298 research outputs found
Programming rural development funds – An interactive linear programming approach applied to the EAFRD program in Saxony-Anhalt
Policies for rural areas have become an important but complex policy field in the European Union`s Common Agricultural Policy. The purpose of this paper is to report on a methodological approach pursued to model the allocation of EAFRD (European Agricultural Fund for Rural Development) funds in Saxony-Anhalt. We show how an interactive programming approach can be developed and used to support our partner Ministry of Agriculture and the Environment. So far, various key elements of the modeling approach have been specified: the definition of all relevant policy measures and funding options, the assessment of impacts on the regional objectives pursued, the definition of relevant lower and upper bounds, and the formulation of co-financing requirements and possibilities. Some first results reveal potentials for policy adjustment. After some more refinements and specifications, the model is to be used interactively with Ministry representatives for scenario calculations to support policy-making and strategy development for rural development in Saxony-Anhalt.rural development, interactive programming, EAFRD, multi-level co-financing, Saxony-Anhalt, Agricultural and Food Policy, Agricultural Finance, Community/Rural/Urban Development, Environmental Economics and Policy, Institutional and Behavioral Economics, Public Economics,
Social dimensions of multifunctional agriculture in Europe - towards an interdisciplinary framework
Agriculture is embedded in and interacts with both its ecological and social environments. Under the concept of ‘Multifunctional Agriculture’, these interactions receive attention from scientific and political communities in terms of societal functions that can be fulfilled by farms. The discourse has focused on ecological functions, while agriculture’s social contributions are frequently mentioned but not systematically addressed. Accordingly, respective empirical results remain fragmented and applied conceptual approaches barely integrated. To address this research gap, we conducted a systematic literature review on the social functions of European agriculture. Our analysis (a) disentangles different definitions and categorizations of social functions found in the literature; (b) proposes an interdisciplinary framework and categorization that eases the linkage of relevant insights from different conceptual viewpoints; and (c) paves the way for the differentiated recognition and governance of the diverse social functions potentially delivered by farms and their activities in the European context.Peer Reviewe
Was bringt Stationenlernen im RW - Unterricht? Eine experimentelle Studie zu Lernmotivation und Lernerfolg
Der Gegenstand Rechnungswesen bereitet vielen Lernenden Schwierigkeiten. Gleichzeitig wird der Rechnungswesenunterricht häufig als eintönig und langweilig empfunden, nicht zuletzt auch deshalb, weil lehrendenzentrierte Unterrichtsformen dominieren. In diesem Beitrag wird daher der Frage nachgegangen, inwiefern Lernmotivation und Lernerfolg in Rechnungswesen durch den Einsatz von Stationenlernen verbessert werden können. Diese im Bereich der Volksschule und Sekundarstufe I verbreitete Unterrichtsmethode wird in der Sekundarstufe II und im Tertiären Bereich nur selten einge-setzt und ist kaum erforscht. Vor diesem Hintergrund haben die Autor/inn/en im Wintersemester 2017/18 im Rahmen einer Lehrveranstaltung im ersten Semester des Masterprogramms für Wirtschaftspädagogik an der WU Wien ein Unterrichtsexperiment zum Vergleich von traditionellem Frontalunterricht und Stationenlernen durchgeführt. Zwei der drei parallel laufenden Lehrveranstal-tungsgruppen wurden als Experimentalgruppe und eine als Kontrollgruppe geführt. Unterrichtet wur-den vier Themen aus dem Bereich der Doppelten Buchhaltung. In allen Gruppen wurden die Motivation im Zeitablauf und der Lernzuwachs durch einen Pre- und Posttest gemessen. Jeweils am Ende der Lehrveranstaltung wurde ein Fragebogen zur Evaluation der Unterrichtsmethode eingesetzt. Zudem wurden die Aktivitäten der Lehrenden und der Lernenden beobachtet. Insgesamt zeigten sich weder hinsichtlich Lernmotivation noch hinsichtlich Lernerfolg signifikante Unterschiede. Detailliertere quantitative und qualitative Analysen geben jedoch Hinweise für einen effizienten Einsatz von Statio-nenlernen im Rechnungswesenunterricht
Plant diversity and community history shift colonization success from early- to mid-successional species
Aims Functional traits are supposed to play an important role in determining the colonization success of new species into established communities. Short-term experimental studies have documented higher resistance of more diverse grasslands against colonization by new species. However, little is known about which traits colonizers should have to successfully invade diverse plant communities in the longer term and how community history may modify the resistance of diverse communities against colonization. Methods In a grassland biodiversity experiment (Jena Experiment) established with different species richness (SR; 1, 2, 4, 8 and 16) and functional group (FG) number and composition (1 to 4; legumes, grasses, small herbs, tall herbs), we studied colonization of naturally dispersed species in split-plots (i) with different duration of weeding (never weeded, weeded for 3 or 6 years and then un-weeded for 1 year) and (ii) with different duration of colonization (7 years, 4 years and 1 year after cessation of weeding). Important Findings Resistance against colonization by new species declined with increased duration of weeding (on average 13, 17 and 22 colonizer species in 1-, 4- and 7-year-old communities, respectively). Communities established at low diversity accumulated more colonizer species with a longer duration of weeding than more diverse communities. Duration of colonization had only small effects on the number of colonizer species. Colonizers with early successional traits, i.e. annual life cycle, reproduction by seeds, small seeds, long-lived seeds and an earlier start of a longer flowering period, were favoured in species-poor newly established experimental plant communities (short duration of weeding) and early after cessation of weeding (short duration of colonization). A change from early- to mid-successional traits, i.e. taller growth, perennial life cycle, vegetative reproduction, characterized colonization at increased plant diversity and in communities with legumes or without grasses. Legume absence/grass presence and increased duration of weeding led to a shift in colonizer strategies from rapid nutrient uptake and cycling (higher specific leaf area) to nutrient retention and symbiotic N2 fixation. Our study shows that non-random trait spectra of naturally dispersed colonizers encompass trade-offs between different functions (reproduction, persistence, growth) reflected in a change from early- to mid-successional traits at increasing plant diversity, with a longer duration of weeding and a longer time of colonizatio
ADHD symptoms in adolescents\u27 everyday life. Fluctuations and symptom structure within and between individuals
This study investigated whether self-reported ADHD symptoms fluctuate substantially within adolescents from day to day, and examined the underlying symptom factor structure on a within- and between-person level. Method: Adolescents (N = 166) rated their ADHD symptoms over the phone on eight consecutive evenings (total ratings: n = 1,264). Results: ADHD symptoms showed substantial fluctuations within adolescents from day to day, as indicated by within-person standard deviations and intraclass correlation coefficients. Both a two-level factor model with three correlated factors (inattention, hyperactivity, impulsivity) and a two-level bifactor model with a general ADHD symptom factor and a specific inattention factor provided acceptable to good accounts of the structure underlying daily ADHD symptom ratings on the between- and the within-person level. Conclusion: The study demonstrates that adolescents\u27 ADHD symptoms fluctuate from day to day and highlights the need for intensive diagnostic processes with repeated symptom assessments and interventions that address symptom fluctuations. (DIPF/Orig.
Differential effects of plant diversity on functional trait variation of grass species
Background and Aims Functional trait differences and trait adjustment in response to influences of the biotic environment could reflect niche partitioning among species. In this study, we tested how variation in above-ground plant traits, chosen as indicators for light and nitrogen acquisition and use, differs among taxonomically closely related species (Poaceae) to assess their potential for niche segregation at increasing plant diversity. Methods Traits of 12 grass species were measured in experimental grasslands (Jena Experiment) of varying species richness (from 1 to 60) and presence of particular functional groups (grasses, legumes, tall herbs and small herbs). Key Results Grass species increased shoot and leaf length, investment into supporting tissue (stem mass fraction) and specific leaf area as well as reduced foliar δ13C values with increasing species richness, indicating higher efforts for light acquisition. These species-richness effects could in part be explained by a higher probability of legume presence in more diverse communities. Leaf nitrogen concentrations increased and biomas s : N ratios in shoots decreased when grasses grew with legumes, indicating an improved nitrogen nutrition. Foliar δ15N values of grasses decreased when growing with legumes suggesting the use of depleted legume-derived N, while decreasing δ15N values with increasing species richness indicated a shift in the uptake of different N sources. However, efforts to optimize light and nitrogen acquisition by plastic adjustment of traits in response to species richness and legume presence, varied significantly among grass species. It was possible to show further that trait adjustment of grass species increased niche segregation in more diverse plant communities but that complementarity through niche separation may differ between light and nutrient acquisition. Conclusions The results suggest that even among closely related species such as grasses different strategies are used to cope with neighbours. This lack in redundancy in turn may facilitate complementary resource use and coexistenc
Cryptochrome-dependent and -independent circadian entrainment circuits in Drosophila.
Entrainment to environmental light/dark (LD) cycles is a central function of circadian clocks. In Drosophila, entrainment is achieved by Cryptochrome (CRY) and input from the visual system. During activation by brief light pulses, CRY triggers the degradation of TIMELESS and subsequent shift in circadian phase. This is less important for LD entrainment, leading to questions regarding light input circuits and mechanisms from the visual system. Recent studies show that different subsets of brain pacemaker clock neurons, the morning (M) and evening (E) oscillators, have distinct functions in light entrainment. However, the role of CRY in M and E oscillators for entrainment to LD cycles is unknown. Here, we address this question by selectively expressing CRY in different subsets of clock neurons in a cry-null (cry0) mutant background. We were able to rescue the light entrainment deficits of cry0 mutants by expressing CRY in E oscillators but not in any other clock neurons. Par domain protein 1 molecular oscillations in the E, but not M, cells of cry0 mutants still responded to the LD phase delay. This residual light response was stemming from the visual system because it disappeared when all external photoreceptors were ablated genetically. We concluded that the E oscillators are the targets of light input via CRY and the visual system and are required for normal light entrainment
Different assembly processes drive shifts in species and functional composition in experimental grasslands varying in sown diversity and community history
Background: The prevalence of different biotic processes (limiting similarity, weaker competitor exclusion) and historical contingency due to priority effects are in the focus of ongoing discussions about community assembly and non-random functional trait distributions.
Methodology/Principal Findings: We experimentally manipulated assembly history in a grassland biodiversity experiment (Jena Experiment) by applying two factorially crossed split-plot treatments to all communities: (i) duration of weeding (never weeded since sowing or cessation of weeding after 3 or 6 years); (ii) seed addition (control vs. seed addition 4 years after sowing). Spontaneous colonization of new species in the control treatment without seed addition increased realized species richness and functional richness (FRic), indicating continuously denser packing of niches. Seed addition resulted in forced colonization and increased realized species richness, FRic, functional evenness (FEve) and functional divergence (FDiv), i.e. higher abundances of species with extreme trait values. Furthermore, the colonization of new species led to a decline in FEve through time, suggesting that weaker competitors were reduced in abundance or excluded. Communities with higher initial species richness or with longer time since cessation of weeding were more restricted in the entry of new species and showed smaller increases in FRic after seed addition than other communities. The two assembly-history treatments caused a divergence of species compositions within communities originally established with the same species. Communities originally established with different species converged in species richness and functional trait composition over time, but remained more distinct in species composition.
Conclusions/Significance: Contrasting biotic processes (limiting similarity, weaker competitor exclusion) increase functional convergence between communities initially established with different species. Historical contingency with regard to realized species compositions could not be eradicated by cessation of weeding or forced colonization and was still detectable 5 years after application of these treatments, providing evidence for the role of priority effects in community assembly
Plant diversity and community history shift colonization success from early- to mid-successional species
Aims Functional traits are supposed to play an important role in determining the colonization success of new species into established communities. Short-term experimental studies have documented higher resistance of more diverse grasslands against colonization by new species. However, little is known about which traits colonizers should have to successfully invade diverse plant communities in the longer term and how community history may modify the resistance of diverse communities against colonization.
Methods In a grassland biodiversity experiment (Jena Experiment) established with different species richness (SR; 1, 2, 4, 8 and 16) and functional group (FG) number and composition (1 to 4; legumes, grasses, small herbs, tall herbs), we studied colonization of naturally dispersed species in split-plots (i) with different duration of weeding (never weeded, weeded for 3 or 6 years and then un-weeded for 1 year) and (ii) with different duration of colonization (7 years, 4 years and 1 year after cessation of weeding).
Important Findings Resistance against colonization by new species declined with increased duration of weeding (on average 13, 17 and 22 colonizer species in 1-, 4- and 7-year-old communities, respectively). Communities established at low diversity accumulated more colonizer species with a longer duration of weeding than more diverse communities. Duration of colonization had only small effects on the number of colonizer species. Colonizers with early successional traits, i.e. annual life cycle, reproduction by seeds, small seeds, long-lived seeds and an earlier start of a longer flowering period, were favoured in species-poor newly established experimental plant communities (short duration of weeding) and early after cessation of weeding (short duration of colonization). A change from early- to mid-successional traits, i.e. taller growth, perennial life cycle, vegetative reproduction, characterized colonization at increased plant diversity and in communities with legumes or without grasses. Legume absence/grass presence and increased duration of weeding led to a shift in colonizer strategies from rapid nutrient uptake and cycling (higher specific leaf area) to nutrient retention and symbiotic N2 fixation. Our study shows that non-random trait spectra of naturally dispersed colonizers encompass trade-offs between different functions (reproduction, persistence, growth) reflected in a change from early- to mid-successional traits at increasing plant diversity, with a longer duration of weeding and a longer time of colonization
Genomik-basierte Verbesserung des heimischen Sojazuchtmaterials und Etablierung eines molekularen Screeningsystems für Soja-Pathogene
Zur Einleitung von Pflanzenschutzmaßnahmen bei Soja ist es essentiell, Informationen über vorhandene Pathogene zu gewinnen. Basierend auf der quantitativen Real Time-PCR wurden Einzelnachweise für die Hauptpathogene der Sojabohne in Deutschland entwickelt. Die Pathogenität der Krankheitserreger wurde geprüft und das Inokulationsverfahren für weitere Untersuchungen etabliert. Erste Mehrfach-Nachweise für verschiedene Erreger und Probentypen wurden entwickelt, die für eine frühzeitige Detektion von Erregern in Soja-Proben (Saatgut, Pflanze, Boden) verwendet werden können.
Im Rahmen des Projekts wurde zudem durch Kombination von aktuellen und zukünftigen Klimaparametern sowie Genotypisierungs- und Phänotypisierungsdaten eine Kernkollektion von Akzessionen erstellt, die sich durch eine hohe Diversität auszeichnet und sich für den Anbau unter den Bedingungen von Zentraleuropa eignet. Dabei wurden neue Gene für Umweltadaptation identifiziert, für die molekulare Marker für die Züchtung entwickelt werden, und geeignete Akzessionen für die Einkreuzung in aktuelle Züchtungsprogramme wurden selektiert.
Die Ergebnisse zeigen außerdem klar, dass hochertragreiche Linien gezüchtet werden können, um die Sojaanbauregion nach Norden zu erweitern. Zudem bieten die gewonnenen Varianzkomponenten, Heritabilitäten und Merkmalskorrelationen eine solide Grundlage für die Gestaltung von Zuchtprogrammen, insbesondere auch von Speed-Breeding Programmen, die zukünftig mit genomischer und phänomischer Selektion beschleunigt werden können. Es wurden bereits erste Linien an die private Pflanzenzüchtung abgegeben, die in weiteren Prüfungen ermitteln, ob die Linien als Sorten zugelassen werden können.
Gerade in kühleren Lagen, wie z.B. in Norddeutschland, ist die Gefahr von Ertragseinbußen auf Grund von Kühlestress groß. In diesem Projekt wurden Linien von Kreuzungsnachkommenschaften und ein diverses Set aus Genbankakzessionen hinsichtlich ihres Hülsenansatzes nach einer Kühlestressphase charakterisiert. Das Testsystem führte zu reproduzierbaren Ergebnissen und es wurden erste QTL für den Hülsenansatz unter Stressbedingungen ermittelt
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