Variable temperature effects between heterotrophic stream processes and organisms

作者：Jérémy Jabiol, Alice Gossiaux, Antoine Lecerf, Thibaut Rota, François Guérold, Michaël Danger, Pascal Poupin, Franck Gilbert, Éric Chauvet · 发表于：Freshwater Biology · 年份：2020 · DOI：10.1111/fwb.13520 · 被引用次数：30 · 研究领域：Freshwater macroinvertebrate diversity and ecology、Fish Ecology and Management Studies、Aquatic Invertebrate Ecology and Behavior

Abstract Temperature is known to stimulate metabolism with cascading effects on multiple biological processes. These effects may, however, vary across processes, types of organisms or levels of biological organisation. They can also vary with nutrient availability, with potentially stronger temperature effects when nutrients are not limiting. This context dependence of temperature effects on processes challenges our ability to anticipate their consequences on ecosystems in a changing world. In headwater streams, the decomposition of allochthonous leaf litter, driven by both microbial decomposers and invertebrates, is known to respond to both temperature and nutrient availability. These food webs are highly tractable and a useful model system to investigate the variations of temperature effects on processes across types of organisms (microbes versus invertebrates), resource availability levels (nutrient concentration), and levels of biological organisation (from individual to ecosystem). In a microcosm experiment, we measured the effects of temperature and nitrogen availability (four levels each) on respiration rates of litter-consuming microbes and invertebrates and their decomposition activity in different contexts of food web complexity. The latter included one treatment without invertebrate detritivore (microbial decomposers only), three single invertebrate taxa ( Gammarus , Potamophylax , and Sericostoma ) treatments, and one mixed invertebrate taxa treatment (three‐speci...