Freixa Anna, Ortiz-Rivero Javier, Sabater Sergi
Catalan Institute for Water Research (ICRA-CERCA), Carrer Emili Grahit 101, 17003 Girona, Spain.
University of Girona, Plaça de Sant Domènec 3, 17004, Girona, Spain.
MethodsX. 2023 Feb 22;10:102089. doi: 10.1016/j.mex.2023.102089. eCollection 2023.
River biofilms are biological consortia of autotrophs and heterotrophs colonizing most solid surfaces in rivers. Biofilm composition and biomass differ according to the environmental conditions, having different characteristics between systems and even between river habitats. Artificial substrata (AS) are an alternative for in situ or laboratory experiments to handle the natural variability of biofilms. However, specific research goals may require decisions on colonization time or type of substrata. Substrata properties (i.e., texture, roughness, hydrophobicity) and the colonization period and site are selective factors of biofilm characteristics. Here we describe the uses of artificial substrata in the assessment of ecological and ecotoxicological responses and propose a decision tree for the best use of artificial substrata in river biofilm studies. We propose departing from the purpose of the study to define the necessity of obtaining a realistic biofilm community, from which it may be defined the colonization time, the colonization site, and the type of artificial substratum. Having a simple or mature biofilm community should guide our decisions on the colonization time and type of substrata to be selected for the best use of AS in biofilm studies. Tests involving contaminants should avoid adsorbing materials while those ecologically oriented may use any AS mimicking those substrata occurring in the streambed.•We review the utilization of different artificial substrata to colonize biofilm in river ecology and ecotoxicology.•We propose a decision tree to guide on selecting the appropriate artificial substrata and colonization site and duration.•Type of artificial substrata (material, size, shape...) and colonization duration are to be decided according to the specific purpose of the study.
河流生物膜是定殖于河流中大多数固体表面的自养生物和异养生物的生物群落。生物膜的组成和生物量因环境条件而异，不同系统之间甚至河流栖息地之间都具有不同的特征。人工基质（AS）是原位或实验室实验中应对生物膜自然变异性的一种替代方法。然而，特定的研究目标可能需要对定殖时间或基质类型做出决策。基质特性（即质地、粗糙度、疏水性）以及定殖时期和地点是生物膜特征的选择因素。在此，我们描述了人工基质在评估生态和生态毒理学响应中的用途，并提出了一个决策树，以指导在河流生物膜研究中最佳使用人工基质。我们建议从研究目的出发，确定获得真实生物膜群落的必要性，据此可以确定定殖时间、定殖地点和人工基质类型。拥有简单或成熟的生物膜群落应指导我们在定殖时间和基质类型方面做出决策，以便在生物膜研究中最佳地使用人工基质进行研究。涉及污染物的测试应避免使用吸附性材料，而那些以生态为导向的测试则可以使用任何模仿河床中出现的基质的人工基质。
•我们综述了不同人工基质在河流生态和生态毒理学中用于定殖生物膜的情况。
•我们提出了一个决策树来指导选择合适的人工基质、定殖地点和持续时间。
•人工基质类型（材料、尺寸、形状等）和定殖持续时间应根据研究目的来确定。
