Effects of antimicrobial compounds on aquatic communities via bottom-up regulation (AQUA-CO-REG)

异源粗颗粒有机物（如凋落叶）的分解是淡水生态系统的基本功能，为当地和下游社区提供能量。之前的项目AQUA-REG使用抗菌物质研究自下而上的作用途径，重点是叶片微生物和碎屑碎纸机水平。开发了水生菌丝的Q-RT-PCR方法。AQUA-REG结果发表在7篇同行评议的论文中，更多的论文正在准备中。本研究旨在将AQUA-REG方法应用到大型无脊椎动物群落的模型中，包括无脊椎捕食者。为此，将采用一个新设计的溪流微观系统，该系统由接近自然的源头溪流连续供水。使用先前建立的抗菌剂作为标准化的化学应激源，AQUA-CO-REG通过受污染的叶片材料暴露模型群落。除了在动态能量收支理论中已经考虑到的主要定量（如能量的数量）联系外，在食物的非必需脂肪酸和必需脂肪酸组成等意义上的“能量质量”，将在AQUA-CO-REG中从食物网的角度进一步考虑。稳定同位素分析和基于q - rt - pcr的菌丝菌定量将补充所观察的端点套件。考虑到水生食物网中抗菌剂诱导的自下而上的直接影响途径的食物质量，拟议的项目可以确定影响的程度，并了解与这些影响相关的机制，如摄食可塑性、呼吸、应激耐受性或捕食者回避。

The breakdown of allochthonous coarse particulate organic matter like leaf litter is a fundamental function in freshwater ecosystems providing energy for local but also downstream communities. The predecessor project AQUA-REG has used antimicrobial substances to study bottom-up effect pathways with a focus on the leaf microorganismic and detritivore shredder level. Q-RT-PCR protocols for aquatic hyphomycetes were developed. AQUA-REG results were published in seven peer-reviewed papers, further papers are under preparation. The present proposal aims to take the AQUA-REG approach to the level of model macroinvertebrate communities, i.e. including invertebrate predators. To this end, a newly designed stream microcosm system fed continuously by water from a near-natural headwater stream will be employed. Using the previously established antimicrobials as standardized chemical stressors, AQUA-CO-REG exposes model communities via contaminated leaf material. Besides the mainly quantitative (e.g. amount of energy) linkages already considered e.g. in the dynamic energy budget theory, the “quality of the energy” in the sense of, for instance, non-essential and essential fatty acid composition of food, will be further considered in AQUA-CO-REG from a food web perspective. Stable-isotope analysis and Q-RT-PCR-based hyphomycete quantifications will complement the suite of endpoints looked at. Considering food quality for bottom-up directed effect pathways induced by antimicrobials in aquatic food webs, the proposed project allows to determine the magnitude of effects as well as to understand the mechanisms relevant for these effects at the community level, such as feeding plasticity, respiration, stress tolerance or predator avoidance.