Refine
Document Type
Keywords
- Acari (mites) (1)
- Collembola (1)
- General Biochemistry (1)
- General Chemistry (1)
- General Physics and Astronomy (1)
- Genetics and Molecular Biology (1)
- Multidisciplinary (1)
- Nematoda (1)
- bait-lamina (1)
- ecosystem function (1)
Institute
1. Carabids are abundant in agroecosystems and provide biocontrol services by feeding on weed seeds and pests. We compare the effects of two fundamentally different agri‐environmental schemes (AES) on the numeric and trophic responses of four common carabid species: Anchomenus dorsalis, Poecilus cupreus, Pseudoophonus rufipes and Pterostichus melanarius.
2. In six cereal fields under organic farming and six sown flowering fields, 10 290 individuals of the four species were sampled to quantify their numeric response. The activity density of all species was higher in organically managed cereal fields compared to flowering fields.
3. We analysed naturally occurring stable isotope ratios of carbon and nitrogen in 138 carabid individuals to quantify isotopic niches and the diet contribution of soil‐ versus plant‐based resources. Resources from the soil (‘brown’) energy channel were more important than resources from the plant (‘green’) energy channel in the diet of all species, particularly in P. melanarius.
4. Isotopic niches were larger for P. rufipes and P. melanarius in flowering fields than in organically managed cereal fields. Moreover, differences between AES types were observed in the diet contribution derived from both energy channels: A. dorsalis and P. cupreus incorporated higher proportions of plant‐based resources in organically managed cereal fields compared to flowering fields.
5. Similar numeric, but different trophic responses suggest that AES type may alter arthropod food webs beyond simple changes in carabid densities. Such ‘hidden’ modifications in the resource utilisation of generalist predators deserve more attention to adequately evaluate the ecological consequences of AES.
Für eine Gemeinsame Agrarpolitik, die konsequent zum Erhalt der biologischen Vielfalt beiträgt
(2018)
A slow-fast trait continuum at the whole community level in relation to land-use intensification
(2024)
AbstractOrganismal functional strategies form a continuum from slow- to fast-growing organisms, in response to common drivers such as resource availability and disturbance. However, whether there is synchronisation of these strategies at the entire community level is unclear. Here, we combine trait data for 2800 above- and belowground taxa from 14 trophic guilds spanning a disturbance and resource availability gradient in German grasslands. The results indicate that most guilds consistently respond to these drivers through both direct and trophically mediated effects, resulting in a ‘slow-fast’ axis at the level of the entire community. Using 15 indicators of carbon and nutrient fluxes, biomass production and decomposition, we also show that fast trait communities are associated with faster rates of ecosystem functioning. These findings demonstrate that ‘slow’ and ‘fast’ strategies can be manifested at the level of whole communities, opening new avenues of ecosystem-level functional classification.