Publication Details

Category Text Publication
Reference Category Journals
DOI 10.1111/1365-2435.14122
Licence creative commons licence
Title (Primary) Resource supply and organismal dominance are associated with high secondary production in temperate agricultural streams
Author Wild, R.; Gücker, B.; Weitere, M.; Brauns, M.
Source Titel Functional Ecology
Year 2022
Department FLOEK
Volume 36
Issue 9
Page From 2367
Page To 2383
Language englisch
Topic T5 Future Landscapes
Data and Software links
Keywords agriculture; benthic macroinvertebrates; biotic homogenization,;consumer-resource; dominance; ecosystem function; landuse; secondary production

Agricultural land use affects the environmental and biological characteristics of stream ecosystems through multiple pathways including nutrient and pesticide contamination, riparian clear-cutting, and hydromorphological degradation. These changes in the abiotic environment can have a direct effect on the productivity of macroinvertebrate communities through environmental filtering and via altered resource conditions encompassing a shift from allochthonous to autochthonous primary production and changes in elemental stoichiometry and food quality. Additionally, macroinvertebrate productivity can be affected indirectly via biological mechanisms, such as changes in species interactions, richness, competition, and predation. We studied the effects of agriculture on structural and functional descriptors of macroinvertebrate communities by assessing environmental characteristics and macroinvertebrate secondary production (MSP), biomass, and density in two forested and two agricultural streams and investigated underlying biotic mechanisms. On average, MSP was 1.6–3.6, biomass 2.8–6.2, and density 5–13 times higher in agricultural than in forested streams. This pattern was associated with higher nutrient concentrations, standing crops of riparian herbaceous vegetation, suspended particulate organic carbon, quantity and quality of epilithic biofilms, and chlorophyll-a concentrations in seston and biofilm of the agricultural streams. Species richness and evenness were significantly lower in agricultural than in forested streams. A negative relationship between MSP and species richness and evenness indicated that density compensation and trait dominance were the prevalent mechanisms facilitating higher MSP in agricultural streams.

Our findings suggest that the loss of riparian canopy and excess nutrient conditions are the major environmental drivers contributing to homogenization of ecological niches

and dominance of highly productive non-insect generalist species. This study highlights the importance of an ecosystem approach to understanding how complex aggregate stressors affect the regulation of consumer-resource interactions. There is an urgent need to preserve or restore natural riparian vegetation, fostering habitat and resource diversity and limiting nutrient contamination to stream ecosystems.

Persistent UFZ Identifier
Wild, R., Gücker, B., Weitere, M., Brauns, M. (2022):
Resource supply and organismal dominance are associated with high secondary production in temperate agricultural streams
Funct. Ecol. 36 (9), 2367 - 2383 10.1111/1365-2435.14122