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Monitoring Agricultural Land Use Intensity with Remote Sensing and Traits
No full textThe intensification of agricultural land use (A-LUI) is a central driver of global environmental change, affecting soil health, water quality, biodiversity, and greenhouse gas balances. Monitoring A-LUI remains challenging because it is shaped by multiple management practices, ecological processes, and spatio-temporal dynamics. This review provides a comprehensive synthesis of existing definitions and standards of A-LUI at national and international levels (FAO, OECD, World Bank, EUROSTAT) and evaluates in situ methods alongside the rapidly expanding potential of remote sensing (RS). We introduce a novel RS-based taxonomy of A-LUI indicators, structured into five complementary categories: trait, genesis, structural, taxonomic, and functional indicators. Numerous examples illustrate how traits and management practices can be translated into RS proxies and linked to intensity signals, while highlighting key challenges such as sensor limitations, cultivar variability, and confounding environmental factors. We further propose an integrative framework that connects management practices, plant and soil traits, RS observables, validation needs, and policy relevance. Emerging technologies—such as hyperspectral imaging, solar-induced fluorescence, radar, artificial intelligence, and semantic data integration—are discussed as promising pathways to advance the monitoring of A-LUI across scales. By compiling and structuring RS-derived indicators, this review establishes a conceptual and methodological foundation for transparent, standardised, and globally comparable assessments of agricultural land use intensity, thereby supporting both scientific progress and evidence-based agricultural policy.This research received no external funding.Peer Reviewe
Shrinking lakes, growing concerns: exploring perceptions of lake level decline as a prism for understanding socionatural hazards
No full textThe article processing charge was funded by the Open Access Publication Fund of Humboldt-Universität zu Berlin.Groß Glienicker Lake and Sacrower Lake are two lakes in the Berlin-Brandenburg region that are facing significant challenges due to declining water levels associated with climate change. In this paper, we report on a study that employed a mixed-method approach, incorporating ethnographic research, a household survey and stakeholder workshops, to address: (1) public and stakeholder perceptions of these declining lake levels (2) the social structures that interact with these perceptions, (3) the willingness to act and perceptions of responsibility, and (4) the local practices for dealing with these challenges. Our analysis reveals that lake level loss offers a prism through which such a hazard becomes visible and understandable as shaped by the interdependence of natural and social processes. From this understanding, we develop possible paths forward in governing risks adaptively. Such an expanded understanding of lake level loss as a socionatural hazard enables the orchestration of more comprehensive solutions to such phenomena than is possible solely on the basis of technical remedies to such hazards.Einstein Stiftung BerlinBerlin University AlliancePeer Reviewe
Genetic risk of obsessive-compulsive disorder and related psychiatric phenotypes - insights from large-scale genome-wide association studies
No full textDiese Arbeit untersucht das genetische Risiko von Zwangsstörungen sowie verwandten Merkmalen wie zwanghaften Symptomen, Hortungssymptomen und Tic-Störungen anhand großer genom-weiter Assoziationsstudien (GWAS).
Die erste Studie präsentiert die bislang größte GWAS zu Zwangsstörungen (53.660 Fälle, 2.044.417 Kontrollen) und identifizierte erstmals 30 unabhängige genomweit signifikante Loci sowie eine SNP-Heritabilität von 6,7 %. Insgesamt wurden 249 Risikogene gefunden, darunter 25 potenziell kausale. Funktionelle Analysen hoben hippocampale und kortikale exzitatorische Neuronen sowie medium spiny neurons hervor. Die zweite Studie untersuchte subklinische Zwangssymptome in 33.943 Personen. Obwohl keine signifikanten SNPs identifiziert wurden, zeigte sich eine SNP-Heritabilität von 4,1 % und eine starke genetische Überlappung mit Zwangsstörungen (genetische Korrelation: 72 %, p = 0,0007). Ein polygener Risikoscore für Zwangsstörungen war ebenfalls signifikant assoziiert, was ein Kontinuum von Symptomen und Erkrankung unterstützt. Die dritte Studie zu Hortungssymptomen (27.651 Personen) fand eine moderate Heritabilität (SNP-h² = 11 % in einer Kohorte) jedoch keine signifikanten SNPs. PRS-Analysen zeigten genetische Assoziationen mit Schizophrenie und Autismus, nicht aber mit Zwangsstörungen. Die vierte Studie erweiterte die GWAS zu Tic-Störungen (9.619 Fälle, 981.048 Kontrollen) und identifizierte einen genomweit signifikanten SNP (rs79244681) sowie drei Risikogene (BCL11B, NDFIP2, RBM26). Die Analysen unterstrichen die Rolle des kortiko-striato-thalamo-kortikalen Regelkreises und spezifischer neuronaler Zelltypen. Die Dissertation liefert neue Einblicke in das genetische Risiko von Zwangs- und Tic-Störungen sowie verwandten Symptomen und schafft eine Grundlage für präzisere Diagnosen und Therapien. Begrenzte Stichprobengrößen und die Überrepräsentation europäischer Abstammung bleiben zentrale Limitationen.This dissertation investigates the genetic risk of obsessive-compulsive disorder (OCD) as well as related traits such as obsessive-compulsive symptoms, hoarding symptoms, and tic disorders using large genome-wide association studies (GWAS). The first study presents the largest GWAS of OCD to date (53,660 cases, 2,044,417 controls) and for the first time identified 30 independent genome-wide significant loci as well as a SNP heritability of 6.7%. In total, 249 risk genes were identified, including 25 potentially causal ones. Functional analyses highlighted hippocampal and cortical excitatory neurons as well as medium spiny neurons. The second study examined subclinical obsessive-compulsive symptoms in 33,943 individuals. Although no genome-wide significant SNPs were identified, the SNP heritability was estimated at 4.1%, and there was substantial genetic overlap with OCD (genetic correlation: 72%, p = 0.0007). A polygenic risk score for OCD was also significantly associated, supporting a continuum between symptoms and clinical disorder. The third study on hoarding symptoms (27,651 individuals) found moderate heritability (SNP-h² = 11% in one cohort) but no genome-wide significant SNPs. PRS analyses revealed genetic associations with schizophrenia and autism, but not with OCD. The fourth study expanded the GWAS of tic disorders (9,619 cases, 981,048 controls) and identified one genome-wide significant SNP (rs79244681) as well as three risk genes (BCL11B, NDFIP2, RBM26). Analyses underscored the role of the cortico-striato-thalamo-cortical circuit and specific neuronal cell types. The dissertation provides new insights into the genetic risk of OCD, tic disorders, and related symptoms, and lays the groundwork for more precise diagnoses and therapies. Limited sample sizes and the overrepresentation of individuals of European ancestry remain key limitations
Essays on Financial Applications of Machine Learning
No full textMaschinelles Lernen ist zu einem unverzichtbaren Werkzeug für die Analyse und Modellierung von Finanzmärkten geworden. Diese kumulative Arbeit besteht aus drei Abschnitten zu diesem Thema. Der erste Abschnitt analysiert und prognostiziert das Handelsvolumen eines lokalen Kryptowährungsmarktes über einen Zeitraum von 4 Stunden mithilfe von LSTM mit früheren Transaktionsdaten, Renditedaten, Stimmung und makroökonomischen Daten. Der zweite Abschnitt modelliert sowohl einzelne Stromauktionsmärkte als auch deren Abhängigkeit mithilfe eines Distributional Multilayer Perceptron (DMLP). Das Modell wird dann verwendet, um Preise zu simulieren und eine flexible Gebotsstrategie basierend auf einer risikoadjustierten Anlegernutzenfunktion zu erstellen. Die Handelsanwendung nutzt die Unterschiede zwischen den beiden Börsen, indem sie an beiden Long/Short-Positionen hält. Der letzte Abschnitt führt Regime in ein Reinforcement-Learning-Modell ein, das für den automatisierten Handel mit Kryptowährungen entwickelt wurde. Die Regime werden durch die Analyse kryptowährungsspezifischer Daten wie Blockgröße, Hash-Rate oder Mining-Schwierigkeit zusätzlich zu den üblichen Metriken bestimmt.Machine learning has become an essential tool for the analysis and modeling of financial markets. This cumulative work consists of three individual sections on this topic. The first section analyzes and forecasts the trading volume of a local cryptocurrency market over a 4-hour time period using LSTM with previous transaction data, return data, sentiment, and macroeconomic data. The second section models both individual electricity auction markets and how they are interconnected using a distributional multilayer perceptron (DMLP). The model is then used to simulate prices and create a flexible bidding strategy based on a risk-adjusted investor utility function. The trading application leverages the differences between the two exchanges by having long/short positions in both. The final section introduces regimes to a reinforcement learning model designed for automated trading for cryptocurrencies. The regimes are determined by analyzing cryptocurrency-specific data, such as block size, hash rate, or mining difficulty, in addition to the usual metrics
The Role of Beaver Dams in Modulating Hydrological Connectivity and Nutrient Dynamics in Agricultural Catchments With Intermittent Streams
No full textBeaver dams and associated wetlands can significantly alter hydrological connectivity and biogeochemical processes in catchments, but their combined influence on nutrient dynamics remains understudied. This research investigated the combined effects of beaver‐impacted ditches and ponds on macronutrient (nitrogen (N), phosphorus (P), and carbon (C)) dynamics in an intermittent agricultural stream network. Building on long‐term catchment monitoring, this study provides the first spatially extensive, site‐scale assessment of nutrient dynamics across multiple water body types in this catchment, using comparisons between beaver dam impacted and non‐impacted sites across multiple water body types to infer beaver‐related effects under variable hydrological connectivity. Continuous monitoring of water presence and water levels across the stream network revealed distinct seasonal patterns of hydrological connectivity, which strongly influenced stream water quality. When hydrological connectivity was highest in the wet season, agricultural drainage elevated nitrate nitrogen (NO3‐N) concentrations, creating extreme stoichiometric imbalances. In contrast, during dry periods, as hydrological connectivity declined and the stream network became intermittent, beaver ditch‐pond complexes demonstrated significant capacity for nutrient mitigation through enhanced N removal, coupled with increased concentrations of soluble reactive phosphorus (SRP) and dissolved organic carbon (DOC). Beaver activity also contributed to maintaining hydrological connectivity and sustaining stream flows, prolonging the time for nutrient processing. Beaver‐related ponds and wetlands significantly reduced NO3‐N while elevating total P and DOC concentrations, resulting in a more balanced nutrient stoichiometry closely linked to hydrological connectivity. These findings demonstrate the potential effectiveness of beaver dams and associated wetlands as nature‐based solutions for agricultural nutrient management, though their benefits were most evident in spring and autumn when water fluxes are low and channel connectivity, supported by groundwater inputs, linked catchment nutrient inputs to the river. In addition, the impacts remain relatively localised, with downstream inputs from agricultural runoff rapidly offsetting benefits for catchment‐scale water quality.Deutsche Forschungsgemeinschaft 10.13039/501100001659Chinese Scholarship Council (CSC)Rüdiger Kurt Bode StiftungPeer Reviewe
High place phenomenon, obsessive-compulsive symptoms and suicidality
No full textBackground: The high place phenomenon (HPP), referring to a sudden urge to jump when standing in a high place, occurs frequently in both suicidal and non-suicidal individuals. Despite apparent similarities, researchers have not yet examined potential associations with obsessive-compulsive symptoms, nor has the phenomenon been explored in a non-Western society. Methods: The study comprises two samples of Iranian adults: An online sample including N = 257 participants (54% male; Mage=37.03, SDage= 11.51) and a sample of mobility impaired participants including N = 233 participants (56.2% male; Mage=37.84, SDage= 9.75, range: 18–68 years). All participants filled out questionnaires on experiences with the high place phenomenon, depression, suicidal ideation/behavior, anxiety sensitivity and obsessive-compulsive symptoms. Results: Between 39% and 62% of participants reported being familiar with the HPP. In both samples, obsessive-compulsive symptoms showed a significant association with the severity of the phenomenon, even after accounting for depression, suicidal ideation/behavior, and anxiety sensitivity. The presence of the HPP was only associated with obsessive-compulsive symptoms in one of the two samples. Conclusion: Findings point to the cross-cultural nature of the HPP. Furthermore, the association between obsessive-compulsive symptoms and the HPP speaks to a conceptualization of the HPP as being part of the phenomenological field of (subsyndromal) OCD symptoms.Peer Reviewe
Register-related dimensions of linguistic variation in Russian: a multidimensional analysis (MDA)
No full textDiese Dissertation untersucht registerbezogene Dimensionen sprachlicher Variation im Russischen mithilfe der Multidimensionalen Analyse (MDA). Register wird dabei als konventionalisierte und wiederkehrende linguistische Muster intraindividueller Variation verstanden, die durch situativ-funktionale Parameter beeinflusst werden (Pescuma et al., 2023). Die zentrale Forschungsfrage lautet: Welche Variationsdimensionen lassen sich auf Grundlage der Kookkurrenzmuster linguistischer Merkmale in einem russischen Korpus identifizieren? Zunächst wird das Registerkonzept aus drei theoretischen Perspektiven beleuchtet: der variationslinguistischen, der systemisch-funktionalen und der textlinguistischen. Anschließend wird Register von verwandten Konzepten wie Genre, Stil, Textsorte und funktionalem Stil abgegrenzt. Anschließend wird die MDA vorgestellt, die auf dem RuMorS+-Korpus basiert und sowohl gesprochene als auch geschriebene russische Texte aus den Jahren 1950 bis 2022 umfasst. Die Analyse von116 linguistischen Merkmale identifiziert fünf Dimensionen sprachlicher Variation, interpretiert als spontan – vorbereitet, elaboriert – informational, deskriptiv – narrativ, hoher – niedriger Kohäsionsgrad sowie abstrakt – konkret. Die ersten beiden Dimensionen werden mit entsprechenden Dimensionen in MDAs des Englischen und des Tschechischen verglichen, wodurch sowohl strukturelle Parallelen als auch Unterschiede sichtbar werden. Darüber hinaus wird die mögliche Universalität bestimmter dimensionsübergreifender Tendenzen diskutiert. Die Arbeit stellt die erste registerbezogene MDA des Russischen dar, die auf einem Korpus mit breitem Spektrum situativ-funktionaler Parameter basiert. Sie leistet einen Beitrag zur quantitativen Registerforschung und zeigt, dass sich sowohl universale Muster sprachlicher Variation als auch russischspezifische Ausprägungen identifizieren lassen.This PhD thesis investigates register-related dimensions of linguistic variation in Russian by applying Multidimensional Analysis (MDA). It adopts a definition of register as those conventionalized and recurrent linguistic patterns of intra-individual variation within a speech community that are influenced by situational-functional parameters (Pescuma et al., 2023). The central research question of the study is: What dimensions of linguistic variation can be identified based on the co-occurrence patterns of linguistic features within texts of a Russian corpus? First, the thesis explores the concept of register as a form of intra-individual linguistic variation from the perspectives of three frameworks: variationist linguistics, systemic functional linguistics, and text linguistics. Second, it situates register among related concepts of linguistic variation – genre, style, text type, and functional style. Finally, it presents the MDA conducted on the RuMorS+ corpus, comprising both spoken and written Russian texts from 1950 to 2022. The analysis identifies co-occurrence patterns among 116 linguistic features, establishing five dimensions of linguistic variation, interpreted as spontaneous – prepared, elaborated – informational, descriptive – narrative, higher – lower degree of cohesion, and abstract – concrete. The first two dimensions are compared to corresponding ones in MDAs of English and Czech, revealing both parallels and differences in their structure. The discussion further addresses the potential universality of certain dimensions. The study presented in this thesis represents the first register-related MDA of Russian based on a corpus that covers a broad range of situational-functional parameters, thereby contributing to the tradition of quantitative register analysis. The identified dimensions of linguistic variation support the notion of universal tendencies in language variation while also capturing Russian-specific dimensional characteristics
Selfhood-attribution in a social context: further evidence for a Pars-Pro-Toto account
No full textIntroduction: Humans show a consistent tendency to anthropomorphize or attribute aspects of selfhood to non-human agents. In a previous study, we found that people (over-)generalize from the presence of a single behavioral selfhood cue (like equifinality or efficiency) to the presence of other (actually absent) cues, suggesting that a small aspect of selfhood suffices to activate the entire selfhood concept with all its other implications (Pars-Pro-Toto). Method: Our previous study was exclusively manipulating non-social aspects of selfhood. However, the contribution of social interaction in developing a concept of “Self” has been stressed in the literature. Thus, in the present study we tested whether these findings can also be demonstrated for social aspects. Specifically, we manipulated the presence or absence of cues indicating social sensitivity, attention sharing, or helping behavior in small non-humanoid robots, and tested which cues would elicit attributions of various aspects of selfhood. Results: The results replicated our previous finding that the presence of a single cue is sufficient to (over-)generalize to other, non-manipulated cues, extended our previous observations to social conditions and provided further support for our Pars-Pro-Toto account. It is noteworthy that participants showed a stronger tendency to overgeneralize to other social selfhood-related characteristics than to the non-social characteristics. Moreover, compared to our previous study, participants no longer showed a consistently stronger attribution of agency to the robot that was exhibiting cues for one of the critical characteristics. Discussion: The missing effects of agency are discussed as reflecting how sociality might be construed vis-à-vis individual goal pursuit. The interplay between sociality and individuality might be linked to our perception of agency in other agents when these are part of a group. The results are further discussed in light of the increasing presence of robots and other artificial agents in everyday life, as they support a shift in focus from their actual capabilities toward what people's expectations of these systems are. We stress that it is important to consider technological systems in their social relation to people as they tend to attribute complex concepts such as selfhood even when only perceiving simple behavioral cues.Peer Reviewe
A SWOT-AHP analysis of stakeholders’ perceptions and its impact on the quality of Amaranth and African nightshade
No full textThe article processing charge was funded by the Open Access Publication Fund of Humboldt-Universität zu Berlin.High postharvest losses of African indigenous vegetables (AIVs) like amaranth and African nightshade limit both their availability for consumption and processing. Evaporative cold storage is proposed to address these losses in rural areas. A mixed-method approach was used. This included a qualitative strengths, weaknesses, opportunities, threats, and analytical hierarchy process (SWOT-AHP) evaluation, as well as experimental studies on the impact of evaporative charcoal coolers and brick coolers on vegetable quality. Overall, AIV value chain stakeholders perceived evaporative cold storage as highly necessary, given the expected benefit of reducing postharvest losses as AIV production increases. Its perceived main strengths were: maintaining vegetable quality, extending shelf-life, and the possibility to operate without electricity. However, knowledge of its establishment and operation, dependence on environmental conditions, high labour input, and potential user conflicts are key weaknesses and threats to be addressed. Compared to ambient conditions, temperature reduction (2.0 °C–8.5 °C and 2.4 °C–11.2 °C), and relative humidity increase (15.5 %–47.1 % and 10.3 %–49.3 %) were attained in the evaporative charcoal cooler and brick coolers, respectively. Fresh weight loss was reduced by 75.2 % and 64.0 % for amaranth, and by 72.8 % and 64.7 % for African nightshade in the charcoal and brick coolers, respectively, enabling shelf-life extension from 3 to 6 days. Nutritionally, proteins, minerals (Ca, P, K, Mg, Fe, Zn), and bioactive compounds such as total phenolic acids and flavonoids were maintained during evaporative cold storage. In conclusion, first, the SWOT-AHP analysis can guide the design and support the adoption of evaporative cold storage technologies, and second, evaporative coolers are viable options for maintaining quality and reducing postharvest losses of perishable crops such as African nightshade and amaranth in rural regions.Peer Reviewe
The power of storytelling: how narratives shape marine conservation and uses along the German coast of the Baltic Sea
No full textThe intensification of marine uses presents major challenges for the governance and conservation of marine spaces. This is particularly evident in the Baltic Sea, one of the most heavily impacted marine regions globally. In Schleswig–Holstein, Germany, a proposal to establish a national park along its coastline sparked considerable opposition, turning the public debate into a battleground of competing narratives. Proponents portrayed the national park as a solution to the environmental problems of the Baltic Sea, while opponents pushed narratives that fuelled fears of losing access to marine areas and livelihoods that quickly dominated the debate. Ultimately, the national park proposal was abandoned. This study applies the Narrative Policy Framework to analyse narratives used in the discourse surrounding the national park proposal based on 224 articles from two regional newspapers. One key finding is the strategic use of narrative characters in shaping the debate. Proponents cast the Baltic Sea as a victim of environmental degradation, while opponents portrayed local stakeholders as victims harmed by politicians as villains. Both groups shared an anthropocentric belief system, prioritising human interests over environmental concerns, posing a likely barrier to effective marine conservation. The national park debate serves as a microcosm of the general tensions between ecological protection and economic growth, reflecting the challenges of governing the Baltic Sea amidst growing industrialisation. The case demonstrates that marine conservation presents not only technical or ecological challenges in its execution but also challenges in crafting persuasive narratives to motivate action.Open Access funding enabled and organized by Projekt DEAL.Bundesministerium für Bildung und Forschunghttp://dx.doi.org/10.13039/501100002347Humboldt-Universität zu Berlin (1034)Peer Reviewe