabilität, insbesondere auf die Abflussganglinien, zurückzuführen ist. Innerhalb des Experimentes zur Aufnahme von gelöstem organischem Kohlenstoff (DOC) war die Biofilmqualität in den landwirtschaftlichen Bächen ebenfalls höher. Interessanterweise zeigte jedoch der landwirtschaftliche Bach Hassel einen höheren Grad an Heterotrophie als der bewaldete Bach Wormsgraben. Da die biofilmspezifische DOC-Aufnahme im bewaldeten Bach nur 4 % der Gesamtaufnahme betrug, kann davon ausgegangen werden, dass die mikrobiell vermittelte Verarbeitung von Nährstoffen in der hyporheischen Zone den größten Anteil an der DOC-Aufnahme ausmachte. Vermutlich begünstigte die höhere Verweildauer und der bessere Austausch zwischen Oberflächenwasser und der hyporheischen Zone im bewaldeten Bach Wormsgraben die heterotrophe Nährstoffumsetzung im interstitiellen Porenraum. Die Bewertung der Makroinvertebraten-Gemeinschaft ergab, dass der Artenreichtum in landwirtschaftlichen Bächen im Vergleich zu bewaldeten Bächen um die Hälfte reduziert war. Die Biomasse, Dichte und Sekundärproduktion der Makroinvertebraten (Makroinvertebratensekundärproduktion, MSP) nahm jedoch entlang eines Gradienten der Ressourcenqualität und -quantität zu, mit höchster Produktivität im landwirtschaftlichen Bach Sauerbach, gefolgt vom landwirtschaftlichen Bach Getel und den bewaldeten Bächen Ochsenbach und Wormsgraben. Der Anstieg der MSP war hauptsächlich auf Zunahmen innerhalb der funktionellen Ernährungsgruppen der Sedimentfresser und Weidegänger zurückzuführen. Höhere MSP, Biomasse und Dichte korrelierten positiv mit niedrigeren N:P- und C:P-Verhältnissen des Biofilms und der Ressourcenmenge (höhere Biofilm-Zuwachsrate und Menge an krautiger Vegetation, Chlorophyll a-, TDN- (Summe an gelöstem Stickstoff), SRP- (gelöster reaktiver Phosphor) und POC- (Partikulärer organischer Kohlenstoff) Konzentrationen von Biofilm und Seston). Hohe Interaktionsstärken zwischen Zerkleinerern und grobpartikulärem organischem Material (CPOM) in landwirtschaftlichen Bächen deuteten auf eine Ressourcenlimitierung durch allochthones organisches Material hin. Da die Interaktionsstärken zwischen Weidegängern und Biofilm sowie zwischen feinpartikulärem organischem Material (FPOM) und Sammlern in landwirtschaftlichen Bächen deutlich geringer waren als in bewaldeten Bächen ist anzunehmen, dass die Gruppe der Zerkleinerer diese Limitation durch hohe funktionelle Plastizität und damit alternative Ressourcennutzung ausgleichen konnten. Die Analyse der Fischsekundärproduktion und Interaktionsstärken zwischen Fischen und ihrer Makroinvertebraten-Beute konnte zusätzlich zeigen, dass die landwirtschaftliche Flächennutzung zu einer starken Verschiebung des Fischartenspektrums führen und die Top-down Kontrolle der MSP durch Fische dadurch deutlich zurückgehen kann. Diese Ergebnisse zeigen, dass der Verlust der Ufervegetation und die übermäßige Nährstoffbelastung ökologische Nischen homogenisieren und hochproduktive Generalisten mit hoher Nahrungsplastizität begünstigten, die flexibel zwischen ubiquitären und stochastisch verfügbaren Nahrungsressourcen wechseln können. Insgesamt konnten wir mit dieser Studie darlegen, durch welche Mechanismen aus hoch-diversen, nährstoffbegrenzten, bewaldeten Bachoberläufen, die stark von terrestrischen Laubeinträgen abhängig sind, durch landwirtschaftliche Flächennutzung homogene, nährstoffbelastete und taxonomisch vereinfachte Bäche, mit einem hohen Maß an Autochthonie, werden können. Die gleichzeitige Analyse struktureller und funktioneller Indikatoren zeigte, dass die Landwirtschaft strukturelle Messgrößen wie den Artenreichtum beeinflusst, ohne dass es zu größeren Veränderungen in der Funktion kommen muss (ähnliche MSP im landwirtschaftlich genutzten Bach Getel im Vergleich zu bewaldeten Referenzbächen), und dass die Variabilität in der Funktion (Retention von organischem Material, Laubabbau) nicht automatisch die Informationen widerspiegelt, die die üblicherweise bewerteten chemischen oder biologischen strukturellen Messgrößen liefern. Die Ergebnisse dieser Arbeit zeigen deutlich, dass eine Kombination mehrerer struktureller und funktioneller Indikatoren entlang der Nahrungsnetzhierarchie erforderlich ist, um mechanistisch zu verstehen, wie intensive Landwirtschaft die Ökosysteme von Fließgewässern beeinflusst. So erlaubten z.B. nur die Informationen über die Qualität und Quantität der Primärproduktion, in Kombination mit strukturellen und funktionellen Informationen über die Makroinvertebratengemeinschaft, ein mechanistisches Verständnis darüber, wie landwirtschaftliche Stressoren die Produktivität mehrerer trophischer Ebenen des Nahrungsnetzes von Fließgewässern beeinflussen und damit auch wie diese Auswirkungen gemildert werden könnten. Diese Ergebnisse verdeutlichen die dringende Notwendigkeit, effektive und breite Gewässerrandstreifen zu erhalten oder zu errichten, um Sedimenteinträge durch Erosion- und Oberflächenabfluss zu verringern, sowie Einträge von Nährstoffen und Pestiziden zurückzuhalten, um eine verbesserte Vereinbarkeit von Landwirtschaft und Naturschutz zu erwirken. Diese Maßnahmen hätten eine positive Auswirkung auf Lebensraum- und Ressourcenvielfalt und schützen damit sowohl terrestrische als auch aquatische Ökosysteme und die damit verbundenen essentiellen Ökosystemdienstleistungen dieser Systeme.:Table of contents Table of contents 1 List of tables 5 List of figures 6 List of abbreviations and acronyms 8 Abstract 11 Zusammenfassung 14 1. General introduction 18 1.1 Forested headwater streams - the significance of aquatic-terrestrial coupling 18 1.2 Effects of agricultural land use on forested headwater streams 22 1.3 Integrating measures of ecosystem functioning in stream ecosystem assessment 24 1.4 Aims and objectives 28 1.5 Thesis outline 30 2. Chapter I: Agricultural land use alters temporal dynamics and the composition of organic matter in temperate headwater streams 31 2.1 Introduction 31 2.2 Methods 33 2.2.1 Study sites 33 2.2.2 Sampling of POM inputs and standing crops 37 2.2.3 Organic matter sample processing 37 2.2.4 Physical and chemical stream characteristics 38 2.2.5 C spiraling metrics 39 2.2.6 Litter decomposition 39 2.2.7 Data analyses 41 2.3 Results 43 2.3.1 Organic matter inputs 43 2.3.2 Benthic organic matter 46 2.3.3 Organic matter retention 52 2.3.4 Environmental drivers of BOM dynamics 55 2.3.5 Leaf litter decomposition 55 2.4 Discussion 57 2.4.1 Effects of agricultural land use on POM inputs and BOM dynamics 57 2.4.2 Organic matter retention 60 2.4.3 Organic matter processing 61 2.4.4 Ecosystem-level implications of altered OM dynamics 62 2.5 Conclusions 63 3. Chapter II: Biofilm-specific uptake does not explain differences in whole-stream DOC tracer uptake between a forest and an agricultural stream 64 3.1 Introduction 64 3.2 Methods 66 3.2.1 Site description 66 3.2.2 Stable isotope tDOC labeling 68 3.2.3 Experimental design 68 3.2.4 Sampling and analysis 69 3.2.5 Statistical analysis 72 3.3 Results 74 3.3.1 Stream characteristics 74 3.3.2 DOC uptake 75 3.3.3 Benthic biofilm attributes 79 3.4 Discussion 84 3.4.1 Mechanisms linking hydromorphology, benthic-biofilm uptake and whole-stream uptake 84 3.4.2 Comparison of whole-stream tDOC uptake with other studies 86 3.4.3 Benthic biofilm attributes 87 3.5 Conclusions 89 4. Chapter III: Resource supply and organismal dominance are associated with high secondary production in temperate agricultural streams 90 4.1 Introduction 90 4.2 Methods 93 4.2.1 Study sites 93 4.2.2 Macroinvertebrate sampling and processing 97 4.2.3 Macroinvertebrate secondary production (MSP) 97 4.2.4 Environmental characteristics of streams 98 4.2.5 Benthic organic matter 99 4.2.6 Biofilm biomass accrual and stoichiometry 99 4.2.7 Fish biomass 100 4.2.8 Ingestion rates and interaction strength 100 4.2.9 Data analyses 101 4.3 Results 104 4.3.1 Environmental characteristics of the study streams 104 4.3.2 Structural descriptors of the macroinvertebrate community 106 4.3.3 Macroinvertebrate secondary production (MSP) 107 4.3.4 Environmental drivers of MSP and biomass 109 4.3.5 Relationships between MSP and species richness and evenness 111 4.3.6 Consumer-resource interactions 111 4.4 Discussion 113 4.4.1 Environmental drivers of MSP and biomass 113 4.4.2 Biological mechanisms associated with MSP 116 4.4.3 Top-down vs. bottom-up control 118 4.5 Conclusion 120 5. General discussion 121 5.1 Environmental conditions 121 5.2 Allochthonous organic matter dynamics 122 5.3 Organic matter processing 124 5.4 Primary production 124 5.5 Drivers of macroinvertebrate secondary production 127 5.6 Fish community 128 6. General conclusion 132 7. Implications for the assessment of running water ecosystems 134 8. Outlook 137 References 139 Appendix 182 Chapter I 182 Chapter II 189 Supplemental methods 189 Chapter III 198 Acknowledgements 212 Curriculum vitae 215 List of publications 217 Publication output during thesis period 217 Further publications 218 Eidesstattliche Erklärung 219 / Intensive crop agriculture is one of the most ubiquitous and pervasive anthropogenic threats to aquatic ecosystems. Important agriculture-related pressures include riparian clearcutting and the associated loss of allochthonous organic matter inputs and shading, nutrient and pesticide contamination, fine sediment inputs due to erosion and run-off, increased surface runoff, flashier hydrographs as well as degraded geomorphology and habitat diversity. The multitude of stressors deriving from agricultural land use often produces concomitant effects on several groups of biological organism and associated functions. While effects on single ecosystem components such as macroinvertebrates, biofilm or fish fauna with primary focus on structural components or single ecosystem processes are well described, only few studies have compiled comprehensive data sets on how agriculture affects the functioning of the entire aquatic ecosystem and interactions among ecosystem components. Thus, this thesis aimed to fill this knowledge gap by comparing agricultural and forested reference streams regarding their physicochemical characteristics, organic matter standing stocks and inputs, primary production, organic carbon spiraling, DOC uptake rates as well as secondary production of macroinvertebrates and fish for a period of 12-17 months. Intensive agricultural land use had strong effects on the physico-chemistry of the studied headwater streams of the main study (two agricultural streams vs. two forested streams in the Harz mountains, Saxony-Anhalt). We ascertained specific conductivity values in agricultural streams that exceeded the ones measured in forested streams by an order of magnitude. Concentrations of dissolved inorganic nitrogen and soluble reactive phosphorus were on average four times higher and pH was on average one unit lower in agricultural streams than in forested streams. Water temperature was on average 3°C higher in agricultural streams and showed higher diurnal variations. Particulate organic matter (POM) inputs to forested streams were approx. 30-times higher than inputs into agricultural streams, and mean standing crops of total benthic organic matter (BOM) were significantly lower in agricultural streams than in forested streams. Agricultural streams had significantly higher standing crops of fine benthic organic matter (FBOM), but less coarse benthic organic matter (CBOM) than forested streams. While in forested streams temporal dynamics of organic matter standing stocks followed a seasonal pattern, variations were predominantly stochastic and influenced by anthropogenic activities such as stream margin mowing in agricultural streams. Also, the retention of POM was distinctly lower in agricultural compared to forested streams due to lower in-stream complexity and flashier hydrographs in agricultural streams indicating that agricultural streams are less efficient to retain organic matter, facilitating the loss of carbon to downstream sections of streams. Within the main study streams, biofilm accrual rates and chlorophyll a content were six and eight times higher, respectively, and biofilm N:P and C:P ratios were three times lower in agricultural than forested streams. In the dissolved organic carbon-uptake experiment (one agricultural stream vs. one forested stream), biofilm quality was similarly higher in the agricultural stream Hassel. Against expectations, the Hassel showed a higher level of heterotrophy than the forested stream Wormsgraben. However, the total and biofilm associated uptake of labeled leaf-leachate dissolved organic carbon (DOC) in the Hassel was six and two times higher than in the forested Wormsgraben, respectively. As the biofilm-specific uptake in the forested stream amounted to only 4% of the whole stream uptake, it seems that microbial-mediated processing of nutrients in the hyporheic zone is responsible for the largest proportion of DOC uptake. Presumably, the higher transient storage and the heterotrophic community resident in the interstitial pore space of the forested stream has a higher demand for labile DOC and hence, retained distinctly more DOC than in the agricultural stream, highlighting the importance of functional hyporheic zones for carbon spiraling. The macroinvertebrate community assessment revealed that species richness was reduced by half in agricultural compared to forested streams. Macroinvertebrate biomass, density, and secondary production (MSP), however, increased along a gradient of resource quality and quantity with highest productivity in the agricultural stream Sauerbach, followed by the agricultural stream Getel, and the forested streams Ochsenbach and Wormsgraben. The increase in MSP was mainly due to higher production within the functional feeding groups (FFGs) of gatherer/collectors and grazers. Higher MSP, biomass, and density correlated positively with lower biofilm N:P and C:P ratios and resource quantity (higher biofilm accrual rate and standing crops of riparian herbaceous vegetation, biofilm and seston chlorophyll a, total dissolved nitrogen, soluble reactive phosphorus, and particulate organic carbon concentrations). High interaction strengths between shredders and coarse particulate organic carbon (CPOM) in agricultural streams indicated a resource limitation of allochthonous organic matter, while this seemed to have no effect on macroinvertebrate productivity as interaction strengths between grazers and biofilm as well as between fine particulate organic carbon (FPOM) and gatherers were distinctly lower in agricultural than in forested streams. These findings show that the loss of riparian canopy and excess nutrient conditions homogenized ecological niches and favored highly productive non-insect generalist species with high feeding plasticity to switch flexibly between ubiquitous and stochastically available food resources. In addition, analyses of fish secondary production and interaction strengths between fish and their macroinvertebrate prey demonstrated that agriculture may cause a major shift in fish species community composition, resulting in a decline in fish top-down control on MSP. Overall, the presented results demonstrate that agriculture induces a shift from nutrient-limited forested headwaters dependent on detrital pathways and closely coupled to riparian subsidies with highly diverse macroinvertebrate communities to homogenous, nutrient contaminated and taxonomically simplified streams with high levels of autochthony. The simultaneous analysis of structural and functional indicators showed that agriculture affects structural measures of community composition such as species richness without major changes in process rates (similar level of macroinvertebrate secondary production in the agricultural stream Getel compared to forested streams) and that variability in function (organic matter retention, decomposition) does not automatically reflect the information provided by commonly assessed structural measures of communities. The results of this thesis clearly showed that a combination of multiple structural and functional indicators along the food web hierarchy is required to mechanistically understand how intensive agricultural land use affects stream ecosystems. For example, only the information on quality and quantity of primary production combined with structural and functional information on the macroinvertebrate community allowed to mechanistically understand how agricultural stressors affect the productivity of multiple trophic levels of the stream food web and thus, how these effects can be mitigated. Given that such mitigation measures would largely address excessive nutrient and sediment inputs, the loss of habitat heterogeneity and natural resource dynamics, the high relevance of riparian buffer zones known for their effective the retention of nutrients, erosional run-off and the provision of resource quantity and quality is evident. Consequently, there is an urgent need to preserve or restore effective riparian zones along stream networks aiding both terrestrial and aquatic ecosystems while integrating protection measures for other anthropogenic pressures such as habitat degradation and climate change.:Table of contents Table of contents 1 List of tables 5 List of figures 6 List of abbreviations and acronyms 8 Abstract 11 Zusammenfassung 14 1. General introduction 18 1.1 Forested headwater streams - the significance of aquatic-terrestrial coupling 18 1.2 Effects of agricultural land use on forested headwater streams 22 1.3 Integrating measures of ecosystem functioning in stream ecosystem assessment 24 1.4 Aims and objectives 28 1.5 Thesis outline 30 2. Chapter I: Agricultural land use alters temporal dynamics and the composition of organic matter in temperate headwater streams 31 2.1 Introduction 31 2.2 Methods 33 2.2.1 Study sites 33 2.2.2 Sampling of POM inputs and standing crops 37 2.2.3 Organic matter sample processing 37 2.2.4 Physical and chemical stream characteristics 38 2.2.5 C spiraling metrics 39 2.2.6 Litter decomposition 39 2.2.7 Data analyses 41 2.3 Results 43 2.3.1 Organic matter inputs 43 2.3.2 Benthic organic matter 46 2.3.3 Organic matter retention 52 2.3.4 Environmental drivers of BOM dynamics 55 2.3.5 Leaf litter decomposition 55 2.4 Discussion 57 2.4.1 Effects of agricultural land use on POM inputs and BOM dynamics 57 2.4.2 Organic matter retention 60 2.4.3 Organic matter processing 61 2.4.4 Ecosystem-level implications of altered OM dynamics 62 2.5 Conclusions 63 3. Chapter II: Biofilm-specific uptake does not explain differences in whole-stream DOC tracer uptake between a forest and an agricultural stream 64 3.1 Introduction 64 3.2 Methods 66 3.2.1 Site description 66 3.2.2 Stable isotope tDOC labeling 68 3.2.3 Experimental design 68 3.2.4 Sampling and analysis 69 3.2.5 Statistical analysis 72 3.3 Results 74 3.3.1 Stream characteristics 74 3.3.2 DOC uptake 75 3.3.3 Benthic biofilm attributes 79 3.4 Discussion 84 3.4.1 Mechanisms linking hydromorphology, benthic-biofilm uptake and whole-stream uptake 84 3.4.2 Comparison of whole-stream tDOC uptake with other studies 86 3.4.3 Benthic biofilm attributes 87 3.5 Conclusions 89 4. Chapter III: Resource supply and organismal dominance are associated with high secondary production in temperate agricultural streams 90 4.1 Introduction 90 4.2 Methods 93 4.2.1 Study sites 93 4.2.2 Macroinvertebrate sampling and processing 97 4.2.3 Macroinvertebrate secondary production (MSP) 97 4.2.4 Environmental characteristics of streams 98 4.2.5 Benthic organic matter 99 4.2.6 Biofilm biomass accrual and stoichiometry 99 4.2.7 Fish biomass 100 4.2.8 Ingestion rates and interaction strength 100 4.2.9 Data analyses 101 4.3 Results 104 4.3.1 Environmental characteristics of the study streams 104 4.3.2 Structural descriptors of the macroinvertebrate community 106 4.3.3 Macroinvertebrate secondary production (MSP) 107 4.3.4 Environmental drivers of MSP and biomass 109 4.3.5 Relationships between MSP and species richness and evenness 111 4.3.6 Consumer-resource interactions 111 4.4 Discussion 113 4.4.1 Environmental drivers of MSP and biomass 113 4.4.2 Biological mechanisms associated with MSP 116 4.4.3 Top-down vs. bottom-up control 118 4.5 Conclusion 120 5. General discussion 121 5.1 Environmental conditions 121 5.2 Allochthonous organic matter dynamics 122 5.3 Organic matter processing 124 5.4 Primary production 124 5.5 Drivers of macroinvertebrate secondary production 127 5.6 Fish community 128 6. General conclusion 132 7. Implications for the assessment of running water ecosystems 134 8. Outlook 137 References 139 Appendix 182 Chapter I 182 Chapter II 189 Supplemental methods 189 Chapter III 198 Acknowledgements 212 Curriculum vitae 215 List of publications 217 Publication output during thesis period 217 Further publications 218 Eidesstattliche Erklärung 219

Human disruption of climate, habitat, and ignition has altered the behavior of wildland fire at local to continental scales. In many regions, novel fire regimes are emerging that threaten to exceed the capacity for local management to protect human wellbeing and ecosystem function. Simultaneous changes in climate, species composition, and fire management have resulted in extreme fire behavior in many regions. For the Western United States, the emerging novel fire regime consists of more frequent, severe, and intense wildfires, with annual area burned by wildfire having doubled and high-severity wildfire area having increased 8-fold since the 1980s. The impacts of these increasing stresses in the Great Basin is especially pressing when combined with the many years of historically poor resource management. Here we complete a literature review of changing wildfire regimes globally (chapter 1) and a study of how the abiotic and biotic aspects of aquatic ecosystems stabilize after a megafire in the western United States (chapter 2).

Water management is facing a growing number of challenges in many river basins worldwide, as the equal distribution of the available water resources is increasingly influenced by several, uncertain climatic and anthropic pressures. Within the current and projected water scarcity and drought scenario, such issue represents even a greater challenge in those basins that have been massively regulated in the XX century, as water managers are asked to find balanced policies to stay ahead with multiple, interdependent and ever-increasing water-related requirements. In this context, water conflict has become a recurring problem, with the freshwater ecosystems becoming the sole providers of unbearable human water needs and experiencing a severe alteration of their natural renewability and ecological integrity. In fact, the concern of sustaining the freshwater ecosystems has evolved throughout the years, coming to the fore since the 1990s under the concept of "ecosystem services", defined as the multiple benefits that people obtain from ecosystems. With a high number of challenges still ahead for implementing such paradigm in real-world water management practices, few investigations inspect the long-term evolution of highly regulated basins, being vulnerable freshwater systems characterized by a profusion of ecosystem services in a context of complex management policies and changing anthropic and climatic pressures. We focus our attention on the highly interconnected Garda-Mincio system (Northern Italy), further broadening the results to the regulated basins of the European perialpine region. First, to examine the modification of the freshwater systems from their pristine to their regulated conditions, we carried out an extensive collection of daily hydro-meteorological data by consulting public online sources as well as digitizing historical data contained in hand-written documents. The resulting database, which represents a valuable source of long-term daily hydro-meteorological data for the Garda-Mincio system, additionally underscored the complexity of constructing and maintaining a consistent and up-to-date database within an inter-regional context. The collected data were then adopted to investigate the climatic and anthropogenic drivers that have progressively influenced water availability, the provision of the changing water demands and the trade-offs with the existing water ecosystem services over the last two centuries. Statistical analyses were performed to outline the evolution of the annual and seasonal trends of Lake Garda water levels and outflows over the period 1888-2020, discussing the role of the Salionze Dam operational rules (completed in 1951) as well as the influence of the main water needs of the downstream Mincio River basin (i.e. hydropower production, irrigation and fluvial ecosystem sustenance). The role of hydro-meteorological factors was assessed by implementing a water balance model for Lake Garda, the largest lake in Italy, over the period 1928-2020, performing uncertainty and sensitivity analyses on specific water balance components (i.e. over-lake evaporation and basin evapotranspiration). We then focus our analyses on the management of the hydraulic infrastructures that regulate the first and highly water-stressed stretch of the Mincio River downstream Lake Garda, i.e. the Salionze Dam and the Pozzolo-Marenghello infrastructures, where both high and low flow conditions reveal the inability of the current operational rules to support the new variety of water abstractions while maintaining appropriate environmental flow conditions and flood protection. These analyses were carried out through in-situ measurements and numerical simulations, updating the aging rating curves of the existing hydraulic infrastructures. Drawing on the Garda-Mincio system, we inspected the evolution of the freshwater regimes within the European perialpine lakes framework, discussing the outcomes to describe which common factors drove management policies in the area. Eventually, we discuss our outcomes recommending future sustainable and adaptive water management policies in the area.