Biodiversity and ecosystem functioning are threatened by the loss and fragmentation of habitats providing vital resources for organisms. In agricultural landscapes, the loss of biodiversity may disrupt important ecosystem services (ES) such as crop pollination and natural pest control. Existing studies of fragmentation effects on functional biodiversity mostly characterize landscapes according to broad habitat categories such as “non-crop” or “semi-natural habitat”. The aim of the proposed project is to improve our mechanistic understanding of the drivers and consequences of effective functional fragmentation as a prerequisite for robust predictions of ES. We will examine (i) the resource requirements of key insect pollinators and natural enemies of agricultural pests, (ii) effects of the spatio-temporal distribution of these resources on pollinators and natural pest enemy communities in agricultural landscapes plus the functional consequences on ES delivery to crops, and (iii) their interactions with resources at the community level (ecological networks). Food resource requirements will be quantified using (i) pollen present on field-captured solitary bees, bumblebees, ladybirds and lacewings (aphid predators) and (ii) consumed prey (aphid) species through gut content analysis of predators (ladybirds) using next generation sequencing. From this, we will develop functional habitat maps for 48 landscapes that consider the spatial distribution of resources and their temporal availability relative to focal crops. Predictions about the effects of temporally preceding or synchronous alternative resources will be tested in a field survey of focal insect species in these 48 landscapes, while also quantifying the levels of ES delivery in focal crop fields. In addition, we will test fitness effects of spatio-temporal resource availability on pollinators by monitoring bumblebee colonies in the different landscapes in Germany. The fundamental ecological knowledge on spatio-temporal resource use affecting the structure and dynamics of plant-pollinator and predator-prey communities, their interactions and functional consequences gained by the proposed research, will help to improve landscape management and agri-environment schemes aimed at promoting functional biodiversity and ecosystem services in agricultural landscapes. In Landau, we focus on the pollinators part. In addition to Bombus terrestris, we have chosen Osmia bicornis and Osmia cornuta as model organisms.

Philipp W. Eckerter

Martin Entling

2020-2023

German Research Foundation (DFG)

Swiss National Science Foundation (SNSF)

Felix Herzog

Matthias Albrecht

William

Jordan Cuff

Willy Tinner

Erika Gobet

Laia Mestre

Colette Bertrand

Lolita Ammann

Aliette Bosem-Baillod

Ammann L, Moorhouse-Gann R, Bertrand C, Mestre L, Cuff J, Pérez Hidalgo N, Ellison A, Herzog F, Entling MH, Albrecht M & Symondson WOC (2020) Insights into aphid prey consumption by ladybirds: Optimising field sampling methods and primer design for High Throughput Sequencing. PLOS ONE 15: e0235054.

Bertrand C, Eckerter PW, Ammann L, Entling MH, Gobet E, Herzog F, Mestre L, Tinner W & Albrecht M (2019) Seasonal shifts and complementary use of pollen sources by key pollinators and aphid enemies in European agricultural landscapes. Journal of Applied Ecology 56: 2431–2442.

Eckerter, P. W., Albus, L., Natarajan, S., Albrecht, M., Ammann, L., Gobet, E., Herzog, F., Tinner, W., Entling, M.H. (2020): Using temporally resolved floral resource maps to explain bumblebee colony performance in agricultural landscapes. Agronomy 10(12): 1993

Biodiversity, ecosystem functions; agroecology, pollination; wild bees; Europe, Germany