Hidden miners - The role of microorganisms under cover crops for phosphorus management

Phosphorus (P) is a limiting and non-renewable nutrient for which improper management is becoming a threat to food security and an environmental hazard for aquatic ecosystems. Phosphorus is particularly difficult to manage as complex physicochemical processes in the soil leave most P unavailable for crop uptake. Cover crops are a promising tool of agronomic management, which may increase P availability for the following crops through various mechanisms, such as an overall extended root system, greater P mobilization via exudation of organic anions, enhanced P mineralization by phosphatase excretion and microbial interactions. Better understanding of plant-microbial interactions offer the possibility to unravel the potential of cover crops for P management. In the frame of the EU Horizon2020 Project SoilCare we present the results of two studies in SW Germany about P dynamics under cover crops. The first field experiment investigated the effects of cover crop mixtures and no-tillage in a field experiment in the research station Tachenhausen of Nuertingen-Geislingen University, the second one studied the effects of single cover crop species in a low-P field near Rottenburg. The samples were analyzed for PLFA/NLFA content, enzymatic activities (acid and alkaline phospho-monoesterases and phosphodiesterase) and microbial P. The results reveal significant effects of cover crop mixtures on soil microbes, increasing their abundance and activity, as well as shifts in the microbial community structure. The effects were more pronounced near the soil surface and were still detectable more than one year after cover cropping in winter wheat. The microbial abundance, including Pmic and the activity of several enzymes of the P cycle were strongly increased in the rhizosphere of the cover crops. The results indicate that, under optimized agronomic management, the use of cover crops and minimum tillage can have measurable positive effects on the cycling of P in temperate agroecosystems

Einfluss der Bodenbearbeitung nach mehrjährigem Leguminosen-Grasgemengeanbau auf die N-Mineralisierung unter den Bedingungen des Organischen Landbaus

Winterweizen wurde in den Jahren 1999 und 2000 an zwei Standorten in Süddeutschland, bearbeitet nach den Methoden des organischen Landbaus, nach dreijähriger Leguminose-Grasgemengevorfrucht angebaut. Die Bodenbearbeitung varrierte vor Aussaat in Intnsität, Zeit und Tiefe. Die Bodenbearbeitung hatte einen signifikanten Einfluß auf die N-Mineralisation. Die beiden Standorte zeigten unterschiedliche Ergebnisse

Teaching this class drives me nuts! - Examining the Person and Context Specificity of Teacher Emotions

Teachers' emotions are critically important for the quality of classroom instruction, and they are key components of teachers' psychological well-being. Past research has focused on individual differences between teachers, whereas within-teacher variation across contexts has rarely been considered. As such, the present research addresses the long-standing yet unresolved person-situation debate pertaining to the emotional experiences of teachers. In two diary studies (N = 135, 70% female, and N = 85, 28% female),we examined the role of person, academic subject, and group of students for teacher emotions;focusing on three of the most salient emotions found in teachers: enjoyment, anger, and anxiety. Findings from multi-level analysis confirmed the person specificity of enjoyment, anger, and, in particular, anxiety. In addition, underscoring the existence of within-teacher variability, findings supported that teachers' emotions considerably varied depending on the subject and group of students taught, particularly so for enjoyment and anger. Implications of the person and context specificity of teacher emotions are discussed in relation to assessments and intervention programs aiming to improve teachers' emotional lives in the classroom

Do Girls Really Experience More Anxiety in Mathematics?

Two studies were conducted to examine gender differences in trait (habitual) versus state (momentary) mathematics anxiety in a sample of students (Study 1: N = 584; Study 2: N = 111). For trait math anxiety, the findings of both studies replicated previous research showing that female students report higher levels of anxiety than do male students. However, no gender differences were observed for state anxiety, as assessed using experience-sampling methods while students took a math test (Study 1) and attended math classes (Study 2). The discrepant findings for trait versus state math anxiety were partly accounted for by students' beliefs about their competence in mathematics, with female students reporting lower perceived competence than male students despite having the same average grades in math. Implications for educational practices and the assessment of anxiety are discussed

Types of boredom: an experience sampling approach

The present study investigated different types of boredom as proposed in a four-categorical conceptual model by Goetz and Frenzel (2006; doi:10.1026/0049-8637.38.4.149). In this model, four types of boredom are differentiated based on degrees of valence and arousal: indifferent, calibrating, searching, and reactant boredom. In two studies (Study 1: university students, N = 63, mean age 24.08 years, 66 % female; Study 2: high school students, grade 11, N = 80, mean age 17.05 years, 58 % female), real-time data were obtained via the experience-sampling method (personal digital assistants, randomized signals). Boredom experiences (N = 1,103/1,432 in Studies 1/2) were analyzed with respect to the dimensions of valence and arousal using multilevel latent profile analyses. Supporting the internal validity of the proposed boredom types, our results are in line with the assumed four types of boredom but suggest an additional, fifth type, referred to as “apathetic boredom.” The present findings further support the external validity of the five boredom types in showing differential relations between the boredom types and other affective states as well as frequency of situational occurrence (achievement contexts vs. non-achievement contexts). Methodological implications as well as directions for future research are discussed

Analyse und Bewertung zu Stand und Entwicklungsmöglichkeiten von Futterbau und Tierernährung im ökologischen Landbau - Themenbezogenes Netzwerk Tierernährung im Ökologischen Landbau

Das Ziel des Vorhabens war es, ein Netzwerk zum Thema „Futterbau und Tierernährung im Ökologischen Landbau“ zu etablieren. Es soll dazu dienen, Fachleute aus der landwirtschaftlichen Praxis, der Beratung und der Forschung zu verbinden, um einen Wissensaustausch zu ermöglichen und durch inter- und transdisziplinäre Diskussionen Entwicklungsperspektiven aufzuzeigen. Zur detaillierten Analyse und Bewertung der Problematik wurden Arbeitsgruppen gebildet, die für die Bereiche Rinder-, Schweine- und Geflügelfütterung jeweils den Handlungsbedarf aufzeigen und Lösungsansätze für die bedarfsgerechte Versorgung dieser Nutztiere insbesondere im Hinblick auf die Umsetzung der 100 % Biofütterung erarbeiten sollten. Ergänzend dazu wurde eine umfangreiche Literaturrecherche und Schwachstellenanalyse durchgeführt. Die Steuerungsgruppe als zentrales Organ legte die Arbeitsweise des Netzwerks fest und gab die Inhalte vor, die als Grundlage für Diskussionen und wissenschaftliche Auseinandersetzungen dienen sollten. Sie wirkte beratend bei der Ausarbeitung der Schwachstellenanalyse mit und formulierte die Ziele des im Rahmen des Projektes durchgeführten Workshops. Die Koordination des gesamten Vorhabens oblag dem Zentrum Landwirtschaft und Umwelt der Universität Göttingen. Auf einem Workshop im März 2007 wurden die Ergebnisse der Netzwerkarbeit vorgestellt und mit Experten aus Wissenschaft, Beratung und Praxis diskutiert und bewertet. Empfehlungen für Futterbau und Tierernährung im ökologischen Landbau wurden differenziert nach Umsetzungs- und Forschungsbedarf formuliert. Zusätzlich wurden die Ergebnisse in der Zeitschrift „Ökologie und Landbau“ in Form eines Sonderheftes publiziert und so einer breiten landwirtschaftlichen Fachöffentlichkeit zugänglich gemacht. Die Arbeit im Netzwerk hat sich als effiziente Methode erwiesen, vorhandenes Wissen zwischen und innerhalb der einzelnen Disziplinen und Institutionen zu transferieren und zu bündeln. Sie sollte im Interesse aller Beteiligten weitergeführt werden, um den wissenschaftlichen Austausch weiter zu entwickeln und für Kooperationen in der Forschung, aber auch zwischen Praxis und Forschung zu nutzen

Excessive boredom among adolescents: A comparison between low and high achievers

Existing research shows that high achievement boredom is correlated with a range of undesirable behavioral and personality variables and that the main antecedents of boredom are being over- or under-challenged. However, merely knowing that students are highly bored, without taking their achievement level into account, might be insufficient for drawing conclusions about students' behavior and personality. We, therefore, investigated if low- vs. high-achieving students who experience strong mathematics boredom show different behaviors and personality traits. The sample consisted of 1,404 German secondary school students (fifth to 10th grade, mean age 12.83 years, 52% female). We used self-report instruments to assess boredom in mathematics, behavioral (social and emotional problems, positive/negative affect, cognitive reappraisal, and expressive suppression), and personality variables (neuroticism and conscientiousness). In comparing highly bored students (more than one SD above M, n = 258) who were low vs. high achievers (as indicated by the math grade, n = 125 / n = 119), results showed that there were no mean level differences across those groups for all variables. In conclusion, our results suggest that high boredom can occur in both low- and high-achieving students and that bored low- and high-achievers show similar behaviors and personality profiles

Emotion and performance

The study of emotions in organizational settings has attained considerable prominence in recent years, but I critical issue remains unresolved. This is the relationship between emotion and performance. in this special issue, 5 articles address this topic from a variety of viewpoints. Two are theoretical essays that deal, respectively, with emotion and creativity and the relationships between individual and team performance. Three are empirical studies that canvass the emotion-performance nexus across levels of analysis: within person, between persons, and in groups. Between them, the 5 articles present a strong case for the nexus of emotions and performance, but, more important, they provide a platform for potentially fruitful future research in this burgeoning area

School grades and students’ emotions: Longitudinal models of within-person reciprocal effects

Based on control-value theory, we expected reciprocal associations between school grades and students' achievement emotions. Existing research has employed between-person designs to examine links between grades and emotions, but has failed to analyze their within-person relations. Reanalyzing data used by Authors (2017) for between-person analysis, we investigated within-person relations of students’ grades and emotions in mathematics over 5 school years (N = 3,425 German students from the PALMA longitudinal study; 50.0% female). The findings from random-intercept cross-lagged modeling show that grades positively predicted positive emotions within persons over time. These emotions, in turn, positively predicted grades. Grades were negative predictors of negative emotions, and these emotions, in turn, were negative predictors of grades. The within-person effects were largely equivalent to between-person relations of grades and emotions. Implications for theory, future research, and educational practice are discussed