Vogelarten der Agrarlandschaft als Bioindikatoren für landwirtschaftliche Gebiete

Vögel werden in vielfacher Weise als Bioindikatoren genutzt. Der Zustand der biologischen Vielfalt in Deutschland wird im Rahmen der Nationalen Biodiversitätsstrategie durch den Indikator „Artenvielfalt und Landschaftsqualität“ abgebildet, der hierfür auf Vogelbestandsdaten zurückgreift. Neben verschiedenen anderen lebensraumspezifischen Teilindikatoren wird dabei auch der Zustand der Vögel des Agrarlandes abgebildet. Vogelarten der Agrarlandschaft zeigen in Deutschland wie in ganz Europa innerhalb der letzten Jahrzehnte beträchtliche Bestandsrückgänge, die auf Veränderungen der landwirtschaftlichen Nutzung zurückgeführt werden. Diese Veränderungen bilden sich in einer Entwicklung des Teilindikators „Agrarland“ weg von dem Zielwert ab, gleichzeitig ist der Indikator aktuell weit vom Zielwert entfernt. In dieser Publikation wird aufgezeigt, dass der Teilindikator repräsentativ für die Entwicklung der Artenvielfalt in der Agrarlandschaft und für die Entwicklung der Vogelarten der Agrarlandschaft ist. Dazu werden Indikatoren mit verschiedenen Artenzusammensetzungen und –anzahlen ohne Zielwertbezug erstellt und ihre Trends mit dem des Indikatorartensets des Teilindikators „Agrarland“ für den Zeitraum 1990-2010, sowie die Teilzeiträume 1990-1999 und 2000-2010 verglichen. Es ergeben sich lediglich bei 2 Artensets für den Teilzeitraum 2000-2010 signifikante Unterschiede, die mit der Artenzusammensetzung dieser Indikatoren erklärbar sind. In Zukunft sollten zusätzliche Datenquellen (z.B. zu Nutzungsintensität, Anbaufrucht, Daten zur Applikation von Pflanzenschutzmitteln) und vertiefende Untersuchungen (z. B. zur Biotopausstattung) auf Teilmengen bestehender Monitoringfl ächen genutzt werden, um die Gründe für Bestandsrückgänge der Vogelarten der Agrarlandschaft näher zu beleuchten. Stichwörter: Indikatoren, Artenvielfalt und Landschaftsqualität, Monitoring häufiger BrutvögelFarmland birds as bio-indicators for agricultural areasAbstractBirds are frequently used bio-indicators. The state of biodiversity in Germany is assessed using the indicator “Species diversity and landscape quality” in the course of the national sustainability strategy, by means of bird population data. Within this indicator, besides other habitat-specifi c partial indicators, the state of farmland birds is assessed. Farmland birds in Germany as in the whole of Europe have shown large population declines during the last decades which are attributed to changes in agricultural use. Those changes show in the negative development of the partial indicator “farmland”, signifi cantly departing from the target value set by the national sustainability strategy. In this publication, we examine the representativeness of the development of the partial indicator “farmland” consisting of 10 species for a larger set of farmland bird species. Thus, indicators consisting of diff erent sets and numbers of species are created without referring to target values. Their trends are compared to the trend of an indicator created from the species set of the partial indicator “farmland” within the indicator “Species diversity and landscape quality”, both for the time frame 1990-2010 and for the partial time frames 1990-1999 and 2000-2010, respectively. Signifi cant diff erences for the partial time frame 2000-2010 are demonstrated for 2 indicators, and are discussed in terms of their respective species sets. The species set of the partial indicator “farmland” within the indicator “Species diversity and landscape quality” is representative of the population declines of farmland birds since the mid 1990´s. Prospectively, additional data sources (e.g. data on land use, pesticide application etc.) and more detailed examinations on subsets of existing monitoring plots should be used to shed light on potential causes of declines in farmland birds. Keywords: Indicators, species diversity and landscape quality, Common Breeding Bird Surve

Konzeption und Entwicklung eines plattformunabhängigen Tools zum netzwerkweiten Daten-Management und anwendungsspezifische Erpro

In dieser Arbeit auf die Probleme beim Daten-Management in heterogenen Netzwerken eingegangen Deshalb wird: - eine Situationsanalyse für das Daten-Management vorgenommen, - der Datenfluss beim Daten-Management in heterogenen Netzwerken analysiert, - die Aufgaben eines Daten-Management-Systems bestimmt, - benutzbare Standards zu verglichen, - alternative Verfahren zu diskutieren, - eine Konzeption für ein Daten-Management-System entwickelt, - die Konzetion in ein lauffähiges Programm umzusetzen und - dieses an Beispielen zu erproben. Ein weiteres Augenmerk liegt auf der Untersuchung der Eignung der plattformunabhängigen Programmiersprache JAVA für den Einsatz in größeren Software-Projekten

Equivalence and Characterizations of Linear Rank-Metric Codes Based on Invariants

We show that the sequence of dimensions of the linear spaces, generated by a given rank-metric code together with itself under several applications of a field automorphism, is an invariant for the whole equivalence class of the code. The same property is proven for the sequence of dimensions of the intersections of itself under several applications of a field automorphism. These invariants give rise to easily computable criteria to check if two codes are inequivalent. We derive some concrete values and bounds for these dimension sequences for some known families of rank-metric codes, namely Gabidulin and (generalized) twisted Gabidulin codes. We then derive conditions on the length of the codes with respect to the field extension degree, such that codes from different families cannot be equivalent. Furthermore, we derive upper and lower bounds on the number of equivalence classes of Gabidulin codes and twisted Gabidulin codes, improving a result of Schmidt and Zhou for a wider range of parameters. In the end we use the aforementioned sequences to determine a characterization result for Gabidulin codes.Comment: 37 pages, 1 figure, 3 tables, extended version of arXiv:1905.1132

Towards a more mechanistic understanding of traits and range sizes

ABSTRACT Aim An important, unresolved question in macroecology is to understand the immense inter-specific variation in geographic range sizes. While species traits such as fecundity or body size are thought to affect range sizes, a general understanding on how multiple traits jointly influence them is missing. Here, we test the influence of a multitude of species traits on global range sizes of European passerine birds in order to better understand possible mechanisms behind macroecological relationships. Location Global. Methods We evaluated the effect of life-history traits (fecundity, dispersal ability), ecological traits (habitat niche, diet niche, migratory behaviour, migratory flexibility) and a morphological trait (body size) on the global range sizes of 165 European passerines. We identified hypotheses from the literature relating traits to range size and used path analysis to test them. Results Fecundity, dispersal ability and habitat niche breadth had a direct positive effect on range size. Diet niche position had a direct negative effect on range size. Habitat niche breadth also had an indirect positive effect via higher fecundity. Migratory behaviour had an indirect positive effect via better dispersal ability. Body size had a strong positive direct effect which was reduced by negative indirect effects via several other traits. Main conclusions Geographic range sizes of European passerines were influenced by life-history traits (fecundity and dispersal ability), ecological traits (habitat niche breadth, diet niche position and migratory behaviour) and by body size. Traits influenced range size both directly and indirectly. Body size effects were particularly complex, with positive and negative effects acting over different pathways. We show that it is necessary to disentangle the direct and indirect influence of multiple traits on range size to better elucidate the mechanisms that generate macroecological relationships

Tracking Progress Toward EU Biodiversity Strategy Targets : EU Policy Effects in Preserving its Common Farmland Birds

Maximizing the area under biodiversity-related conservation measures is a main target of the European Union (EU) Biodiversity Strategy to 2020. We analyzed whether agrienvironmental schemes (AES) within EU common agricultural policy, special protected areas for birds (SPAs), and Annex I designation within EU Birds Directive had an effect on bird population changes using monitoring data from 39 farmland bird species from 1981 to 2012 at EU scale. Populations of resident and short-distance migrants were larger with increasing SPAs and AES coverage, while Annex I species had higher population growth rates with increasing SPAs, indicating that SPAs may contribute to the protection of mainly target species and species spending most of their life cycle in the EU. Because farmland birds are in decline and the negative relationship of agricultural intensification with their population growth rates was evident during the implementation of AES and SPAs, EU policies seem to generally attenuate the declines of farmland bird populations, but not to reverse them.Peer reviewe