We currently have funded PhD scholarships available in the Department of Biological Sciences, University of Hull. The scholarships are awarded to the best quality candidates. Anyone wishing to study the impacts of environmental change on the structure and dynamics of ecological networks should contact me in the first instance to discuss their ideas. See http://www2.hull.ac.uk/science/biological_sciences/people/academic_staff/darren_evans.aspx for more details about my lab.

headers Darren M Evans | 30 Jan 13:55

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PhD opportunities in the Stouffer Lab at the University of Canterbury
(New Zealand)

The Stouffer Lab at the University of Canterbury (New Zealand) is
seeking applicants for up to three fully-funded PhD fellowships to
work on topics related to ecological complexity and understanding the
structure and dynamics of ecological networks.

Because of the interdisciplinary nature of the projects, we are
interested in applicants from ecology, computational biology, computer
science, applied mathematics, engineering, physics, or other related
areas.

Interested applicants should see http://stoufferlab.org/opportunities/
for information on how to apply and for more information about our
research group.

Applications close 30 November 2011.

- Daniel

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Dear All,

For those of you yet without plans for this week (^_-), there will be
two-day mini-symposium on

      The structure and dynamics of ecological networks

held at University of Fribourg, CH, on 8-9 September 2011 (Thu and
Fri).

Registration is still open until Monday September 5.  For details, see
http://www.unifr.ch/biol/ecology/CUSO/FWSTR2011/index.html .

Best,
Axel

Dear colleagues

I recently defended my thesis entitled Food Web Ecology:

M. Hartvig. Food Web Ecology – individual life-histories and
ecological processes shape complex communities. 2011. ISBN:
978-91-7473-080-7. Ph.D. thesis, Department of Theoretical Ecology,
Lund University, Sweden.

It is available here:
http://hvig.dk/2011/03/food_web_ecology-phd_thesis/ . Printed books
are available upon request.

Abstract: This thesis sets out a food web framework for
size-structured populations. The framework enables an ecological
approach to food web modelling as the individual life-history from
birth, through maturation, and ultimately death is explicitly resolved
with the use of bioenergetics based on individual body size. Each
population resolves size-structure through a size-spectrum containing
the individual abundance as a continuous function of body size.
Individuals select prey items of a suitable size, which can be
popularised as "big ones eat smaller ones". This allows individuals to
change diet throughout life (life-history omnivory). In the framework
individual food consumption leads to growth in body size and
allocation to reproduction, which drives the population dynamics as
opposed to instantaneous population increase in unstructured food web
models. Paper I introduces the framework and shows how a simple
realistic parametrisation is possible when a trait-based species
characterisation is used. An analytical approximation of the food web
framework is derived, and validated through comparison with dynamic
simulations. Paper II extends the dynamic framework by also
considering space, and demonstrates how large food webs can be formed
through sequential community assembly. The resulting communities
resemble the topology of natural food webs as well as complying with
empirical data on diversity and biomass distributions -- demonstrating
that individual-level food encounter and prey-selection from the rule
"big ones eat smaller ones" lead to complex and realistic food webs.
Paper III uses the analytical solution of the framework to show the
conditions under which the many-small-eggs strategy of the fishes is a
viable strategy. Paper IV utilises the trait-based species description
to show that coexisting species pairs involved in intraguild predation
exist for all resource levels. The model thus explains empirically
observed coexistence at high resource levels contrary to contemporary
theoretical models. Paper V demonstrates how harvesting initiates a
trophic cascade that may propagate both downwards and upwards in
trophic levels, and that the harvesting pattern may influence whether
or not trophic cascades are empirically detected. In Paper VI the
analytical solution is used to provide a theoretical understanding of
empirically observed relationships between natural mortality, growth,
and production rates.

Do not hesitate contacting me if you have any questions (mh@...).

Cheers,
Martin

__________________________________________
Martin Hartvig -- Research website: http://hvig.dk/

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Dear food-webbers,

The following paper was recently published online in Proceedings B

Gagic, V.,Tscharntke, T., Dormann, C.F., Gruber, B.,Wilstermann, A.,Thies,C. 2011
Food web structure and biocontrol in a four-trophic level system across a landscape complexity gradient
doi:10.1098/rspb.2010.2645

Available at 
http://rspb.royalsocietypublishing.org/content/early/2011/02/07/rspb.2010.2645.abstract

Please contact Vesna Gagic (vgagic <at> gwdg.de) with any questions

Abstract

Decline in landscape complexity owing to agricultural intensification 
may affect biodiversity, food web complexity and associated ecological 
processes such as biological control, but such relationships are poorly 
understood. Here, we analysed food webs of cereal aphids, their primary 
parasitoids and hyperparasitoids in 18 agricultural landscapes differing 
in structural complexity (42–93% arable land). Despite little variation 
in the richness of each trophic group, we found considerable changes in 
trophic link properties across the landscape complexity gradient. 
Unexpectedly, aphid–parasitoid food webs exhibited a lower complexity 
(lower linkage density, interaction diversity and generality) in 
structurally complex landscapes, which was related to the dominance of 
one aphid species in complex landscapes. Nevertheless, primary 
parasitism, as well as hyperparasitism, was higher in complex 
landscapes, with primary parasitism reaching levels for potentially 
successful biological control. In conclusion, landscape complexity 
appeared to foster higher parasitism rates, but simpler food webs, 
thereby casting doubt on the general importance of food web complexity 
for ecosystem functioning.

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A message forwarded from Peter de Ruiter...
************************************************

Please pass this information to anyone who might be interested

Prof. dr. Peter C. de Ruiter, Biometris, Wageningen UR
Visiting address: Radix, Gebouw 107, Droevendaalsesteeg 1, 6708 PB, Wageningen
P.O.Box 100, 6700 AC Wageningen
Telephone: +31 (0)317 - 481368 (secr. 484085)
E-mail: Peter.deRuiter@... ; Web: www.biometris.nl
______________________________________________________________________________________

We look for candidates for two PhD-projects

Food webs describe biological communities in terms of feeding interactions, i.e. 'who eats whom'. In
ecosystems with many species, food web diagrams reveal highly complex networks of resource-consumer
interactions. From theoretical analysis it is known that such networks might be relatively unstable,
which means that the networks may easily fall apart when they are disturbed. In ecological terms this
means that environmental change may push species toward extinction. For that reason, the ecology of food
webs is much focused on what attributes of trophic networks are important to stability. 

Until now food web ecology primarily deals with consumer-resource interactions as  'material' flows from
resources to consumers. This means that it is only the amount of food consumed that is considered to be
important. While we know that food quality might be even important for the growth and survival of species.
Another aspect missing in current food web ecology is that by means of eating diseases might spread from
resources to consumers. 
This proposal aims to address both these aspects in food web models. These models will be based on
observations on real food webs. These food webs come from natural parks in Africa (Serengeti, Kruger) and
we have access to the large amount of observations on soil food webs as assembled in the Dutch Soil Survey
data set. 
The project is multi-disciplinary, as it brings together ideas on food web ecology, stoichiometry (the
science of food quality), epidemiology, and mathematics. 

We organise the program along the overall objective of the analysis of the interrelations between food web
complexity, stability, and the quality of consumer/resource interaction in the form of two joint
PhD-projects, based on a common theoretical framework and guided by the same empirical data. Both
projects will focus on the idea of composite interaction strength that addresses the multi-dimensional
`quality' of the material flow, regarding nutritional composition  (Sub-project 1) and infectious
disease agents (Sub-project 2). The aim is to develop food web models in terms of parallel trophic
networks in which the feeding rates are represented as carrier system for the transmission of nutrients
and/or disease agents. 

Sub-project 1. Stoichiometry in food webs 
Sub-project 2. Infectious disease agents in food webs 
Please mention in your application letter which of the 2 projects you apply for. Of course, you can also
apply for both. 

For more information: 
Sub-project 1. Peter de Ruiter - Peter.deRuiter@... 
Sub-project 2. Hans Heesterbeek - J.A.P.Heesterbeek@... 
Sluitingsdatum: 28 February 2011

Mon	Tue	Wed	Thu	Fri	Sat	Sun

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3	January 2012
1	November 2011
1	October 2011
1	September 2011
1	June 2011
1	March 2011
3	February 2011
2	January 2011
1	December 2010
2	November 2010
4	March 2010
1	September 2009
2	May 2009
1	April 2009
3	February 2009
3	January 2009
1	December 2008
5	November 2008
2	October 2008
2	September 2008
3	July 2008
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3	December 2007
1	November 2007
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3	July 2007
2	June 2007

British Ornithologist's Union conference

PhD opportunities: ecological networks

PhD Studentships in Biological Sciences

University of Hull

Postdoctoral position: impacts of climate change on farmland foodwebs

PhD opportunities in the Stouffer Lab

ALLOMETRY IN SOIL NEMATODES: ESA Data Paper and OA Research Article

Fribourg Ecology & Evolution Days 2011

Thesis on food webs

Paper on allometry as "disturbance index" in soil agroecosystems

Paper: Food web framework for size-structured populations

Paper announcement

vacancies