| dc.contributor.advisor | Tscharntke, Teja Prof. Dr. | |
| dc.contributor.author | Udy, Kristy | |
| dc.date.accessioned | 2017-12-12T09:21:51Z | |
| dc.date.available | 2017-12-12T09:21:51Z | |
| dc.date.issued | 2017-12-12 | |
| dc.identifier.uri | http://hdl.handle.net/11858/00-1735-0000-0023-3FA9-B | |
| dc.identifier.uri | http://dx.doi.org/10.53846/goediss-6634 | |
| dc.identifier.uri | http://dx.doi.org/10.53846/goediss-6634 | |
| dc.language.iso | eng | de |
| dc.rights.uri | http://creativecommons.org/licenses/by-nc-nd/4.0/ | |
| dc.subject.ddc | 630 | de |
| dc.title | Scaling of Animal Communities: From Local and Landscape to Global Processes | de |
| dc.type | doctoralThesis | de |
| dc.contributor.referee | Scherber, Christoph Dr. | |
| dc.date.examination | 2017-07-11 | |
| dc.description.abstracteng | Animal communities are influenced by processes changing from the local to
global scale. Local processes include resource and habitat availability, while
landscape processes are often driven by habitat availability and heterogeneity
that shapes the species pool and population size. At the global scale, area and
environmental heterogeneity are major processes influencing animal communities.
I determined the influence of local and landscape scale processes on plant-pollinator
communities at different levels of urbanisation (farmland, villages and cities). The
influence of landscape was separated from that of the sampling unit by conducting
pollinator observations on phytometer plants experimentally placed in the different
landscapes (grassy field margins in farmland and gardens in villages and cities).
Pollinator diversity and abundance was highest in farmland and villages, but species
group identity changed with a number of wild bee species only present in gardens in
villages and cities. Plant-pollinator interaction networks in farmland sites were more
robust with higher interaction strength compared with networks in villages and cities.
Bumblebee movement patterns were analysed using the same landscapes as
the plant-pollinator experiment, but with farmhouse gardens added. I examined how
local resources and landscape type affect bumblebee foraging behaviour and colony
performance. I placed 32 Bombus terrestris colonies along the farmland to urban
gradient and analysed local and long-range movement patterns of bumblebees to assess
where pollinators forage in urban areas. Additionally, I measured if B. terrestris colony
growth depends on resource availability in the direct surroundings of the colony or
on landscape type. B. terrestris workers visited plants providing floral resources in
the direct surroundings of the colonies. Furthermore, the workers foraged in greater
distances to their colonies, if the mass flowering crop oilseed rape was flowering.
I investigated the influence of urban area size by studying arthropod
communities along an urbanisation gradient from small villages to cities. I sampled
arthropods in gardens and public green spaces at the edge and centre of urban areas
to determine the relative importance of local and landscape influence on community
composition. Arthropods sampled were from different taxa: Coleoptera, Araneae
and Hymenoptera. Araneae and Hymenoptera were influenced only by the local
surroundings (green space type and position in an urban area), whereas Coleoptera communities were influenced by both local and landscape effects (urban area size).
I also investigated whether environmental heterogeneity (niche processes) or
space (neutral processes) are better predictors of mammal species richness patterns at
the global scale. The relative influence of these two processes has not been tested at
the global level. I used a burning algorithm to increase both area and environmental
heterogeneity simultaneously. Niche processes explain global species richness
relationships better than neutral processes. The environmental factors that explain
most variation in species richness were either the range in elevation or in precipitation.
In conclusion, local and landscape scale processes influenced arthropod community
structure in urban areas. Abundance and diversity respond to local resources and habitat type, while community composition was influenced by the heterogeneity of the surrounding landscape in a taxon-specific way. The importance of environmental heterogeneity scales up to the entire globe as I found it is also an important predictor of mammal species richness. By determining at which scale species richness and animal communities are influenced, this study increases our understanding of how the ecological world is structured. | de |
| dc.contributor.coReferee | Holger, Kreft Prof. Dr. | |
| dc.subject.eng | Urban Ecology | de |
| dc.subject.eng | Invertebrates | de |
| dc.subject.eng | Plant-pollinator network | de |
| dc.subject.eng | Global mammal richness | de |
| dc.identifier.urn | urn:nbn:de:gbv:7-11858/00-1735-0000-0023-3FA9-B-2 | |
| dc.affiliation.institute | Fakultät für Agrarwissenschaften | de |
| dc.subject.gokfull | Land- und Forstwirtschaft (PPN621302791) | de |
| dc.identifier.ppn | 1008752630 | |